E-text prepared by Chris Curnow and the Online Distributed Proofreading
Team (http://www.pgdp.net) from page images generously made available by
Internet Archive (https://archive.org)



Note: Project Gutenberg also has an HTML version of this
      file which includes the original illustrations.
      See 46634-h.htm or 46634-h.zip:
      (http://www.gutenberg.org/files/46634/46634-h/46634-h.htm)
      or
      (http://www.gutenberg.org/files/46634/46634-h.zip)


      Images of the original pages are available through
      Internet Archive. See
      https://archive.org/details/lifeofrichardtre02trevrich





LIFE OF RICHARD TREVITHICK,

With an Account of His Inventions.

by

FRANCIS TREVITHICK, C.E.

Illustrated with Engravings on Wood by W. J. Welch.

VOLUME II.







London:
E. & F. N. Spon, 48, Charing Cross.
New York:
446, Broome Street.
1872.

London: Printed by William Clowes and Sons, Duke Street,
Stamford Street and Charing Cross.




CONTENTS OF VOLUME II.


  CHAPTER XVII.

  VARIOUS INVENTIONS.

  Stone-crushing mill, 1804--Portable puffer, 1805--Staffordshire
  potteries--Engine for South America--Diversity of steam
  appliance--Numerous high-pressure engines--West India Dock
  locomotive--Engines at Newcastle--Blacklead lubricator--Engines in
  Wales--Mine engines on wheels, 1804--Engines in London--Engines to be
  sold in market towns--Blast-furnaces--Aërated steam-boiler--St. Ives
  Breakwater--Dolcoath blast copper furnace--Davies Gilbert's opinion of
  the aërated steam-boiler--Trevithick's advice to a brewer--Agricultural
  engines--West India engines--Thrashing engine--Horizontal
  engines--Expansive steam--Cold surface condenser--Air-pump--Expansive
  cam--Fire-bars--Comparison with Watt's engine--Stone-boring engine,
  1813--Plymouth Breakwater, reduction in cost--Locomotive engine,
  1813--Stone splitting--New method of stone boring, 1813--Screw bit,
  1813--Falmouth Harbour--Exeter Bridge--Engine at Lima--Proposed train
  from Buenos Ayres to Lima--West India portable engine      Page 1-35


  CHAPTER XVIII.

  AGRICULTURAL ENGINES; LOSS OF PAPERS.

  Sir Christopher Hawkins's thrashing machine, 1812--Report of three
  wise men--Cost of horse and steam power--Wheal Liberty engine--Sir
  John Sinclair and the Board of Agriculture--Cost of engine--Power of
  engine--Welsh locomotive--Trevithick on steam agriculture--West Indies
  engine--Horse-power--Trevithick on patents--Engines in charge of
  labourers--Teapot--Detail of agricultural engine--Lord Dedunstanville's
  thrashing machine--Plymouth Breakwater locomotive--Wheal Prosper
  engine--Wheal Alfred engine--Steam-plough--Cultivation of
  commons--Combined steam-tormentor, narrower, and shoveller--Mr.
  Rendal's thrashing machine--Cost and work performed by thrashing
  engines--Their durability--Bridgenorth engine--Trevithick's drawings
  light the tires      36-68


  CHAPTER XIX.

  POLE STEAM-ENGINE.

  Return to Cornwall, 1810--Wheal Prosper pole vacuum engine,
  1811--Cylindrical boilers, 1811--Steam pressure, 100 lbs.--Duty
  of engine, 40 millions--Expansive working, 1811--Herland
  high-pressure pole puffer, 1815--Steam pressure, 150 lbs.--Boiler
  making--Comparison with Watt's engine--Blue-fire--Steam--Patent
  specification--Steam-ring stuffing box--Engines in Lima--A 33-inch
  pole-puffer more powerful than a 72-inch Watt engine--Description
  of pole engine and boilers--Trevithick's calculation--Trial of
  Herland engines--Steam-cushion--Power of the pole-engine--Defective
  workmanship--Sims examines the pole-engine--Opposition from
  shareholders--Defective boilers--Challenge to Woolf--Davies
  Giddy's opinion--First cost, and cost of working one-third of
  the Watt engine--Meeting of opposing shareholders--Duty of the
  high-pressure steam pole puffer-engine, 1816--Comparison with the Watt
  engine--Combined high-pressure pole and cylinder for expansion--Wheal
  Alfred Watt engine converted to high pressure--Wheal Chance combined
  engine--Mr. Michael Williams's opinion--Woolf and Trevithick  Page 69-113


  CHAPTER XX.

  THE WATT AND THE TREVITHICK ENGINES AT DOLCOATH.

  Early steam-engines--Semicircular boiler, 1775, net power 7 lbs.
  on the inch--Watt's statement in 1777--Engines in Dolcoath--Watt's
  engine, 1778--Watt's engine at Herland, 1798--Trevithick's tubular
  boiler, 1799--Reconstruction of the Carloose 45-inch, 1799--Gross and
  net power of engines--Comparison of Newcomen, Watt, and Trevithick
  engines--Boiler explosion, 1803--Strong rivalry with Watt--Locomotive
  at Coalbrookdale, 1803--Watt's proposed locomotive--Competition in
  Wales--Numerous high-pressure engines, 1803--Patent difficulty--Watt's
  opposition, 1804--Government inquiry--Competitive trials in
  Wales--Tramway locomotive, 1804--The bet--Opposition because of saving
  of labour--Worcester engine--West India Docks engine--High-pressure
  steam condensing engines--One or two cylinders for expansion--Sirhowey
  boilers--Mr. Homfray's opinion of the Watt opposition--Mr.
  Whitehead makes engines in Manchester--Cylindrical tubular boiler
  in Wales for large engines, 1805--Watt contests at Dolcoath,
  1805--Steam-blast--Superiority of high-pressure whim-engines--Proposed
  boiler for the large pumping engine, 1806--Steam pressure--The Watt
  boiler--Comparison of size of fire-place and coal used--Dredger
  contract--Theory of steam--Trevithick's Dolcoath boiler when
  applied to the Watt engine, with expansive gear, to save 300l.
  monthly, 1806--Momentum of pumping engine--Continued tests of high
  and low pressure whim-engines at Dolcoath--Watt engine put aside,
  1806--High-pressure engines ordered, 1806--High-pressure pumping
  engine for Wheal Abraham, 1806--Disputed patent right--Expansion
  reduces heat--Boiler for the Watt 63-inch engine, 1806--Cost of
  Trevithick's boiler--Advantage of small tubes in boilers--Trinity
  Board--Watt's steam-cylinder unsuitable for high steam, 1806--Sims'
  trial of engines--Little fight--Tubular boilers, 1806--High-pressure
  steam pumping engines, 1818--Reporter of engines--Application to
  Government, 1810--Dolcoath engines and boilers--High steam to the Watt
  engine--Duty of engines, 1812--Watt's boiler thrown out--Expansive
  valve--Dolcoath manager--Saving by boilers and expansive working,
  1812--Lean's reports--Increased duty of the three old Dolcoath
  engines, 1814--76-inch engine, 1816--80,000l. a year saved--Durability
  of engine--Its removal--Cylindrical boilers--Hornblower and Watt
  engines--Davies Gilbert's report, 1798--Lean's report, 1816--Watt's
  views of expansive working--Watt's steam of 1 or 2 lbs. to the
  inch--Pole's statement--Engine at Marazion, 1804--Woolf in
  Cornwall--Rees' Cyclopædia--'Encyclopædia Britannica'--Application to
  Parliament--Wheal Towan--Newcomen and Watt engines--Pompe-à-feu 'La
  Belle Machine,' Dolcoath     Page 114-194


  CHAPTER XXI.

  ENGINES FOR SOUTH AMERICA.

  Engines for Lima, 1813--Uville's application to Watt--High-pressure
  model--Cerro de Pasco mines--Uville's return in search of
  Trevithick--Engines ordered--Pump-work--Modern pumping engines--Money
  difficulty--Weight of pieces--'Sanspareil' of 1813--Expansive
  working--Quartz crusher--Locomotive for South America, 1813--Sketch
  of winding engine--Their simplicity of form--Power and cost of
  engines--Trevarthen and Bull to accompany the engines--A third
  man recommended--Boilers put together at Cerro de Pasco--Uville's
  arrest--Trevithick a shareholder--Vivian's application--Departure of
  machinery, 1814--Uville's agreement--Invoice of engines sent
  Page 195-220


  CHAPTER XXII.

  PERU.

  Agreement for working the Peruvian mines, 1812--Uville and
  Watt, 1811--Uville and Trevithick, 1813--Uville's opinion of
  Trevithick--Estimated value of the mines--Machinery reached Peru,
  1815--Trevithick's departure from Penzance, 1816--Mr. Edmond's
  statement--Cerro de Pasco mines in 1850--Report from the Viceroy of
  Peru, 1816--Report from the Magisterial Deputation of Yauricocha,
  1816--Despatch from the Governor of the Province of Tarma,
  1816--Pumping engines at work--The Viceroy's reply--Report in the
  'Lima Gazette,' 1816--Trevithick's reception at Lima--Trevithick's
  report, 1817--Differences between Trevithick and Uville--Trevithick's
  thoughtless acts--His visit to the nunnery--The Lord Warden proposed
  to erect a statue in silver to Trevithick--Bust of Trevithick
  in Cornwall--Quicksilver--Sunk ship--Chili--Copper and silver
  mine--Departure from Lima--Cerro de Pasco mines    Page 221-259


  CHAPTER XXIII.

  COSTA RICA.

  Gerard at Punta de Arenas, in the Pacific, in 1822--Nicolas
  Castro worked a gold mine, 1821--Alverado's ore-grinding machine,
  1822--Climate of Costa Rica--Mines in the Cordillera--Canal
  from the river Machuca to Quebrada-honda--Castro's mine--Padre
  Arias, or the Priest's mine--Trevithick and Gerard's proposal
  for iron railroads, &c., for the mines of Costa Rica, 1827--New
  line of road from San Juan, on the Atlantic, to the Costa Rica
  mines--Serapique River navigable--Trevithick's diary--A mule track
  easily constructed--Comparative distance to the mines from the
  head of the Serapique on the Atlantic, and Punta de Arenas on the
  Pacific--Trevithick nearly drowned in the Serapique--Nearly starved
  before reaching San Juan--Performs a surgical operation--Designed
  the locomotive between breakfast and dinner--Robert Stephenson and
  Trevithick at Carthagena--Nearly drowned in the Magdalena--Saved by Mr.
  Bruce Napier Hall--Trevithick nursed Robert Stephenson   Page 260-275


  CHAPTER XXIV.

  RETURN TO ENGLAND.

  Bodmin School, 1827--Cube root--Trevithick's reception--Saving in
  Cornish mines--Model gun--Gerard's return, 1827--His meeting Robert
  Stephenson--His remarks on Costa Rica--Montelegre's search for a better
  line of road--Mr. M. Williams's proposal--Change of Ministry, and the
  gun-carriage--Model of iron packet-ship and engine--Robert Stephenson's
  remarks on mining--Trevithick's rejection of purchase-money
  Page 276-283


  CHAPTER XXV.

  GUN-CARRIAGE--IRON SHIPS--HYDRAULIC CRANE--ICE MAKING--DRAINAGE
  OF HOLLAND--CHAIN-PUMP--OPEN-TOP CYLINDER--HAYLE HARBOUR--PATENT
  RIGHTS--PETITION TO PARLIAMENT.

  Trevithick's description of gun-carriage and iron ship--Select
  committee--Glasgow iron-ship builders--Trevithick's comparison of
  gunpowder and steam--Cranes worked by air or water--Artificial
  cold--Liberality--Holland--Drainage--Dredging--Zuyder
  Zee--Hydraulic crane--Dutch pumping engine--Chain-pump--Haarlem
  Lake--Rhine--Windmills--Hayle Harbour--Disputed pole-engine
  patent right--Petition to Parliament, 1828--Marine boilers--Steam
  pressure--Engine duty--Lords of the Treasury refuse the
  petition--Davies Gilbert's views--Marine compound engine of 1871
  Page 284-314


  CHAPTER XXVI.

  TUBULAR BOILER--SUPERHEATING STEAM--SURFACE CONDENSER.

  Binner Downs engine, 1828--Fires around cylinder and
  steam-pipes--Saving of coal--Surface condensation at sea--Superheating
  tubes--Used steam returned to the boiler, 1828--Holland pumping
  engine--Woolf at the Consolidated Mines--Laws of steam--Power
  of heat from 1 lb. of coal--Loss of heat--Experiments at Binner
  Downs--Surface condensation--Partial surface condensation for ships
  or railways--Effect of superheating--Watt's theory doubted--Wheal
  Towan and other engines--Loss of heat--Injection-water--Surface
  condensation and superheating--Partial condensation engine--Duty
  of chain pumping engine--Surface condensation by cold water or
  air--Results of the experiment--Hayle Harbour--Condenser of copper
  tubes, 1829--Suitability for steam-ships--Proposal to erect at his own
  expense a marine engine with surface condenser and screw-propeller
  for the instruction of the Admiralty, 1830.--Sketch of tubular boiler
  and surface-air condenser--Screw draught--Preservation of heat in
  condensing by air--Comptroller of the Navy--Patent of 1831--Boiler
  within the condenser--Surface condensation by air or water--Safety
  boiler of concentric tubes--Blowing vessel for air condensation
  and draught--Tubes for distilling water--Steam pressure--Expansive
  working--Robert Stephenson's statement--'Echo' steamboat,
  1831--Bottle-neck boiler--Admiralty--Steam Users' Association--Mr.
  Alexander Crichton's boiler and surface condenser--Captain Dick and
  Captain Andrew--Captain King and the 'Echo'      Page 315-362


  CHAPTER XXVII.

  HEATING APPARATUS--MARINE STEAM-ENGINES--REFORM COLUMN.

  Ill health, 1830--Hot-house boiler--Heating rooms--Discharging
  coal-ships by steam--Hot-water stoves for France--Patent for heating
  apparatus, 1831--Marine portable engines--Boat propeller--Wheal
  Towan--Discharging coal by steam at Hayle--Proposal to the Common
  Council of London--Every vessel to carry a steam-engine--Mr. George
  Rennie--Proposal to the Admiralty--Surface condensation--Locomotives
  supplying their own feed-water--Petition in Trevithick's
  favour--Davies Gilbert's suggestion--His comparison of the Watt
  and Trevithick engines--Maudslay on Trevithick's proposals--Patent
  of 1832--Superheating steam--Cylinder placed in flue from
  boiler--Expansive steam--Tubular boiler--Water propulsion--Superheating
  and surface condensation for locomotives--Detail of engine--Proposal
  to send steamboats to Buenos Ayres--Waterwitch Company--Messrs.
  Hall and Sons--Hall's condenser--Rennie and the Admiralty--'Syria'
  steamboat--Compound engines--Watt on high-pressure steam--Trevithick
  on compound engines--Tubular boiler and variable blast-pipe--Refusal
  of Trevithick's petition to Government--Ill health--Davies
  Gilbert's statement to Spring Rice--Meeting on proposed Reform
  Column--Trevithick's description--Means of ascent and descent--Placed
  before the King--Death--Funeral--His last letter Page 363-396




ILLUSTRATIONS TO VOLUME II.


                                        PAGE

  AËRATED STEAM-BOILER                                                 7
  ROCK SPLITTING                                                      25
  STEAM THRASHING ENGINE                                              37
  AGRICULTURAL MACHINE                                                58
  WHEAL PROSPER HIGH-PRESSURE STEAM POLE-ENGINE                       70
  CYLINDRICAL HIGH-PRESSURE STEAM-BOILERS                             71
  EXPANSIVE STEAM POLE-ENGINE                                         81
  CARN BREA CASTLE                                                   147
  TREVITHICK'S DOLCOATH ENGINE OF 1816                               168
  TREVITHICK'S DOLCOATH BOILERS OF 1811                              169
  STEAM DIAGRAM                                                      185
  'LA BELLE MACHINE'                                                 190
  CARRIAGE-WHEELS                                                    207
  WINDING ENGINES                                                    208
  PENZANCE IN OLDEN TIME                                             228
  MARKET, JEW STREET, PENZANCE                                       243
  MULE TRACK FROM LIMA TO CERRO DE PASCO                             258
  MAP OF COSTA RICA MINES                                            260
  GUN-CARRIAGE                                                       285
  DUTCH PUMPING ENGINE                                               298
  MOUNT'S BAY                                                        318
  PARTIAL CONDENSATION ENGINE                                        332
  TUBULAR BOILER AND CONDENSER                                       339
  BOTTLE-NECK BOILER                                                 357
  CAPTAIN DICK AND CAPTAIN ANDREW                                    361
  HOT-WATER ROOM-WARMER                                              364
  PATENT HEATING APPARATUS                                           366
  DUCK'S-FOOT PADDLE                                                 369
  MARINE ENGINE AND BOILER                                           380
  COMPOUND MARINE ENGINE                                             385
  REFORM COLUMN IN DETAIL                                            391
  GENERAL VIEW OF REFORM COLUMN                                      393




LIFE OF TREVITHICK.




CHAPTER XVII.

VARIOUS INVENTIONS.


 "About 1804 Captain Trevithick put up in Dolcoath Mine a
 stone-crushing mill, having large cast-iron rollers, for breaking into
 small pieces the large stones of ore; it was spoken of as the first
 ever used for such a purpose; the same form of crusher is still used
 in the mines. It caused a great saving compared with breaking by a
 hand hammer."[1]

 "I saw at the Weith Mine in 1805 a portable high-pressure engine, made
 by Captain Trevithick.

 "It was called a puffer; the cylinder was in the boiler; the steam
 about 30 lbs. on the inch above the atmosphere. A wooden shed
 sheltered the engine and man.

 "The facility of manufacture and cheapness of those engines caused
 them to be much used in the mines, and also elsewhere."[2]

[Footnote 1: Recollections of the late Captain Charles Thomas, manager
of Dolcoath.]

[Footnote 2: Captain Samuel Grose's recollections.]

Mrs. Trevithick, about the time we are speaking of, accompanied
her husband through one of the Staffordshire china manufactories.
Trevithick said to the manufacturer, "You would grind your clay much
better by using my cast-iron rolls and high-pressure steam-engine." The
manufacturer begged him to accept a set of china. Mrs. Trevithick was
disappointed at hearing her husband say "No! I have only told you what
was passing in my mind."

Driving rolling-mills was among the early applications of the
high-pressure steam-engines; but pulverizing hard rock by the use
of iron rollers was a novelty: though his patent of 1802 shows the
proposed rolls driven by steam for crushing sugar-canes, yet no one had
dreamt, prior to 1804, of economy in crushing stone and clay by such a
means. The plan, however, remains in use to this day in many mines, and
is frequently spoken of under the name of quartz-crusher.

 "MR. GIDDY, COALBROOKDALE, _September 23rd, 1804_.

 "Sir,--Yours of the 13th this day came to hand. I left Wales about
 eight weeks since, and put an engine to work in Worcester, of 10-horse
 power, for driving a pair of grist-stones, and a leather-dressing
 machine, and another in Staffordshire for winding coals; each of them
 works exceedingly well.

 "From Coalbrookdale I went to Liverpool, where a founder had made two
 of them, which also worked exceedingly well; one other was nearly
 finished, and three others begun. Some Spanish merchants there saw one
 of them at work, and said that as soon as they returned to Spain they
 would send an order for twelve engines, of 12-horse power, for South
 America. In South America and the Spanish West Indies water is very
 scarce; in several places there is scarcely water for the inhabitants
 to drink, therefore there is no water for any engine. By making
 inquiry, I found that ten mules would roll as much cane in an hour as
 would produce 250 gallons of cane-juice, which they boil until the
 water is evaporated, and the sugar produced.

 "I told them that the engine-boiler might be fed with this juice,
 and by a cock in the bottom of the boiler constantly turning, and by
 taking a greater or smaller stream from it, they might make the juice
 as rich as they liked. In this process the juice would be so far on
 towards sugar, and the fire that worked the engine would cost nothing,
 because it would have taken the same quantity of fuel under the
 sugar-pans to evaporate the water, as it would in the engine-boiler.

 "The steam from the engine might be turned around the outside of the
 furnace for distilling rum, as the distilleries require but a slow
 heat.

 "I think the steam would answer a good purpose around the outside of
 the pan.

 "If this method answers, the cost of working the engine would be
 nothing, and the engine would be then working, as it were, without
 fire or water.

 "The Spaniards told me that if this plan answers, they would take a
 thousand engines for South America and the Spanish West Indies. I
 shall be very much obliged to you for your opinion on this business.
 These merchants make a trade of buying up sugar mills and pans, with
 every other thing they want from England, and exchange them with the
 Spaniards for sugar.

 "At Manchester I found two engines had been made and put to work;
 they worked very well: three more are in building. From there I went
 to Derbyshire. The great pressure-engine I expect will be at work
 before the middle of October. A foundry at Chesterfield is building a
 steam-engine as a sample; two foundries in Manchester are at full work
 on them, and one in Liverpool. There are six engines nearly finished
 at Coalbrookdale, and seven in a foundry at Bridgenorth.

 "I am making drawings for several other foundries. Any number of them
 would sell. A vast number are now being erected, and no other engine
 is erected where these are known. The engine for the West India Docks
 was neglected during my absence from the Dale, but I expect it will be
 ready to send off in ten days.

 "In about three weeks I shall be in London to set it up. It will
 please you very much, for it is a very neat and complete job, and I
 have no doubt will answer every purpose exceedingly well. At Newcastle
 I found four engines at work, and four more nearly ready; six of these
 were for winding coal, one for lifting water, and one for grinding
 corn.

 "That grinding corn was an 11-inch cylinder, driving two pair of
 5-feet stones 120 rounds per minute; ground 150 winchesters of wheat
 in twelve hours with 12 cwt. of small coal. It worked exceedingly
 well, and was a very complete engine, only the stroke was much too
 short, not more than 2 feet 6 inches, which made very much against the
 duty.

 "The other engine that was lifting water had a 5-1/2-inch diameter
 cylinder, with a 3-feet stroke, drawing 100-gallon barrels,
 twenty-four every hour, 80 yards, burning 5 cwt. of coal in
 twenty-four hours.

 "This work it did with very great ease. I believe you will find this
 an exceeding good duty for a 5-1/2-inch cylinder engine.

 "Below I send a copy of Mr. Homfray's and Mr. Wood's letters to me:--

 "Mr. Homfray's, of the 10th September.--'Our great engine goes on
 extremely well here, nothing can go better; the piston gives no
 trouble; it goes about three weeks, and we work it with blacklead and
 water; the cylinder is as bright as a looking-glass; it uses about 2
 lbs. of blacklead in a week; about once in twelve or fifteen hours we
 put a small quantity of blacklead, mixed with a little water, through
 the hole in the cylinder screw, and we never use any grease. We rolled
 last week 140 tons of iron with it, and it will roll as fast with the
 both pair of rolls, as they can bring to it.'

 "Mr. Wood's letter, September 12th.--'We are going on, as it is likely
 we always shall, in the old dog-trot way, puddling and rolling from
 the beginning of the week till the end of it. Your engine is the
 favourite engine with every man about the place, and Mr. Homfray says
 it is the best in the kingdom.'

 "I have not the smallest doubt but that I can make a piston without
 any friction or any packing whatever, that needs not to have the
 cylinder screw taken up once in seven years. It is a very simple plan,
 and will be perfectly tight; it is by restoring an equilibrium on both
 sides of the piston. I expect to see you in London soon, and then will
 give you the plan for inspection before I put it in practice.

 "I am very much obliged to you for recommending these engines in
 Cornwall, but you have not stated in what manner they are to be
 applied; whether to work pumps, or barrels, or both. They may be made
 both winding and pumping engines at the same time, if so required.

 "A rotative engine will cost more than an up-and-down-stroke, on
 account of the expense of the fly-wheel and axle. An engine capable
 of lifting 180 gallons of water per minute 20 fathoms would cost,
 when complete and at work, patent right included, about 220_l._ If
 it is a rotative engine, with a winding barrel, it will cost 270_l._
 I expect that a 7-inch cylinder would be sufficient for winding at
 Penberthy Crofts, which might have a Crank on the fly for lifting
 water in pumps, and a winding barrel on its back. This would cost
 about 170_l._; the erection of them, when on the spot, will cost
 nothing. You do not say when you intend to be in town. I hope you will
 be present when the dock-engine is set to work.

 "The engines first sent to Cornwall, must be from Coalbrookdale; then
 they will be well executed, but from Wales it would not be so.

 "You may depend on having a real good engine sent down, with
 sufficient openings given to the passages.

 "The engineer from the Dale has been lately in London, and has just
 returned; he gives a wonderful account of the engines working in
 London. There are twelve now at work there. They have well established
 their utility in different parts of the kingdom, and any number would
 sell. The founders intend to make a great number, of different sizes,
 and send them to different markets for sale, completely finished, as
 they stand.

 "You do not say anything about wheels to the engine for Penberthy
 Crofts. There are several engines here nearly finished; if they suit
 in size for Penberthy, one may be sent down in four or five weeks,
 otherwise it may be two months.

  "I am, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK.

 "Direct for me at the Talbot Inn, Coalbrookdale."

Trevithick worked hard and successfully in making his steam-engines
useful, and firmly believed that he could and would make them universal
labourers. Even the Spanish merchants, unacquainted with steam,
talked of giving an order for several engines for South America; and
their glowing account of the wide field open to him may have been
instrumental to his going to that country by making his engines
known there. His proposal to make the sugar-cane convert itself into
sugar by the use of his patent high-pressure steam-engine may be more
theoretical than practical; but many more unlikely things have come to
pass.

At that time several of his engines were at work in Wales, Worcester,
Staffordshire, Coalbrookdale, Manchester, Derbyshire, Liverpool,
Cornwall, and Newcastle-upon-Tyne. Twelve were at work in London, and
so familiar were people with them, that founders intended to construct
them of different sizes, and send them for sale at the large market or
county towns; their cost complete, ready for work, to be 200_l._, more
or less, according to size, with a range of application unlimited. His
one letter, casually written sixty-seven years ago, mentions them as
grinding corn, dressing leather, winding coal, crushing sugar-cane,
prepared to boil sugar, and distil rum; pumping water, rolling iron,
railway locomotion, portable steam fire-engine, portable steam-crane,
mine engines on wheels; so that it may almost be said he was not too
sanguine in hoping to send in 1804 a thousand of his engines to South
America, for in those cursory remarks he draws attention to no less
than thirty-six high-pressure steam-puffers at work.

The Penberthy Croft Mine portable engine could be placed on wheels or
otherwise, according to the wish of the purchaser, as though steam
locomotion was an every day occurrence in 1804.

 "CAMBORNE, _January 13th, 1811_.

 "MR. GIDDY,

 "Sir,--From calculating the quantity of blast given to a
 blast-furnace, I find a considerable quantity more of coal consumed by
 the same quantity of air in this way, than by the usual way in common
 engine chimneys. Of course the more cold air admitted to pass through
 the fire, the more heat carried to the top of the stack. Crenver
 63-inch cylinder, double-power, 8-feet stroke, with but one boiler,
 works five strokes per minute. This gives about 1600 square feet of
 steam per minute, and burns about 8 tons of coals in twenty-four
 hours. The stack for this boiler is 3-1/2 feet square, and the draught
 rises 10 feet per second, and will set white paper in a flame at the
 top of it in about a minute. Therefore, this chimney delivers 7200
 square feet of air per minute, which is four and a half times the
 quantity of heated air, at nearly four times the temperature of heat
 that there is of steam produced from the same fire, and delivered to
 the cylinder.

 "A blast-furnace that burns 100 tons of coal per week is blown by a
 5-feet diameter air-cylinder, 4-feet stroke, ten strokes per minute,
 double-power, giving about 1600 square feet of air per minute, to
 consume 100 tons of coal, besides giving a melting heat to 350 tons of
 ore and limestone.

 "Crenver engine has 7200 square feet of air to burn 56 tons of coal
 per week, which is above eight times the quantity of air used by air
 fire-places to what is used in a blast-furnace, and of course must
 carry off a great proportion of the heat to the top of the stack, that
 might be saved if the engine-fire was a blast instead of an air fire.

 "But suppose the idea to be carried still further, by making an
 apparatus to condense and take the whole of the heat into the cylinder
 instead of its passing up the chimney. By having a very small boiler,
 and a blast-cylinder to blow the whole of the blast into the bottom of
 the boiler, under a cylinder full of small holes under the water, to
 make the heated air give all its heat to the water.

 [Illustration]

 "The furnace must be made in a tight cast-iron cylinder. Both the
 fire-door and the hole through which the blast enters must be quite
 tight, as the pressure will be as strong in the fire-place as in the
 boiler. The whole of the air driven into the fire-place, with all
 the steam raised by its passage up through the water in the boiler,
 must go into the cylinder. There will also be the advantage of the
 expansion of the air by the heat over and above what it was when taken
 cold into the blast-cylinder.

 "From the great quantity of coal burnt in blast-furnaces you will find
 that a very small blast-cylinder would work a 63-inch cylinder double.
 If there is as much heat in a square foot of air as in steam of the
 same temperature, the saving will be beyond all conception; but for my
 own part I cannot calculate from theory what the advantages will be,
 if any, and for that reason, before I drop or condemn the idea, I must
 request you will have the goodness, when you have an hour to spare, to
 turn your thoughts to this subject, and inform me of your sentiments
 on it.

 "Perhaps it is like many other wild fancies that fly through the
 brain, but I did not like to let it go unnoticed without first getting
 your opinion. I hope you will excuse me for so often troubling you.

 "St. Ives plans will be delivered to them on Tuesday, when I expect
 they will be forwarded to you.

 "I hear there is a good course of ore in the adit end at Wheat
 Providence Mine.

 "A Mr. Sheffield, of Cumberland, writes to Mr. Gould that he has
 turned idle his air-furnaces, and smelted his ores by a blast near a
 year since.

 "His furnace is but 10 feet high and 4 feet diameter, and it melts 28
 tons of ore, of from 4 to 5 in the 100 per week, and makes a regel of
 from 65 to 70 in the 100, and answers beyond what we calculated for
 them.

 "Suppose a furnace 20 feet high and 4 feet diameter, it would smelt
 eight times the quantity of his, which would be near 900 tons per
 month, or nearly double the quantity raised by any one mine in the
 country. The expense of the ... would be very trifling.

 "To-morrow Dolcoath account will be held, when I expect to have orders
 to begin to erect a furnace on the spot.

 "This trial of Mr. Sheffield's has put it out of my power to get a
 patent, and now I do not know how to get paid.

 "I should be content with 5 per cent. on the profits gained by this
 plan, and would conduct the business for the mines without salary.
 Should you chance to fall on the subject with his Lordship, be pleased
 to mention something about the mode of my payment, as his Lordship is
 by far the properest person to begin with about my pay, for after his
 Lordship has agreed to the sum, and Dolcoath Mine the first to try
 the experiment, I think all the county will give way to what he might
 propose. But I wish something to be fixed on before all the agents in
 the mines know how to be smelters themselves, after which I expect no
 favour, unless first arranged.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK."

How great was the practical insight his genius gave him, and how
imperfectly his followers have acted on this advice given sixty years
ago!

The chimney that at its top would ignite paper, threw to waste four and
a half times more heated air than was requisite to supply the quantity
of heat which passed through the working cylinder in steam, and at
a temperature nearly four times greater than the temperature of the
steam. It needs only to observe the burnt appearance of a steamboat
funnel of the present day to know how wasteful we still are, or how
very ignorant of improved methods of economizing fuel.

To prevent this waste of heat up the chimney be proposed to do away
with the chimney altogether; the fire-place was to be a close one,
having a blast under the fire-bars of a strength sufficient to force
the air, heated by its passage through the fire, direct through a small
valve into the water in the boiler, by which means all the heat given
by ignition would pass into the steam, and his steam-puffer become an
aërated steam-engine.

From the following it appears that this plan of Trevithick's is now
coming into use as something quite new:--

"In your last impression, under the head of 'Air and Steam combined,
as a Motive Power,' you state 'the invention was described to be that
of Mr. Warsop, but we have recently heard that a few years back (1865)
the same invention had been protected in an earlier patent than Mr.
Warsop's, by Mr. Bell Galloway.'"[3]

Trevithick thought of patenting a plan for reducing copper ore by the
use of a blast, in preference to the usual air-furnace and chimney,
but something similar had been tried by Mr. Gould, and he therefore
proposed to erect a blast-furnace in Dolcoath Mine, receiving a portion
of the saving of fuel as his remuneration. Such a furnace worked there
for many years, until copper smelting was removed from Cornwall to
Wales. The plans for a breakwater at St. Ives were for an undertaking
that has since been in many hands, but without success, except perhaps
for the convenient making of members of Parliament. Some slight
progress has been made by engineers and contractors, but vessels are
not willingly taken to the port, and ratepayers grumble at unprofitable
harbour taxes.

 "LONDON, _January 20th, 1811_.

 "DEAR TREVITHICK,

 "I have not lost any time in mentioning your wishes respecting a
 compensation for the plan of smelting copper to Lord Dedunstanville,
 who intends mentioning the affair in his next letter to Mr. Reynolds.
 Lord Dedunstanville wishes you extremely well, but it is impossible
 for him to settle anything apart from the adventurers.

 [Footnote 3: See the 'Mechanics' Magazine,' June 3rd, 1870.]

 "I am very sorry that anyone should have executed the plan of reducing
 copper ore by a blast-furnace before you had put into practice the
 idea suggested to me ten years ago. It ascertains, however, that the
 contrivance will succeed, although you are certainly reduced to ask
 moderate terms, and I know not what can be more moderate than those
 you have asked, except that I would recommend some limit as to time.

 "The plan you suggest for an engine on a new construction is, I fear,
 very doubtful.

 "According to the data furnished to me, the air in the blast would be
 to that in a common fire-place as 6-1/4 to 1 very nearly, provided
 their densities were the same; but you have measured one entering
 the furnace at the common temperature, and the other going to the
 stack so hot as to set on fire a piece of paper held at the top.
 Thus the increase of temperature that augments the elasticity of a
 fluid confined, would expand it in the same degree. It is therefore
 uncertain from these statements which furnace consumes the greater
 quantity of air. I apprehend the general principles of an engine
 worked by hot air, through the medium of a blast, would be as
 follows:--

 "Let any quantity of air be driven into a furnace with the pressure
 of an atmosphere, and let it be there expanded ten times. It should
 then be taken off ten times as quick, but in that case no power
 whatever would be produced, so the external atmosphere would balance
 the internal. Now, let the blast be two atmospheres strong, and let
 them be expanded ten times, and be taken off ten times as fast, each
 stroke will be opposed by one, equal in all to ten; subtract two for
 the blast, there remain eight.

 "But air so hot would burn every vegetable or animal substance, and
 such a furnace I suppose could scarcely be kept air-*tight. If the
 heated air is made to act on water, then it becomes a mere question
 of how much absolute heat is given out by the fuel, and whether that
 excess is more than sufficient to compensate the burden of the blast;
 for the water will absorb an immense quantity of heat in changing
 itself into steam, and thus reduce the force of the air as to make it
 almost impossible for that addition to add so much power as the blast
 takes away.

 "I have, therefore, no hesitation in saying that this plan will
 certainly not do. Write to me by all means whenever anything strikes
 you, and you may always depend on having my best advice.

  "I am, dear Sir,
  "Ever most truly yours,
  "DAVIES GIDDY."

Trevithick saw without apparent reasoning, while his friend's
reasonings failed to make plain the full bearing of the questions, and
so cramped the position as to make a change of front difficult--an
operation in which Trevithick excelled. We learn, however, that in 1801
he suggested a blast in copper-ore furnaces, and in 1811 was on the
verge of a discovery that has since revolutionized the iron-smelter's
art by the use of hot blast. Wasted heat from a blast-furnace 10 feet
high led him to the conclusion that by doubling the height of the
furnace, enabling the cold mineral thrown in at the top to take up the
heat wasted through the top of the low furnace, seven-eighths of the
coal would be saved. His idea of sending blast through the furnace of
his steam-boiler to economize heat could have been readily applied to
the iron furnace, and we should have had the modern hot-blast iron
furnaces.

 [Rough draft.]

 "CAMBORNE, _March 5th, 1812_.

 "GENTLEMEN,

 "Your favour of the 15th February, with a sketch of your brewery, I
 have received; and from which I find the head of water is 30 feet
 above the brewery, which makes it difficult to erect the chain and
 buckets so as to take advantage of the whole height of water; and as
 the stream is so very small, it will not admit of losing any part of
 the power.

 "To erect a machine so high, to engage the whole fall, would be,
 I fear, more expense than the power you would get would warrant;
 therefore I would recommend it to be made use of in a cylinder, in the
 same way as we use falls of water of 200 feet in our Cornish copper
 mines. We allow one-third loss for friction and leakage in those
 machines; but your machine being so very small, the loss will exceed
 that proportion; therefore I cannot promise you above one-half of the
 real weight and fall to be performed on your machinery, and that must
 be by a well-executed machine, for a small defect would destroy the
 value of so trifling a power.

 "As there is no expansion in water, it will be somewhat difficult to
 make the machine turn the centres with a fly-wheel, for if the valve
 shuts a little too early or too late for the turn of the crank over
 the centre, the fly-wheel's velocity must break something by confining
 the water between the piston and the bottom of the cylinder, which,
 after the valve is shut, cannot make its escape, and not having an
 elastic principle, the piston will strike as dead on the water as on a
 piece of iron, because, unless the valve is shut by the engine before
 the stroke is finished, it cannot shut at all.

 "I know persons who have attempted to put fly-wheels on
 pressure-engines of this kind, but never yet has one been made to work
 rotative. I do not see much difficulty in making an engine of this
 kind to work a crank and fly-wheel, by connecting an air-vessel with
 the cylinder to receive the pressure and contract and expand and shut
 the valves, the same as in steam-engines.

 "A machine on this plan ought to be placed as near the low level
 as possible. If I furnish you with drawings and directions for the
 executing of the work yourselves, I shall charge you fifteen guineas
 for them. If I send the machine finished, the charge will be 50_l._

 "Your objections respecting steam-engines I do not doubt are correct,
 when executed by persons who do not understand the construction of
 them. In England some persons privately erected my engine to evade
 the patent premium, but have severely paid for their saving knowledge
 by accidents and defects in their engineering ability. I have erected
 above 100 steam-engines on this principle, but never met with one
 accident or complaint against them. To prevent mischief from bad
 castings, or from the fire injuring the surface of cast iron, I make
 the boilers of wrought iron, and always prove them with a pressure of
 water, forced in equal to four times the strength of steam intended to
 be worked with.

 "Some persons have worked those engines under a pressure above 100
 lbs. on the square inch, but in general practice I do not exceed 20
 lbs., finding under this pressure the piston will stand six or eight
 weeks, and the joints remain perfect, and no risk of bursting the
 boiler, it being made of wrought iron, and proved by pressure before
 sent off; but cast-iron boilers may, by defects not discernible, and
 are very apt to break by the water being left low in the boiler,
 and if heated red hot, exploding without the smallest notice; but
 wrought-iron boilers, when defective, give way only partially, without
 injury to anyone. With respect to the erecting and management of the
 engine, you need not have an engineer, for any common tradesman can do
 this from the drawings and directions sent with the engine; for, as I
 before informed you, farmers and their labourers set up and keep in
 order the thrashing-machine engines without my going on the spot or
 sending any person to assist them. I never saw a steam-engine rolling
 malt, therefore cannot judge the quantity the engine would roll, only
 by a comparison with horse labour, against the consumption of coal,
 which will be in some cases as about 42 lbs. to one horse; but where
 great speed is required in the machine, the coal will be less, as
 steam-engines make more revolutions in a minute than horse mills,
 therefore the work is done with less friction.

 "I have several times applied the steam, after it has worked the
 engine, to boil water and other purposes, with as good effect as if
 the engine had not been there, therefore the work of the engine will
 be a clear profit.

 "You say about a 1-horse engine. The boiler would be so small that it
 would not be worth applying that steam to any other purpose, as any
 large quantity of water would be but slowly heated.

 "I find that it does not answer either the purpose of the vendor
 or the user of an engine, to make less than a 2-horse power, as
 the expense on a very small engine is nearly as much as one of the
 power I use for thrashing, those being only 80_l._, and a 2-horse is
 60_l._ Respecting the mashing with steam, I never before heard of it,
 but from the theory of the plan I think it cannot fail to answer a
 far better purpose than any other that can possibly be applied for
 extracting the essence of the malt. However, should it not answer your
 purpose, it is only the loss of the expense of a few yards of 1-inch
 lead pipe.

 "In an engine of the size used for thrashing, if the fire is kept
 brisk, it will boil, by the steam sent into a separate vessel, near
 300 gallons of water per hour.

 "The room required to work in is about 7 feet diameter, and 12 feet
 high. It would be useless to put you to the expense of drawings, until
 you have made up your minds on what you intend to have done.

  "I remain, Gentlemen,
  "Your most obedient humble servant,
  "RICHARD TREVITHICK.

  "To ROBINSON AND BUCHANAN, Brewers,
  "_Londonderry, Ireland_."

Engineers of the present day do not volunteer such general information
without charge, or give such a variety of practical mechanism
slightly but clearly described, and principles reduced to practice.
An endless chain with buckets is a form of water-wheel not then in
use. A water-pressure engine for so small a quantity of water, with
a fall of about 30 feet, would cause a loss of 50 per cent. from
friction and small defects. The non-elastic character of water made it
unsuitable for a machine requiring a fly-wheel. Air-vessels should be
used to lessen the rigidity of water. Cast-iron boilers dangerous.
Wrought-iron boilers to be tested with a water pressure four times as
great as the proposed working steam pressure. A steam pressure of 20
lbs. to the inch most suitable for engines in charge of inexperienced
persons. The brewers' mash tub to be heated by the waste or surplus
steam.

 [Rough draft.]

 "CAMBORNE, _December 5th_, 1812.

 "GENTLEMEN,

 "I have yours of the 20th November. The letter you directed for
 Truro never came to hand. I find by your letter that you have been
 trying to put into practice the hints I gave you about the chain and
 buckets, and that you expect it will answer if properly executed.
 You are not the first that has picked up my hints, and stuck fast in
 their execution. I make it a rule never to send a drawing until I
 have received my fee, and when you remit to me fifteen guineas I will
 furnish you with proper drawings and directions to enable you to make
 and erect the machine.

  "I remain, Gentlemen,
  "Your very humble servant,
  "RICHARD TREVITHICK.

  "ROBINSON AND BUCHANAN, Brewers,
  "_Londonderry_."

What a pocket encyclopædia of inventions! from which, as by stealth,
Robinson and Buchanan selected the least applicable, declining a
suitable steam-engine at a very small cost, rather than pay an engineer
for his opinion.

 [Rough draft.]

 "CAMBORNE, _April 26th_, 1812.

 "SIR CHARLES HAWKINS, Bart.,

 "Sir,--I have received yours of the 7th, respecting the small
 breakwater at St. Ives. As far as I can judge from a rough
 calculation, I think it an undertaking likely to pay well; but as
 you wished me not to mention anything about your intentions, and not
 receiving your orders to make a minute inquiry and estimate, I cannot
 answer your letter so fully as I should wish, fearing that giving a
 random and imperfect statement might be apt to lead you into errors,
 and also make me look simple. If an engineer were employed to survey
 and estimate after me, every information in my power is at your
 service; therefore be pleased to state particularly what information
 you wish, and I will attend to the business and answer your questions
 as early as possible.

 "I have received a letter from Sir John Sinclair requesting correct
 drawings and statements of the thrashing engine to be forwarded to the
 President of the Board of Agriculture, which I shall attend to. He
 also says that he has sent my letter to the Navy Board, in hopes that
 the experiment of propelling vessels by steam may be tried under its
 sanction and expense.

 "Perhaps it might be proper to wait the answer of the Navy Board
 before writing to Mr. Praed about propelling the canal boats. I am
 very much obliged to you for writing to Captain Gundry, about the
 Wheal Friendship engine. I expect to have a portable steam-whim and
 stamps at work at my own expense in a few days, which will prove for
 itself its utility; that being the only way to introduce new things. I
 would be very much obliged to you to say if Mr. Halse is to pay me for
 my past attendance at St. Ives about the breakwater. Enclosed you have
 a letter to Sir John Sinclair, unsealed for your inspection, which, if
 you approve of, please to forward.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK."

Trevithick's skill did not prevent his being reasonably modest,
or cause him to be envious of others; neither did his dear-bought
experience, that one's own pocket must pay for making public one's own
inventions, prevent his again soliciting the assistance of persons of
influence, though it does not seem that Mr. Praed helped forward the
screw-propeller, or that Sir John Sinclair gave direct help, though
he probably made known the high-pressure steam-engine to the marine
experimenters on the Clyde.

 [Rough draft.]

 "MR. RASTRICK,

 "CAMBORNE, _December 7th, 1812_.

 "Sir,--I have been waiting your answer to my last, and especially that
 part respecting the West India engine, as I have not nor could not
 answer their letter to me without first hearing from you; therefore
 must beg you will be so good as to answer me by return of post on that
 subject. If they get impatient about the time, and refuse to take the
 engine, I have no doubt the Plymouth people will take it and several
 others; but I very much wish to send one to the West Indies, as there
 is a large field open there for engines of this kind. I have received
 an order for a thrashing engine for Lord de Dunstanville, of Tehidy;
 and as I wish those thrashing engines to be known through the country,
 I intend to take one of the engines ordered for Padstow and send it
 to Tehidy. One of the Padstow farmers can wait until you make another
 for him. Therefore I would thank you to send the first finished by
 ship from Bristol for Portreath or Hayle. Send a drum with everything
 complete, of which you are a better judge than I. Probably about 3
 feet in diameter and 3-1/2 feet long will be sufficient.

 "There must be a fly-wheel with a notch to carry the rope, and also a
 small notch-wheel on the drum-axle. I think 6-1/2 feet diameter for
 the fly, and 9-1/2 inches diameter for the small wheel, will give
 speed enough to the drum. Mind to cast a lump, or screw on a balance,
 of about 1 cwt., on one side of the fly-wheel. There must be two
 stands on the boiler, and a crank-axle, or otherwise a crank-pin, in
 the fly-wheel, whichever you please; with a shaft 3 feet long with a
 carriage.

 "The engine is to stand in a room under the barn, about 7-1/2 feet
 high, 7 feet wide, and 14 feet long. The fly-wheel will stand across
 the narrow way of the room. The rope will go up through the floor, and
 the drum be shifted by a screw, horizontally, on the barn floor, so
 as to tighten the rope. I shall put down the top of the boiler level
 with the surface, with an arched way to the fire and ash-pit under
 ground, to prevent the chance of fire, which the farmers are very much
 afraid of. I send you a sketch showing how it is to stand.

 "I do not bind you to the size of the drum or wheels, only the room
 that the fly-wheel works in is but 7 feet wide.

 "Now to Mr. Richards' mill.

 "Query 1st.--The length of the piston, and the small variation that
 the beam will give it, is so trifling that it will not be felt.

 "The cylinders that have been working on their sides for seven years
 past, are now working as well as any engine with upright cylinders,
 which is a proof that the little rubbing is of no consequence.

 "Query 2nd.--The passage in the cock is equal to the passage we
 make in our large engines, which is only one-fortieth part of the
 piston; and as we shall work with high steam, we do not mind the
 pressing through the steam-passage; and as the steam will be very
 much expanded, it will not be felt in the passage to the condenser. I
 know where we have removed cylinders and put larger ones on the same
 nozzles and condensing work, and the engines did good duty.

 "Query 3rd.--I find by experience that if you give double the quantity
 of injection to an engine one stroke, and none the other, that the
 quicksilver in the gauge will stand nearly the same; the cold sides of
 the condenser are sufficient to work an engine a great many strokes
 without any injection.

 "Query 4th.--You may put a hanging to the air-pump bucket, and
 foot-valve; either that or a rising one will do very well, but I think
 the rising cover and wood face on the top, best.

 "Query 5th.--The air-pump bucket is large enough. At Wheal Alfred they
 have a 64-inch cylinder; the air-pump is 20 inches, and the stroke
 is half that of the engine. They were afraid that it was too small;
 they then put another of 14 inches by the side of the first, the same
 stroke. The quicksilver tube stands as high with the one 20-inch
 bucket as with the two buckets; the engine works best with the one
 bucket. I have found by experience that size to be sufficient, and
 (especially in an engine that works quickly) make the cistern high
 enough to cover the condensing work well with water.

 "Query 6th.--My reason for making the forcing pump with duck-valves
 is, because they do not bum like the others, and we find them seldom
 out of repair; but make it whichever way you think best, and work it
 in any way you like.

 "Query 7th.--I mean by 3/4 expansive, that the steam is to be shut off
 from the cylinder when the piston has moved up from the bottom one
 quarter of its stroke. Make the cam to your own mind.

 "Query 8th.--I do not think the engine will require a heavier
 fly-wheel, as the stones will act as a fly, and the power, though so
 very irregular, will be so sudden in its changes, that the speed of
 the machinery will not let it be felt. If you make a crank, you may
 make the fly-wheel 3 or 4 feet more in diameter. But if with a pin in
 the fly-wheel, the beam would come down on the top of it; therefore, I
 think it will be better to put a crank, and put the fly-wheel in the
 middle of the shaft.

 "Query 9th.--The steam will be raised to 25 lbs. to the inch above the
 atmosphere, or 40 lbs. to the inch on a vacuum; but I think you need
 not calculate for much more strength on that account. It is not the
 power that breaks the machinery, but bangs, and not the uniform weight
 that this will give.

 "Query 10th.--Twenty strokes per minute I propose, which I think a
 fair speed.

 "Query 11th.--The fire-bars must be of wrought iron; we find them
 answer much better than cast iron. Let them be 5/8ths of an inch from
 bar to bar, 1 inch thick at the top, 3/8ths of an inch at the bottom,
 2 inches deep, 4 feet long, with bits on them at the ends, to prevent
 their getting too close together. I find the nearer the fire is to the
 door, the better and handier it is to work. All the large engines are
 in this way, and we do not find the door or front plate get hot, as
 they are lined with brick. Cast the door with a rib to hold a brick on
 its edge. Tube, 2 feet 9 inches by 1 foot 11 inches; manhole, 15 by 10
 inches.

 "Query 12th.--A governor will be required; perhaps as good a place
 as any for it, out of the way, will be on the cast iron that carries
 the beam; you may turn the fly-wheel whichever way you please. If
 this engine is worked with steam of 25 lbs. to the inch above the
 atmosphere, and the steam shut off at one-twentieth part of the
 ascending stroke of the piston, the power will be as three is to two
 of Boulton and Watt's single engines.

 "Only two pairs of stones for the present, but calculate those stones
 to stand in such a way that another pair may be placed, on a future
 day, if wanted. I have not seen Mr. Richards lately. I wish you to
 write a form of an order, in your next, such as you wish, and I will
 get him to write to you accordingly. Put the engine and drum for Lord
 de Dunstanville out of hand neat and well, as it will be well paid
 for; and make the stands, &c., in your own way.

 "RD. TREVITHICK."

Mr. Richards' flour-mill engine may claim to be the first practical
smoke-burner: keeping the fire much thinner at the inner end of the
grate-bars than at the fire-door end of the grate, allowed of the
freer passage of air through the thinner layer of coal, near the
fire-*bridge, causing the combustion of the passing gas. This idea has,
since the date of Trevithick's letter, led to several smoke-burning
patents. The boiler fire-tube was oval, 2 feet 9 inches by 1 foot 11
inches. The open-topped cylinder was supplied with a heavy and deep
piston serving as a counterweight, and also as a guide in the cylinder
for correcting the angle of the connecting rod. Experience had taught
him that the cold sides of the condenser were sufficient to work an
engine a great many strokes without a supply of injection; and he had
already used high-pressure steam of 25 lbs. to the inch above the
atmosphere, cut off from the cylinder when the piston had performed
one quarter of its course: thus both these things were as first steps
leading to the modern expansive steam-engine and surface condensation.

The simplicity of the engine is remarkable--a high-pressure, expansive,
condensing engine, worked by a single four-way cock, without
cylinder-cover, or parallel motion.

The low first cost, and non-liability to derangement, were always
kept in view; and his confirmed experience in the satisfactory
working of horizontal cylinders prior to 1812 illustrates their
extended application; for at that time scarcely any other engineer had
constructed other than upright cylinder engines. No detail escaped his
observant gaze. The fire-bars were to be 2 inches deep, 1 inch thick at
the top edge, tapered to 3/4ths of an inch at the bottom, giving the
required strength, with free room for air, which in its passage cooled
the bar, carrying the heat into the fire. Years before and after that
period the fire-bar in common use by thoughtless people was a square
iron bar that was always burning and bending.

The letter is descriptive of the high-pressure steam-engine in the
sixteenth year of its age; and its expansive steam, made practical
by Trevithick's high-pressure boilers. This engine only took steam
during the first quarter of its stroke, the remaining three-quarters
were by the expansion. Had it taken steam only during one-twentieth of
its stroke, it would have been more powerful than Boulton and Watt's
low-pressure steam vacuum engine of the same size.

 [Rough draft.]

 "SIR,

 "CAMBORNE, _November 8th, 1812_.

 "I have your favour of the 3rd inst., informing me that Messrs. Fox
 and Williams have engaged to quarry the stone for e breakwater at
 Plymouth, but does not say whether you hold any share with them in
 the contract or not. Therefore I cannot understand from your letter
 whether you wish to see an engine fitted to the purpose of the
 breakwater, or for pumping the water from the foundations of the
 Exeter Bridge. Please to inform me which of the two purposes you wish
 to see the engine calculated for, and about what time you think you
 shall want it, and I will get one finished suitable to the purpose you
 intend it for.

  "Yours, &c.,
  "R. T.

  "JAS. GREEN, ESQ., _St. David's Hill, Exeter_.

 "N.B.--To what extent have Messrs. Fox engaged, and what parts of the
 work do they perform? I think more good might be done by loading,
 carrying, and discharging, than by quarrying only."

Trevithick was equally ready with the application of steam-power either
for pumping of water or for boring and removing rock. The use of
chisels and rock-breakers in the Thames in 1803[4] had prepared the way
for the more perfect engine for boring, lifting, and carrying rock from
the quarries to its destination at the Plymouth Breakwater in 1812.[5]

[Footnote 4: See Stonebreaker of 1803, vol. i., p. 239.]

[Footnote 5: See Steam-crane, vol. i., pp. 162, 274.]

 "SIR,

 "106, HOLBORN HILL, _November 26th, 1812_.

 "I am in receipt of yours of the 22nd inst. Mr. Giddy informs me that
 Mr. Fox and Mr. Williams are to have 2_s._ 6_d._ per ton for making
 the breakwater at Plymouth, and he considers that they can do it for
 2_s._, which he thought would give them 50,000_l._ profit. If you meet
 those gentlemen, I have to caution you not to LEARN THEM
 anything until you make a bargain, as I know Mr. Williams will
 endeavour to learn all he can and then you may go whistle.

 "If 6_d._ per ton will give 50,000_l._ profit, a halfpenny per ton
 would give upwards of 4000_l._ Would they agree to give you that for
 your labour only? However, this will depend in a great measure on
 the time it will take in doing. If it takes eight years it would be
 500_l._ a year for you (according to Mr. Giddy's calculation).

  "Your well-wisher,
  "HENRY HARVEY.

  "MR. RD. TREVITHICK, _Camborne_."

Mr. Harvey knew Trevithick's weakness in money matters. Rennie had been
employed to report on the proposed Plymouth Breakwater, and in 1811 was
desired by Lord Melville, the head of the Admiralty, to proceed with
the work. "The price paid in 1812 for taking and depositing rubble in
the breakwater was 2_s._ 9_d._ per ton; it was afterwards reduced to
1_s._ per ton. A piece of ground was purchased from the Duke of Bedford
at Oreston, up the Catwater, containing 25 acres of limestone, well
adapted for the purposes of the work; and steps were taken to open out
the quarry, to lay down railways to the wharves, to erect cranes."[6]
The idea of the plan to be followed in conveying stone with greater
economy and dispatch than was contemplated by Rennie, originated with
Trevithick, while the former received the credit and the pay, as he
before had done with the steam-dredger.

[Footnote 6: 'Lives of the Engineers,' by Smiles, vol. ii., p. 260.]

 [Rough draft.]

 "MR. FOX Jun.,

 "CAMBORNE, _January 29th, 1813_.

 "Sir,--Since I was at Roskrow I have been making trial on boring
 lumps of Plymouth limestone at Hayle Foundry, and find that I can
 bore holes five times as fast with a borer turned round than by a
 blow or jumping-down in the usual way, and the edge of the boring bit
 was scarcely worn or injured by grinding against the stone, as might
 have been expected. I think the engine that is preparing for this
 purpose will bore ten holes of 2-1/2 inches in diameter 4 feet deep
 per hour. Now suppose the engine to stand on the top of the cliff, or
 on any level surface, and a row of holes bored, 4 feet in from the
 edge of the cliff, 4 feet deep, and about 12 inches from hole to hole
 for the width of the piece to be brought down at one time, and wedges
 driven into the holes to split the rock in the same way as they cleave
 moorstone, only instead of holes 4 inches deep, which will cleave a
 moorstone rock 10 feet deep when the holes are 14 or 15 inches apart,
 the holes in limestone must go as deep as you intend to cleave out
 each stope, otherwise the rock will cleave in an oblique direction,
 because detached moorstone rocks have nothing to hold them at the
 bottom, and split down the whole depth of the rock. In carrying down a
 large piece of solid ground the bottom will always be fast, therefore
 unless it is wedged hard at the bottom of the hole the stope cannot
 be carried down square. In a hole 2-1/2 inches diameter and 4 feet
 deep put in two pieces of iron, one on each side of the hole, having a
 rounded back, then put a wedge between the two pieces, which might be
 made thus, if required to wedge tighter at the bottom of the hole than
 at the top.

 [Illustration]

 "If this plan answers, the whole of the stones would be fit for
 service, even for building, and would all be nearly of the same size
 and figure. Each piece would be easily removed from the spot by an
 engine on a carriage working a crane, which would place them into the
 ship's hold at once. It would all stand on a plain surface, and might
 be had in one, two, three, or four tons in a stone, as might best
 suit the purpose, which would make the work from beginning to end one
 uniform piece. Steam machinery would accomplish more than nine-tenths
 of all the work, besides saving the expense of all the powder. I find
 that limestone will split much easier than moorstone, and I think that
 a very great saving in expense and time may be made if the plan is
 adopted.

 "Please to think of these hints and write me when and where I may
 see you to consult on the best method of making the tools for this
 purpose before I set the workmen to make them. Any day will suit me,
 except Monday, the 8th of February. The sooner the better, as I cannot
 set to work to make the tools until we have arranged the plan.

  "I am, Sir,
  "Your humble servant,
  "RD. T."

The successful completion of the Mont Cenis Tunnel in 1871 was mainly
due to an ingenious application of combined mechanical force to boring
tools, before limited to man's strength; but the applied principle
existed sixty years ago, and though not so perfect in detail, yet more
comprehensive. Trevithick's high-pressure steam boring engine enabled
him to penetrate the rock five times as fast as the quarryman's power.
Ten holes, 2-1/2 inches in diameter, 4 feet deep, could be bored in an
hour, and he sagaciously suggested that in quarrying the limestone for
the breakwater, a row of holes should be bored by his engine 4 feet
in from the face of the rock, 2-1/2 inches in diameter, 4 feet deep,
and 12 inches apart; and by dropping into each hole two half-round
pieces of iron, to be driven asunder by a steel wedge, large blocks
would be forced off without the use of gunpowder. The high-pressure
steam-puffer having bored the stone, moved itself toward the broken
mass, lifted it into waggons, and again changing its powers from
steam-crane to steam-locomotive, conveyed it to the port, and lifted
it into the ship's hold. The whole operation was thus aptly described
by the inventor, who then counted on contracting for the breakwater
work:--"Steam machinery will accomplish more than nine-tenths of all
the work, besides saving the expense of all the gunpowder."

 [Rough draft.]

 "MR. ROBERT FOX, Jun.,

 "CAMBORNE, _February 4th, 1813_.

 "Sir,--Since I was with you at Falmouth I have made a trial of boring
 limestone, and find that the men will bore a hole 1-1/2 inch in
 diameter 1 inch deep in every minute, with a weight of 500 lbs. on the
 bit. I had no lump more than 12 inches deep; but to that depth I found
 that having a flat stem to the bit of the same width as the diameter
 of the hole, twisted like a screw, completely discharged the powdered
 limestone from the bottom of the hole without the least inconvenience.

 "From the time the two men were employed boring a hole 12 inches deep,
 I am convinced to a certainty that the engine at Hayle will bore as
 many holes in one day as will be sufficient to split above 100 tons of
 limestone, and would draw that 100 tons of stone from the spot and put
 them into the ship's hold in one other day. The engine would burn in
 two days 15 bushels of coal, four men would be sufficient to attend on
 the engine, cleave the stone, and put it into the ship's hold. I think
 it would not amount to above 9_d._ per ton, every expense included,
 but say 1s., which I am certain it will not amount to. Perhaps it may
 not be amiss to withhold the method of executing this work until the
 partners have more fully arranged with me the agreement as to what I
 was to receive for carrying the plan into execution. I do not wish
 that anyone but your father should be made acquainted with the plan,
 and have no doubt he will have sufficient confidence in the scheme to
 adopt it. I shall be glad to hear from you soon, as I intend to go to
 Padstow in a few days and shall not return under a fortnight.

  "Your humble servant,
  "RD. TREVITHICK.

 "N.B.--I this day received a letter from Mr. Gould, requesting to know
 what the expense of an engine and apparatus would be for clearing
 Falmouth Harbour, which I have sent by the post."[7]

[Footnote 7: See letter, 4th February, 1813, vol. i., p. 248.]

It had been and still is the custom to bore rock either with a long
and heavy jumper-chisel, lifted a foot or two, and falling by its own
weight, pounding to powder a portion of the rock, or by the use of a
much smaller chisel called a borer, struck by a hammer. Trevithick
having made his steam-engine perform those jumper and borer movements,
turned his attention to the improvement of the borer, and found that
a revolving bit was more suitable for drilling limestone than the
borer-chisel. The powdered stone was removed from the hole by giving
a screw form to the stem of the bit. Many years afterwards precisely
similar bits for boring wood were patented as new things, and are
still used. Within five months of his first communication with the
contractors for the Plymouth Breakwater he had designed and made an
engine to bore, lift, and convey to the ship's hold 50 tons of stone
daily at less than half the cost Rennie was then paying for it.

 [Rough draft.]

 "SIR,

 "CAMBORNE, _February 4th, 1813_.

 "I have your letter of the 31st January requesting to know the time
 in which the engine will be ready for the bridge at Exeter, and also
 about giving an additional power to it.

 "The engine shall be ready in six weeks from the end of January,
 and shall be capable of lifting the 10-inch bucket you have ordered
 instead of the 9-inch before proposed, which was to have delivered 500
 gallons of water 12 feet high per minute; but now the engine shall
 be made to lift in the same proportion as a 9-inch is to a 10-inch
 bucket, which will be 617 gallons of water per minute instead of 500
 gallons, as was before agreed on, and I shall charge you accordingly.
 I observe that you have ordered the pump, and from the description
 you give of it, I think it will answer very well. If you wish a
 perpendicular cylinder instead of a horizontal, I can construct it in
 that way, but it will not be so convenient for a portable engine. I
 have now engines with horizontal cylinders at work above ten years,
 and find them answer equally as well as a perpendicular cylinder.

  "I remain, Sir,
  "Your very humble servant,
  "RICHD. TREVITHICK.

  "JAS. GREEN, Esq., _Exeter_."

Engineers nowaday are not in the habit of designing and constructing a
steam-engine in six weeks, or willing to alter the agreed form from the
horizontal to the vertical without charge.

 [Rough draft.]

 "Mr. Robert Fox, jun., informed me the other day that you had the sole
 direction of the work at Plymouth. Had I known it at the time you
 were at Scorier I should have communicated to you my ideas relating
 to the application of machinery there; but until a few days since I
 had an idea that the young Mr. Fox was about to take an active part
 in the management, which I now find was never his intention, only he
 very much wishes to have an experiment tried to see to what extent
 an engine was capable of performing as against men. An engine is now
 preparing for that purpose."


 "SIR,

 "CAMBORNE, _February 24th, 1813_.

 "On my return from Padstow this evening, where I have been for the
 last fortnight, I found your letter of the 11th inst. respecting the
 getting an apparatus ready for the Plymouth undertaking. Before I set
 about it I wish to see you and Mr. Fox, and will call any day you may
 appoint. Waiting your reply,

  "I remain, Sir,
  "Your very humble servant,
  "R. TREVITHICK.

  "MR. ROBERT FOX, Jun., _Falmouth_"

After three months of experimental scheming, without a thought of
keeping his inventions secret, Trevithick for a moment became worldly
wise, and asked for a written agreement before sending his locomotive
boring engine to the breakwater.

 [Rough draft.]

 "MR. FOX,

 "CAMBORNE, _14th March, 1814_.

 "Sir,--I expect to be called to London immediately after the end of
 this month. The engine with the boring apparatus for Plymouth remains
 at Redruth. I very much wish to see you on that business before I
 leave home, and would be much obliged by your dropping me a note by
 post, saying what day it would be convenient for me to wait on you.

 "R. T."

The rock-boring machine was completed, and reached the breakwater two
months after his interview with the Foxes, who were prominent in the
quarrying work. "The engine for Plymouth will be put to break the
ground as soon as I can find time to go up there."[8] It was impossible
for any one man, single-handed, to make perfect such numerous practical
inventions as were undertaken by Trevithick at that time. His letter
of a few months before[9] reveals the facility with which he moulded
the steam-engine to his requirements. "The ploughing engine that I sent
you a drawing for, after being used for that purpose, was to have been
sent to Exeter for pumping water. I have been obliged to take the small
portable engine from Wheal Alfred Mine, and have a new apparatus fitted
to it for Plymouth Breakwater. A small engine which I had at work at a
mine I have been obliged to send to the farmers for thrashing." Messrs.
Fox would probably require many engines for the Plymouth Breakwater,
having engaged with Government to deliver three million tons of stone;
and to prevent delay, the boring apparatus was applied to an engine
made for another purpose, while drawings for a new and more suitable
engine for boring stone were sent to Mr. Rastrick.

[Footnote 8: Trevithick's letter, May 20, 1813, chap. xxi.]

[Footnote 9: See letter to Mr. Rastrick, January 26, 1813, chap. xviii.]

He engaged that an engine should bore holes to split 100 tons of
limestone a day; and that on the following day it should, as a
locomotive and steam-crane, load that quantity in waggons, convey it
from the quarry to the port of shipment, and then by steam-crane place
it in the hold of a vessel. The whole of the work to be done by 11
cwt. of coal and four men. The gross cost would be 1_s._ per ton for
breaking and removing, though at that time Mr. Rennie was paying 2_s._
9_d._ a ton, which in after years was reduced to 1_s._, just what
Trevithick said was a fair price.

While this ready application of the high-pressure steam-engine was
going on in England, it had also extended to, and was coining money in
the Mint at Lima, where Trevithick contemplated going to look after
it, intending to land at Buenos Ayres, and make his way across the
continent of South America and the mountains of the Cordilleras as best
he could, leaving the home field he had made so fertile to be reaped by
others, and the stone-boring locomotive to be forgotten for many years.

 [Rough draft.]

 "SIRS,

 "PENZANCE, _December 9th, 1815_.

 "Your very great neglect in not writing.... Herland engine will
 work, I expect, in about fifteen days. It is a plunger of 33 inches
 diameter, 10-feet stroke, with a double packing around the top of the
 plunger-pole, in the same way as the steam is turned into the stuffing
 box of a double engine to exclude the air, only there is a small tube
 from the bottom of the boiler to the middle of the stuffing box to
 prevent the escape of steam.

 "I am sorry to find by Mr. Uville's letter that the Mint engine
 does not go well. I wish you had put the fire under the boiler and
 through the tube, as I desired you to do, in the usual way of the long
 boilers; then you might have made your fire-place as large as you
 pleased, which would have answered the purpose and worked with wood
 just as well as with coal. I always told you that the fire-place in
 the boiler was large enough for coal, but not for wood; also if you
 found that the cock did not open and shut in proper time, to make the
 gear to it work the same as the Dolcoath puffer whim-engine instead
 of the circular gear. The boiler is strong enough and large enough to
 work this engine with 30 lbs. to the inch, thirty strokes per minute.
 I hope to leave Cornwall for Lima about the end of this month, and go
 by way of Buenos Ayres, and cross over the continent of South America,
 because I cannot get any other passage. None of the South Sea whalers
 will engage to take me to Lima, as they say they may touch at Lima or
 they may not. Unless I give them an immense sum they will not engage
 to drop me there. To be brought back to England after a two years'
 voyage without seeing Lima would be a very foolish trip. To make a
 certainty I shall take the first ship for Buenos Ayres, preparations
 for which I have already made."

This unfinished rough draft was intended for one of the men who had
gone to Lima, less fruitful in emergency than Trevithick, who, without
a moment's hesitation, would have constructed a fire-place outside the
boiler, when the internal tube fire-place was found to be too small for
a wood fire. Trevithick's proposing sixty years ago to make his way
over the almost unknown track from Buenos Ayres, on the Atlantic, to
Lima, on the Pacific, was perhaps characteristic of his daring spirit,
that turned all things to good account; but he dreamed not that his
grandson and namesake would at this time be conducting the steam-horse
on the same line of march on the Central Argentine Railway from
Rosario to Cordoba, in the Argentine Republic.

 [Rough draft.]

 "GENTLEMEN,

 "CAMBORNE, _August 19th, 1813_.

 "I received yours at Bridgenorth of the 19th July, ordering a
 steam-engine for rolling sugar-cane. I immediately set the founders to
 work on one for you, which is to be ready by my return to Bridgenorth
 about the end of September. I intend to ship it for Bristol, and will
 call on you on my journey down to Cornwall, as I intend to set it to
 work at Bristol for your inspection before it is put on board ship.
 The price I cannot accurately say at present, as the engine now making
 is on a new principle; and as it will be more simple in construction,
 I hope to be able to render it within the price before stated to you.
 As it is on a new plan I cannot fix the price until I know the cost of
 making. All I can say at present is that it shall not exceed what I
 stated to you in my former letter.

  "I remain, Sirs,
  "Your humble servant,
  "RD. TREVITHICK.

  "MESSRS. PINNEYS AND AMES, _Bristol_."

The engine for the sugar plantations in Jamaica, on an improved plan,
was to be constructed in the short space of six weeks, and if a saving
in cost was effected, the inventor would hand the whole of it to the
purchaser.

 [Rough draft.]

 "SIR,

 "PENZANCE, CORNWALL, _March 8th, 1816_.

 "I received your favour of the 25th January, but did not answer it in
 due course, because I was then erecting a very large engine, which is
 the first on a new plan. This engine, which has been at work about
 a month, performs exceedingly well. The cost of erection and the
 consumption of coal are not above one-third of a Boulton and Watt's,
 to perform the same work. An engine of 4-horse power will not require
 a space of more than 5 feet high, 5 feet long, and 3 feet 6 inches
 wide. In some instances I employ a balanced wheel 5 feet in diameter.
 The water required will be a pint and a half per minute. The coal,
 one quarter of a bushel or 21 lbs. per hour. The price of a machine,
 finished and set to work, 100 guineas. It does not require either wood
 or mason work, but stands independent of every fixture, and may be set
 to work in half an hour after being brought on your premises.

  "Your obedient servant,
  "RICHD. TREVITHICK.

  "DR. MOORE, M.D., _Exeter_."

A 4-horse-power portable high-pressure steam-puffer engine cost
105_l._, with internal fire-tube and machinery attached to the boiler,
ready for work in half an hour after lighting the fire, consumed 21
lbs. of coal and 11 gallons of water for each hour's work, at a cost of
threepence.

The reader's attention has been very imperfectly drawn to the numerous
subjects touched on in these remnants of Trevithick's correspondence
between the years 1804 and 1816; among them may be traced the portable
high-pressure steam-engine, the tubular cylindrical boiler of wrought
iron, the economy of expansive working with steam of 100 lbs. on the
inch, but limiting it to 20 lbs. when not in the charge of experienced
workmen, and testing boilers by water pressure to four times the
intended working pressure.

The economy of heat in smelting furnaces and in the aërated
steam-engine were bold means to large results. The cheap 100l.
steam-engine of 1812, with open-top cylinder and rigid simplicity
of gear, resembling Newcomen's first atmospheric engine, was really
a high-pressure steam expansive engine, with the germ of surface
condensation, as ready to convey itself from mine to mine or from farm
to farm, and to join in performing labourer's work, even to boring and
conveying rock by land or sea, as the most perfect of modern engines;
and yet this unadorned engine, as seen in the agricultural engine
of the following chapter, followed the excellent mechanism of the
double-acting Kensington model of 1798, and the still more beautiful
engine of the 1802 patent and London locomotive.




CHAPTER XVIII.

AGRICULTURAL ENGINES.


The late Mrs. Trevithick said "that during the difficulties in London
in 1808 and 1810, when Trevithick was overwhelming himself with new
experiments and the cost of patents, and law expenses, lawyers and
bailiffs took everything worth having from her house, including
account-books, drawings, papers, and models, which she never saw again."

His earlier account-books left in safety in his Cornish home, though
very disconnected, give trustworthy traces of his work up to 1803. From
that time only detached accounts or papers are found until 1812, when
the unused pages in two old mine account-books of his father served
as his letter (rough-draft) books; and judging from their number and
style, his correspondence was most extensive and varied.

 [Rough draft.]

 "HAYLE FOUNDRY,

 _February 13th, 1812_.

 "TO SIR CHRISTOPHER HAWKINS, Baronet.

 "Sir,--I now send you, agreeable to your request, a plan and
 description of my patent steam-engine, which I lately erected on
 your farm for working a thrashing mill. The steam-engine is equal in
 power to four horses, having a cylinder of 9 inches in diameter. The
 cylinder, with a moderate heat in the boiler, makes thirty strokes in
 a minute, and as many revolutions of the fly-wheel, to every one of
 which the drum of the thrashing mill (which is 3 feet in diameter)
 is turned twelve times. The boiler evaporates 9 gallons of water
 in an hour, and works six hours without being replenished. The
 engine requires very little attention--a common labouring man easily
 regulates it.

 [Illustration: TREVITHICK'S HIGH-PRESSURE STEAM-PUFFER THRASHING
 ENGINE, 1812.]

 "The expense of your engine of 4-horse power, compared with the
 expense of four horses, is as follows:--

                                                        £  _s._
  Original cost of the steam-engine                     80  0
  Building material and rope                            10  0
                                                       ------
                                                       £90  0
                                                       ------
  Interest on the above 90_l._ at 5 per cent.              4 10
  Wear and tear at 5 per cent.                           4 10
                                                       ------
                                                         9  0
                                                       ------
  Original cost of horse machinery for four horses     £60  0
  Interest on the above at 5 per cent.                   3  0
                                                       ------
  Wear and tear at 15 per cent.                          9  0
                                                       ------
                                                        12  0

 "Two bushels or 164 lbs. of coal will do the work of four horses,
 costing 2_s._ 6_d._

 "Four horses at 5_s._ each, gives 20_s._ Cost of coal, 2_s._ 6_d._ as
 compared with 20_s._ for horses.

  "I remain, Sir,
  "Your obedient servant,
  "RICHARD TREVITHICK."


 "CORNWALL,

 _February 20th, 1812_.

 "Having been requested to witness and report on the effect of steam
 applied to work a mill for thrashing corn at Trewithen, we hereby
 certify that a fire was lighted under the boiler of the engine five
 minutes after eight o'clock, and at twenty-five minutes after nine
 the thrashing mill began to work, in which time 1 bushel of coal was
 consumed. That from the time the mill began to work to two minutes
 after two o'clock, being four hours and three-quarters, 1500 sheaves
 of barley were thrashed clean, and 1 bushel of coal more was consumed.
 We think there was sufficient steam remaining in the boiler to have
 thrashed from 50 to 100 sheaves more barley, and the water in the
 boiler was by no means exhausted. We had the satisfaction to observe
 that a common labourer regulated the thrashing mill, and in a moment
 of time made it go faster, slower, or entirely to cease working. We
 approve of the steadiness and the velocity with which the machine
 worked; and in every respect we prefer the power of steam, as here
 applied, to that of horses.

  (Signed)  "MATTHEW ROBERTS, Lamellyn.
            "THOMAS NANKIVILL, Golden.
            "MATTHEW DOBLE, Barthlever."

This first high-pressure steam thrashing machine was working on the
13th February, 1812, at Trewithen, the property of Sir Christopher
Hawkins, as proved by Trevithick's drawing of the machine, his account
of the work performed, and the report of the three wise men that the
power of steam was preferable to the power of horses. Its first cost
was less than that of a horse machine; but to make the calculated
amounts come right Trevithick charged 15 per cent. for wear and tear
on the horse machinery, and but 5 per cent. on the steam-engine;
overlooking the cost of the horses, which would have made the outlay
for the horses and machinery greater than for the steam-engine.

The whole design evidences simplicity and consequent cheapness; no
complication of valves or valve-gear, no cylinder cover, parallel
motion, guide-rods, or air-pump, with its condenser and injection-water.

The 4-horse engine, with boiler complete, cost 90_l._ A common labourer
worked it, and as it needed no supply of feed-water during six hours
of work, the cost and attention of supplying feed were avoided. If a
supply was required during the day it could be given by a pipe with two
taps.

This first use of steam in agriculture was immediately followed by
Lord Dedunstanville of Tehidy, Mr. Kendal of Padstow, and Mr. Jasper
of Bridgenorth. Sir Charles' request for a more official report signed
by disinterested persons brought a reply that the thrashing engine
continued to work well. "It far exceeds my expectation. I am now
building a portable steam-whim, on the same plan, to go itself from
shaft to shaft." "If you should fall in with any West India planter
that stands in want of an engine, he may see this at work in a month,
which will prove to him the advantage of a portable engine to travel
from one plantation to another. The price complete is 105_l._"[10]

[Footnote 10: See Trevithick's letter, 10th March, 1812, chap, xx.]


 "DEAR SIR,

 "ARGYLE STREET, _19th March, 1812_.

 "I am sorry it is not convenient for me to advance you the money for
 Wheal Liberty; adventurers having the dues very low, ought to furnish
 the needful. I am very glad you have succeeded with your portable
 steam-engine, and am persuaded they will be more and more adopted.
 I have shown your account of your thrashing by steam, and Sir John
 Sinclair and Mr. ---- very highly approve it. Sir John Sinclair wished
 the communication had been made to the Board of Agriculture. Sir John
 wished me to transmit you the enclosed on coals moved by steam ...
 whether you had a plan of this sort, as they would be very serviceable
 in passing the friths in Scotland. He seems to think you ought to
 advertise your steam-engines for thrashing; indeed, I think so too.

 "By the enclosed letter, Sir John Sinclair wishes you to send him an
 account of your improved steam-engines. You will be careful in drawing
 up your letter to Sir John, because it will probably be read to the
 Board of Agriculture, and perhaps inserted in their publication. You
 will begin by acknowledging his letter, of date ... respecting the
 American passage boat ... and your improved small steam-engine. You
 will give him an account of the saving you have effected at Dolcoath,
 and a certificate of the same by the mining captains; the engine for
 thrashing you built for me, and the work it did, and the coals it
 consumed; the expense of the steam-engines, and the uses they may be
 applied to.

  "I remain, dear Sir,
  "Yours most obediently,
  "C. HAWKINS."

In 1812 Trevithick advertised the use and sale of steam-engines,
weighing 15 cwt., costing 63_l._, for thrashing, grinding, sawing, or
other home work; and also a more powerful engine for the steam-plough,
or the harrow and spade machine for 105_l._, to travel from farm to
farm. He wrote to Sir John Sinclair:[11]--

 "I received from Sir Charles Hawkins a copy of Dr. Logan's letter to
 you, also a note from you to Sir Charles Hawkins, both respecting
 the driving boats by steam; respecting the engine for thrashing,
 chaff-cutting, sawing, &c. I am now making one of about two-thirds
 the size of Sir Charles Hawkins', which will be portable on wheels.
 By placing the engine in the farm-yard, and passing the rope from the
 fly-wheel through the barn-door, or window, and around the drum on the
 machine axle, it may be driven.

 [Footnote 11: See Trevithick's letter, 26th March, 1812, chap. xv.]

 "The steam may be raised, and the engine moved a distance of two
 miles, and the thrashing machine at work, within one hour.

 "The weight, including engine, carriage, and wheels, will not exceed
 15 cwt.; about the weight of an empty one-horse cart.

 "The size is 3 feet diameter, and 6 feet high. If you wish to have one
 of this size sent to the Board of Agriculture as a specimen, the price
 delivered in London will be sixty guineas."

This engine differed from that referred to in the drawing of Sir
Charles Hawkins, mainly in the boiler having the fire-place in the
fire-tube, requiring no brickwork, and having the advantage of
portability. It was very like the earlier locomotive boiler, except
that it was placed upright, as steam-cranes now use boilers, instead of
being horizontal.

 [Rough draft.]

 "CAMBORNE, CORNWALL,

 _April 26th, 1812_.

 "TO SIR JOHN SINCLAIR.

 "I have your favour of the 4th instant, informing me that you had sent
 my letter respecting propelling ships by steam to the Navy Board; and
 also requesting a drawing and statement of the thrashing engine to
 be sent to the President of the Board of Agriculture, which shall be
 forwarded immediately.

 "I beg to trouble you with a few wild ideas of mine, which perhaps may
 some future day benefit the public, but at this time remain buried,
 for want of encouragement to carry it into execution.

 "The average consumption of coals in large steam-engines is about 84
 lbs. (or one bushel), to lift 10,000 tons of water or earth 1 foot
 high.

 "The average cost of this coal in the kingdom is sixpence. The average
 of a horse's labour for one day is about 4000 tons lifted 1 foot high,
 costing about 5_s._

 "A man's labour for one day is about 500 tons lifted 1 foot high,
 costing 3_s._ 6_d._

 "I have had repeated trials of the water lifted by coals, horses,
 and men, proving that where a bushel of coal can be purchased for
 sixpence, that sixpence is equal to 20_s._ of horse labour, and to
 3_l._ 10_s._ of men's labour.

 "If you calculate a man to lift 500 tons 1 foot high, it is equal to
 100 tons lifted 5 feet high; a very hard task for a man to perform in
 a day's work.

 "This calculation proves the great advantage of elemental power over
 animal power, which latter I believe can in a great part be dispensed
 with if properly attended to, especially as we have an inexhaustible
 quantity of coals.

 "To prove to you that my ideas are not _mere_ ideas, in general my
 wild ideas lead to theory, and theory leads to practice, and then
 follows the result, which sometimes proves of essential service to the
 public.

 "About six years ago I turned my thoughts to this subject, and made a
 travelling steam-engine at my own expense to try the experiment.

 "I chained four waggons to the engine, each loaded with 2-1/2
 tons of iron, besides seventy men riding on the waggons, making
 altogether about 25 tons, and drew it on the road from Merthyr to the
 Quaker's-yard (in South Wales), a distance of 9-3/4 miles, at the rate
 of four miles per hour, without the assistance of either man or beast,
 and then, without the load, drove the engine on the road sixteen miles
 per hour.

 "I thought this experiment would show to the public quite enough to
 recommend its general use; but though promising to be of so much
 consequence, has so far remained buried, which discourages me from
 again trying, at my own expense, for the public, especially when my
 family call for the whole of my receipts from my mining concerns for
 their maintenance.

 "It is my opinion that every part of agriculture might be performed
 by steam; carrying manure for the land, ploughing, harrowing, sowing,
 reaping, thrashing, and grinding; and all by the same machine, however
 large the estate.

 "Even extensive commons might be tilled and effectually managed by a
 very few labourers, without the use of cattle.

 "Two men would be sufficient to manage an engine, capable of
 performing the work of 100 horses every twenty-four hours; requiring
 no extensive buildings or preparations for labourers or cattle, and
 having such immense power in one machine as could perform every part
 in its proper season, without trusting to labourers.

 "I think a machine that would be equal to the power of 100 horses
 would cost about 500_l._

 "My labour in invention I would readily give to the public, if by a
 subscription such a machine could be accomplished and be made useful.

 "It would double the population of this kingdom, for a great part of
 man's food now goes to horses, which would then be dispensed with, and
 so prevent importation of corn, and at a trifling expense make our
 markets the cheapest in the whole world; because there are scarcely
 any coals to be found except in England, where the extreme price, duty
 included, does not exceed 2_s._ per bushel.

 "I beg your pardon for having troubled you with such a wild idea, and
 so distant from being carried into execution; but having already made
 the experiment before stated, which was carried out in the presence
 of above 10,000 spectators, who will vouch for the facts, I venture
 to write to you on the subject, for the first and only self-moving
 machine that ever was made to travel on a road, with 25 tons, at four
 miles per hour, and completely manageable by only one man, I think
 ought not to be dropped without further experiments, as the main point
 is already obtained, which is the power and its management.

  "Your most obedient servant,
  "RICHARD TREVITHICK."

The Board of Agriculture in 1812 had their attention drawn to the
feasibility of using the steam-engine to save agricultural labour and
lessen the cost of working land. Trevithick's intuitive knowledge told
him his application would be in vain, though an engine was at work
proving the saving of horse-power in the item of thrashing corn.

"I beg to trouble you with a few wild ideas of mine, which _perhaps may
some future day benefit the public_."

A steam-engine could exert as much power by the consumption of 6_d._
worth of coal as could be given by 20_s._ of horse-power, or by 70_s._
worth of men's power.

"Ideas lead to theory, theory leads to practice, then follows the
result, which sometimes proves of essential service to the public."

"It is my opinion that every part of agriculture might be performed
by steam. Carrying manure for the land, ploughing, harrowing, sowing,
reaping, thrashing, and grinding; and all by the same machine, however
large the estate."

"Two men would manage an engine capable of performing the work of 100
horses."

Such a use of the steam-engine, judiciously managed, "would double the
population of this kingdom, and make our markets the cheapest in the
world; because England is the country best supplied with coal and iron
for steam-engines, and the land now growing food for horses would be
available for man."

Its cost would be 500_l._, and its power sufficient to propel
the largest subsoil ploughs and tormentors; and had the Board of
Agriculture supplied such a sum of money as is now ordinarily given
by a farmer for a steam-plough, we should have had in 1812 ploughing,
harrowing, sowing, reaping, &c., by steam. Years before, the same kind
of engine had been made to work pumps, wind coal from shafts, drive
rolling mills, tilt hammers, and steamboats, and convey material from
place to place; and why should not his promise to the farmer be also
made good with his increased knowledge derived from eight years of
active experience? Receiving small encouragement in England, he applied
to sugar-cane planters to give his engines a trial in the West Indies.

 [Rough draft.]

 "SIR CHARLES HAWKINS, Bart.,

 "CAMBORNE, _1st May, 1812_.

 "Sir,--I have your favour of the 27th April, respecting a steam-engine
 for your friend for the West Indies, of the power of ten mules
 employed at one time. This power we calculate equal to forty mules
 every twenty-four hours, as six hours' hard labour is sufficient for
 one mule for one day.

 "The expense of an engine of this power complete delivered in London
 would be 200_l._ The consumption of coals about 84 lbs., or one
 bushel, to equal the labour of three mules, or from 13 to 14 bushels
 of coal every twenty-four hours to perform the full work of forty
 mules (or in proportion for a lesser number), with a waste of about 15
 gallons of water per hour, unless a reservoir was made to receive the
 steam, and then to work the same water over again.

 "Where water is scarce, nearly the whole may be saved.

 "You remarked that the rope might slip round the notch in the wheel;
 but to prevent any risk of that kind, I apply a small chain instead of
 the rope, which works the same as a chain on the barrel of a common
 thirty-hour clock.

 "The speed of the periphery of the fly-wheel is about eight miles per
 hour, which I think is nearly double the speed of the mules when at
 work in the mill. This would reduce the size of the part which carries
 the chain on the cattle mill to half the diameter of the present walk
 of the cattle, which might be done without altering or interfering
 with the present cattle mills, and might, if required, either work
 separately or in conjunction with the mules in the same mill at the
 same time.

 "To inform your friend of the power and effect of such an engine, I
 prefer his sending some person down to Cornwall, to see it tried on
 some of the cattle mills or whims in the mines.

 "Engines that have been sent to the West Indies hitherto have cost
 nearer 2000_l._; very large, heavy, and complicated machines,
 requiring 2500 gallons of water per hour for condensing, and could
 only be managed by a professed engineer, while any common labourer can
 keep in order and work these engines. If you prefer to send a person
 with it, the cost will be about 40_s._ per week.

  "I remain, Sir,
  "Your most obedient servant,
  "RICHARD TREVITHICK."

This letter indirectly points out two long-standing radical errors in
engineering phraseology. An early method of describing the value of
an engine was by stating the number of pounds it would lift one foot
high by the burning a bushel of coal, called the duty of an engine.
Trevithick's bushel was 84 lbs., while other engineers, under the same
term of bushel, meant various weights, up to 120 lbs.

Another form of speaking was the horse-power of an engine; meaning
that a horse could lift a certain number of pounds one foot high in
a minute, and that a steam-engine lifting ten times as much was a
10-horse engine; but, as Trevithick points out, a horse only works at
that rate for six hours out of twenty-four, while the steam-engine
works continuously, performing the work of forty horses, yet is called
a 10-horse engine.

The high-pressure engine suitable for the West Indies was to be adapted
to the existing horse or mule machinery, that either power might be
used. Its first cost and expense in working to be much less than that
of the Watt low-pressure steam vacuum engine.

 [Rough draft.]

 "SIR CHARLES HAWKINS, Bart.,

 "CAMBORNE, _June 13th, 1812_.

 "Sir,--Yours of the 15th of last month I received, enclosing a drawing
 of a sugar-mill from Mr. Trecothick, which I should have answered per
 return, but was at that time in treaty for an engine for a sugar-mill
 with a Mr. Pickwood, who is in St. Kitts in the West Indies.

 "The engine is now being erected at Hayle Foundry, of the power
 of twelve mules at a time, or equal to forty-eight mules during
 twenty-four hours.

 "The cost is 210_l._ complete, with numerous duplicate parts.

 "I hope she will be finished and sent off in a short time.

 "I have now so fully proved the use of those engines, that I have
 engaged to take this one back if it does not answer their purpose, and
 to refund the whole sum if they return the engine to me in working
 order within four years.

 "This gentleman says, if this engine answers he shall have two more
 for his own use, and four of his friends are waiting to see the result
 before ordering their engines.

 "The mules that will be turned out of use by Mr. Pickwood's engine
 will sell for five times the sum the engine will cost him, exclusive
 of the wear of mules, with their keep and drivers, besides the greater
 dispatch and pleasantness of working a machine instead of forcing
 animals in so hot a climate.

 "If your friend wishes an engine of this power and on the same terms,
 I can get two made and sent to London nearly in the same time as one.
 Enclosed I send to you a rough sketch of the engine and mill. I am of
 your opinion, that Sir John Sinclair has taken a useless journey by
 calling on the Navy Board, for nothing experimental will ever be tried
 or carried into effect except by individuals.

 "If I could get an Act of Parliament for twenty-one years for only
 one-tenth part of the saving which I could gain over animal power and
 expense, I have no doubt but that I could get money to carry the plan
 fully into effect for propelling ships, for travelling with weights on
 roads, and doing almost every kind of agricultural labour.

 "But a patent is but for fourteen years, and open to constant
 infringement; for the inventor of general and useful machinery is
 a target for every mechanic to shoot at, and unless protected or
 encouraged by some better plan than a common patent, will have the
 whole kingdom to contend with in law, and most likely receive ruin for
 his reward, which has too often been the case.

 "A plan of such magnitude as this promises to be of, I think ought to
 be carried into effect by subscription, and as soon as accomplished,
 the subscribers to be repaid, and the invention thrown open for the
 use of the kingdom at large. I think about 1000_l._ or 1500_l._ would
 test the designs.

 "It is expected that Mr. Praed will spend some time in this
 neighbourhood; I hope I shall be able to prove to you and to him the
 great use of propelling barges by steam. I have a small engine now
 at foundry, and would put it on board one of their barges for your
 inspection. I am very much obliged for your continued favours, and beg
 pardon for so often troubling you. I have so fully proved the great
 advantages resulting from those portable engines, that I very much
 wish the public to have the full use of them.

  "I remain, Sir,
  "Your most humble servant,
  "RICHARD TREVITHICK."

A 12-mule-power engine for St. Kitts was being erected at Harvey's
foundry at Hayle; Trevithick making himself liable for the whole cost,
in case it should not answer the purpose. The mules thrown out of work
by the engine would sell for five times as much as the engine cost, to
say nothing of the saving in wear and tear of drivers and mules, and
the unpleasantness of driving a mule in hot weather as compared with a
machine.

If an Act of Parliament would give him one-tenth of the saving he
could effect during twenty-one years, a company might be formed for
carrying into full effect his plans for propelling ships, travelling
with weights on roads, and performing almost every kind of agricultural
labour, while a patent for fourteen years was open to constant
infringement, and the inventor of useful machinery was a target for
every mechanic to shoot at, had law suits with the kingdom at large,
and ultimate ruin, as a reward for his labours. Inventions of such
general application, when fairly established, should be thrown open
to the public, Government paying the inventors their expenses, and
reasonable reward for their time.

 [Rough draft.]

 "MR. PICKWOOD,

 "CORNWALL, CAMBORNE, _17th June, 1812_.

 "Sir,--Yours of the 17th April I received about twenty days since,
 and from that time to the present have been in treaty with Messrs.
 Plummer, Barham, and Co., for your engine. We have now closed for
 an engine complete, of the power of twelve mules at a time, with
 suitable duplicates, chains, &c., for 210_l._ I very much wish for
 your engine to be set to work by your own workmen, to show the
 planters the simplicity and easy management of the machine, and also
 save the expense of an engineer, which will tend to promote their
 use. The engine will be set to work before it is sent off, and every
 possible care taken to execute it in the most perfect order. From the
 experience I have had with common labourers keeping these engines
 in order, since I wrote to you, I have no doubt you will get on
 satisfactorily.

 "I hope to get the engine ready in five or six weeks, but I fear there
 will be loss of time in shipping it. You may rest assured that I will
 spare no time or attention to promote the performance of this engine.
 I am so far satisfied with the probability of its fully answering your
 purpose that I voluntarily offered Messrs. Plummer, Barham, and Co.,
 that if you return it to me for working repairs within four years, I
 will refund the whole of the sum I am to receive for it. I will take
 particular care to mark every part and send you a full description.

 "Enclosed I send you a sketch of the engine attached to a sugar-mill.
 Please write to me by return of the packet; it may be in time, before
 the engine is shipped, to alter, or send you such things as I may not
 be acquainted with. I shall be glad to know the number of yards your
 mules travel in an hour when going at what you call a fair speed, in
 the mill, and also what number of rounds you wish the centre roll to
 make in an hour when worked by the engine.

  "I remain, Sir,
  "Your very humble servant,
  "RD. TREVITHICK.

  "R. W. PICKWOOD, Esq.,
  "_St. Kitts, West Indies_."

These are not the remarks of an uncertain schemer; every sentence
having the impress of the ability and fixed intention of perfecting the
work, and the belief that the simplicity of the engine would enable a
common labourer to use it.

 [Rough draft.]

 "SIR CH. HAWKINS, Bart.,

 "CAMBORNE, _5th July, 1812_.

 "Sir,--If your friend Mr. Trecothick intends to have a sugar-mill
 engine immediately finished and sent out with the one I am now making
 for Mr. Pickwood, he ought not to lose any time in giving his orders.
 I have made inquiry at Falmouth about sending out Mr. Pickwood's
 engine for St. Kitts on board a packet, which would save much time,
 but I fear it cannot be granted unless application is made by some
 person of note to the Post Office in London. Mr. Banfield of Falmouth
 told me that if application was made to send out a model as a trial,
 he had no doubt but it would be granted.

 "This experiment with the portable engine that will travel from one
 plantation to another and work without condensing water, is certainly
 of the greatest consequence to the planters, and as the whole weight
 will not exceed 1-3/4 ton, I should hope that the Commissioners at
 the Post Office will grant this request. I am sorry to trouble you
 so often about my business, but I beg the favour of your goodness to
 inform me through what channel I ought to make this application.

  "I remain, Sir,
  "Your most obedient humble servant,
  "RD. TREVITHICK."

This experiment with the 1-3/4 ton portable engine to travel from one
plantation to another, needing no condensing water, was certainly of
the greatest consequence to the planters in the West Indies, and should
have been of equal importance to the people in England.

Judging from the weight and cost, as compared with agricultural
engines of the present day, Trevithick was nearer the mark then than
we are now; its working without condensing water the engineers of that
day believed to be impracticable, a fundamental error which greatly
retarded the use of the high-pressure steam-engine. The providing
sufficient condensing water was often a most serious item of cost, and
as water mains were not in use, a deep well was a necessary part of a
steam vacuum engine.

 [Rough draft.]

  "GENTLEMEN,      "CORNWALL, CAMBORNE, _October 16th, 1812_.

 "Yours of the 30th of September I found at my house on my return
 yesterday from a journey. I am sorry to inform you that Mr. Pickwood's
 engine is not ready. Near three months ago I set my smiths and
 boiler-makers to work to complete an engine for Mr. Pickwood, which
 parts were finished five or six weeks ago. The other parts of the
 engine, which were to have been made of cast iron, were ordered and
 commenced at a foundry in this county, belonging to Blewett, Harvey,
 and Vivian, and would have been finished and the engine shipped long
 since had not these partners in the iron foundry quarrelled with
 each other, and the Lord Chancellor has laid an injunction and set
 idle their foundry. I have since ordered the castings to be made at
 a foundry at Bridgenorth, in Shropshire, belonging to Hazeldine,
 Rastrick, and Co., who will complete the engine and send it to you in
 about two months, at which time I intend to be in town to set it to
 work before it is shipped for the West Indies.

  "I remain, Gentlemen,
  "Your very humble servant,
  "RICHD. TREVITHICK.

  "MESSRS. PLUMMER, BARHAM, AND CO.,
  "_London_.

 "P.S.--Immediately on my receiving your order to prepare an engine for
 Mr. Pickwood I wrote to inform him that I had begun it, and enclosed
 a drawing of the engine with the method of connecting the engine to
 the cattle-mills, and requested he would remit to me his remarks on
 it, which I received by the last packet, from which it appears for
 the best that the engine is not in a forward state, because the parts
 would not have been so suitable to the purpose as they will now be."

Fortune was against Trevithick. A difficulty between his brother-in-law
Harvey, and his old partner Vivian, with Blewett, retarded the
completion of the engine; and the castings so anxiously waited for were
ordered from Hazeldine and Rastrick. The wrought-iron work was made by
the old smiths in his neighbourhood, who had long been in the habit of
hammering his schemes into shape. This patchwork way of constructing
engines made success much more difficult.

Trevithick often laughed heartily at the following incident which
occurred during this quarrel at Harvey's works:--Blewett sent a
handsome silver teapot to Miss Betsy Harvey, who kept her brother's
house, called Foundry House. Trevithick was sitting with them when
the box was brought in and opened. Mr. Henry Harvey was indignant at
Mr. Blewett sending a bribe or make-peace to his sister, and threw
the silver teapot under the fire-place. Trevithick, however, quietly
picked it up, pointed out the dinge it had received, wrapped his pocket
handkerchief around it, and saying, if it causes bad feeling here it
will do for Jane, marched away home with the pot. The writer drank tea
from it recently, and also laughed at the dinge.

The following was written to Mr. Rastrick in December, 1812:[12]--

 "I have been waiting your answer to my last, and especially that part
 respecting the West India engine, as there is a large field there for
 engines of this kind. I have received an order for a thrashing engine
 for Lord de Dunstanville of Tehidy, and as I wish those thrashing
 engines to be known through the country, I intend to take one of
 the engines ordered for Padstow and send it to Tehidy; one of the
 Padstow farmers can wait until you make another for him; therefore I
 would thank you to send the first finished by ship from Bristol for
 Portreath or Hayle. Send a drum with everything complete, of which
 you are a better judge than I; probably about 3 feet in diameter
 and 3-1/2 feet long will be sufficient. There must be a fly-wheel,
 with a notch to carry the rope, and also a small notch wheel on the
 drum-axle. I think 6-1/2 feet diameter for the fly and 9-1/2 inches
 diameter for the small wheel, will give speed enough to the drum. Mind
 to cast a lump or screw on a balance of about 1 cwt. on one side of
 the wheel. There must be two stands on the boiler, and a crank-axle
 or otherwise a crank-pin in the fly-wheel, whichever you please; with
 a shaft 3 feet long with a carriage. The engine to stand in a room
 under the turn-about, 7-1/2 feet high, 7 feet wide, and 17 feet
 long. The fly-wheel will stand across the narrow way of the room. The
 rope will go up through the floor and the drum be shifted by a screw,
 horizontally on the barn floor, so as to tighten the rope. I shall put
 down the top of the boiler level with the surface, with an arched way
 to the fire and ash-pit underground to prevent the chance of fire,
 which the farmers are very much afraid of.

 [Footnote 12: See rough draft, Trevithick's letter, 7th December, 1812,
 chap. xvii.]

 "I send you a sketch showing how it is to stand. I do not bind you
 to the size of the drum or wheels, only the room that the fly-wheel
 works in is but 7 feet wide. Put the engine and drum for Lord de
 Dunstanville out of hand neat and well, as it will be well paid for,
 and make the stands, &c., in your own way."

This description of Lord Dedunstanville's thrashing machine illustrates
the drawing of that supplied to Sir Charles Hawkins.

 [Rough draft.]

  "MR. RASTRICK,        "CAMBORNE, _January 26th, 1813_.

 "Sir,--I have your favour of the 10th inst., in which you do not
 state the time when you expect I shall have either of the engines
 that you are executing. As so much time has elapsed since the orders
 were given, the persons that ordered them are quite impotent. The
 ploughing engine that I sent you a drawing for, after being tried for
 that purpose, was to have been sent to Exeter for pumping water out
 of the foundations of a new bridge; but as they intend to begin their
 work at the bridge before the end of March, the engine must be there
 before that time, or they will erect horse machines and not use the
 engine. I have therefore been obliged to send the small boiler that
 I had for that purpose to Hayle Foundry, and get the castings made
 there for this engine to get it in time to prevent losing the order.
 I have also been obliged to take the small portable engine from Wheal
 Alfred Mine and have new apparatus fitted to it, to apply this engine
 for Plymouth Breakwater. A small engine, from the same patterns as
 Sir Charles Hawkins' thrashing engine, which I had at work in a mine,
 I have been obliged to send to one of the farmers at Padstow for
 thrashing, instead of one of those engines that I ordered from you. I
 expect that the people who ordered the engine for the West Indies are
 also tired of waiting. I have two other applications for engines for
 the West Indies, and the Messrs. Fox will want a great many engines of
 that size for the Plymouth Breakwater. They are to provide machinery,
 with every other expense, and I am to have a certain proportion of
 what I can save over what it now costs them to do it by manual labour.
 I think I have made a very good bargain, for if the plan succeeds I
 shall get a great deal of money, and if it fails I shall lose nothing.
 They have engaged with the Government to deliver 3,000,000 tons, for
 which they have a very good price, even if it was to be done by men's
 labour. I hope I shall get the engine soon on the spot, and will then
 let you know the result. As the boiler that was intended for the
 ploughing engine is to be sent to Exeter, I wish you to finish that
 engine with boiler, wheels, and everything complete for ploughing and
 thrashing, as shown in the drawing, unless you can improve on it.
 There is no doubt about the wheels turning around as you suppose,
 for when that engine in Wales travelled on the tramroad, which was
 very smooth, yet all the power of the engine could not slip around
 the wheels when the engine was chained to a post for that particular
 experiment.

 "That new engine you saw near the seaside with me is now lifting forty
 millions 1 foot high with 1 bushel of coal, which is very nearly
 double the duty that is done by any other engine in the county. A few
 days since I altered a 64-inch cylinder engine at Wheal Alfred to the
 same plan, and I think she will do equally as much duty. I have a
 notice to attend a mine meeting to erect a new engine equal in power
 to a 63-inch cylinder single, which I hope to be able to send to you
 for. I have also an appointment to meet some gentlemen at Swansea, to
 erect two engines for them, one to lift water, the other coal, which
 you will hear more about, I expect, soon. If I can spare a few days
 when at Swansea, I will call to see you at Bridgenorth. I have not
 seen Mr. Richard since you left, but will call on him in a few days
 and do as you request. If you think the fly-wheel is not sufficiently
 heavy for his engine, add half a ton more to the ring.

 "If you cannot finish all these engines at the same time, I would
 rather the smaller ones should be finished first and Mr. Richards'
 stand a little, because if his engine was now ready he would not pull
 down his thrashing machine until he had nearly thrashed all his corn,
 and the machine now stands on the spot where the mill is to be erected.

 "If I call on you from Swansea I think I shall be able to show you a
 new idea, which I think will, if carried into practice, be of immense
 value. Please to write to me and say particularly how you are getting
 on, and when you are likely to finish the engines ordered.

  "R. T."

Trevithick had sent a drawing of a _ploughing_ engine to Rastrick at
Bridgenorth, that the castings might be made, while he himself was
having the boiler and wrought-iron work constructed in Cornwall. The
engine had been ordered as a portable pumping engine, for removing
water from the foundation of a bridge at Exeter; but before sending it
to its destination, he had arranged to plough with it, as a means of
perfecting the plans and drawings for a more suitable ploughing engine
then in construction, to be fitted "with boiler, wheels, and everything
complete for ploughing and thrashing, as shown in the drawing." The
_friction of the wheels on the ground would be greater than the power
of the engine_; therefore they would not slip when the full power was
applied to draw a plough any more than the Welsh engine, the wheels of
which did not slip though resting on smooth iron.

One of his small engines, which had been at work in a mine, was sent
as a thrashing engine to Padstow. It is evident that, having given
a portion of his attention for a year or two to the question of
steam agriculture, he had so far progressed in 1813 as to construct
thrashing machines, portable agricultural engines, and steam-ploughs to
be moved by wheels as in locomotives; reaping, sowing, and other work,
was also in future to be the work of the steam-engine.

A drawing by Trevithick--having as usual neither name, date, nor
scale, nor writing of any kind, but the watermark in the paper is
1813--illustrates his ideas expressed to Sir Charles Sinclair in
1812:--"It is my opinion that every part of agriculture might be
performed by steam." The thrashing and grinding engines were at work,
and the tormenting harrowing engine was probably designed for bringing
under steam cultivation the extensive commons referred to. In those
days, before the practice of underground drainage, the surface of
cultivated land was thrown into furrows, or a series of small hills
and vales, the latter acting as the surface drain for carrying off the
water.

Suppose the first step in cultivating a common to be the breaking of
the soil, and throwing it into uniform lines of rise and fall that
facilitated drainage without inconveniencing the tillage, what better
machine could have been devised than Trevithick's? A combination of the
modern tormentor and harrow loosened the ground to the required depth,
which was then, by a revolving wheel with spades, thrown on one side,
resulting in uniform lines of ridges and hollows. The steam-shoveller
was removed, or the tormentor irons raised, when only the harrow was
required.

The absence of the ordinary shafts at the front end of the framing
indicates that the spade-tormentor was not to be drawn by horses, but
whether by a locomotive or by a fixed engine is not self-evident.

[Illustration: TREVITHICK'S STEAM SPADE-TORMENTOR, 1813.]

 [Rough draft.]

  "MR. KENDAL,         "CAMBORNE, _January 26th, 1813._

 "Sir,--I have yours of the 17th inst. The thrashing machine engine is
 ready for you, and shall be sent up immediately. I wish you to get
 about 100 fire bricks, 200 common bricks, 20 loads of stone, and 20
 bushels of lime. The house will get finished while I am fixing the
 engine. About 1500 or 1600 weight of iron for your engine has been
 sent to the Blue Hills Mine, St. Agness. I wish you could send down
 your cart to fetch it from there to Padstow. There is no part of
 these castings but may be easily conveyed in a common butt or cart.
 When you have the stone, brick, and lime ready, and a cart to send to
 St. Agness for the castings, please to write me, and I will come to
 Padstow at the same time with them, and finish the engine. The sooner
 you get ready the better, as I expect to have an engagement in about
 four weeks' time, that would prevent my coming to Padstow for some
 time; therefore I wish to get your engine finished before that time.
 Please to write me as early as possible, and let me know when you will
 be ready for me, and what day I shall meet your cart at St. Agness for
 the castings.

  "Your obedient servant,
  "RICHARD TREVITHICK."

Real inventors hesitate not to erect their own engines, lend a hand
in building the house, walk to the scene of action, or take a lift in
a cart; and by such steps was the gift of genius moulded to the wants
of daily life; while the modern engineer of eminence, living in large
cities, knows little of the minutiæ of his work, or even of the working
mechanics on whose skill the success of his ideas is dependent.

 "In 1815, Mr. Kendal, the proctor of Padstow, sent for me to repair
 his steam-engine. To prevent the old disputes in collecting his corn
 tithes, he had at work one of Captain Trevithick's steam thrashing
 machines. The small farmers sent their corn produce to him to be
 thrashed; the grain was measured, the tenth taken out, the remainder
 returned to the farmer. The three-way cock, which worked the engine,
 was joined in its shell; on freeing it the engine continued to work
 very well."[13]

 [Footnote 13: Captain Samuel Grote's recollections, 1858.]

 "In 1818 I put a new four-way cock to a thrashing engine that Captain
 Trevithick had made for Mr. Kendal, of Padstow, who was the receiver
 of tithe corn. The boiler was a tube of wrought iron, about 4 feet in
 diameter and 6 feet long, standing on its end. The cylinder was fixed
 in the top of the boiler; an upright from the top of the cylinder
 supported the fly-wheel shaft; a connecting rod from the crank-pin in
 the fly-wheel was fastened to a joint-pin in the piston. The cylinder
 had no cover. The four-way cock was worked by an excentric on the
 shaft, moving a lever, which was kept in contact with the excentric by
 a spring."[14]

 [Footnote 14: Recollections of Captain H. A. Artha, Penzance, 1868.]

 "About 1824 I worked in Binner Downs Mine one of Captain Trevithick's
 puffer whim-engines. The boiler was cylindrical, made of wrought iron.
 It stood on its end, with the fire under it, and brick flues around
 it. The cylinder was let down into the top of the boiler. A four-way
 cock near the top of the cylinder turned the steam on and off. The
 fly-wheel and its shaft were fixed just over the cylinder. A lever and
 rod worked the four-way cock and feed-pole. The waste steam puffed
 through a launder into the feed-cistern. The cylinder was about 12
 inches in diameter, with a 3-feet stroke."[15]

[Footnote 15: Recollections of Henry Vivian, Harvey and Co.'s Works,
1869.]

Mr. Kendal's steam thrashing machine remained at work at least six
years, during which time the only apparent repair was the four-way
cock, worked by an excentric, which, if neglected, was apt to stick
fast in its shell.

One of the puffer-whims erected about this time was similar to the
thrashing engine for Padstow, differing from the earlier one made
for Sir C. Hawkins, in having a portable boiler so arranged that if
necessary it could be easily placed on wheels.

 [Rough draft.]

  "SIR,        "CAMBORNE, _March 15th, 1813_.

 "I have your favour of the 11th inst. respecting a steam-engine for
 thrashing. I have made several, all of which answer the purpose
 exceedingly well. They are made on a very simple construction so as
 to be free from repairs, and are kept in order and worked by the farm
 labourers, who never before saw a steam-engine. The first I made on
 this plan was for Sir Christopher Hawkins, who resides at this time
 in Argyll Street, Oxford Street, London. If you call on him, he, I
 doubt not, would give you every information you require respecting its
 performance. This was a fixed engine, because it was only required to
 work on one farm. It has been at work nearly eighteen months, and has
 not cost anything in repairs, nor any assistance but from the labourer
 who puts in the corn; he only gives three or four minutes every hour
 to put on a little coal. A few pails of water, put into the furnace in
 the morning, is sufficient for a day's work. They have at different
 times tried what duty the engine would perform with a given quantity
 of coal, and found that two Cornish bushels, weighing 168 lbs., would
 get up steam and thrash 1500 sheaves of wheat in about six hours.

 "Before this engine was erected, they usually thrashed 500 sheaves,
 with three heavy cart-horses for a day's work. I cannot say exactly
 the measurement of the corn that it thrashed, but it was considerably
 above 60 winchesters of wheat with 168 lbs. of coal; not a halfpenny
 in coal for each winchester of wheat.

 "The engines that I have since erected have performed the same duty.

 "The horse machinery is thrown out of use, but the same drum is turned
 by the engine.

 "A fixed engine of this power I would deliver to you in London for 100
 guineas; it would cost you about 15_l._ more to fix the furnace in
 brickwork.

 "A portable engine costs 160 guineas, but it would cost nothing in
 erecting, as it will be sent with chimney and every thing complete on
 its own wheels (the drum, &c., excepted), which you may convey with
 one horse from farm to farm as easy as a common cart.

 "If you have not sufficient work for it you can lend it to your
 neighbours. The last engine I erected was about three weeks since, for
 a farmer that kept four horses and two drivers. The parts of the horse
 machine thrown out of use, together with the four horses, sold for
 more money than he gave me for the engine, exclusive of 4_l._ per week
 that it cost him in horse keep and drivers to thrash 3000 sheaves per
 week.

 "Now the engine performs more than double that work, and does not cost
 above 10_s._ per week; and the labourer in the barn does double the
 work he did before for the same money. If you wish the same engine to
 have sufficient power to turn one pair of mill-stones, the cost will
 be 220 guineas.

  "R. TREVITHICK.

  "MR. J. RAWLINGS, _Strood, Kent_."

  "CAMBORNE, _28th August, 1813._

 "MESSRS. HAZELDINE, RASTRICK, AND CO.,

 "Gentlemen,--Lord Dedunstanville's engine thrashed yesterday 1500
 sheaves in 90 minutes with 40 lbs. of coal.

  "RD. TREVITHICK."

The first steam thrashing engine was worked by a labouring man for
eighteen months, without needing repair, or even attention beyond three
or four minutes each hour to put on a little coal.

Necessary stoppages for various purposes caused a day's work to be
no more than the engine could perform in half a day. No additional
feed-water was required during an ordinary day's work to thrash 1500
sheaves of wheat with 168 lbs. of coal, while on a special occasion
that quantity was thrashed in an hour and a half, consuming only 40
lbs. of coal. Three horses during three days were required to do the
same amount of work. A farmer sold his horses used in thrashing for
more money than his engine cost, which did twice as much work at a
reduced expenditure, and also saved the feed of the horses.

Such an engine could be delivered in London for 100 guineas, while
a portable engine on wheels with a differently constructed boiler,
requiring no mason work, would cost 160 guineas.

 [Rough draft.]

  "GENTLEMEN,        "CORNWALL, CAMBORNE, _19th August, 1813_.

 "I have your favour of the 9th August, respecting steam-engines for
 St. Kitts. I fear it will not be possible to get an engine ready by
 the 1st of November.

 "As you say the gentleman that is about to take them out is a clever
 man, and likely to promote the use of them, I will make immediate
 inquiry, and, if possible, will get one ready, of which I will inform
 you in a short time.

 "I very much wish that every person who intends to employ a
 steam-engine of mine would first examine the engine, and be satisfied
 with the construction before giving an order, for which reason I
 must request you to send your friend down to Messrs. Hazeldine and
 Rastrick's foundry, Bridgenorth, Shropshire, where he may see the
 portable steam-engine that was made for Mr. Pickwood, which the
 founders will set to work for his inspection in half an hour after
 his arrival. As this gentleman has a taste for machines, and wishes
 to make himself fully acquainted with the principle and use of the
 steam-engine, he will be much gratified with the sight of this curious
 machine and with the information he will receive from the founders,
 which will be essentially necessary to him before leaving England.

 "I am extremely disappointed that this engine was not forwarded to Mr.
 Pickwood, as I find from his letter that he has an exceedingly clever
 and active mind, and is a very fit person to take the management of
 introducing a machine into a new country.

 "This engine is engaged by a Spanish gentleman, who is going to take
 out nine of my engines with him to Lima, in South America, in about
 six weeks.

  "I remain, your obedient servant,
  "RICHD. TREVITHICK.

  "MESSRS. PLUMMER, BARHAM, AND CO.,
  "_London_.

 "N.B.--If your friend goes to Bridgenorth, let him show this letter to
 the founders."

The engine, intended for the West Indies, so pleased Mr. Uville, that
he begged to have it made over to him for South America, where it
worked the machinery for rolling gold and silver in the Mint at Lima.

 "About 1815, while erecting a high-pressure pole-engine at Legassack
 for Mr. Trevithick, and doing some repairs to Mr. Kendal's thrashing
 engine, a Creole, I think called Nash, brought a note from Captain
 Trevithick, stating that the bearer was anxious to be taught to erect
 and work the portable engines for Jamaica.

 "Sir Rose Price, who had property in the West Indies, had sent him to
 Mr. Trevithick for that purpose."[16]

[Footnote 16: Recollections of Captain H. A. Artha, Penzance, 1869.]

It is therefore probable that some of Trevithick's engines reached
Jamaica. Sir Rose Price was well known to Lord Dedunstanville and Sir
Charles Hawkins, and living near them, saw the engines at work and
their fitness for his property in Jamaica.

Lord Dedunstanville's engine of 1812 was sold as old iron to Messrs.
Harvey and Co. not long before 1843. Having remained for some time
on the old-scrap heap, it was in that year again worked to drive
machinery. Instead of the original rope-driver on the fly-wheel, a
chain was used, the links of which caught on projecting pins on the
driving wheel. In that form it continued to work until 1853, before
which it was frequently seen by the writer prior to its removal to
make room for a more powerful engine.

What greater proof could be given of the fitness of design of this
early engine, than its long life of forty years under such rough
treatment, and the facility with which it was applied to different
uses. Mr. Bickle, who, from recollection, had made a sketch of this
engine before the writer had found Trevithick's sketch, says that after
the engine had ceased to work, the boiler was turned to account in
heating tar in the ship-builder's yard.

 "In 1854 I saw working in a shed at Carnsew, in the ship-*building
 yard of Harvey and Co., of Hayle, an engine working a stamps for
 pounding up the slag and furnace bottoms from the brass-casting
 foundry.

 "I was then the foreman hammerman in Harvey and Co.'s smiths' shop
 and hammer-mill, and frequently noticed this old engine and inquired
 about it. It had been brought from Lord Dedunstanville's, at Tehidy
 Park, where it at one time worked a thrashing machine. The boiler
 was of wrought iron, built in brickwork, and looked like a big
 kitchen-boiler. A flattish cover was bolted on to the top of the
 boiler, and the cylinder was let down into this top.

 "The cylinder had no cover; it was about 8 or 10 inches in diameter
 and 2 or 3 feet stroke. The piston was a very deep one, with a joint
 for the connecting rod which went direct to the crank, which was
 supported on two upright stands from the cover on the boiler. The
 fly-wheel had a balance-weight for the down-stroke. A pitch-chain for
 driving passed over the wheel, which had pins in it, or projections,
 to catch into the square links of the driving chain; it was worked by
 a four-way cock."[17]

 [Footnote 17: Recollections of Banfield, foreman with Harvey and Co.,
 Penzance, 1869.]

 "About 1843, when we were building iron boats for the Rhine, the old
 engine was put to work to drive the tools or machinery in the yard.
 She was very useful to us and worked very well. She worked about ten
 years, and was then thrown out to make room for a new and larger
 engine for our saw-mills. The chain-wheel for driving was made here,
 it did not belong to it originally."[18]

 [Footnote 18: Recollections of Mr. Warren, master ship-builder, Harvey
 and Co., 1869.]

 "My father (then the foreman boiler-maker) about twenty-four years ago
 took the old engine from the scrap heap, where it had been for many
 years, and set it to work in the tool shop. My father said it had come
 from Tehidy as old iron."[19]

[Footnote 19: Recollections of Mr. Burral, jun., master boiler-maker,
Harvey and Co., 1869.]

The use of the high-pressure steam agricultural engine was not confined
to Cornwall. Mr. H. Pape, still carrying on business in Hazeldine and
Rastrick's old engine manufactory at Bridgenorth, says:--

 "My father worked as a smith under Mr. Rastrick. Mr. Hazeldine had the
 foundry when Trevithick's engines were made, and have heard my father
 speak of them. I have seen three of them at work in Bridgenorth;
 one of them at Mr. Jasper's flour-mill, it drove four stones, and
 continued in work up to 1837; one at Sing's tan-yard worked up to
 1840; and one was on Mr. Jasper's farm at Stapleford for doing farm
 work. Mr. Smith, now on the farm, worked it up to about 1858.

 "The engines that worked in Bridgenorth had cast-iron cylinders for
 the outer casing of the boiler, one cylinder for small engines,
 three or four cylinders bolted together for the larger ones. The
 fire-tube was wrought iron, the chimney stood up by the fire-door.
 The cylinder was let down into the boiler; it worked with a four-way
 cock. There was a piston-rod, cross-*head, two guide-rods on the
 top of the cylinder, and two side rods to the crank and pin in 'the
 fly-wheel.'"[20]

 [Footnote 20: Recollections of Mr. William H. Pape, Bridgenorth, 13th
 June, 1869.]

 "My first husband had to do with the foundry; his father, Mr.
 Hazeldine, was a partner with Mr. Davies and Co. in 1816. In 1817 the
 partnership was broken up, and the foundry carried on by Hazeldine. I
 used to have two or three drawers full of drawings and account-books
 that were brought from the works. I kept them for many years, but now
 the greater part of them have gone to light the fire; all the drawings
 are gone."[21]

[Footnote 21: Recollections of Mrs. Marm, Bridgenorth, 12th June, 1869.]

The engines described by Mr. Pape are of the type made by Trevithick,
in Wales, about 1804, having a fire-place in the boiler, and similar in
form to the Welsh locomotive.

The drawings which served to light the fires certainly included
Trevithick's plans for the steam-locomotive, ploughing engine, the
screw-propeller, and many others of equal interest.

  "DEAR SIR,          "STABLEFORD, _March 26th, 1870_.

 "My grandfather's name was John Jasper, Esq., of Stableford; he must
 have been one, if not the first, user of a steam-engine for thrashing,
 winnowing, and shaking the straw all at one operation; it may have
 been erected eighty years ago, for an old servant of the family
 just now dead, aged ninety, worked when a boy in the steam-mill at
 Bridgenorth erected by my grandfather about the same time.

 "The thrashing engine was a side-lever engine, worked with a three
 side-way cock and tappet, a cylinder about 8-1/4 inches in diameter,
 and a 3 feet 4 inch stroke, cast-iron crank-shaft, cross-head, and
 guides. The boiler was placed underneath the engine, the fire under
 it, with brick flues. The boiler was about 9 feet long and 4 feet
 diameter.

 "The old side rods made of wood are still here, and so was the
 engine until about twelve years ago. I sent the cylinder, &c., to
 Coalbrookdale.

  "I am, Sir,
  "Yours truly,
  "THOMAS SMITH."

The Stableford agricultural engine was probably made in 1804. The
cylinder, of 8-1/4 inches in diameter, is precisely the size of that
in the Welsh locomotive, but the stroke was reduced from 4 feet 6
inches to 3 feet 4 inches, being very nearly the same as the Newcastle
locomotive. The cross-head, side rods, and boiler were very similar to
the Welsh stationary engines of that date. This engine remained in use
more than fifty years.

The engines specially referred to in this chapter fully prove, from
their length of service, the practical character of Trevithick's
inventions, and of his having persevered with his high-pressure
portables until their usefulness as locomotives and as agricultural
helps had been established; but the ploughing, though fully designed,
and probably put into practice, was not followed up to the same
approach to perfection, or the record of its progress has been lost.

Since the foregoing was written, the following has been received:--

  "DEAR SIR,        "TREWITHEN, PROBUS, _May 17th, 1872_.

 "The engine you refer to is still occasionally used here; when first
 erected there was a large quantity of corn thrashed by it, but of late
 years it has not been much used except for chaffing, bruising, &c.

  "I remain, dear Sir,
  "Yours truly,
  "WM. TRETHNOY.

  "F. TREVITHICK, Esq."

Trevithick's Trewithen engine, which sixty years ago was more
manageable than horses going momentarily faster or slower at the will
of a common labourer,[22] remains in use unchanged.

[Footnote 22: See vol. ii., p. 38.]

His preparations for South America, and application of high steam in
the large Cornish pumping engines, interfered with the perfecting the
smaller agricultural work.




CHAPTER XIX.

POLE STEAM-ENGINE.


When in the autumn of 1810 Trevithick returned to Cornwall, the
experience of ten busy years had established the practicability and
usefulness of the high-pressure engine. The principles of the invention
were now to be applied on engines of the largest size.

In 1811, the late Captain S. Grose, a young pupil of Trevithick's,
was employed to erect at Wheal Prosper Mine, in Gwythian, the first
high-pressure steam pole condensing engine. It was placed immediately
over the shaft and pump-rods, requiring no engine-beam. The air-pump,
feed-pump, and plug-rod were worked from the balance-bob. The pole was
16 inches in diameter, with a stroke of 8 feet. The boilers were two
wrought-iron tubes, 3 feet in diameter and 40 feet long. The fire was
external. Shortly after Captain H. A. Artha erected several of those
pole-engines for Trevithick. The drawing shows the simplicity of parts
of this highly expansive steam-engine, beginning the up-stroke with
steam of 100 lbs. to the inch above the atmospheric pressure, expanding
it during the stroke down to a pressure of 10 lbs., and then condensing
to form a vacuum for the down-stroke. It cost 750 guineas.

The drawings of this expansive pole condensing engine are from the
dimensions given by Captain Grose who erected it, and by Captain Artha
who knew it well.

[Illustration: WHEAL PROSPER HIGH-PRESSURE EXPANSIVE
STEAM-CONDENSING POLE-ENGINE, 1811.

_a_, cast-iron pole, 16 inches diameter, 8-feet stroke; _b_, pole-case,
a small bit larger in internal diameter than the pole; _c_, cross-head,
fixed on top of pole; _d_, guides for cross-head; _e_, side rods
connecting the two cross-heads[**typo beads corrected]; _f_, bottom
cross-head; _g_, pump-rod; _h_, balance-beam, with box for weights;
_i_, connecting rods from balance-beam to bottom cross-head; _k_,
guides for air-pump cross-head; _l_, cross-head and side rods for
working air-pump; _m_, air-pump, condenser, and water-cistern; _n_,
feed-pump worked from air-pump cross-head; _o_, plug-rod worked from
balance-beam; _p_, exhaust-valve; _q_, steam-valve; _r_, exhaust-pipe;
_s_, steam-pipe; _t_, bracket for carrying working gear; _u_, expansive
steam-horn and tappets; _v_, handles for working valves.]

[Illustration: TREVITHICK'S CYLINDRICAL BOILER FOR WHEAL PROSPER
ENGINE, 1811.

Detail of Boilers:--_a_, two wrought-iron boilers, 3 feet in diameter,
40 feet long, using steam of 100 lbs. on the square inch above the
atmosphere; _b_, cast-iron manhole door and safety-valve; _c_,
ash-pit; _d_, fire-place; _e_, flues, the fire going first the whole
length under the bottom of the boiler, then back again over the top,
and into the chimney; _f_, brickwork; _g_, ashes or other convenient
non-*conductor of heat; the fire-place ends of the boilers were 15
inches lower than the opposite ends, increasing the safety, with less
liability to prime, and greater surface for superheating.]

 "When a boy I was placed as an apprentice or learner with Captain
 Trevithick, before he left Cornwall for London. On his return to
 Cornwall, about 1810, he employed me to erect his first high-pressure
 expansive pole pumping engine at a mine in Gwythian.

 "The pole was 16 inches in diameter; the stroke was very long, but I
 do not exactly recollect the length. It had a condenser and air-pump.
 There were two boilers made of wrought iron, 8 feet in diameter and
 40 feet long. The fire was placed under them at one end, and flues
 went round them. A feed-pump forced water into the boilers; each had a
 safety-valve with a lever and weight. The steam in the boiler was 100
 lbs. to the square inch. The pole was raised by the admission of the
 strong steam under its bottom. The steam-valve was closed at an early
 part of the stroke, and the steam allowed to expand; at the end of
 the stroke it was reduced to 20 lbs. or less, when the exhaust-valve
 allowed the steam to pass to the condenser, and the pole made its
 down-stroke in vacuum. A balance-bob regulated the movement of the
 engine.

 "Trevithick's character in those days was, that he always began some
 new thing before he had finished the old."[23]

[Footnote 23: Captain Samuel Grose's recollections. 1858. Gwinear.]

Captain Artha, one of his assistants, said:--

 "I erected several of Captain Trevithick's pole-engines. My brother
 Richard worked the one at Wheal Prosper when first erected. The pole
 made an 8-feet stroke. The case was fixed over the engine-shaft on
 two beams of timber from wall to wall. A cross-head was bolted to the
 top of the pole, and from it two side rods descended to a cross-piece
 under the pole-case, from which the pump-rod went into the shaft.
 A connecting rod worked a balance-beam, which worked the air-pump,
 feed-pump, and plug-rod for moving the valves. The steam, of a very
 high pressure, worked expansively."[24]

[Footnote 24: Captain H. A. Artha's recollections. Penzance, 1869.]

The first admission of the high-pressure steam under the pole was equal
to a force of 8 or 9 tons, causing it and its attached pump-rods to
take a rapid upward spring. Having travelled 1 or 2 feet of its stroke
of 8 feet, the further supply of steam from the boiler was cut off, and
its expansion, together with the momentum of the mass of pump-rods,
completed the upward stroke. The pressure of the steam in the pole-case
at the finish of the up-stroke would be reduced to say 10 or 20 lbs.
to the inch, according to the amount of work on the engine. The steam
then passed to the condenser and air-pump, and the engine made its
down-stroke by the vacuum under the pole, and by the weight of the
descending pole and pump-rods.

Each boiler was a wrought-iron tube 3 feet in diameter and 40 feet
long, the fire-place under one end, with brick flues carrying the
heated air under the whole length of the bottom of the boiler, and back
again over the top or steam portion for superheating.

 [Rough draft.]

  "CAMBORNE, _28th February, 1813_.

 "I will engage to erect a puffer steam-engine, everything complete at
 the surface, on the Cost-all-lost Mine, capable of lifting an 8-inch
 bucket, 4-1/2-feet stroke, twenty-four strokes per minute, 30 fathoms
 deep, or 280 gallons of water per minute from that same depth, being a
 duty equal thereto, for 550 guineas. But if a condensing engine, 600
 guineas. If of the same size as Wheal Prosper, 750 guineas.

  "RICHARD TREVITHICK."

The engines, erected in 1811 or 1812, combined the novelty of the
steam pole-engine, with the use of high-pressure steam of 100 lbs.
on the square inch, and the comparatively untried principle of steam
expansion, carried to what in the present day is thought an extreme and
unmanageable limit.

The Wheal Prosper engine fixed near the sea-shore at Gwythian is
referred to in Trevithick's note to Mr. Rastrick,[25] as "that new
engine you saw near the sea-side, with me, is now lifting forty
millions, 1 foot high, with 1 bushel of coal" (84 lbs.), "which is very
nearly double the duty that is done by any other engine in the county."

[Footnote 25: See Trevithick's letter, January 26th, 1813, chap, xviii.]

This was probably the first application of high-pressure steam to give
motion to pump-rods. The engine, as compared with the neighbouring
Watt low-pressure steam vacuum pumping engines, was small, but the
principles of high steam, expansive working, and vacuum, were combined
successfully to an extent scarcely ventured on by modern engineers.

Trevithick's high-pressure condensing whim-engines had been for some
years at work in Cornwall, but mine adventurers had not dared to risk
the application of high-pressure steam to the large pumping engines,
fearing its great power would prove unmanageable, and its rapid
movement cause breakage of the pump-rods and valves.

Two distinct inventions or improvements, each of which was actually
followed up in different mines, show themselves in this engine: one
being the form of boiler to give with economy and safety high-pressure
expansive steam for large engines; the other, the application of a
pole in lieu of a piston, as a more simple engine for working with
strong expansive steam, and more easily constructed by inexperienced
mechanics, who had none of the slide lathes or planing machines so much
used by engine builders of the present day.

 "About 1814 Captain Trevithick erected a large high-pressure
 steam-puffer pumping engine at the Herland Mine. The pole was about 30
 inches in diameter, and 10 or 12 feet stroke. There was a cross-head
 on the top of the pole, and side rods to a cross-head under the
 pole-case. The side rods worked in guides. The pole-case was fixed to
 strong beams immediately over the pump-shaft. The steam was turned
 on and off by a four-way cock. The pressure was 150 lbs. to the inch
 above the atmosphere. The boilers were of wrought iron, cylindrical,
 about 5 feet 6 inches in diameter and 40 feet long, with an internal
 tube 3 ft. in diameter. The fire-place was in the tube. The return
 draught passed through external brick flues.[26]

 [Footnote 26: Recollections of the late Captain Charles Thomas, manager
 of Dolcoath Mine.]

 "When a young man, living on a farm at Gurlyn, I was sent to Gwinear
 to bring home six or seven bullocks. Herland Mine was not much out
 of my way, so I drove the bullocks across Herland Common toward the
 engine-house. Just as the bullocks came near the engine-house the
 engine was put to work. The steam roared like thunder through an
 underground pipe about 50 feet long, and then went off like a gun
 every stroke of the engine. The bullocks galloped off--some one way
 and some another. I went into the engine-house. The engine was a great
 pole about 3 feet in diameter and 12 feet long. A cast-iron cross-head
 was bolted to the top of the pole. It had side rods and guides. A
 piece of iron sticking out from the cross-head carried the plug-rod
 for working the gear-handles. The top of the pole worked in a stuffing
 box. A large balance-beam was attached to the pump-rods, near the
 bottom cross-head.

 "There were two or three of Captain Trevithick's boilers with a tube
 through them, the fire in the tube. They seemed to be placed in a pit
 in the ground. The brick flues and top of the bricks were covered with
 ashes just level with the ground. A great cloud of steam came from the
 covering of ashes.

 "I should think the pressure was more than 100 lbs. to the inch.
 People used to say that she forked the mine better than two of Boulton
 and Watt's 80-inch cylinder engines. We could hear the puffer blowing
 at Gurlyn, five or six miles from the Herland Mine.

 "In 1813 I carried rivets to make Captain Trevithick's boilers in the
 Mellinear Mine; they were 5 feet in diameter and 30 or 40 feet long,
 with an internal fire-tube. It took four or five months to build them.
 In the present day (1869) a fortnight would build them. The largest
 boiler-plates obtainable were 3 feet by 1 foot. We had to hammer them
 into the proper curve. The rivet-holes were not opposite one another.
 A light hammer was held against the rivet-head in riveting, in place
 of the present heavy one, so the rivet used to slip about, and the
 plates were never hammered home so as to make a tight joint."[27]

[Footnote 27: Recollections of Mr. James Banfield, Penzance, 1871.]

Lest the reader should doubt the comparative power of the Watt
low-pressure vacuum and Trevithick's high-pressure steam-engines, a
short but sufficiently close calculation shows that taking Stuart's[28]
estimate of the effective power of the Watt engine at 8-1/2 lbs. on
each square inch of the piston, and Trevithick's engine at anything
approaching to 150 lbs. on each square inch, it becomes evident that
the latter would be ten or twenty times more powerful than the former.
A few figures will put the question in more practical form.

[Footnote 28: See Stuart's 'History of the Steam-Engine.']

The Wheal Prosper 16-inch pole high-pressure expansive steam vacuum
engine commenced its up-stroke with steam of 100 lbs. on the inch,
acting on the 122 square inches of the pole, which steam at the
finish of the stroke was reduced by expansion to 10 lbs., giving,
say, an average steam pressure of 55 lbs. The down-stroke was caused
by a vacuum under the pole of 14 lbs. on the inch, reduced by,
say, one-third loss in working the air-pump to 9 lbs., giving from
the compound stroke a force of 64 lbs. on each square inch, which,
multiplied by the area of the pole, gives a net force of 7808 lbs.

The Herland 33-inch pole high-pressure expansive steam puffer-engine
commenced its up-stroke with steam of 150 lbs. on the inch, acting on
the 855 square inches of the pole, which steam at the finish of the
stroke--we will suppose--was reduced by expansion to 75 lbs., giving
an average steam pressure of, say, 112. As this puffer-engine used
no vacuum, the down-stroke gave no increase of power; its compound
stroke was therefore a force of 112 lbs. on each square inch, which,
multiplied by the area of the pole, gives a net force of 95,760 lbs.

To compare the Trevithick high-pressure steam pumping engine, with
the Watt low-pressure steam pumping engine, take one of the largest
of the latter, made about that time, say, with an 80-inch cylinder,
which commenced its down-stroke with steam of, say, 3 lbs. on the
inch, acting on the 5000 square inches of the piston, which steam at
the finish of the stroke--the writer is describing the usage at that
time, for Watt himself advocated a less steam pressure--was reduced by
expansion to, say, 1 lb., giving an average steam pressure of, say, 2
lbs. on the top of the piston, whose under side was in vacuum equal to
14 lbs. on the inch, reduced by, say, one-third loss in working the
air-pump to 9 lbs., which power, from vacuum added to the 2 lbs. from
steam, gives a net force of 11 lbs. on each square inch of the piston.
As the Watt pumping engine moved in equilibrium during its up-stroke,
it thereby gained no increase of power; its compound stroke was
therefore a force of 11 lbs. on each square inch, which, multiplied by
the area of the piston, gives a net force of 55,000 lbs.

The practical comparison therefore stands,--Trevithick's 16-inch pole
high-pressure steam, and vacuum, on each inch 64 lbs., net force 7808
lbs.; Trevithick's 33-inch pole high-pressure steam, without vacuum,
on each inch 112 lbs., net force 95,760 lbs.; Watt's 80-inch piston,
low-pressure steam, and vacuum, on each inch 11 lbs., net force 55,000
lbs. As the first cost was mainly dependent on the size, the Trevithick
engine was commercially much more valuable than the Watt engine.

 "I saw Captain Trevithick's puffer working at the Herland Mine. The
 steam used to blow off like blue fire--it was so strong. The lever on
 the safety-valve was about 3 feet long, with a great weight on it,
 more than a hundredweight. The engine did not answer very well, for
 the packing in the pole stuffing box used to burn out, and a cloud
 of steam escaped. The greatest difficulty was in the leaking of the
 boilers. You could hardly go near them. Before that time we always
 put rope-yarn between the lap of the boiler-plates to make the seams
 tight. Captain Dick's high-pressure steam burnt it all out. He said,
 'Now you shall never make another boiler for me with rope-yarn.'
 Everybody said it was impossible to make a tight boiler without it.
 We put barrowfuls of horse-dung and bran in Captain Dick's boilers to
 stop the leaks."[29]

[Footnote 29: Henry Clark of Redruth, in 1869, aged eighty-three years.]

This difficulty of making a tight and safe boiler, that puzzled Watt,
was moonshine to Trevithick. When the strained boiler and flinching
rivets allowed the boiler-house to become full of dense steam,
Trevithick told them to cover it up with ashes, they would not see it
quite so much then, and it would keep the heat in the boiler. Bran or
horse-dung inside was a good thing as a stop-gap, though it added not
to the strength of the boiler. Trevithick was himself in a cloud of
steam in the engine-house; yet, with such surroundings, he turned on
and off his gunpowder steam, from his cannon of a pole-case, of 40 tons
force, sending his bolt-shot pole, 33 inches in diameter, its destined
course of ten feet, and back again, as though it were a shuttlecock,
several times in a minute.

Having by one or two years of experience proved the value of his
new pole-engine, he applied for a patent on the 13th June, 1815,[30]
of which the following is the portion referring particularly to the
pole-engine:--

[Footnote 30: See full copy of patent, chap. xvi.]

 "Instead of a piston working in the main cylinder of the steam-engine,
 I do use a plunger-pole similar to those employed in pumps for lifting
 water, and I do make the said plunger-pole nearly of the same diameter
 as the working cylinder, having only space enough between the pole
 and the cylinder to prevent friction, or, in case the steam is
 admitted near the stuffing box, I leave sufficient room for the steam
 to pass to the bottom of the cylinder, and I do make at the upper
 end of the cylinder for the plunger-pole to pass through a stuffing
 box of much greater depth than usual, into which stuffing box I do
 introduce enough of the usual packing to fill it one-third high. Upon
 this packing I place a ring of metal, occupying about another third
 part of the depth of the stuffing box, this ring having a circular
 groove at the inside, and a hole or holes through it communicating
 with the outside, and with a hole through the side of the stuffing
 box; or, instead of one ring containing a groove, I sometimes place
 two thinner rings, kept asunder by a number of pillars to about the
 distance of one-third of the depth of the stuffing box, and I pack the
 remaining space above the ring or rings, and secure the whole down
 in the usual manner. The intention of this arrangement is to produce
 the effect of two stuffing boxes, allowing a space between the two
 stuffings for water to pass freely in from the boiler or forcing pump
 through a pipe and through the hole in the side of the stuffing box,
 so as to surround the plunger-pole and form the ring of water for the
 purpose of preventing the escape of steam by keeping up an equilibrium
 between the water above the lower stuffing and the steam in the
 cylinder. By this part of my said invention I obviate the necessity of
 that tight packing which is requisite when steam of a high pressure
 is used, and consequently I avoid a greater proportion of the usual
 friction, because a very moderate degree of tightness in the packing
 is quite sufficient to prevent the passage of any injurious quantity
 of so dense a fluid as water. And I do further declare that I use the
 plunger-pole, working in a cylinder and through a double stuffing,
 either with or without a condenser, according to the nature of the
 work which the steam-engine is to perform."

Though Trevithick has been spoken of as a visionary, intractable
schemer, observation shows that he adhered with tenacity to original
ideas, proved to be good. The plunger-pole pump, the water-pressure
engine, the Camborne locomotive, the pole steam-engine, were all built
on the same groundwork originally started with, of greatest simplicity
of form, and absence of many pieces; and it may be observed that he
never applied for a patent until the value of the idea had been proved
by experiment.

In practice the difficulty of keeping the pole-packing in order was
one of the objections to the plan; for it either leaked, or, if packed
tight, caused much friction and wearing away of the middle of the pole
faster than the ends, from the greater speed at the middle of the
stroke. The steam-ring was therefore of importance in the engine, in
those days of inaccurate workmanship; like the water cup on the gland
of the plunger-pump packing, it prevented external air from injuring
the vacuum.

  "MR. GIDDY,            "CAMBORNE, _July 8th, 1815_.

 "Sir,--About a fortnight since I received letters from Lima, and also
 letters to the friends of the men who sailed with the engines. They
 arrived on the 29th January, after a very good passage, and without
 one hour's sickness. Both their and my agreements were immediately
 ratified, and they are in high spirits. The ship finished discharging
 on the 11th February, which was the day those letters sailed from Lima
 with $12,000 for me, which has all arrived safe.

 "I shall make another fit-out for them immediately. I expect that all
 the engines will be at work before the end of October; half of them
 must be at work before this time. The next day, after their letters
 sailed for Europe, they intended to go back to the mines. Woolf's
 engine is stopped at Herland, and I have orders to proceed. A great
 part of the work is finished for them, and will be at work within two
 months from the time I began. I only engage that the engine shall
 be equal to a B. and Watt's 72-inch single, but it will be equal to
 a double 72-inch cylinder. It is a cast-iron plunger-pole, over the
 shaft, of 33 inches diameter, 10-feet stroke. The boiler is two
 tubes, 45 feet long each, 3 feet diameter, 1/2 an inch thick, of
 wrought iron, side by side, nearly horizontal, only 15 inches higher
 at the steam end of the tubes, to allow the free passage of steam to
 the steam-pipe. There are two 4-inch valves, one the steam-valve,
 the other the discharging valve. I have made the plunger-case and
 steam-vessel of wrought iron 3/4 of an inch thick. The steam-vessel
 is 48 inches in diameter. The plunger stands on beams over the shaft,
 with the top of it at the level of the surface, with a short T-piece
 above the plunger-pole, and a side rod on each side, that comes up
 between the two plunger-beams in the shaft; this does away with the
 use of an engine-beam, and the plungers do away with the use of a
 balance-beam.

[Illustration: POLE-ENGINE.]

 "The fire is under the two tubes, and goes under them for 45 feet, and
 then returns again over them, and then up the chimney. Those tubes
 need no boiler-house, because they are arched over with brick, which
 keeps them from the weather, and scarcely any engine-house is needed,
 only just to cover the engineman.

 "Suppose a 72-inch cylinder (having 4000 inches), at 10 lbs. to the
 inch, an 8-feet stroke, working nine strokes per minute (which is more
 strokes of that length than she will make when loaded to 10 lbs. to
 the inch).

  Inches.
     4000 in a 72-inch cylinder, single.
       10 lbs. to the inch.
  -------
    40000
        8 feet stroke.
  -------
   320000
        9 strokes per minute.
  -------
  2880000 lbs. lifted one foot high per minute.
  -------

 "Suppose a 33-inch plunger-pole, 10-feet stroke, ten strokes per
 minute (which is not so fast by three or four strokes per minute as
 this engine will go, because she will have no heavy beam to return,
 neither will she have to wait for condensing, like B. and Watt's,
 which, when loaded, hangs very long on the injection).

      855 square inches in a 33-inch plunger-pole.
       10 strokes per minute.
  -------
     8550
       10 feet stroke.
  -------
    85500
       34 lbs. to the inch, real duty.
  -------
   342000
  256500
  -------
  2907000 lbs. lifted one foot high per minute.
  -------

 "I should judge that less than 50 lbs. to the inch above the
 atmosphere would be quite enough to do the work of a 72-inch cylinder
 single, which is but a trifle for those wrought-iron tubes to stand.
 This engine, everything new, house included, ready for work, will
 not exceed 700_l._ Two months are sufficient for erecting it. The
 engine of Woolf's, at Wheal Vor, which is but two-thirds the power of
 a 72-inch cylinder, single power, cost 8000_l._, and was two years
 erecting. I would be much obliged to you for your opinion on this
 business.

  "I remain, Sir,
  "Your very humble servant,
  "Richard Trevithick.

 "I am sorry to say that the mines in general are very poor."

He shows that with steam of 34 lbs. to the inch, his Herland pole
puffer steam-engine of 33 inches in diameter would be equal in power
to the Watt low-pressure steam vacuum engine, with a 72-inch cylinder.
Herland, like Dolcoath and Wheal Treasury, was the chosen battle-ground
of rival engineers; fifty years after Newcomen had there erected
his famously large 70-inch cylinder engine, Watt surpassed it in
size by a cylinder 2 inches more in diameter, and, after personally
superintending its erection in 1798, declared that "it could not be
improved on." Mr. Davey, the mine manager, considered that it did
twenty millions of duty, though Mr. Watt had made it twenty-seven
millions with a bushel of coal.[31] This difference is probably
explained by the then Cornish bushel weighing 84 lbs., while Watt
generally calculated a bushel at 112 lbs.

[Footnote 31: Lean's 'Historical Statement of the Steam-Engine,' p. 7.]

Trevithick declining to believe Watt's prognostication, a public test
of Watt's engines in the county was demanded; Mr. Davies Gilbert,
with Mr. Jenkin, were requested to report on their duty, and gave it
in 1798 as averaging seventeen millions.[32] During the same year the
adventurers in Herland Mine engaged Trevithick and Bull, jun., to erect
a 60-inch cylinder Bull engine to compete with Watt's 72-inch cylinder.
The result of this fight is not traceable, nor what took place there
during the succeeding fifteen years; when in 1814 Woolf erected in
Cornwall his double-cylinder engine to compete with Watt's engine,
and Trevithick attacked them both with his Herland high-pressure pole
puffer in 1815, when he erected at his own risk and cost a 33-inch
pole-engine, engaging that it should, both in power and economical
duty, equal the Watt 72-inch engine. The boilers were similar in form
to those used a year before in Wheal Prosper high-pressure steam vacuum
pole-engine, being two wrought-iron tubes, each 45 feet long and 3
feet in diameter, made of plates half an inch thick. The fire was in
external flues. The engine was fixed directly over the pump-rods in the
shaft, using neither main beam nor air-pump.

[Footnote 32: Lean's 'Historical Statement of the Steam-Engine,' p. 7.]

Trevithick's rough hand-sketch shows the steam-ring in the stuffing
box and the steam-vessel; the particular use of the latter he has not
described: probably it was because Cornish pumping engines, not having
the controlling crank to limit the movement of the piston, are obliged
to trust to the very admirable, but little understood, steam-cushion,
without which the ascending piston would inevitably strike and break
the cylinder-cover, while in the pole puffer-engine this danger was
during the descent of the pole, and therefore the discharge-steam valve
was closed, while the steam in the pole-case was still of ten or more
pounds to the inch, so that by the time the pole reached the finish of
its down-stroke, it had compressed this steam-cushion, filling also
the steam-vessel, with a pressure approaching to that in the boiler,
and equal to the weight of the pole and pump-rods. A comparatively
small supply of steam from the boiler into the steam-vessel brought
it up to the boiler pressure, sending the pole and pump-rods upwards
with a spring. The steam-valve then closed, allowing the momentum of
the great weight of pump-rods, together with the expanding steam, to
complete the up-stroke. The discharge-valve was then opened for a
moment, allowing a blast of steam to escape, reducing the pressure say
to one-half. The weight of the rods caused their downward movement,
raising the load of water in the plunger-pole pumps, and at the same
time compressing the steam from the pole-case into the steam-vessel,
equal at the finish of the stroke to the support of the pole and
pump-rods. This most simple steam-engine combined in the greatest
degree the two elements of expansion and momentum.

The up-stroke began with a much higher pressure of steam than was
necessary to raise the load; having given momentum to the rods,
the supply of steam was cut off, and the stroke was completed by
expansion. The down-stroke began with a comparatively low pressure
of steam under the pole. The unsupported pump-rods fell downwards,
setting in upward motion the column of water in the plunger-pole
pumps. The discharge-valve was closed long before the completion of
the down-stroke, and the momentum of the moving mass of rods and water
compressed the steam driven from the pole-case into the steam-vessel up
to a pressure equal to the support of the pole and pump-rods. The pole
was, therefore, continually floating or rising and falling in steam of
ever-varying pressure.

Trevithick' s figures show the working power of the 33-inch pole
as much greater than Watt's 72-inch cylinder engine, even when the
steam pressure in the former was much reduced, and that Woolf's
double-cylinder engine, of less power, cost ten times as much as the
pole-engine. This sum probably included the costly buildings required
for the beam-engines, which Trevithick's plan dispensed with.

The reader may judge of the perfection of mechanism in this
plain-looking engine from the fact that a pole, with 150 lbs. of steam
to the inch in the boiler, was equal to 50 or 60 tons weight, thrown
up and down its 10-feet stroke ten or fourteen times a minute, with
a limit of movement perfectly under control, while modern engineers
are building ships' turrets because of the difficulty of raising and
depressing a 30-ton gun from the hold to above the water level.

 [Rough draft.]

  "SIR,             "CAMBORNE, _September 12th, 1815_.

 "I received a letter dated the 20th of August, from Mr. Davies, in
 which he did not mention the name of Herland castings. On the 24th
 of the same month I wrote to you, informing you of the same, and
 requesting to know what state of forwardness the castings were in.
 On the 30th of August I received another letter from Mr. Davies, not
 saying what state of forwardness the castings were in, nor when they
 would be finished, only that they would set their hands about them,
 and that I might expect a letter from you stating the particulars,
 which has not yet come to hand. I have waited so long that I am quite
 out of patience. You will know that it is now nearly double the time
 that the castings were to have been finished in, and you have not yet
 answered my letters as to the state of the castings nor when they will
 be finished. I must again request you to write to me on this subject,
 otherwise I must immediately remove the orders to some other founders
 that may be a little more attentive to their customers. I must be
 informed in the positive, whether the castings will be at Bristol by
 the next spring-tide, as a vessel is engaged for the purpose of taking
 them to Cornwall.

  "Yours, &c.,
  "R. T.

  "MR. JOHN RASTRICK,
  "_Chepstow, South Wales_."

Rastrick, whom he had known at the Thames Driftway, had become the
managing engineer at the Bridgenorth Foundry.

 [Rough draft.]

  "MR. GEORGE COWIE,     "CAMBORNE, _September 29th, 1815_.

 "I received your favour of the 20th, and on the 23rd called on Mr. Wm.
 Sims, your engineer, who went with me to Beeralstone Mine the same
 day. We arranged on the spot what was necessary for the engine. I hope
 it will be at work in good time, before the winter's floods set in.
 Nothing can prevent it, unless the castings are detained by contrary
 winds. The boilers are nearly finished in Cornwall. The castings at
 Bridgenorth are in a forward state. I intend leaving this evening for
 Bridgenorth, to ship the castings, both for Herland and Beeralstone.
 It was the wish of the agents on the mine that these castings might be
 sent to Swansea, and taken from thence to the mine with a freight of
 coal. I shall, if possible, get the Herland castings in the same ship.
 The workmen making your boilers want an advance of cash to enable
 them to finish. They provide both iron and labour, for which they are
 to receive 42_l._ per ton for the boiler when finished; the weight
 will be about 8 tons. You may send this money to Mr. Sims or to me,
 or otherwise you may direct it to Mr. N. Holman, boiler-maker, Pool,
 near Truro. 100_l._ will satisfy them for the present. I hope to be in
 London this day week, and will call at your office.

  "Yours, &c.,
  "R. TREVITHICK."

The pole-engine was not only used in several mines shortly after
its first introduction, but Mr. Sims, the leading engineer of the
eastern mines, not generally favourable to Trevithick, advocated its
application in the traditional Watt district.

Scarcely had he smoothed the way with one opponent than another sprung
up in an unexpected quarter. His brother-in-law, Harvey, with his once
friend, Andrew Vivian, then a partner with Harvey, opposed his plans at
the Herland. They were annoyed at Trevithick's sending his orders for
castings and machinery to Bridgenorth, and may have had doubts of the
success of the new inventions. They had authority in the mine, probably
as shareholders, a position generally acquired in Cornwall by those
who supply necessary mine material, as well as by the smelters who
buy the mineral from the mines. The Williamses and Foxes, controlling
the eastern district of mines, were also shareholders and managers,
supplying machinery and buying the mine produce.

 [Rough draft.]

  "SIR,              "PENZANCE, _13th December, 1815_.

 "Yesterday I was at Herland, where I was informed that Captain Andrew
 Vivian had been the day before, on his return from Mr. Harvey's, and
 discharged all the men on the mine, without giving them a moment's
 notice. Before the arrival of the castings the pitmen, sumpmen,
 carpenters, and smiths were very busy getting the pit-work ready; at
 which time H. Harvey and A. Vivian were exulting in reporting that the
 iron ore was not yet raised that was to make the Herland castings.
 The day that they heard of their arrival they discharged all the
 labourers, and ordered the agents not to admit another sixpence-worth
 of materials on the adventurers' account, or employ any person
 whatever.

 "The agents sent a short time since to Perran Foundry[33] for the iron
 saddles and brasses belonging to the balance-bob, the property of
 the adventurers; but they refused to make them, with a great deal of
 ill-natured language about my engine.

 [Footnote 33: Belonging to Williams and Co.]

 "I am determined to fulfil my engagement with the adventurers, and
 yesterday ordered all the smiths, carpenters, pitmen, and sumpmen to
 prepare the adventurers' pit-work, and ordered the agents to get the
 balance-bob and every other thing that may be wanted at my expense, so
 as to fork the first lift, which I hope to have dry by Monday three
 weeks. The engine will be in the mine this week, and in one fortnight
 after I hope the engine will be at work, and in less than a week more
 the first twenty fathoms under the adit will be dry.

 "In consequence of the Perran people refusing to send the saddles
 and brasses for the balance-bob, we will make shift in the best way
 we can without them. The brasses I have ordered on my own account at
 Mr. Scantlebury's. The coals for the smiths I have also ordered, and
 the same for the engine to fork the first lift. This is very uncivil
 treatment in return for inventing and bringing to the public, at my
 own risk and expense, what I believe the country could not exist
 without. I am determined to erect the engine at all events and upset
 this coalition before I leave Europe, if it detains me one year to
 accomplish it.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK.

  "MR. PHILLIP,
  "_George Yard, Lombard Street_.

 "P.S.--I should be glad to hear from you what is going forward
 respecting an arrangement of the shares."

 [Rough draft.]

  "GENTLEMEN,        "PENZANCE, _23rd December, 1815_.

 "I have received the Herland castings, and am very seriously sorry to
 say, after we had fixed together the castings on the mine and made the
 joints, on attempting to put the plunger-pole into the case it would
 not go down; neither would either of the rings go to their places into
 the cylinder and on to the pole; therefore the whole engine must be
 again taken to pieces and sent to a turning and boring mill to be
 newly turned and bored. How to get this done I cannot tell, for the
 founders here will not do it because they had not the casting them.
 Already great expenses have been incurred by delays, and now to send
 them back to Bridgenorth at an immense loss of time and money will be
 a very serious business indeed. I think that either the cylinder is
 bored crooked or the plunger-pole turned crooked, or both, as it will
 sink farther down into the cylinder on turning it round on one side
 than it will on the other. The whole job is most shamefully fitted up,
 and was never tried together before sent off. Write to me by return of
 post and say what I am to do in this dilemma.

  "Yours, &c.,
  "RICHARD TREVITHICK.

  "HAZELDINE, RASTRICK, AND CO.,
  "_Bridgenorth_."

The new engine-work from Bridgenorth on arrival was found to be so
inaccurately made that the pole would not go into the pole-case. Henry
Phillips,[34] who saw the engine make its first start, says:--

[Footnote 34: Still working in Harvey's foundry at Hayle, 1869.]

 "I was a boy working in the mine, and several of us peeped in at the
 door to see what was doing. Captain Dick was in a great way, the
 engine would not start; after a bit Captain Dick threw himself down
 upon the floor of the engine-house, and there he lay upon his back;
 then up he jumped, and snatched a sledge-hammer out of the hands of a
 man who was driving in a wedge, and lashed it home in a minute. There
 never was a man could use a sledge like Captain Dick; he was as strong
 as a bull. Then, he picked up a spanner and unscrewed something, and
 off she went. Captain Vivian was near me, looking in at the doorway;
 Captain Dick saw him, and shaking his fist, said: 'If you come in here
 I'll throw you down the shaft.' I suppose Captain Vivian had something
 to do with making the boilers, and Captain Dick was angry because they
 leaked clouds of steam. You could hardly see, or hear anybody speak in
 the engine-house, it was so full of steam and noise; we could hear
 the steam-puffer roaring at St. Erth, more than three miles off."

By the end of January, 1816, the engine was ready for work, and after
ten days of experience, he thus described the result:--

  "MR. DAVIES GIDDY, M.P.,    "PENZANCE, _11th February, 1816_.

 Sir,--I was unwilling to write you until I had made a little trial
 of the Herland engine. It has been at work about ten days, and works
 exceedingly well; everyone who has seen it is satisfied that it is
 the best engine ever erected. It goes more smoothly than any engine I
 ever saw, and is very easy and regular in its stroke. It's a 33-inch
 cylinder, 10-1/2-feet stroke. We have driven it eighteen strokes per
 minute. In the middle, or about two-thirds of the stroke, it moved
 about 8 feet per second, with a matter in motion of 24 tons; and
 that weight returned thirty-six times in a minute, with 2 bushels
 of coal per hour. This of itself, without the friction, or load of
 water, is far more duty than ever was done before by an engine. I
 found that it required about 80 lbs. to the inch to work the engine
 the first twelve hours, going one-third expansive, twelve strokes
 per minute, 10-1/2-feet stroke, with 24 bushels of coal. The load of
 water was about 30,000. This was occasioned by the extreme friction,
 the plunger-pole being turned, and the plunger-case bored, to fit so
 nicely from end to end, that it was with great difficulty we could at
 all force the plunger-pole down to the bottom of the plunger-case.
 This is now in a great degree removed, and since we went to work we
 have thrown into the balance-box 4 tons of balance, and it would
 carry 3 tons more at this time. We must have carried that load in
 friction against the engine, therefore, if you calculate this, you
 will find it did an immense duty, going twelve strokes per minute,
 10-1/2-feet stroke, with 2 bushels of coal per hour. The engine is now
 working regularly twelve strokes per minute, with 60 lbs. of steam,
 10-1/2-feet stroke, three-quarters of the stroke expansive, and ends
 with the steam rather under atmosphere strong, with considerably
 within 2 bushels of coal per hour. I would drive her faster, but as
 the lift is hanging in the capstan rope under water, they are not
 willing to risk it. I have raised the steam to 120 lbs. to the inch,
 the joints and everything perfectly tight. I took the packing out of
 the stuffing box and examined it, and found that the heat had not at
 all injured it; the packing is perfectly tight, not a particle of
 steam is lost.

 "I have offered to deposit 1000_l._ to 500_l._ as a bet against
 Woolf's best engine, and give him twenty millions, but that party
 refuses to accept the challenge. I have no doubt but that by the time
 she is in fork she will do 100 millions, which is the general opinion
 here. The boilers are certainly the best ever invented, as well as
 the other parts. The draught is the best you ever saw; I have only
 one-quarter part of the fire-bars uncovered, yet from one-quarter
 part of the fire-place that I first made, I find plenty of steam.
 The greatest part of the waste steam is condensed in heating the
 water to fill the boiler; what escapes is a mere nothing. The engine
 will be loaded, when in fork, about 52 lbs. to the inch. Now suppose
 I raise the steam so high at the first part of the stroke as to go
 so expansive as to leave the steam, at the finish, only atmosphere
 strong, shall I, in that case, use any more coal than at present? The
 materials and joints will stand far more than that pressure; 500 lbs.
 to the inch would not injure them. When the engine gets on two lifts,
 I will write to you again, and in the meantime please to give me your
 thoughts on the engine. Every engine that was erecting is stopped, and
 the whole county thinks of no other engine.

  "Your very obedient servant,
  "RD. TREVITHICK."

The new pole puffer-engine worked so satisfactorily and its movements
were so manageable that the length of the stroke was increased by the
spare 6 inches, which had been allowed as a margin in case of its
overrunning its intended stroke. It would bear being worked at eighteen
strokes a minute, while the Watt 72-inch engine did not exceed nine
strokes a minute; with steam in the boiler of 80 lbs. to the inch it
performed its work when the steam supply was cut off at two-thirds of
the stroke, completing it by expansion. It also worked well with steam
of 120 lbs. to the inch; but the want of strength in the pump-rods and
the requirements of the mine caused the regular working pressure of
steam to be reduced to 60 lbs. on the inch, and to be cut off when the
pole had moved through the first quarter of its stroke. The excellent
draught causing the fire-bars to be reduced to one-quarter of their
original surface, and the heating the feed-water by the waste steam
in this powerful pumping engine, indicate the use of the blast-pipe
as at that time worked in the Welsh puddling-mill engine. Watt's
engine was for a moment forgotten, that he might challenge Woolf to a
trial, giving him as a help twenty millions, or the understood duty
of the Watt engine. This non-condensing pole-engine, with 20 tons of
pump-rods, moved at a maximum speed of 8 feet a second, and was equal
to its work with a steam pressure of 52 lbs. on the inch. Trevithick
contemplated extending the expansive principle even further than he
had done in the Wheal Prosper pole condensing engine, so that at the
finish of the up-stroke the steam should only be about the pressure of
the atmosphere, or say from 1 to 10 lbs. on the inch, having commenced
it with steam of from 100 to 200 lbs. on the inch, and cutting off the
supply from the boiler when the pole had gone but a very small part of
its upward stroke, more or less as the mine requirements admitted of
it. The principle of expansive working and momentum of moving parts was
of necessity modified in its application to pump-work.

  "DEAR TREVITHICK, "EASTBOURNE, _February 15th, 1816_.

 "I have been called here by the decease of my wife's uncle, and
 consequently your letters of the 11th did not reach me till this day.

 "The account you give me of your new engine has been extremely
 gratifying. The duty performed by the engine in giving a velocity
 of 8 feet in a second, thirty-six different times in a minute, to
 24 tons of matter, by the consumption of 2 bushels of coal in an
 hour, is indeed very great, amounting to about fifty-seven and
 three-quarter millions. So that when you obtain a proper burden, and
 the extraordinary friction arising from the too close fitting of the
 plunger-pole and case is reduced, there seems to be no doubt of your
 engine performing wonders.

 "I am of opinion that the stronger steam is used, the more
 advantageous it will be found. To what degree it should be applied
 expansively must be determined by experience in different cases. It
 will depend on the rate at which the engine requires to be worked, and
 on the quantity of matter put into motion, so that as large a portion
 as possible of the inertia given in the beginning of the stroke may be
 taken out of it at the end.

 "Some recent experiments made in France prove, as I am told, for I
 have not seen them, that very little heat is consumed in raising the
 temperature of steam. And if this is true, of course there must be a
 great saving of fuel by using steam of several atmospheres' strength,
 and working expansive through a large portion of the cylinder. I have
 really been impatient for a week past to receive some account of your
 machine, having learned nothing about it, except from a paragraph
 dated Hayle in the Truro paper of last Saturday week, and somehow or
 other the next paper has not reached me,

 "I hope to be in London about Tuesday next, but at all events direct
 to me there, as my letters are regularly forwarded.

  "Believe me, dear Sir,
  "Yours ever most faithfully,
  "DAVIES GIDDY."

 [Rough draft,]

  "MR. JOHN ADAMS,      "BROMSGROVE, _8th March, 1816_.

 "Sir,--I received your favour of the 12th February, but did not answer
 it in due course, because I was then erecting an engine on the new
 plan, which is now at work, and performs exceedingly well. It is equal
 in power to a 72-inch diameter cylinder, double power of B. and
 Watt's. The expense of erection, and the consumption of coals in this
 engine, are not one-third of a B. and Watt's to perform the same work.
 I am the same Trevithick that invented the high-pressure engine. I
 have sent out nine steam-engines to the gold and silver mines of Peru.
 I intend to sail for that place in about a month or six weeks, but
 shall appoint agents in England to erect these engines.

 "No publication or description whatever has been in circulation,
 neither is it required, for I have a great many more orders than I can
 execute.

 "I have not seen anything of Mr. Losh's patent engine, or Mr. Collins'.

 "If you should go to London I advise you to call on Mr. Jas. Smith,
 Limekiln Lane, Greenwich, who is an agent for me, and will soon be
 able to show you an engine on this plan at work.

  "I remain, &c.,
  "R. TREVITHICK."

Unless the foregoing letters are based on error, the only conclusion
to be drawn is that Watt, on the expiry of his patent right and
of twenty-eight years of labour, having erected his masterpiece
in Cornwall, was within a few years so beaten that Trevithick, in
his challenge to Woolf, offered to throw in the Watt engine as a
make-*weight, and with such odds to bet him two to one that his
comparatively small and cheap high-pressure engine should beat the two
big ones, both in power, in first cost, and in economical working. The
Watt engine was one of his largest, with a 72-inch cylinder. Its power
was equal to Trevithick's 33-inch pole-engine, when worked with steam
of 34 lbs. to the inch; but the latter also worked with three times
that pressure of steam, whereby its power was increased threefold. The
first cost of these engines was probably in inverse proportion to their
power. Trevithick's cost 700_l._, while three times that sum would not
pay for the Watt engine. The reported duty of Watt's Herland engine was
twenty-seven millions; and if the trial was with his ordinary bushel of
112 lbs. of coal, the duty would only be equal to twenty millions with
84 lbs. of coal, which constituted the Cornish bushel.

Trevithick's pole high-pressure steam-engine did fifty-seven millions;
in other words, performed the same work as the Watt engine with less
than half of the daily coal. This large economy led to orders for many
engines, on his promise that they should cost much less than those of
Watt of equal power, and should perform the work with one-third of
the coal. Some believed him, though others were stony-hearted, and as
obstinate as donkeys.

 [Rough draft.]

  "MR. PHILLIP,          "PENZANCE, _8th March, 1816_.

 "Sir,--I long since expected to have heard from you that my agreement
 with the Herland adventurers was executed. I have in every respect
 fulfilled my part of the engagement with the adventurers, and expect
 that they will do the same with me. The engine continues to work well.
 Every person that has seen it, except Joseph Price, A. Vivian, Woolf,
 and a few other such like beasts, agrees that it is by far the best
 engine ever erected. Its performance tells its effects, in spite of
 all false reports.

 "Joseph Price and A. Vivian reported that the engine was good for
 nothing, that it would not do four millions, and that at the next
 Tuesday meeting they would turn it idle. On the evening before the
 meeting they met at Camborne for that purpose.

 "Captain A. Vivian did not attend the meeting. I could not help at the
 meeting threatening to horsewhip J. Price for the falsehoods that he
 with the others had reported.

 "I hear that he is to go to London to meet the London committee on
 Monday. I hope the committee will consider J. Price's report as from
 a disappointed man. It is reported that he has bought very largely in
 Woolf's patent, which now is not worth a farthing, besides losing the
 making my castings, which galls him very sorely.

 "The water sinks regularly 20 fathoms per month, including every
 stoppage. On Monday next I expect they will be putting down the second
 lift. The water rises about 8 inches per hour when the engine is idle,
 and when at work will sink it again at the same rate, showing that the
 engine is equal to double the growing stream. When drawing from the
 pool the sinking is not much above 4 inches per hour, which shows that
 the water drains from a great distance from the country. The engine
 is going fourteen strokes per minute, 10-feet stroke, 14-1/2-inch
 box. When Herland worked last they drew a 14-inch box, 7-feet stroke,
 twelve strokes per minute in winter, and seven strokes per minute in
 summer. Therefore it appears that the winter water is about from seven
 to eight strokes per minute, and the summer water from four to five
 strokes per minute for this engine.

 "The engine has forked faster the last week than she did before. I
 think that the great quantity of water that was laying round the mine
 at the surface is nearly drawn down, and that as we get down to a
 closer ground the drainage will not be so much. If we have dry weather
 the water will, at the next shallow level, fall off two strokes per
 minute before the next lift is in fork. If it continues the same we
 can continue to sink 20 fathoms per month, exclusive of the time it
 will take to fix the lifts. As we get down the house of water will
 lessen considerably. The expense of the engine is about 100l. per
 month. The sumpmen and others attending on the forking the water,
 about 100_l._ per month more. They have all the materials on the mine
 for the pit-work, therefore a very trifling sum will bring the water
 down to the 60-fathom level, when the mine will pay her own expense.

 "I will thank you for an account of the meeting.

  "Your obedient servant,
  "R. TREVITHICK."

Mr. Phillip was the financial managing shareholder--more particularly
with the Londoners--at that resuscitation of Herland Mine; and though
the new engine was comparatively cheap, both in its first cost and in
its consumption of coal, and satisfactorily reduced the water in the
mine, payment for it was withheld because the currents of self-interest
were against Trevithick. Mr. Joseph Price was the manager of a
steam-engine manufactory at Neath Abbey, in South Wales, and had been
in the habit of supplying castings for Cornish mines. Arthur Woolf was
then striving to bring into use his patent double-cylinder engine, and
patent high-pressure steam-boiler, which Trevithick looked on as copies
from Hornblower and himself. This, added to Woolf's sarcastic manner of
speech, roused Trevithick's anger.

Putting aside the words of the disputants, the fact is stated that the
pole-engine, with a reduced steam pressure, worked a pump 14-1/2 inches
in diameter, 10-feet stroke, fourteen strokes per minute; while the
largest and best engine by Watt in Cornwall, placed on the same mine,
with a 72-inch steam-cylinder, gave motion to a pump of 14 inches in
diameter, 7-feet stroke, at twelve strokes a minute; being in round
numbers just one-half the amount of the work performed by Trevithick's
comparatively small engine, which had not a single feature of the Watt
engine in it.

 [Rough draft.]

  "CAPTAIN JOE ODGERS,       "PENZANCE, _March 7, 1816_.

 "Sir,--I have your favour of the 27th February, and requested Mr. Page
 to send to you a sketch of the agreement. On seeing him yesterday,
 I found that he had neglected to send it to you. He will leave the
 country for London in a few days, and intends to call on you at
 Dolley's as soon as he arrives. I do not know that the agreement
 matters much for a few days up or down. The terms are well understood
 between us, which is that the adventurers and I equally share the
 advantages that may arise from this new engine over Boulton and
 Watt's. When you have fully arranged with your adventurers about the
 engine, please to write me, and I will immediately proceed to order
 the engine; and in the interim the agreement will be drawn up by Mr.
 Page, and executed either here or in London, just as may suit.

  "I remain, &c.,
  "R. TREVITHICK.

 "P.S.--Herland engine goes on better and better. Your adventurers will
 get a satisfactory account by applying in town to Mr. Wm. Phillip,
 No. 2, George Yard, Lombard Street. He is the principal of the London
 adventurers."

Trevithick believed that mine adventurers would agree to pay him
one-half the saving caused by his engines, as compared with the
cost of fuel in the Watt engine. The duty performed by the latter
was understood and agreed to generally; persons were chosen by the
adventurers to experiment and report on the duty of Trevithick's
pole-engine, that the amount of payment might be ascertained in
proportion to the saving effected.

  "MR. GIDDY,             "PENZANCE, _April 2, 1816_.

 "Sir,--I have long wished to write to you about the Herland engine,
 but first wished to see the engine loaded with a second lift, and
 a trial made of the duty. Yesterday was fixed on, before ordering
 another engine for the eastern shaft.

 "The persons attended. The arbitrators gave the duty as forty-eight
 millions, and said they had no doubt the engine would perform above
 sixty millions before getting to the bottom of the mine.

 "They were much within the duty, but I did not contend with them, as
 they said it was quite duty enough.

 "The engine worked 9-1/4 strokes per minute, with 2 bushels of coal
 per hour for the whole time, 10-feet stroke. There were two pump-lifts
 of 14-1/2-inch bucket, making 43 fathoms, and 26 fathoms of 6-inch for
 house-water.

 "The steam was from 100 to 120 lbs. to the inch. The valve open while
 the plunger-pole ascended 20 inches, then went the remainder of the
 10-feet stroke expansive.

 "It went exceedingly smooth and regular. Some time since, by way of
 trying the power of the engine, we disengaged the balance-bob. The
 engine worked twenty strokes per minute, with 17 tons of rods, &c.,
 and drew 14-1/2-inch bucket 23-1/2 fathoms, and a 6-inch bucket 26
 fathoms, 10-feet stroke, twenty strokes per minute.

 "This was about 45,000 lbs. weight, with the speed of 200 feet per
 minute, which makes the duty performed more than the power of three
 72-inch cylinders, single, of Boulton and Watt, say of 8-feet stroke,
 10 lbs. to the inch, nine strokes per minute, which is more than these
 engines will perform. I have all the orders for every engine now
 required in the country, which is not to be wondered at, for one-tenth
 part of the expense in the erection will do, and the duty is not less
 than three times as much as other engines. This will be proved before
 we get to the bottom.

 "The engine now works at about two-fifths of the load which she will
 have when at the bottom. When the next lift is in fork I will write to
 you again.

  "I am, Sir, your humble servant,
  "RICHARD TREVITHICK."

Independent examiners reported that the Herland pole-engine did
forty-eight millions of duty, under various pressures of steam,
up to 120 lbs. to the inch, working five-sixths of the stroke
expansively, with a speed of twenty strokes a minute, or double the
speed of the Watt engine; and the importance of those facts deserves
the scrutiny and close study of youthful engineers. A small cheap
engine, of 33-inch cylinder, similar in general construction to the
Wheal Prosper pole-engine, but still more simple from the absence of
air-pump and condenser, did as much work as three of Watt's largest
engines with cylinders of 72 inches in diameter. This great stride
in the useful value of the steam-engine was forced on the public by
Trevithick's single-handed energy, when every man was against him,
even Henry Harvey, his brother-in-law and friend, his former partner,
Andrew Vivian, and his once carpenter and assistant, Arthur Woolf.
As a closing attempt to finally crush him, he was made personally
responsible for the payment of an engine erected for the benefit of
others. This was the great trial test of the power and economy of the
purely high-pressure expansive steam-engine as compared with the Watt
low-pressure vacuum engine applied to large pumps.

  "SIR,        "HAYLE FOUNDRY, _18th April, 1816_.

 "I was at Herland to-day. Captain Grose received a letter while I was
 there, signed by Captain William Davey and Joseph Vivian, requesting
 him to appoint others to attend the trial of the engine, as it would
 not be convenient for them to do it.

 "Captain Samuel Grose, jun., brought down the drawing for your engine.
 He said he had taken off the working gear only. If you would wish it,
 we will make the working-gear and all the wrought-iron work on the
 drawing for the two engines ordered, and will take on a man or two
 immediately for that purpose. You will let me know about this before
 you set off, and also if any alteration is to be made in the beam for
 Wheal Treasure engine, since you have altered the size of the pole. We
 had cast the case, but I suppose it will suit some place else.

  "Your obedient servant,
  "HENRY HARVEY.

 "MR. RICHARD TREVITHICK."

 "About 1815 or 1816 I was employed by Captain Trevithick to erect
 various pole-engines, one of them at Saltram Stream. It had worked
 at Tavistock; it was a horizontal high-pressure pole puffer. Captain
 Samuel Grose was then erecting for Captain Trevithick a 24-inch
 high-pressure pole-engine at Beeralstone, on the Tamar, to drain a
 lead mine. I assisted Captain Grose. The stroke was about 8 feet. It
 worked with cross-head and side rods. There were two wrought-iron
 boilers about 3 feet 6 inches in diameter and 40 feet long. The fire
 and flues were outside. The steam pressure, 60 lbs. to the inch. I
 also erected a similar engine with a 20-inch pole at Wheal Treasure,
 now called Fowey Consols Mine; and one at Logassack, near Padstow.
 Those two had brass poles. It was found that the poles cut and wore
 in their passage through the stuffing box, the middle wearing more
 than the ends, causing steam to escape. A similar pole of Captain
 Trevithick's erecting was then working at Wheal Regent, near St.
 Austell.

 "In 1818 I saw working at Wheal Chance Mine, near Scorrier, an old
 60-inch cylinder Boulton and Watt engine. A pole of Trevithick's
 was fixed between the cylinder and the centre of the main beam.
 High-pressure steam was first worked under the pole and then expanded
 in the cylinder."[35]

[Footnote 35: Recollections of Captain H. A. Artha, Penzance, 1870.]

The late Mr. William Burral, for many years manager of the
boiler-making department at Messrs. Harvey and Co., at Hayle, said:--

 "About the year 1815 or 1816 I helped to erect at Treskerby Mine an
 engine for Captain Trevithick. Mr. Sims was the engineer of the mine.
 The engine had the usual cylinder, and close to it one of Captain
 Trevithick's poles was fixed. The boilers were Captain Trevithick's
 high-pressure. The steam was first turned on under the pole. When she
 had finished her up-stroke the steam passed from under the pole on to
 the top of the piston in the cylinder. There was a vacuum under the
 piston. The steam-cylinder was 58 inches in diameter, about 9 or 10
 feet stroke. The pole was 36 inches in diameter, and a less stroke
 than the piston, because it was fixed inside the cylinder, nearer to
 the centre of the beam. There was a pole-engine then working at Wheal
 Lushington, also at Poldice, and at Wheal Damsel."

 "Captain Artha recollects at Wheal Alfred Mine in 1812 the 66-inch
 cylinder pumping engine used a pole air-pump; one or two whim-engines
 on the same mine also used them. Wheal Concord pumping engine, in 1827
 had a similar air-pump. Old Wheal Damsel, near Treloweth, used one as
 late as 1865. The condensing water and air passed through a branch
 with a valve on it near the top of the pole-case, just under the
 stuffing box There was a foot-valve at the bottom of the pole-case."[36]

[Footnote 36: Captain Artha became the resident engineer at the Real del
Monte mines in Mexico; Captain Samuel Grose, one of the first Cornish
mine engineers; and Mr. Burral, the engineer of a department at the
engine-works of Messrs. Harvey and Co.]

The writer has had the pleasure of personal acquaintance with each of
those three gentlemen, who as young engineers commenced their labours
in the erection of Trevithick's engines.

No sooner had Trevithick perfected the pole condensing engine and
then the pole puffer-engine, than he, in conjunction with Sims, who
had just taken part in the erection of one of his high-pressure steam
pole-engines for working the pumps at Beeralstone Mine, combined the
pole with the ordinary Watt vacuum engines, supplying them with steam
from his high-pressure boilers, in other words, converting them from
their original form of low-pressure vacuum engines to high-pressure
expansive compound steam-engines.

The old 60-inch cylinder Boulton and Watt engine, at Wheal Chance
(one of Watt's favourite engines), was in 1818 transformed into a
high-pressure engine, with Trevithick's pole placed between the centre
of the main beam and the steam-cylinder. The high-pressure steam from
Trevithick's new boilers was turned under the pole for the up-stroke,
after which it was expanded in the old and much larger cylinder on the
top of the piston causing the down-stroke; it then, by its passage
through the equilibrium valve, allowed the piston in the large cylinder
to make its up-stroke, by equalizing the pressure of steam on its
top and bottom, while a fresh supply of strong steam from the boiler
admitted under the pole gave power to the up-stroke; and finally, the
comparatively low-pressure steam under the large piston passed to the
condenser and air-pump to form a vacuum for the down-stroke, as in the
Watt engine.

Sims, the engineer at Wheal Chance, one of the mines in the eastern or
Watt district, was converted and became in 1815 or 1816 a partner with
Trevithick, and erected, at Treskerby Mine, Trevithick's high-pressure
pole of 36 inches in diameter, as an addition to the old Watt engine
working with a cylinder 58 inches in diameter.

Watt, then, within a year or two of his death, was too old to any
longer take part in the contest; his engine in the hands of others was
converted and became a high-pressure expansive engine.

Trevithick, as a further proof that he could do without the Watt patent
air-pump bucket, with its piston and valves, removed it from a Watt
engine at Wheal Alfred Mine in 1812, replacing it by one of his poles,
answering the same purpose, but different in construction. Many other
mines used them; one remained at work in Old Wheal Damsel in 1860. They
have also been used in steamboat air-pumps.

Having traced during a period of five or six years the rise and
progress of the high-pressure expansive pole condensing-engines, the
high-pressure expansive pole puffer-engine, and the combined pole and
cylinder high-pressure engine, their value in a commercial sense may
be further tested by the public acts of the time. Lean, an authority
on such matters, and certainly not given to unduly praise Trevithick,
spoke as follows on the duty of those particular engines at various
periods; and not the least noteworthy is the fact, that Herland,
Poldice, and Treskerby, that were prominent in the early use of the
Watt engine, threw off their allegiance but shortly before the last
days of the great engineer, and converted his low-pressure steam vacuum
engines into Trevithick high-pressures.

 "In 1798 Messrs. Boulton and Watt, who on a visit to Cornwall, came
 to see it--'the Herland engine'--and had many experiments tried to
 ascertain its duty; it was under the care of Mr. Murdoch, their agent
 in the county. Captain John Davey, the manager of the mine, used to
 state that it usually did twenty millions, and that Mr. Watt, at
 the time he inspected it, pronounced it perfect, and that further
 improvement could not be expected.

 "In 1811 the average duty of the three engines (Boulton and Watt's)
 on Wheal Alfred Mine was about twenty millions. These engines were at
 that time reckoned the best in the county.

 "In 1816 Sims erected an engine at Wheal Chance, to which he applied
 the pole adopted by Trevithick in his high-pressure engine. This
 engine attained to forty-five millions; and in 1817 it did 46·9
 millions.

 "In 1814 Treskerby engine is reported as doing 17·48 millions.--Wm.
 Sims, engineer.

 "In 1820 Treskerby engine, to which Trevithick's high-pressure pole
 had been adapted, had reached 40·3 millions."[37]

[Footnote 37: Lean's 'Historical Account of the Steam-Engine in
Cornwall,' pp. 11, 32, 36.]

The Herland engine of Watt in 1798 did twenty millions; in 1816
Trevithick's high-pressure pole puffer in the same mine did forty-eight
millions. In 1820 his high-pressure pole-engine was combined with a
Watt low-pressure engine, thereby more than doubling its economical
duty.

In 1813 Trevithick wrote:--

 "That new engine you saw near the sea-side with me (Wheal Prosper
 high-pressure pole condensing engine) is now lifting forty millions
 one foot high, with a bushel of coal, which is nearly double the duty
 that is done by any other engine in the county. A few days since I
 altered a 60-inch cylinder engine at Wheal Alfred to the same plan,
 and I think she will do equally as much duty. I have a notice to
 attend a mine meeting, to erect a new engine equal in power to a
 63-inch cylinder single."[38]

[Footnote 38: See Trevithick's letter, January, 1813, vol. ii., p. 55.]

In the four or five years from his return to Cornwall in 1810, to his
leaving for South America in 1816, he doubled the duty and the power of
the steam-engine. Watt once said he had received an oblique look from
Trevithick, sen. The time was now come for Trevithick, jun., to return
the compliment; his improved engines having made their way into the
eastern mine district, which Watt once looked upon as his own.

Trevithick was short of money and on the point of leaving England for
South America, when Mr. Sims, in the employ of Messrs. Williams and
Co., favourable to low pressure, was sent to negotiate for the purchase
of a share in Trevithick's patent of 1815 for the high-pressure steam
expansive pole-engine.

 "18th October, 1816.--Agreement between Trevithick and Mr. William
 Sims, prepared by myself and Mr. Day, solicitor for Mr. Sims, or
 for Mr. Michael Williams, under whom Sims acted, recites, that in
 consideration of 200_l._ paid by Sims, he was to have a moiety of the
 patent for Cornwall and Devon, and that I should have power to act and
 make contracts whilst Trevithick was out of England.

 "The day after contract signed, Trevithick sailed in the 'Asp,'
 Captain Kenny, for South America. I was on board when the ship sailed.

 "I see among my papers, in May, 1819, in reference to the patent, is
 the following note:--'Mr. Michael Williams said it was verbally agreed
 that Captain Trevithick should have one-quarter part of the savings
 above twenty-six millions.' This, I believe, was the average duty of
 the engines at that time.

 "I had several assurances relative to Trevithick's claims, and much
 correspondence, but no allowance was made from any mines but Treskerby
 and Wheal Chance; though Trevithick's patent and boilers were used
 throughout the county without acknowledgment; and the duty of the
 engines had soon increased from twenty-six millions to about seventy
 millions.

 "In 1819 I attended at the account-houses of Treskerby and Wheal
 Chance, of which the late Mr. John Williams, of Scorrier, was the
 manager, in consequence of some of the adventurers objecting to
 continue the allowances on the savings to Captain Trevithick, when Mr.
 Williams warmly observed, that whatever other mines might do, he would
 insist, as long as he was manager for Treskerby and Wheal Chance, the
 agreement made should be carried into effect.

  "I remain, my dear Thomas,
  "Your very affectionate father,
  "RD. EDMONDS."[39]

[Footnote 39: Portion of a letter written at Penzance, 8th February,
1853.]

The agreement with Mr. Sims, or rather with Mr. Michael Williams, late
M.P. for Cornwall, who exercised large authority in Cornish mines,
was that he should have for 200_l._ one-half of the patent for the
high-pressure pole-engine, as applied to Cornwall and Devon.

Trevithick had desisted from securing a patent for the large
high-pressure steam-boilers and expansive working, on a verbal
understanding that he should receive one quarter of the saving from
the reduced consumption of coal by those two particular inventions,
twenty-six millions of pounds of water raised one foot high by a bushel
of coal of 84 lbs., being the duty of the best Watt engines, to be
taken as a starting-point for the payment. Treskerby and Wheal Chance
paid for the pole-engine, but the Trevithick boilers suitable for high
steam, and the simple methods of working it expansively, had been made
so generally public, that people professed to think they had a right to
them, when but a few years before they had thrown the inventor off his
guard by saying "everybody knows that the Cornish boiler is your plan,
and as it cannot be denied, a patent will be of no service."

Mr. John Williams[40] stated "that whatever other mines might do, he
would insist, as long as he was manager for Treskerby and Wheal Chance,
the agreement made should be carried into effect." The Williamses paid
to Trevithick 300_l._ for the saving of coal by the pole patent engine,
as an "acknowledgment of the benefits received by us in our mines;"
but no payment was made for the greater invention of the high-pressure
steam-boilers then in general use.

[Footnote 40: Mr. John Williams had the remarkable dream, many hours
before the event, enabling him to describe the particulars of the
assassination of Perceval in 1812.]

In 1814 the Watt Treskerby engine did seventeen and a half millions.
Trevithick's boiler and pole were applied, and the duty was increased
to more than forty millions. In 1816 the same changes were made in
Wheal Chance, and the duty rose to more than forty-six millions. The
consumption of coal was reduced to one-half, amounting in round numbers
to a gain of 500_l._ a month in those two mines alone. /#

  "TREVINCE, near TRURO,

  "DEAR SIR,                 _5th January, 1853_.

"I am favoured with your letter of the 31st ult., enclosing also one
from Mr. F. Trevithick, of the 24th idem, and have much pleasure in
complying with your joint request to the best of my ability. I was
well acquainted with the late Mr. Rd. Trevithick, having had frequent
occasion to meet him on business and to consult him professionally; and
I am gratified in having the present opportunity of bearing testimony
to his distinguished abilities, and to the high estimation in which the
first Cornish engineers of the day then regarded him. I need scarcely
say that time has not lessened the desire in this county especially to
do him justice. As a man of inventive mechanical genius, few, if any,
have surpassed him, and Cornwall may well be proud of so illustrious a
son.

"At this distance of time I can scarcely speak with sufficient
exactness for your purpose of the numerous ingenious and valuable
mechanical contrivances for which we are indebted to him, but in
reference to his great improvements in the steam-engine I have a
more particular recollection, and can confidently affirm that he was
the first to introduce the high-pressure principle of working, thus
establishing a way to the present high state of efficiency of the
steam-engine, and forming a new era in the history of steam-power. To
the use of high-pressure steam, in conjunction with the cylindrical
boiler, also invented by Mr. Trevithick, I have no hesitation in saying
that the greatly-increased duty of our Cornish pumping engines, since
the time of Watt, is mainly owing; and when it is recollected that
the working power now attained amounts to double or treble that of
the old Boulton and Watt engine, it will be at once seen that it is
impossible to over-estimate the benefit conferred, either directly or
indirectly, by the late Mr. Trevithick, on the mines of this county.
The cylindrical boiler above referred to effected a saving of at least
one-third in the quantity of coal previously required; and in the year
1812 I remember our house at Scorrier paying Mr. Trevithick the sum
of 300_l._ as an acknowledgment of the benefits received by us in our
mines from this source alone. Mr. Trevithick's subsequent absence from
the county, and perhaps a certain degree of laxity on his own part in
the legal establishment and prosecution of his claims, deprived him of
much of the pecuniary advantage to which his labours and inventions
justly entitled him; and I have often expressed my opinion that he was
at the same time the greatest and the worst-used man in the county.

"Amongst the minor improvements introduced by him, it occurs to me to
notice that he was the first to apply an outer casing to the cylinder,
and by this means prevent, still further than Watt had succeeded in
doing, the loss of heat by radiation.

"As connected with one of the most interesting of my recollections of
Mr. Trevithick, I must mention that I was present by invitation at
the first trial of his locomotive engine, intended to run upon common
roads, and of course equally applicable to train and railways. This
was, I think, about the year 1803, and the locomotive then exhibited
was the very first worked by steam-power ever constructed.

"The great merit of establishing the practicability of so important
an application of steam, and the superiority of the high-pressure
engine for this purpose, will perhaps more than any other circumstance
serve to do honour through all times to the name of Trevithick. The
experiment which was made on the public road close by Camborne was
perfectly successful; and although many improvements in the details
of such description of engines have been since effected, the leading
principles of construction and arrangements are continued, I believe,
with little alteration, in the magnificent railroad-engines of the
present day. Of his stamping engine for breaking down the black rock in
the Thames, his river-clearing or dredging machine, and his extensive
draining operations in Holland, I can only speak in general terms,
that they were eminently successful, and displayed, it was considered,
the highest constructive and engineering skill. As a man of enlarged
views and great inventive genius, abounding in practical ideas of the
greatest utility, and communicating them freely to others, he could
not fail of imparting a valuable impulse to the age in which he lived;
and it would be scarcely doing him justice to limit his claims as a
public benefactor to the inventions now clearly traceable to him,
important and numerous as these are. From my own impressions I may say
that no one could be in his presence without being struck with the
originality and richness of his mind, and without deriving benefit
from his suggestive conversation. His exploits and adventures in South
America, in connection with the Earl of Dundonald, then Lord Cochrane,
will form an interesting episode in his career; and altogether, I am of
opinion that the Biography which you have undertaken will prove highly
interesting and valuable, and I wish you every success in carrying it
out.

  "Believe me, my dear Sir,
  "Yours very faithfully,
  "MICHAEL WILLIAMS.

  "E. WATKIN, Esq.,
  "_London and North-Western Railway_,
  "_Euston Station, London_."

Arthur Woolf shortly after that time (1811) erected his double-cylinder
engines in Cornwall. The late Captain Samuel Grose, when giving the
writer his recollections of Trevithick, said:--

 "When he returned from London to Cornwall, about 1810 or 1811,
 he employed me to look after the erection of the Wheal Prosper
 high-pressure engine. Oats, Captain Trevithick's head boiler-maker,
 was constructing the boilers; Woolf came into the yard, and examined
 them. 'What do'st thee want here?' asked Oats. 'D--n thee, I'll soon
 make boilers that shall turn thee out of a job!' was Woolf's reply.
 He was a roughish man. When his brother Henry mutinied at the Nore,
 Woolf, who was then working an engine in Meux's brewery, and had
 married the lady's maid, made interest with his employer to save Henry
 from being hanged at the yard-arm, and afterwards found employ for him
 in Cornwall. He was but a clumsy mechanic. Woolf used to blow him up
 by saying, 'D--n thee, I wish I'd left thee to be hanged.'"

The writer, who knew Oats, has heard him tell similar stories of the
rival engineers.

In 1800, Woolf, who had been a mine carpenter, went to London with
the first high-pressure steam-engine which Trevithick had sent beyond
the limits of Cornwall[41]--probably to Meux's brewery,[42] for he was
there in 1803, and in the receipt of 30_l._ a year from Trevithick as
engine-fireman. From the date of Woolf's patent in 1804, his pay from
Trevithick ceased, and with it their friendship. Trevithick used to
say, "Woolf is a shabby fellow."

[Footnote 41: See Trevithick's account-book, vol. i., p. 90.]

[Footnote 42: Captain John Vivian's recollections, vol. i., p. 142.]

Patents sprang up like mushrooms after Trevithick had so liberally
cast forth the seeds of the high-pressure engine, making the security,
or even the form of a patent, a doubtful matter. The perfecting of
expansive high-pressure engines was like the boiler, the result of
years of trial. When matured in 1816 it saved Cornwall and the world
one-half of the coal that before had been consumed in low-pressure
steam-engines. Every engineer became, more or less, an expansive
worker, and Trevithick's saving of hundreds of thousands of pounds
annually to the general public, gave to him little or no reward.

At the period of those high-pressure pole-engine experiments,
Trevithick had devoted twenty years of constant labour to the
improvement and extended use of the steam-engine, causing it to
assume every variety of form except that of the Watt patent engine,
an approach to which was unusual, as evidenced in the high-pressure
steam Kensington model of 1796, without beam, parallel motion,
air-pump, or condenser, having no one portion either in principle or
detail similar to the Watt engine, being portable and not requiring
condensing water, with single and double cylinders, placed vertically
or horizontally. Having during twelve busy years constructed over a
hundred high-pressure steam-engines, scarcely any two of which were
exactly alike, he departed if possible still further from the Watt
type, and went back apparently, though not in reality, to the Newcomen
engine, simplifying it by the omission of the great bob, and use of
condensing water, as in the nautical labourer and steamboat engine
of about 1810,[43] and the South American mine engines of 1816,[44]
which had open-top cylinders, more like a Newcomen than a Watt, but
if possible even more simple and primitive-looking than the former.
Again, compare the thrashing engine of 1812[45] with the Newcomen of
1712:[46] the great and all-important difference being that one was
a high-pressure steam-engine, the other a low-pressure atmospheric
engine. Then came the varieties of high-pressure steam pole-engines,
working very expansively either as puffers or condensers, retaining the
same dissimilarity to the Watt engine: and lastly, the combination of
the high-pressure pole with the Watt patent engine, thereby causing the
old Watt engine to do more than double the work it had done when new
from the hands of the maker, and also to perform this increase of work
with a decrease in the consumption of coal.

[Footnote 43: See vol. i., p. 336.]

[Footnote 44: See chap. xxi.]

[Footnote 45: Vol. ii., p. 37.]

[Footnote 46: Vol. i., p. 5.]

The following chapter will trace the adaptation of high-pressure
expansive steam, from cylindrical boilers, to the form of pumping
engine still in general use.




CHAPTER XX.

THE WATT AND THE TREVITHICK ENGINES AT DOLCOATH.


Having up to 1816 traced the progress of the steam-engine in Cornwall
through a century, during the latter half of which Trevithick, sen.,
and his son were among its most prominent improvers, the latter
having devoted a quarter of a century to the work, the effect of
which is shown in the skeleton outlines of a few classes of engines,
one important feature still remains for examination before a correct
judgment can be formed of the events of this period and their prime
movers.

The use of an increasing pressure of steam gave increased force and
value to the improved steam-engine, but the power of constructing
engines and boilers to render the increased pressure manageable was the
result of a lifetime of labour.

Savery, whose engine was scarcely more than a steam-boiler, failed
to control its force, and is said to have blown the roof from over
his head. The mechanism of Newcomen's engine was well arranged, but
suitable only for the working of pumps, and its power was limited to
the weight of the atmosphere, from which it was called the atmospheric
engine.

In 1756, an atmospheric engine with a cylinder of 70 inches in diameter
worked at the Herland Mine, "the only objection to which was the cost
of the coal, to lessen which several methods had been suggested for
increasing the elasticity of the steam, and reducing the size of the
boiler."[47]

[Footnote 47: Borlase's 'Natural History of Cornwall.']

In 1775 Richard Trevithick, sen., removed the flat top of a Newcomen
boiler, and substituted a semicircular top, enabling it to contain
stronger steam, and at the same time he improved the mechanical part
of the engine by finding a better resting-place for the steam-cylinder
than the top of the large boiler. Pryce gives a drawing of this engine
as the best at that time in Cornwall.[48]

[Footnote 48: See drawing, vol. i., p. 25.]

 "It is known as a fact that every engine of magnitude consumes
 3000_l._ worth of coal every year.

 "The fire-place has been diminished and enlarged again. The flame
 has been carried round from the bottom of the boiler in a spiral
 direction, and conveyed through the body of the water in a tube (one,
 two, or three) before its arrival at the chimney.

 "Some have used a double boiler, so that fire might act on every
 possible point of contact, and some have built a moorstone boiler,
 heated by three tubes of flame passing through it.

 "A judicious engineer does not attempt to load his engine with a
 column of water heavier than 7 lbs. on each square inch of the
 piston."[49]

[Footnote 49: See Pryce's 'Mineralogia Cornubiensis,' published 1778.
Appendix.]

While Pryce's book was being printed, Watt in 1777 wrote of the Cornish
steam-engines:--

 "I have seen five of Bonze's engines, but was far from seeing the
 wonders promised. They were 60, 63, and 70 inch cylinders at Dolcoath
 and Wheal Chance. They are said to use each about 130 bushels of coals
 in the twenty-four hours, and to make about six or seven strokes per
 minute, the stroke being under 6 feet each. They are burdened to 6,
 6-1/2, and 7 lbs. per inch."[50]

[Footnote 50: Smiles' 'Lives of Boulton and Watt.']

The 63-inch was an open-top cylinder atmospheric engine at Dolcoath
Mine under the management of Trevithick, sen.; and shortly after, in
1777 or 1778, Watt's first engine was erected in Cornwall.[51]

[Footnote 51: See vol. i., p. 30.]

In 1783 Trevithick, sen., gave Watt an order for a patent engine for
Dolcoath, in size similar to the old Newcomen atmospheric, having a
cylinder 63 inches in diameter, that a working trial might be made
between the rival engines. The Watt engine having a cylinder-cover,
with the patent air-pump and condenser, was known in the county as the
Dolcoath great 63-inch double-acting engine. Three steam-engines were
then at work in that mine: Trevithick senior's Carloose (then called
Bullan Garden) atmospheric 45-inch cylinder, the atmospheric 63-inch
cylinder, and Watt's 63-inch cylinder double-acting vacuum engine; all
of which continued in operation side by side for five years until 1788,
when for a time Dolcoath ceased to be an active mine. Trevithick, jun.,
was then a boy of seventeen years.

After ten years of idleness and rust, as if mourning the death of
Trevithick, sen., in 1798 Richard Trevithick, jun., as engineer, and
Andrew Vivian as manager, induced shareholders to resuscitate the old
mine. Fire was again given to the voracious jaws of the boilers, and
the three engines recommenced their labours and their rivalries.

A year or two before this Trevithick had made models of high-pressure
steam-engines. Davies Gilbert, in 1796, met him among other engineers,
giving evidence in the Watt lawsuits, when he mentioned his ideas of
an engine to be worked solely by the force of steam. Watt had claimed
such an engine in his patent twenty-seven years before, but had failed
to carry it into practice. Hornblower had tried something like it in
his double-cylinder expansion engine, but he did not use high-pressure
steam, and consequently also failed.

The _idea_, therefore, of expansive steam was not new, but the _useful
mastery_ of it was. Savery had tried expansive steam before Watt
patented it; the latter went to law with Hornblower for an infringement
of the _idea_, when neither of them had in truth constructed an
expansive steam-engine. The low pressure of the steam from the boilers
used by Hornblower and Watt did not admit of profitable expansion
in the cylinder; at its full boiler pressure it constituted but a
comparatively small portion of the power of the engine: to reduce that
power by expansion was as apt to be a loss as a gain. The steam-engine
was still dependent for its power mainly on steam as an agent for
causing the required vacuum, until 1796, when Trevithick disclosed his
method of constructing small cylindrical boilers and engines suitable
for giving power from the strong pressure of the steam, irrespective of
vacuum.

Lean, who favoured Watt rather than Trevithick, thus records the advent
of Watt's expansive engine:--

 "In 1779 to 1788 Mr. Watt introduced the improvement of working steam
 expansively, and he calculated that engines which would previously do
 nineteen to twenty millions would thus perform twenty-six millions;
 but I do not find any record of this duty being performed in practice.
 In 1785 Boulton and Watt had engines in Cornwall working expansively,
 as at Wheal Gons and Wheal Chance in Camborne; but in these the steam
 was not raised higher than before, and the piston made a considerable
 part of the stroke therefore before the steam-valve was closed.

 "In 1798, on account of a suit respecting their patent, which was
 carrying on by Boulton and Watt, an account of the duty of all the
 engines in Cornwall was taken by Davies Gilbert, Esq., and the late
 Captain Jenkin, of Treworgie, and they found the average to be about
 seventeen millions."[52]

[Footnote 52: Lean's 'Historical Statement of Steam-Engines in
Cornwall,' p. 7.]

One of these so-called expansive Watt engines, erected at Wheal Chance,
was converted into a real expansive engine by Trevithick, as described
in the foregoing chapter, by his high-pressure steam-boilers and the
addition of his pole-engine. The conversion of the other, a 63-inch
low-pressure vacuum engine at Wheal Gons, will be traced in this
chapter.

Mr. Taylor, who for many years took an active interest in Cornish
mining, says:--

 "In 1798 an engine at Herland was found to be the best in the county,
 and was doing twenty-seven millions, but being so much above all
 others, some error was apprehended. This engine was probably the best
 then ever erected, and attracted therefore the particular attention of
 Messrs. Boulton and Watt, who, on a visit to Cornwall, came to see it,
 and had many experiments tried to ascertain its duty. It was under the
 care of Mr. Murdoch, their agent in the county.

 "Captain John Davey, the manager of the mine, used to state that
 it usually did twenty millions, and that Mr. Watt, at the time he
 inspected it, pronounced it perfect, and that further improvement
 could not be expected."[53]

[Footnote 53: 'Records of Mining,' by John Taylor, F.R.S., &c., part i.,
p. 155; published 1829.]

This best engine from the hands of Watt and Murdoch in the Herland Mine
in 1798 may be taken as a Watt stand-point, when its usual duty was
twenty millions; and Trevithick and Bull erected a competing engine,
probably with an increased steam pressure, for Trevithick's portable
high-pressure engines were at that time coming into notice;[54] but no
trace remains of the result of this contest of the Watt and the Bull
engine, though it was one of the causes of the lawsuits.

[Footnote 54: See vol. i., p. 95.]

 "In 1799 Henry Clark worked as a rivet boy in Dolcoath, and carried
 rivets to construct Captain Trevithick's new boiler, said to be the
 first of the kind ever made. It looked like a great globe about 20
 feet in diameter, the bottom hollowed up like the bottom of a bottle;
 under this the fire was placed: a copper tube attached to this bottom
 went around the inside of the boiler, and then passed out through the
 side of the boiler, the outside brick flues then carrying the heat
 around the outside of the boiler and into the chimney.

 "Captain Trevithick's first plunger-pole lifts in Dolcoath were put in
 at this time and worked by this engine. Glanville, the mine carpenter,
 was head man over the engines when Captain Trevithick was away."[55]

 [Footnote 55: Henry Clark's recollections in 1869.]

 "Charles Swaine worked as a rivet boy in making Captain Trevithick's
 cylindrical wrought-iron boilers for the Dolcoath engine. Several
 of Captain Trevithick's high-pressure boilers were working in the
 mines before that, but not made exactly like the Dolcoath engine
 boilers. When I was a boy about the year 1804, several years before
 I worked on the Dolcoath engine boilers, I carried father's dinner
 to the Dolcoath smiths' shop, where he worked, and used to stop
 and watch the wood beam going up and down of Captain Dick's first
 high-pressure steam-whim. She was not a puffer, but a puffer-whim
 worked near by, called the Valley puffer. At that time most of Captain
 Dick's high-pressure boilers were smallish, cast iron outside, and
 wrought-iron tube."[56]

[Footnote 56: Working in the Valley smiths' shop, in Dolcoath Mine, in
1869.]

In 1799, shortly after the reopening of Dolcoath Mine, Trevithick,
jun., selected his father's second-hand atmospheric engine of 1775,[57]
to further improve it by a new boiler of uniformly globular figure,
with concave circular bottom, under which fire was placed; it was of
wrought iron, 24 feet in diameter, surrounded by external brick flues;
a large copper tube, starting from the boiler bottom, immediately
over the fire, served as an internal flue, carrying the fire by a
sweep around the interior in the water space, and then out through the
side of the boiler into the external brick flue. It may be said that
there was nothing new in a circular form of boiler, or in an internal
tube; but it will be admitted that this repaired engine, in this its
third stride in the march of advancement, made publicly known those
principles which in a few years more than doubled the power, the
economy, and the applicability of the steam-engine. His patent drawing
of 1802 shows this form of boiler applied to a small portable engine,
in which, for the sake of simplicity of structure and cheapness, cast
iron was used instead of wrought iron, and the internal tube omitted.[58]

[Footnote 57: See vol. i., p. 25.]

[Footnote 58: See vol. i., p. 128.]

The full detail estimate, from which the following items are extracted,
of the cost of alteration was written by Trevithick, jun., in the book
and on the page adjoining that containing the account of the former
alteration and re-erection of the same engine by Trevithick, sen., in
1775.

 "A 45-inch cylinder engine, working 20 lbs. to the inch:--

                                                           £  _s._ _d._
  Boilers, 8 tons at 42_l._                                 336  0 0
  Iron about ditto, 6 cwt. at 42_l._                         12 12 0
  Castings about ditto, 15 cwt. at 42_s._                    18  0 0
  Safety-valve and cocks                                      1  0 0
  Wood about bob, 200 ft. at 6_s._                           60  0 0
  Cast iron about ditto, 45 cwt. at 25_s._                   56  5 0
  Brass about ditto, 60 lbs. at 2_s._                         6  0 0
  Piston-rod, 4 in., 14 ft. long, 550 lbs. at 1_s._          27 10 0
  T-piece, 10 cwt. at 25_s._                                 12 10 0
  Cover, and bottom, and piston, 35 cwt. at 32_s._           56  0 0
  Nozzles, 6 cwt. at 32_s._                                   9 12 0
  Steam and perpendicular pipe, 10 cwt. at 25_s._            12 10 0
  Receiver, 2 ft. 4 in. long, and bottom, 15 cwt. at 25_s._  18 15 0
  Air-pump, bottom, and case, 10 cwt. at 25_s._              12 10 0
  Plunger, 22 in., 6 ft. long, 12 cwt. at 40_s._             24  0 0
  Force lift                                                  5  0 0
  Engineer                                                   66  0 0"

The term "single" refers to its open-top cylinder as originally erected
by Newcomen, when it was called the Carloose engine, and so it remained
after its re-erection in 1775, under the name Dolcoath new engine,
alias Bullan Garden; but after the last re-erection in 1799 it had a
cylinder-cover, and was called the Shammal 45-inch engine; "working 20
lbs. to the inch" meant the force on each inch of the piston, including
vacuum on the one side of 14 lbs. and steam on the other side of 6 lbs.
to the inch.

Watt, on his first visit to Cornwall, in 1777, spoke disparagingly of
the Newcomen atmospheric engines "burdened to 6 or 7 lbs. net to the
inch." Fifty years later Stuart described Watt's engine as "using steam
of a somewhat higher temperature than 212 degrees, so as to produce a
pressure between 17 and 18 lbs. on each square inch of the piston; yet
in practice, from imperfect vacuum and friction, it cannot raise more
water per inch than would weigh about 8-1/2 lbs.,"[59] or an increase of
net force--when compared with the Newcomen atmospheric--of only a pound
or two on the inch in the lapse of years embracing the active lifetime
of Watt. The cause of this slight increase of power is so simple that
it has been passed by unnoticed by very many. The steam pressure in
the Newcomen atmospheric was continued unaltered in the Watt vacuum
engine. Trevithick constructed the first boiler and engine capable of
safely and economically using the power of high-pressure steam. Nelson
was obliged to come to close quarters, that his shot, propelled by
weak cannon and low-pressure powder, might penetrate wooden ships. We
now manufacture and control high-pressure powder, so that 12 inches
of iron armour-plates cannot resist its force; but this knowledge
has taken nearly as long in growing to perfection as did the mastery
of high-pressure steam, and its use in the much more complicated
steam-engine.

[Footnote 59: Stuart's 'History of the Steam-Engine,' published 1824.]

Watt's engine, as described a quarter of a century after the expiration
of his patent and the advent of the high-pressure steam-engine, still
derived its gross force from 14 lbs. of vacuum and 2 or 3 lbs. of
steam, resulting in a net force of 8-1/2 lbs. Trevithick's engine of
1799, which heralded the last hours of the Watt patent authority,
and may be taken as the first distinct evidence of comparatively
high-pressure steam in large Cornish pumping engines, derived its power
from 14 lbs. of vacuum and 6 lbs. of steam, being together but 2 or 3
lbs. on the inch more than the Watt engine, but its net force of 12
lbs. to the inch was half again as much as the net force of the Watt
engine, the increase being wholly from the steam pressure, which was
never practised by Watt, and which in its almost unlimited force gives
the greatly increased power to modern steam-engines.

Trevithick's estimate for a new engine of the same size as the old
was 2000_l._, but as the old one could be improved for 1300_l._, the
latter course was adopted, the wooden main beam with its segment head
was retained, a cover was added to the cylinder, and a new piston-rod
and piston; a pole air-pump was used in lieu of the more usual Watt
air-pump bucket; a feed-pole forced water into the boiler,--an indirect
proof of increased steam pressure. The new globular boiler with
internal tube weighed 8 tons; the engineer's charge for carrying out
the work was 66_l._

The use of strong steam as the prime mover of the steam-engine
increased more rapidly beyond than within the limits of Cornwall, for
in 1802 was erected at Coalbrookdale a high-pressure steam-puffer
engine, to which Trevithick attached a pump which forced water through
a column of upright pipes, that the power of the engine might be
accurately measured. It worked with steam of from 50 to 145 lbs. on the
inch, and wholly discarded the vacuum which had been Watt's mainstay.

 "The boiler is 4 feet diameter, the cylinder 7 inches diameter, 3-feet
 stroke. The water-piston is 10 inches in diameter, drawing and forcing
 35 feet perpendicular, equal beam. I first set it off with about 50
 lbs. on the inch pressure against the steam-valve, for the inspection
 of the engineers about this neighbourhood. The steam continued to rise
 the whole of the time it worked; it went from 50 to 145 lbs. to the
 inch.

 "The engineers at this place all said that it was impossible for so
 small a cylinder to lift water to the top of the pumps, and degraded
 the principle, though at the same time they spoke highly in favour of
 the simple and well-contrived engine.

 "After they had seen the water at the pump-head, they said that it was
 possible, but that the boiler would not maintain its steam at that
 pressure for five minutes; but after a short time they went off, with
 a solid countenance and a silent tongue."[60]

[Footnote 60: See Trevithick's letter, August 22nd, 1802, vol. i., p.
153.]

This high-pressure steam pumping engine in 1802 may be taken as the
first pumping engine of the puffer class using such strong steam.

In the spring of the following year[61] a somewhat similar engine was
erected in London. "The cylinder is 11 inches in diameter, with a
3-1/2-feet stroke. It requires the steam at a pressure of 40 to 45
lbs. to the inch to do its work well, working about twenty-six or
twenty-seven strokes per minute. It is much admired by everyone that
has seen it, and saves a considerable quantity of coal when compared
with a Boulton and Watt. Mr. Williams, Mr. Robert Fox, Mr. Gould, and
Captain William Davey were here, and much liked the engine; they gave
me an order for one for Cornwall as a specimen." This particular engine
was for driving machinery in a cannon manufactory. A high-pressure
pumping engine was at work at Greenwich, and some were at work in
Cornwall.

[Footnote 61: See Trevithick's letter, May 2nd, 1803, vol. i., p. 158.]

  "PENYDARRAN, near CARDIFF,[**Check order of these lines]

  "MR. GIDDY,

  "_October 1st, 1803_.

 "Sir,--In consequence of the engine bursting at Greenwich, I have
 been on the spot to inspect its effects. I found it had burst in
 every direction. The bottom stood whole on its seating; it parted
 at the level of the chimney. The boiler was cast iron, about 1 inch
 thick, but some parts were nearly 1-1/2 inch; it was a round boiler,
 6 feet diameter; the cylinder was 8 inches diameter, working double;
 the bucket was 18 inches diameter, 21 feet column, working single,
 from which you can judge the pressure required to work this engine.
 The pressure, it appears, when the engine burst, must have been very
 great, for there was one piece of the boiler, about 1 inch thick and
 about 5 cwt., thrown upwards of 125 yards; and from the hole it cut
 in the ground on its fall, it must have been nearly perpendicular and
 from a very great height, for the hole it cut was from 12 to 18 inches
 deep. Some of the bricks were thrown 200 yards, and not two bricks
 were left fast to each other, either in the stack or round the boiler.
 It appears the boy that had care of the engine was gone to catch eels
 in the foundation of the building, and had left the care of it to one
 of the labourers; this man, seeing the engine working much faster than
 usual, stopped it, without taking off a spanner which fastened down
 the steam-lever, and a short time after being idle it burst, killed
 three on the spot and another died soon after of his injuries. The
 boy returned that instant, and was then going to take off the trig
 from the valve. He was hurt, but is now recovering; he had left the
 engine about an hour. I would be much obliged to you if you would
 calculate the pressure required to burst this boiler at 1 inch thick,
 supposing it to be a sound casting, and what pressure it would require
 to throw the materials the distance I have before stated, for Boulton
 and Watt have sent a letter to a gentleman of this place, who is about
 to erect some of those engines, saying that they knew the effects
 of strong steam long since, and should have erected them, but knew
 the risk was too great to be left to careless enginemen, and that it
 was an invention of Mr. Watt, and the patent was not worth anything.
 This letter has much encouraged the gentlemen of this neighbourhood
 respecting its utility; and as to the risk of bursting, they say it
 can be made quite secure. I believe that Messrs. Boulton and Watt are
 about to do me every injury in their power, for they have done their
 utmost to report the explosion, both in the newspapers and in private
 letters, very different to what it really was; they also state that
 driving a carriage was their invention; that their agent, Murdoch, had
 made one in Cornwall and shown it to Captain Andrew Vivian, from which
 I have been enabled to do what I have done. I would thank you for any
 information that you might have collected from Boulton and Watt, or
 from any of their agents, respecting their even working with strong
 steam, and if Mr. Watt has ever stated in any of his publications the
 effects of it, because if he condemns it in any of his writings, it
 will clearly show from that, that he did not know the use of it. Mr.
 Homfray, of this place, has taken me by the hand, and will carry both
 the engines and the patent to the test. There are several of Boulton
 and Watt's engines being taken down here, and the new engines being
 erected in their place. Above 700 horse-powers have been ordered at
 12_l._ 12_s._ for each horse-power for the patent right, and the
 persons that ordered them make them themselves, without any expense
 to me whatever. If I can be left quiet a short time I shall do well,
 for the engines will far exceed those of Boulton and Watt. The engine
 at Greenwich did fourteen millions with a bushel of coals; it was
 only an 8-inch cylinder, and worked without an expansive cock, and
 under too light a load to do good duty; also on a bad construction,
 for the fly-wheel was loaded on one side, so as to divide the power
 of the double engine, and connected to the pump-rods on a very bad
 plan. I remember that Boulton and Watt's 20-inch cylinders when on
 trial did not exceed ten millions; I believe you have the figures
 in your keeping. Let us have the 60-horse power at work that is now
 building, and then I will show what is to be done. It will be loaded
 at 30 lbs. to the inch on each side the piston, it has an 8-feet
 stroke with an expansive cock, and the blowing cylinder directly over
 the steam-cylinder, as free from friction as possible. There was no
 engine stopped on account of this accident; but I shall never let the
 fire come in contact again with the cast iron. The boiler at Greenwich
 was heated red hot and burnt all the joints the Sunday before the
 explosion.

 "I have received a letter from a person in Staffordshire who has a
 cylinder-boiler at work with the fire in it, and he says the engine
 performs above all expectation; he requests me to give him leave
 to build a great many more. I shall put two steam-valves and a
 steam-gauge in future, so that the quicksilver shall blow out in case
 the valve should stick, and all the steam be discharged through the
 gauge. A small hole will discharge a great quantity of steam at that
 pressure. There will be a railroad-engine at work here in a fortnight;
 it will go on rails not exceeding an elevation of one-fiftieth part
 of a perpendicular and of considerable length. The cylinder is 8-1/2
 inches in diameter, to go about two and a half miles an hour; it is to
 have the same velocity of the piston-rod. It will weigh, water and all
 complete, within 5 tons.

 "I have desired Captain A. Vivian to wait on you to give you every
 information respecting Murdoch carriage, whether the large one at Mr.
 Budge's foundry was to be a condensing engine or not.

 "Is it possible that this engine might be burst by gas?

  "I am, Sir,
  "Your very obedient servant,
  "RICHARD TREVITHICK."

This high-pressure puffer pumping engine at Greenwich, in 1803,
worked a pump of 18 inches in diameter. The engine boy having fixed
the safety-valve while he fished for eels, caused an explosion of
the boiler. This was the first mishap from the use of high-pressure
steam. The boiler was globular, 6 feet in diameter, and from an inch
to an inch and half in thickness, made of cast iron; the cylinder, of
8 inches in diameter, was partly let into and fixed on the boiler.
Its general design is seen in the patent drawing of 1802, Fig.
1.[62] Trevithick determined in future to use two safety-valves, and
also a safety steam-gauge. At that time one of his high-pressure
puffer-engines, with a cylindrical boiler and internal tube, was
working in Staffordshire.

[Footnote 62: See vol. i., p. 128.]

The Greenwich high-pressure puffer-engine did fourteen millions of
duty with a bushel of coals, 84 lbs. A 60-horse-power engine was being
built in Wales, with an 8-feet stroke, to work expansively with 30 lbs.
of steam on the inch in the boiler. For a more thorough test with the
low-pressure vacuum engines, in competition, the Government intended to
use the new engines, and some of Watt's engines having been removed to
make room for them, Boulton and Watt wrote to a gentleman who was about
to order an engine from Trevithick, "We knew the effects of strong
steam long since, and should have erected them, but knew the risk was
too great." Moreover, "it was an invention of Mr. Watt's, and the
patent (Trevithick's) was not worth anything." This admission clearly
shows not only that Watt did not make high-pressure steam-engines, but
that he did his best to prevent others from making them.

  "MR. GIDDY,        "PENYDARRAN, CARDIFF, _January 5th, 1804_.

 "Sir,--I received yours a few days since, and should have answered
 it sooner, but I was at Swansea for the last four weeks, and wished
 to return here to give you as full an account of our proceedings as
 possible.

 "We have had an 8-inch cylinder at work here by way of trial; it
 worked exceedingly well a hammer of the same size as is now being
 worked here by an atmospheric engine 28 inches diameter, 5-feet
 stroke, which does not master its work with greater ease than the
 8-inch cylinder. The 8-inch is now removed to Swansea, and is winding
 coals; the baskets hold 6 cwt. of coal; it lifts 80 yards in a minute
 and a quarter, and burns 6 cwt. of coal in twenty-four hours. There
 were twelve horses on this pit before, lifting 80 tons of coal in the
 course of the twenty-four hours. You may fairly state that the 8-inch
 cylinder does between thirty and forty horses' work in twenty-four
 hours, with 6 cwt. of coal.

 "One of Boulton and Watt's 18-inch double engine, about half a mile
 from it, lifting baskets of the same size, and with the same velocity,
 burns above three times the quantity of coal.

 "The 8-inch engine requires the steam to be about 46 or 48 lbs. to the
 inch to do its work well. The standers-by would not believe that such
 a small engine could lift a basket of coal, but are now much pleased
 with it, and have given orders for several more. There will be another
 at work here for the same purpose in about six weeks, a 15-inch
 cylinder, 6-feet stroke, which is a great power for a winding engine.

 "Mr. Watt says, in a letter to Mr. Homfray, that he could not make any
 of his experiments in strong steam answer the purpose. It is my belief
 that he never made any experiments of any consequence in strong steam.

 "A great number are building at different foundries. Mr. Sharratt, a
 founder at Manchester, who has four in building, said that he would
 not pay the patent right; on giving him notice of a trial he agreed to
 pay the patent right.

 "I have received a letter from London, saying that an engineer called
 Dixon has two engines on the same plan working; and says that he
 shall not pay anything to the patentee; that the words in Mr. Watt's
 specification are enough to indemnify him from my threats. We have
 had three counsels' opinions on the subject, and they all agree that
 the patent is good. Counsels Marratt and Gibbs principally treated
 on the construction of the engine, more than on the principle; but
 Erskine was principally on the principle of the engine, and said very
 little of its construction. They all say the words in Mr. Watt's
 specification will have no weight whatever against us.

 "I shall leave this place to-morrow for London to make inquiry into
 those engines, and to get the business into court if they will
 contend. I shall be at No. 2, Southampton Street, Strand, and expect
 to be in town about five or six days, and if you will be so good as to
 return here, from Oxford, with me, I will call on you in my journey
 down. It is but 50 miles from Bristol, and not so much as 100 miles
 from Oxford, and the coach passes very near this place.

 "There is a great deal of machinery and mining here, which would
 engage your attention for a few days, and very pleasant gentlemen
 about the neighbourhood.

 "If I had not been called to Swansea to put up the winding engine,
 the road-engine would have been at work long since, but in my absence
 very little was done to it. The work is all ready, and a part of it
 put together. If I could tarry four or five days longer I could set
 it to work before going to London. They promise me that it shall be
 completed before my return. I think there is no doubt of its being
 finished, as I have Frank Bennetts here from Cornwall about it, and a
 plenty of hands to assist him.

 "I have a thousand things to relate to you, too much for paper to
 contain, therefore must request you to be so good as to go down from
 Oxford with me, and I will promise, on warrant, that the road-engine
 shall be finished before my return. When it is set to work I shall
 return to Cornwall.

  "I remain, Sir,
  "Your humble servant,
  "RICHARD TREVITHICK."

In 1804 an 8-inch cylinder high-pressure puffer-engine, with steam
of 48 lbs. to the inch, worked a large hammer as well as a 28-inch
cylinder atmospheric engine, and more economically than a Watt
low-pressure steam vacuum engine with an 18-inch cylinder, which was
five times as large as the little high-pressure. In consequence of this
superiority those who came to witness the trial ordered several more of
Trevithick's engines, one of which with a 15-inch cylinder and 6-feet
stroke was to be at work in a few weeks.

Watt wrote to Mr. Homfray "that he could not make any of his
experiments in strong steam answer the purpose," and Trevithick
declared Watt never could have tried any experiments with high steam.

Dixon refused to pay patent right because the words of Mr. Watt's
specification, "in cases where cold water cannot be had in plenty, the
engines may be wrought by the force of steam only, by discharging the
steam into the open air after it has done its office," "are enough to
indemnify him." Eminent counsel were of opinion that "the words in
Watt's specification will have no weight whatever."

Marratt and Gibbs were inclined to rest on the difference in the
construction of the two kinds of engines, while Erskine boldly said
that the principle was different, and he cared little for the kind of
construction.

The admission by Watt that he could do nothing with high steam after
an experience of thirty years from the date of his patent, shows how
difficult the work was to those who had to find the way; yet Trevithick
had several at work within a few months of his first mental sight of a
steam-engine without condensing water, fitful glimpses of which passed
and repassed while he sat unobserved in the crowded law court in 1796
hearing the remarks of engineers and counsel.

 "The public until now called me a scheming fellow, but their tone is
 much altered. An engine is ordered for the West India Docks, to travel
 itself from ship to ship, to unload and to take up the goods to the
 upper floors of the storehouses.

 "Boulton and Watt have strained every nerve to get a Bill in the House
 to stop these engines, saying the lives of the public are endangered
 by them, and I have no doubt they would have carried their point, if
 Mr. Homfray had not gone to London to prevent it; in consequence of
 which an engineer from Woolwich was ordered down, and one from the
 Admiralty Office, to inspect and make trial of the strength of the
 materials."[63]

[Footnote 63: See Trevithick's letter, 22nd February, 1804, vol. i., p.
161.]

After a week or two another letter states,[64]--

 "We are preparing to get the materials ready for the experiments by
 the London engineers, who are to be here on Sunday next. We have fixed
 up 28 feet of 18-inch pumps for the engine to lift water.

 "These engineers particularly requested that they might have a given
 weight lifted, so as to be able to calculate the real duty done by a
 bushel of coal.

 "As they intend to make trial of the duty performed by the coal
 consumed, they will state it as against the duty performed by
 Boulton's great engines, which did upward of twenty-five millions,
 when their 20-inch cylinders, after being put in the best order
 possible, did not exceed ten millions. As you were consulted on all
 those trials of Boulton's engines, your presence would have great
 weight with those gents, otherwise I shall not have fair play. Let
 me meet them on fair grounds and I will soon convince them of the
 superiority of the '_Pressure-of-steam engine_.'"

[Footnote 64: See Trevithick's letter, 4th March, 1804, vol. i., p. 166.]

Watt left no stone unturned to prevent the use of high-pressure
steam-engines, and fortune favoured him, for after four or five days
Trevithick again wrote:--

 "I am sorry to inform you that the experiments that were to be
 exhibited before the London gents are put off, on account of
 an accident which happened to Mr. Homfray. I find myself much
 disappointed on account of the accident, for I was desirous to make
 the engine go through its different work, that its effect might be
 published as early as possible."[65]

[Footnote 65: See Trevithick's letter, 9th March, 1804, vol. i., p. 168.]

While constructing those numerous high-pressure engines for rolling
mills, winding engines, and pumping engines, the Welsh and Newcastle
locomotives were being made and worked, yet he found time to teach the
people of Stourbridge.

  "MR. GIDDY,           "STOURBRIDGE, _July 5th, 1804_.

 "Sir,--I should have answered your letter some time since, but waited
 to set two other engines to work first. The great engine at Penydarran
 goes on exceedingly well. The engine will roll 150 tons of iron a week
 with 18 tons of coal. The two engines of Boulton's at Dowlais burn
 40 tons to roll 160 tons; they are a 24-inch and a 27-inch double.
 The engine at Penydarran is 18-1/2 inches, 6-feet stroke, works
 about eighteen strokes per minute: it requires the steam about 45
 lbs. to the inch above the atmosphere. I worked it expansive first,
 when working the hammer, which was a more regular load than rolling;
 then with steam high enough to work twelve strokes per minute with
 the cock open all the stroke; then I shut it off at half the stroke,
 which reduced the number of strokes to ten and a half per minute,
 the steam and load the same in both; but I did not continue to work
 it expansively, because the work in rolling is very uneven, and the
 careless workmen would stop the engine when working expansive.

 "When the cylinder was full of steam the rollers could not stop it;
 and as coal is not an object here, Mr. Homfray wished the engine
 might be worked to its full power. The saving of coal would be very
 great by working expansively.

 "The trials we have made for several weeks past against Boulton's
 engines have been by working with the cylinder full of steam. The
 cock springs out of its seat when water gets into the cylinder, and
 prevents any mischief from the velocity of the fly-wheel.

 "The tram-engine has carried two loads of 10 tons of iron to the
 shipping place since you left this. Mr. Hill says he will not pay the
 bet, because there were some of the tram-plates in the tunnel removed
 so as to get the road into the middle of the arch.

 "The first objection he started was that one man should go with the
 engine, without any assistance, which I performed myself without help;
 and now his objection is that the road is not in the same place as
 when the bet was made.

 "I expect Mr. Homfray will be forced to take steps that will force him
 to pay. As soon as I return from here there will be another trial, and
 some person will be called to testify its effects, and then I expect
 there will be a lawsuit immediately. The travelling engine is now
 working a hammer.

 "At Worcester last week we put a 10-horse engine to work in a glover's
 manufactory. The flue from the engine is carried through the drying
 room and dries his leather. The steam from the engine goes to take
 the essence out of the bark, and also to extract the colour out of
 the wood for dyeing the leather. Then it boils the dye, and the steam
 that is left is carried into his hot-house. It works exceedingly well.
 This week I put another to wind coals at this place, a 10-horse power,
 which works very well. All the tradesmen are set against it; they say
 that there is no carpenter or mason work about it, and very little
 smith-work, and that it will destroy their business. The engineer on
 the spot is also against it very much. I do not expect that it will be
 kept long at work after I leave it, unless the proprietor takes care
 to prevent those people from doing an injury to it. Mr. Homfray was
 here yesterday, but is now returned to Penydarran. I shall go from
 here to Coalbrookdale.

 "There is an engine there almost ready for the West India Docks. It
 will be ready to send off to London in about four weeks. It will be a
 very complete engine. The pumps for forcing the water will be fixed on
 the back of the boiler. It will force 500 gallons of water 100 feet
 high in a minute; above ten times the quantity that engines worked by
 men can do. Mr. Homfray and myself shall be in town as soon as the
 castings are sent off. I hope you will be there at the time. If you
 wish to see the engines already at work in London, call on Mr. David
 Watson, steam-engine maker, Blackfriars Road. He lives up about 500
 or 600 yards above the bridge on the left-hand side; you will see his
 name over his door. If you have time to inspect those engines you will
 find by comparing them against Boulton's, doing the same work, that
 there is a great saving of coal above other engines.... I shall go to
 Liverpool and Manchester from here, and again to Coalbrookdale.

 "There are three engines at the Dale begun, to work with condensers,
 for places where coal is scarce. I think it is better to make them
 ourselves, for if we do not, some others will, for there must be a
 saving of coal by condensing. But with small engines, or where coal is
 plentiful, the engine would be best without it. They say at the Dale
 about putting two cylinders, but I think one cylinder partly filled
 with steam would do equally as well as two cylinders.

 "That engine at Worcester shuts off the steam at the first third of
 the stroke, and works very uniformly. I cannot tell what coal it
 burns yet, but I believe it is a very small quantity. I shall know in
 a short time what advantage will be gained by working expansive. I
 expect it will be very considerable. There are a great many engines
 making and ordered. Boulton and Watt and several others are doing
 everything to destroy their credit, but it is impossible to destroy
 it now that it is so well known. I have not taken any of the ground
 at Bristol to remove. I called on them and told them it was possible
 to break the ground without men, and they wish me to take a piece to
 clear out, but would not set but a small piece at a time; therefore
 it would be disclosing the business to no purpose. They were very
 desirous to know the plan, but I would not satisfy them, neither will
 I unless they pay me for it in some way or other. If you direct for me
 at the Dale it will find me. I am happy to find that you have a seat
 in the House. I wish every seat was filled with such.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK."

Trevithick fully understood the value of the expansive principle in
1804: when working with steam of 45 lbs. to the inch, the engine went
at a speed of twelve strokes a minute. On cutting off the steam at
half-stroke, the speed and consequent work done fell to ten and a half
strokes a minute; in other words, the work performed by the engine fell
off only one-eighth part, while the quantity of steam and consequently
of coal was reduced by one-half. The principle was established, but
the application was practically incomplete from the want of heavier
fly-wheels, to give out their momentum during the latter half of the
stroke, when the expanding steam was lessening its force.

"The saving of coal would be very great by working expansively,
but as coal is not an object here," Mr. Homfray was careless about
the expansion. Thirty-three years after this indirect check to
steam-engine economy, the writer, then living in the Sirhowey Iron
Works, and within stone's-throw of Mr. Homfray's Works, recommended
the removal of the Boulton and Watt's waggon boilers, to make room
for Trevithick's boilers, on the plea of saving one-half the fuel,
and at the same time increasing the power of the engine, and thereby
the pressure of the blast in the iron furnaces. The proprietor was
careless about the saving of coal, and was doubtful that an increased
blast would increase the quantity of iron smelted. The promise that
the wages of one-half of the number of boiler firemen would be saved,
was understood. Trevithick's high-pressure boilers replaced the Watt
low-pressure, resulting in a largely-increased quantity of iron from
the greater power and pressure of blast in the furnaces, and at
one-half the expenditure of coal in the boilers: ten men had been
employed as firemen of the Watt boilers during twenty-four hours; with
Trevithick's boilers, five men did the work.

The high-pressure puffer-engine, with an 18-inch cylinder, working with
45 lbs. of steam, rolled as much iron as the two larger low-pressure
vacuum engines of Watt, of 24 and 27 inch cylinders, which together
were more than three times the size of the high-pressure engine, and
cost three times as much.

At Stourbridge, as elsewhere, everyone was against the new plan. The
engineer in charge did not like it, and the carpenters, smiths, and
masons saw the end of their occupation as engine erectors, if there was
no longer a necessity for foundations, well-work, &c., for condensing
water, and many other things, necessary to complete a Watt engine;
while the high-pressure puffer was no sooner unloaded than it was ready
to work.

A great charm in Trevithick's character was his freedom and largeness
of view in questions of competition. He was then making three engines
at Coalbrookdale, to be worked with high-pressure steam, combined with
the Watt air-pump and condenser; and though smarting from the contest
with his great rival, yet wrote, "I think it is better to make them
ourselves, for if we do not, some others will, for there must be a
saving of coal by condensing. But with small engines, or where coal is
plentiful, the engine would be best without it."

Those words accurately describe the practice of the present day, though
written sixty-six years ago, and were followed by others equally true
in principle, though varied in form to suit special requirement. "They
say at the Dale about putting two cylinders, but I think one cylinder
partly filled with steam would, do equally as well as two cylinders."

These sagacious views required the untiring labour of the following
twelve years to perfect and make practical, when applied to the largest
engines of the time; which we shall now trace in the construction of
a strong and economical boiler, supplying high-pressure steam to the
cylinder during only a comparatively small portion of the stroke,
completing it by expansion, so that at its finish the steam had become
of low pressure when passed to the condenser. The moving parts and
expansive gear were so simplified as to be applicable to the then
existing low-pressure steam vacuum engines without the complication of
the double cylinders of Hornblower and Woolf.

  "DEAR SIR,        "PENYDARRAN PLACE, _December 26th, 1804_.

 "I have been favoured with your letter, and in answer, respecting Mr.
 Mitchell, I am at a loss to know from your letter what kind of iron he
 may likely want. If you will direct him to write to me, and explain
 himself, I will immediately reply to him and do what I can to assist
 and serve him. I believe there are vessels going over frequently from
 Cardiff to Cornwall with coals, that he might have part in cargo and
 the remainder in coals. I am happy to give you the most satisfactory
 account of our 'Trevithick's engine' going on well. It has now been
 at work many months, and is by far the best engine we have. We have
 for weeks weighed the coal, and knowing the work it does, can speak
 with confidence. Its 18 inches diameter steam-cylinder consumes as
 near as can be 3 tons of coal in twenty-four hours, or 18 tons per
 week; and in this time it rolls with ease 130 tons long weight of
 iron from the puddling furnaces, at the same heat, into bars of 3
 inches by about half an inch thick. Now, one on Messrs. Boulton and
 Watt's plan, of '24 inches' steam-cylinder, at our neighbouring
 works at Dowlais, employed in doing exactly the same kind of work,
 consumes _full_ as much coal, and rolls only 90 tons in the week.
 These being facts, open for any person daily to see, must convince
 any dispassionate man of the superiority of 'Trevithick's engines,'
 and that the saving of fuel is nearly one-third, besides the other
 advantages of saving water and grease, which is no little. The
 packing of the piston now gives us little or no trouble, it goes
 from a fortnight to a month, opening the top now and then to screw
 it down, as it gets slack, which should be attended to. We use no
 grease or oil in packing the piston or working the engine, having
 found blacklead mixed with water, and poured 'a little now and then'
 through a hole on the top into the steam-cylinder, suits the packing
 of the piston much better, and is cheaper than anything else. About
 1_s._ worth of blacklead will last our engine a week. We are now so
 thoroughly convinced of the superiority of these engines that I have
 just begun another of larger size. The boiler is to be 24 or 26 feet
 long, 7 feet diameter, fire-tube at wide end 4 feet 4 inches, and at
 narrow end, where it takes the chimney, 21 inches, steam-cylinder 23
 inches diameter. This boiler, on account of the length of its tube
 withinside, will, I have no doubt, get steam in proportion, and work
 the engine with much less coals than our present one. Trevithick is
 at Coalbrookdale, Manchester, &c., &c., very busy, a great number
 of engines being in hand in that part of the world; and I think by
 perseverance the prejudice is wearing away very fast, and in spite of
 all Messrs. Boulton and Watt's opposition, they must and will take the
 lead of theirs. Any person now wanting engines, must be next kin to an
 idiot to erect one of Boulton's in preference to Trevithick's. I find
 there is a small one making near you by Mr. Vivian. I hope they have
 corresponded with Trevithick about the proportions of it; if they
 have not, I shall be particularly obliged to you to desire them to do
 so, for by his experience of what he has done they may be benefited,
 for it would be a shocking thing to have a bad engine put up for the
 first time in his native county.

 "Mrs. Homfray unites with me in best compliments, and wishing you many
 happy returns of the season.

  "I remain, dear Sir,
  "Your most obedient servant,
  "SAMUEL HOMFRAY.

  "_To Mr. Davies Giddy._"

The evidence in this contest between the Watt low-pressure steam
vacuum engine and the Trevithick high-pressure steam-puffer engine is
in favour of the new principle; for the steam-engine with an 18-inch
cylinder did fifty per cent. more work than the vacuum engine with a
24-inch cylinder with an equal quantity of coal, though the latter was
seventy-five per cent. larger than the former; and a still greater
economy was expected from the larger boiler to be built, 26 feet long,
7 feet in diameter, with internal fire-tube 4 feet 4 inches diameter at
the fire end, tapering to 21 inches at the chimney end.

Thus in 1804 the cylindrical boiler in Wales had nearly reached its
present form, and Homfray thought that none but idiots would prefer the
Watt engine; forgetting that Trevithick's near friends and neighbours
were carrying on a similar contest at Dolcoath Mine.

  "PENYDARRAN PLACE, _January 2nd, 1805_.

  "MR. DAVIES GIDDY,

 "Dear Sir,--I have duly received your favour enclosing a letter for
 Mr. Trevithick, and which I, according to your desire, forwarded to
 him at Manchester, where he now is; and a letter directed to him, to
 the care of Mr. Whitehead, Soho Foundry, Manchester, will find him, as
 he will stay a little time there, being very busy. I had lately the
 pleasure of writing to you, and gave you the account of our engine
 working, and the satisfaction it gives; I have nothing more to add
 on the subject, but that it is now at work, going on as usual, and I
 should be happy for you to have a sight of it.

 "We are beginning another of a larger size, and I have no doubt but
 by making the cylindrical boiler larger, so as to take a longer tube
 withinside it, by which means the fire will spend itself before it
 leaves the tube to go up the chimney, that we shall work to much
 better advantage in point of fuel than we do at this present one, as
 this boiler is so short that a great deal of the flame of the fire
 goes up the chimney. We are now better acquainted with the different
 proportions than we at first were, for which reason I am anxious
 that one now making by Mr. Vivian should be made according to the
 directions of Mr. Trevithick.

 "I beg leave to offer you the compliments of the season, and many
 happy returns, and

  "Remain, respectfully, dear Sir,
  "Your most obedient servant,
  "SAMUEL HOMFRAY."

Trevithick, always busy, was just now doing the work of a host, for
everybody had to be taught how to make high-pressure steam-engines; and
the Newcastle locomotive, the Thames steam-dredging, and other special
applications of steam-power required his presence, especially the fight
with Watt at Dolcoath Mine, where Andrew Vivian, as mine manager, was
erecting a high-pressure steam-puffer whim-engine to compete with a
Watt low-pressure steam vacuum whim-engine.

 "The adventurers grumbled because Captain Trevithick was so often away
 from the mine. Glanville, the mine carpenter, the head man over the
 engines, made a trial between Trevithick's high-pressure puffer whim
 and Watt's low-pressure condenser. When Captain Trevithick heard of
 it, he wrote down from London that he would bet Glanville 50_l._ that
 his high-pressure puffer should beat Watt's low-pressure condenser.
 Then he came down from London and found that the piston of his engine
 was half an inch smaller in diameter than the cylinder. When a new
 piston was put in, she beat Boulton and Watt all to nothing. Persons
 were chosen to make a three or four weeks' trial, and when it was
 over, 'a little pit was found with coal buried in it, that Glanville
 meant to use in the Watt engine.'"[66]

[Footnote 66: Recollections of Henry Clark, living at Redruth in 1869.]

Pooly, Smith, and others, say that Trevithick's Dolcoath puffer had
the outer case of the boiler of cast iron, the fire-tube of wrought
iron, the cylinder horizontal, and fixed in the boiler. Captain Joseph
Vivian saw Trevithick's whim in Stray Park Mine about 1800 or 1801,
and a similar one was erected in Dolcoath, and after a year or two a
Boulton and Watt low-pressure whim was put up to beat it. The trial was
in favour of the Watt engine, but everybody said the agents were told
beforehand which way the report ought to go; so the engine that _puffed
the steam up the chimney_ was beaten.

Trevithick, who was busily engaged in Manchester at that time, the
early part of 1805, when informed of what was going on in Cornwall,
wrote:--

 "I fear that engine at Dolcoath will be a bad one. I never knew
 anything about its being built until you wrote to me about Penberthy
 Crofts engine, when you mentioned it. I then requested Captain A.
 Vivian to inform me the particulars about it, and I find that it will
 not be a good job. I wish it never was begun."[67]

[Footnote 67: See Trevithick's letter, January 10th, 1805, vol. i., p.
324.]

  "MR. GIDDY,          "CAMBORNE, _February 18th, 1806_.

 "Sir,--On my return from town I altered the pressure of the
 steam-engine at the bottom of the hill, Dolcoath. Before I returned
 there was a trial between mine and one of Boulton's; both engines in
 the same mine and drawing ores from the same depth. The result was,
 Boulton's beat the pressure-engine as 120 to 55. Since it was altered
 there have been three other trials; the result was 147 to 35 in favour
 of the pressure of the steam-engine. They are now on trial for another
 month, and at the next account _they intend to order a new boiler for
 the great engine_, and work with high-pressure steam and condenser,
 provided this engine continues to do the same duty as was done in the
 former trials. This engine is now drawing from a perpendicular shaft,
 and Boulton and Watt's from an underlay shaft; but to convince Captain
 Jos. Vivian, we put it to draw out of the worst shaft in the mine, and
 then we beat more than three to one; we lifted in forty-seven hours,
 233 tons of stuff 100 fathoms with 47 bushels of coal. The engine was
 on trial sixty-six hours, but nineteen hours were hindered by the
 shaft and ropes, &c., which made the consumption of coals about 3/4ths
 of a bushel per hour. The fire-tube is 2 feet 3 inches diameter, and
 the fire-bars were only 14 inches long. The fire-place was but 2 feet
 3 inches wide by 14 inches long, and the fire about 4 or 5 inches
 thick; it raised steam in plenty; it was as bright as a star. The
 engine is now doing the work of two steam-whims; the other steam-whim
 in the Valley is turned idle, and both shafts will not more than half
 supply it. 233 tons are equal to nearly 2000 kibbals, which were drawn
 in forty-seven hours.

 "Mr. Harris has a 12-inch cylinder making at Hayle, for Crenver, and
 Mr. Daniel has a 14-inch for Perran-sand, and a great number are
 waiting for the trial of this month, _before altering their boilers to
 the great engines_.

 "The steam-whim that is now turned idle at the Valley was 13-1/2-inch
 cylinder, 4-feet stroke; it turned the whim one revolution to one
 stroke, and lifted the kibbal the same height at a stroke as my
 engine did, and I think took the same number of gallons of steam to
 lift a kibbal as mine did. Their steam was not above 4 lbs. to the
 inch; _mine was near 40 lbs. to the inch_; yet I raised my steam of
 near 40 lbs. with a third of the coals by which they got theirs of
 4 lbs. to the inch. This is what I cannot account for, unless it is
 by getting the fire very small and extremely hot. Another advantage
 I have is, that there is no smoke that goes off from my fire to clog
 the fire sides of the boiler, while the common boilers get soot half
 an inch thick, and the mud falls on the bottom of the boiler, where
 the fire ought to act; but in these new boilers the mud falls to
 the bottom, where there is no fire, and both the inside and outside
 of the tube are clean and exposed both to fire and water. This
 fire-*place[**hyphenated below] of 14 inches was 5 feet long when I
 came down, and then the coal did not do above one-seventh of the duty
 that it now does.

 "I would be very much obliged to you for your opinion on what I have
 stated, and what _advantage you think the great engine is likely to
 get from working with steam about 25 lbs. to the inch, and shut off
 early in the stroke, so as to have the steam about 4 lbs. to the inch
 when the piston is at the bottom. I think this, with the advantage of
 the fire-place, will make a great saving._

 "The present fire-place is 22 feet from fire-door to fire-door, 9 feet
 wide, and 7 feet thick in fire. There is not one-tenth of the coals
 that are in the fire-place on fire at the same time; it will hold 30
 tons of coals at one time, and I think that a great deal of coal is
 destroyed by a partial heat before it takes fire. A boiler on the
 new plan will not cost more than two-thirds of the old way, and will
 last double the time, and can be cleaned in three hours. It requires
 twenty-four hours in the old way, and we need to clean the boilers
 only one-fourth the number of times.

 "Though these trials have shown so fairly that it is a great
 advantage, my old acquaintances are still striving with all their
 might to destroy the use of it; but facts will soon silence them.

 "I am about to enter into a contract with the Trinity Board for
 lifting up the ballast out of the bottom of the Thames for all the
 shipping. The first quantity stated was 300,000 tons per year, but
 now they state 500,000 tons per year. I am to do nothing but wind up
 the chain for 6_d._ per ton, which is now done by men. They never
 lift it above 25 feet high. A man will now get up 10 tons for 7_s._
 My engine at Dolcoath has lifted above 100 tons that height with 1
 bushel of coals. I have two engines already finished for this purpose,
 and shall be in town in about fifteen days to set them at work. They
 propose to engage with me for twenty-one years. The outlines of the
 contract they have sent me down, which I think is on very fair terms.
 I would thank you for your answer before I leave this county.

  "I am, Sir,
  "Your very humble servant,
  "RD. TREVITHICK."

In the trial at Dolcoath during his absence the high-pressure
steam-puffer whim was beaten by Watt's low-pressure steam vacuum
whim-engine as 55 to 120; but having corrected some oversight in the
puffer-engine, it then beat Watt as 147 to 35. The trial was to be
continued for a month; and provided the superiority of his whim-engine
could be maintained, the adventurers would allow him to apply his
high-pressure boilers to their large Boulton and Watt pumping engine.
The trial with the whim-engines was for the greatest number of kibbals
of mineral raised to the surface by the least consumption of coal. A
dispute arose on the difference of the shafts, the one causing more
friction to the moving kibbal than the other, when Trevithick agreed
to take the worst shaft in the mine. On a trial during sixty-six hours
Watt's engine was beaten by more than four times; and as Trevithick's
engine did the work that before required two engines, one of the
low-pressure steam Watt engines was removed that the engine working
with 40 lbs. on the inch might perform the whole work.

"My fire-tube is 2 feet 3 inches in diameter, and the fire-bars only
14 inches long, and the fire only about 4 or 5 inches thick; it raised
steam in plenty, and was as bright as a star." These words certainly
imply the use of the blast-pipe, making the fire as bright as a star,
and enabling the small boiler to give the required supply of steam.
Several high-pressure puffer-engines had been ordered, and many persons
were waiting the conclusion of the month's public trial to enable them
to judge between the Watt and the Trevithick engine.

  "MR. GIDDY,           "CAMBORNE, _March 4th, 1806_.

 "Sir,--The day after I wrote to you the first letter, I received
 yours, and this day I have yours of the 1st instant.

 "I am very much obliged to you for the figures you have sent me. I am
 convinced that the _pressure of steam will not hold good as theory
 points it out, because on expanding it will get colder, and of course
 lose a part of its expansive force after the steam-valve shuts_. I
 think there can be no risk in making this trial on Dolcoath great
 engine, as they intend to have a new boiler immediately, so as to
 prevent stopping to cleanse; and a boiler on this new plan can be
 made for one-third less expense than on the old plan, when you count
 the large boiler-house and ashes-pit, and brickwork round the boiler.
 It is not intended to alter any part of the engine or condenser, but
 only work with high steam from this new boiler; and if this boiler
 only performs as good duty as the old one, it will be a saving of near
 300l. to them on the erection. _The vast matter this great engine has
 in motion will answer in part the use of a fly-wheel_: the whole of
 the matter in motion is near about 200 tons, at a velocity of about
 160 feet a minute. This I know will not be sufficient; but it will be
 about equal to a fly-wheel of 20 feet diameter, 25 tons weight, twenty
 rounds per minute, if weight and velocity answer the same purpose.

 "Since Monday, the 18th February, being Dolcoath account-day, both
 engines have been on trial, and are to be continued until the next
 account, 17th instant. The engines are kept on in the usual way, as
 at other times. Neither of the engines have done so much duty as on
 the first trials, as they have not been so strictly attended to. The
 average of the trial at this time stands 26 cwt. for a bushel of coals
 to Boulton and Watt's engine; mine, 83 cwt. for a bushel of coals.

 "If I do not remain in Cornwall to attend next Dolcoath account, I
 shall be in town about the 15th instant, otherwise about the 20th
 instant. I shall call on you immediately on my arrival. In this time
 I should be glad to hear from you again. The Trinity business will
 answer exceedingly well; I have two engines ready for that purpose to
 put to work on my arrival in town.

  "I am, Sir,
  "Your very humble servant,
  "RD. TREVITHICK.

 "P.S.--I would try the evaporation of water by both boilers, but
 Boulton and Watt's engine is so pressed with work, and being on the
 best part of the mine, they will not stop it a moment. A boiler of 8
 feet diameter and 30 feet long will have as much fire-sides in the
 tube as there is now in Dolcoath great boiler. The fire-tube in this
 boiler would be 5 feet diameter, and a fire-place 6 feet long in it
 would be 30 feet of fire-bars. In the whim-engines I find that a
 fire-place 14 inches long and the tube 2 feet 3 inches diameter would,
 being forced, burn 1 bushel per hour. At this rate the great tube
 would burn near 12 bushels per hour, which is above the quantity that
 the great engine boiler can consume, now at work. Small tubes would
 have an advantage over large ones. Two boilers would not cost much
 more than one large one, and be much stronger."

The battle-ground of the fight between low and high pressure from 1806
to 1812 had also served for the personal encounter of Trevithick, sen.,
and Watt a quarter of a century before, when the Dolcoath great pumping
engine was erected to compete with the two earlier atmospherics; all
three were still at work, overlooked by Carn Brea hill and castle, once
the resort of Druid priests, whose sacrificial rites are still traced,
by the hollows and channels for the blood of victims on the granite
rocks.

[Illustration: CARN BREA CASTLE. [W. J. Welch.]]

  "MR. GIDDY,        "CAMBORNE, _March 21st, 1806_.

 "Sir,--The trial between the two engines ended last Monday, which
 was Dolcoath day. Boulton and Watt's engine, per average of trial,
 1 ton 20 cwt. 2 qrs., with 1 bushel of coals; the other, 5 tons 11
 cwt. 3 qrs., with 1 ditto, the same depth of shaft. The adventurers
 ordered the new castings that were made for another of Boulton and
 Watt's engines to be thrown aside, and another new engine of mine to
 be built immediately. The great boiler for the old engine is not yet
 ordered.

 "I have received orders for nine engines within these four weeks, all
 for Cornwall. Two 12-inch cylinders, two 16-inch ditto, three 9-inch
 ditto, one 8-inch ditto, one 7-inch ditto. I expect one will be put to
 work next week at Wheal Abraham, for lifting water.

 "This day I shall leave Cornwall for London. Shall stop two days in
 the neighbourhood of Tavistock, and take orders for three engines. As
 soon as I arrive in town I will call at your lodgings. I expect that
 the patent will be brought into court about the end of May. A person
 in Wales owes us about 600_l._ patent premium, and he says that the
 patent is not good. More particulars you shall have on my arrival.

 "The railroad is going forward. I have the drawings in hand for the
 inclined plane.

  "I am, Sir,
  "Your very humble servant,
  "RD. TREVITHICK."

The fact that expansion of steam caused reduction of heat was so
evident to Trevithick that he ventured to doubt his friend's theory.
The trials between the whim-engines having continued a fortnight,
showed that the high-pressure steam-puffer had lifted 83 cwt., while
the low-pressure steam vacuum only lifted 26 cwt. with the consumption
of a bushel of coal. A suitable high-pressure boiler for the Watt
low-pressure steam 63-inch pumping engine should be 30 feet long,
8 feet in diameter, with an internal fire-tube 5 feet in diameter;
proportions approved of in the present day. The recommendation in 1806
to use small tubes may claim to be the first practical decision on the
advantage of tubular boilers; and at the same time we read of the first
hesitating step on the part of the public to use high-pressure steam
in a Watt low-pressure engine, which was still deferred for further
consideration, even with the limited pressure of 25 lbs. to an inch;
so the large Watt pumping engines were doomed for another four or five
years to struggle through their work with low-pressure steam, though at
that time Cook's Kitchen high-pressure expansive condensing whim-engine
had been for years at work close by.

The shareholders professed to have fear of explosion; but party-feeling
and ignorance were the real causes of opposition, for working men had
no dread of the new engines, while influential men leaned toward Watt's
old-fashioned plans.

This fear of Trevithick's expansive plans and high steam is the more
surprising, because at that time a new boiler was required for the Watt
63-inch cylinder pumping engine and Trevithick's cylindrical tubular
boiler could be made for one-third less cost than the Watt waggon
boiler, thus saving 300_l._, and in addition he promised to apply the
higher pressure of steam to the Watt engine without any change in
its parts or expenditure of money, and make it set in motion at the
commencement of the stroke the 200 tons of pump-rods, the momentum of
which would, with the expansion of the steam, when shutting it off soon
after the first start in the movement of each stroke, carry it through
to the end; and he practically compares this advantage from hoarded
momentum in the pumping engine with his experience of the fly-wheel of
the rolling-mill expansive engine in Wales.

The whim-engine with a fire-tube 2 feet 3 inches in diameter used 84
lbs. of coal per hour; and at that rate one cylindrical boiler 30 feet
long, 8 feet in diameter, with internal fire-tube 5 feet in diameter,
would supply steam for Watt's 63-inch cylinder; but in place of it he
preferred two smaller boilers, because small tubes have an advantage
over large ones, and are much stronger.

The whim trials--high-pressure puffer against low-pressure vacuum--went
on for another fortnight, when high pressure, having done twice as
much work as low pressure, with an equal consumption of coal, the
adventurers threw aside the work that had been made for another Watt
engine, ordering one in its stead from Trevithick; but they could not
just then make up their minds to place the Watt 63-inch pumping engine
in his hands.

  "DEAR SIR,        "CAMBORNE, _May 30th, 1806_.

 "I am very happy to find you have so far continued your agreement with
 the Trinity gents, and think the bargain is a good one. Must still beg
 leave to remind you not to proceed to show what your engine will do
 till the agreement is fully drawn up and regularly signed.

 "Dolcoath agents, since they are informed of the accident at the
 iron-works in Wales, _of the engine blowing to pieces_, have requested
 me to have your opinion whether the old cylinder is strong enough for
 the boiler of the intended new engine, or whether you would recommend
 them to have a new one. Your answer to this as soon as possible, as
 Mr. Williams and some others are likely to make some objections.

 "Mr. Sims, the engineer, has published in the Truro paper, that one of
 Boulton and Watt's engines at Wheal Jewell has drawn more than a ton
 of ore over and above that drawn by the Dolcoath engine from the same
 depth by a bushel of coal. On inquiry I found they had only tried for
 twenty-two hours. They said they left off with as good a fire as they
 began with. This I argued was not a fair trial. They say they are now
 on a trial for a month.

 "The little engine at Wheal Abraham does its duty extremely well. The
 particulars as to consumption of coal cannot be fairly ascertained, as
 she has never been covered, is fed with cold water, and has not water
 to draw to keep her constantly at work.

 "I wish I could give a better account of the mines than is in my power
 to give, or of the standard price for ore, though the latter is rather
 looking up than otherwise. Our friend, North Binner Downs, is better
 than paying cost, but very little. At present the levels are all poor;
 the lode in the west shaft has underlayed faster than the shaft, and
 we have not seen it for several fathoms. The ground lately in the
 shaft has been cleaner killas, and if any alteration, better ground.
 It is now 9 fathoms under the 55-fathom level, and we are driving to
 cut the lode. The ground in the cross-cut is harder than when you were
 on the spot. The water is sinking in old Binner; it is about 7 fathoms
 under the adit in the western part, and deeper in the eastern part; we
 do not account for this. Wheal St. Aubyn combined poor. Wheal Abraham
 looks promising, and Creuver about paying cost. Dolcoath is better
 than when you left us, or when I was in London. The last sale was only
 about 800 tons. The next sale on Thursday is upwards of 1100 tons, and
 we expect a little better standard.

 "I wish you could discover who that old gent is that wanted a large
 slice in Dolcoath, that I might get at him through some unknown
 channel, for I want money sadly.

 "Cook's Kitchen continues poor, Tin Croft ditto; Wheal Fanny not rich.
 We had a pretty little fight last account there with T. Kevill and W.
 Reynolds, Esquires: black eyes and bloody noses the worst effects. T.
 Kevill's face was much disfigured, and he might have found a new road
 out of his coat.

 "At a meeting of Condurrow adventurers yesterday, twenty-four of them
 agreed to have one of our engines, cylinder 12 inches in diameter and
 6-feet stroke, provided the Foxes do not object to it. When the order
 is given I shall write to Mr. Hazeldine, provided I do not hear from
 you that it is better to send the order to any other place.

 "If you have occasion to write Mr. Hazeldine, I wish you would press
 him to hasten the engines for Wheal Goshen, &c.

 "I am served with a Vice-warden's petition by Mr. Harris for not
 working the Weith mine in a more effectual manner, and he prays the
 Vice-warden to make the sett void. The trial will come on some time
 the beginning of July, and by that time I suppose we shall have two
 fire-engines working thereon.

 "Had Mr. Harvey done as he was desired we should have had one working
 there at this time, but he has but now begun to do anything to it. We
 have the cylinder and ends home from Polgooth, and my cousin Simon
 Vivian is making the tubes. We have the other cylinder from Wheal
 Treasury, and I have ordered Horton to cast a cock for it the same as
 that at Dolcoath. We have cut the south lode at the adit level about
 50 or 60 fathoms east of the engine, and have driven about 20 fathoms
 on it. It turns out about half a ton per fathom at 20_l._ a ton. The
 ground at 40_s._ per fathom; this all in a hole, and is better going
 down. The back is sett to four men at 3_s._ 11_d._; their time is out
 this week, and I suppose they must have 5_s._ next. This may turn out
 a few thousands, and I think too promising a thing to give up to Mr.
 Harris.

 "I am happy to inform you that all our friends are in good health, and
 beg my most respectful compliments to Mrs. Rogers and adopted son; and
 am,

  "Dear Sir,
  "Yours very sincerely,
  "ANDW. VIVIAN.

 "The promised news respecting the engine business I am very anxious
 to have, as it will I hope make me _proud_, as proud I shall be when
 I am able to pay everyone their demands, and have sufficient to carry
 on a little business to maintain my family and self without the
 assistance of others. May you succeed in your undertaking and also
 be independent, is the sincere wish of your friend. John Finnis and
 others are anxious to know when they will be wanted.

  "A. V."

The explosion at Greenwich in 1803 was made much of, though the
fault was clearly not in the boiler. Three years afterwards, in
1806, a steam-cylinder burst in Wales, therefore Mr. Williams, a
large shareholder in Dolcoath, objected to the use of high-pressure
expansive steam in their large Watt pumping engine, and desired their
engineer, Mr. Sims, to make a competitive trial after his own fashion.
At Condurrow Mine one of Trevithick's engines was to be ordered if the
Foxes and Williamses did not object; and so it was that Trevithick's
high-pressure steam-boiler was not ordered, and the Watt vacuum engine
was for a longer time to receive no increase of power.

 "Some of Captain Dick's early boilers had flattish or oval fire-tubes.
 In 1820 I repaired an old one in Wheal Clowance Mine in Gwinear. The
 flat top had come down a little; we put in a line of bolts, fastening
 the top of the tube to the outer casing.

 "About 1818 I saw in Carsize Mine in Gwinear a pumping engine that
 Captain Dick had put up. The boiler was a cylinder of cast iron, with
 a wrought-iron tube going through its length in which the fire was
 placed. The steam-cylinder was vertical, fixed in the boiler. She had
 an air-pump and worked with a four-way cock. The steam was about 100
 lbs. to the inch."[68]

 [Footnote 68: Banfield's recollections in 1869.]

 "About 1820 I removed one of Captain Trevithick's early high-pressure
 whim-engines from Creuver and Wheal Abraham, and put it as a pumping
 engine in Wheal Kitty, where it continued at work for about fifteen
 years. The boiler was of cast iron, in two lengths bolted together,
 about 6 feet in diameter and 10 feet long. At one end a piece was
 bolted, into which the cylinder was fixed, so that it had the steam
 and water around it. There was an internal wrought-iron tube that
 turned back again to the fire-door end, where the wrought-iron chimney
 was fixed; the fire-grate end of the tube was about 2 feet 6 inches
 in diameter, and tapered down to about 1 foot 6 inches at the chimney
 end. It was a puffer, working 60 lbs. of steam to the inch; it worked
 very well. There were several others in the county at that time
 something like it. It was made at the Neath Abbey Works in Wales."[69]

[Footnote 69: Recollections of Captain G. Eustace, engineer, residing at
Hayle, 1868.]

These boilers were of the kind first tried in Cornwall about 1800. The
oval tube in the Kensington model of 1798 continued in use in Cornwall
for many years. The cast-iron outer casing was soon abandoned, though
one of them in Wales remained in work fifty years, using steam of 60
lbs. to 100 lbs. to the inch.

  "MY DEAR JANE,

  "HAYLE FOUNDRY, _August 26th, 1810_.

 "I saw Captain Andrew Vivian on Wednesday, who told me that he had
 been offered 150_l._ a year to inspect all the engines in the county,
 and report what duty they were doing, in order to stimulate the
 engineers. He declined accepting it, having too much to do already;
 and he thought it would be worth Trevithick's notice, as it would not
 take him more than a day or two in a month.

  "I remain, my dear Jane,

  "Yours sincerely,

  "H. HARVEY.

 "I wrote this letter on Sunday, with an intention of sending it then,
 but thought it best to wait until this day, in hopes of hearing the
 determination of Government in your favour; but your letter has
 arrived without the desired information. All that I can now say is,
 to desire that Trevithick will make up his mind to return to Cornwall
 immediately.

  "H. H."


The application to the Government for remuneration for benefits
conferred on the public was unsuccessful. The office of registrar of
Cornish engines was unsuitable; fortunately for mining interests,
illness obliged Trevithick to revisit his native county, for by
the increased power and economy of his engines Dolcoath Mine, so
frequently mentioned, and so important in olden time, now returns
70,000_l._ worth of tin yearly.

Trevithick's first act on returning to Cornwall in 1810 was the
erection of the high-pressure boilers and pole vacuum engine at Wheal
Prosper; at the same time renewing his proposals to Dolcoath to use
his improved boilers, which had been broken off in 1806, and to apply
high-pressure steam to their low-pressure Watt engine, with the same
safety and profit as in Wheal Prosper; the evidence was undeniable,
so his plans were agreed to, and in the early part of 1811 the
high-pressure boilers, called the Trevithick or Cornish boilers, were
constructed in the Dolcoath Mine under his directions.

Old John Bryant, who worked the Dolcoath large engines both before and
after the introduction of higher pressure steam, including the Carloose
or Bullan Garden 45-inch cylinder engine, Wheal Gons 63-inch cylinder
single engine, and the Watt 63-inch cylinder double, with the bee-but
boiler, such as Trevithick, sen., used in 1775,[70] followed by the Watt
waggon boiler, and afterwards by the globular boiler of Trevithick,
jun., in 1799,[71] and still later also with the cylindrical boiler of
1811, gave the following statement, when seventy-four years old, to the
writer:--

[Footnote 70: See vol. i., p. 25.]

[Footnote 71: See vol ii., p. 119.]

 "In the old bee-but and the waggon boiler the steam pressure in the
 boiler was not much; we did not trouble about it so long as the
 engines kept going: when the steam was too high it blew off through
 the feed-cistern. When Captain Trevithick tried his high steam in
 Dolcoath we hoisted up the feed-cistern as high as we could; when
 the steam got up, it blew the water out of the cistern. Captain Dick
 holloed out, 'Why don't you trig down the clack?'

 "The cylindrical boilers when they were first put in leaked very
 much; we could hardly keep up the fire sometimes. I reckon the steam
 was 30 or 40 lbs. to the inch. Captain Dick's boilers made him lots
 of enemies. I heard say in one mine where he was trying his boilers
 against Boulton and Watt's waggon, a lot of gunpowder was put into the
 heap of coal."[72]

[Footnote 72: Old John Bryant's statement in 1858.]

The waggon or hearse Watt boiler was attached to his 63-inch cylinder
double, and the old man recollected having raised the water cistern,
when Trevithick's globe boiler gave an increased pressure in 1799, ten
or twelve years before the cylindrical boilers were made in Dolcoath.

 "Some time after Captain Dick's globe boiler and steam-whims had been
 at work in Dolcoath, a letter came down from London, saying that he
 would save the mine 100_l._ a month if they would put in one of his
 new plan boilers.

 "They were put in hand in the mine, and I worked about them; they were
 wrought-iron cylindrical boilers, about 20 feet long, and 5 or 6 feet
 in diameter; the fire-tube was about 3 feet in diameter; the fire
 returned around the outside in brick flues. Three boilers were put in
 side by side.

 "When Captain Dick first tried them, he said to the men, Now mind, the
 fire-bars must never have more than six inches of coal on them; give a
 shovel or two to one boiler, and then to another. When Captain Dick's
 back was turned, the men said they wasn't going to do anything of the
 sort, there would never be no rest for them. They used to say that the
 boilers saved more than 170l. the first month."[73]

[Footnote 73: Clark's recollections in 1869, when he was eighty-three
years old, and resided at Redruth.]

Clark, when a boy, in 1799, helped to construct Trevithick's globular
boiler in Dolcoath, and recollected the events of the few following
years, during the contests with the whim-engines about 1806, and the
introduction of the large cylindrical wrought-iron boilers for the
pumping engines in 1811, and the struggle preceding the downfall
of the Watt low-pressure steam vacuum engine, to make room for the
high-pressure expansive steam-engine, with or without vacuum.

 "About 1812 Captain Trevithick threw out the Boulton and Watt waggon
 boilers at Dolcoath and put in his own, known as Trevithick's boiler.
 They were about 30 feet long, 6 feet in diameter, with a tube about 3
 feet 6 inches in diameter going through its length. There was a space
 of about 6 inches between the bottom of the tube and the outer casing.
 Many persons opposed the new plans. The Boulton and Watt low-pressure
 engine did not work well with the high steam, and the water rose
 in the mine workings. Captain Trevithick, seeing that he was being
 swamped, received permission from the mine managers to dismiss the
 old engine hands and employ his own staff. Captain Jacob Thomas was
 the man chosen to put things right. He never left the mine until the
 engine worked better than ever before, and forked the water to the
 bottom of the mine. Before that time the average duty in the county by
 the Boulton and Watt engines was seventeen or eighteen millions, and
 in two or three years, with Trevithick's boilers and improvements in
 the engines, the duty rose to forty millions. About 1826 he (Captain
 Vivian) was manager of Wheal Towan; their engines were considered the
 best in the county, doing eighty-seven millions; they had Trevithick's
 boilers, working with high-pressure steam and expansive gear; few if
 any of Boulton and Watt's boilers could then be found in the county.
 Sir John Rennie and other scientific men, who doubted the reports of
 the duty, came and made their own trials with the engines, and were
 satisfied that the duty was correctly reported.

 "About that time a Mr. Neville requested him to report on the engines
 at his colliery at Llanelthy; one was an atmospheric of Newcomen's,
 doing six millions; and four or five of Boulton and Watt's patent
 engines averaged fourteen millions."[74]

[Footnote 74: Captain Nicholas Vivian was a schoolfellow and intimate
friend of Trevithick's; he resided at Camborne in 1858, when he gave
his recollections.]

When at last the cylindrical high-pressure boiler was admitted, and men
had been taught to fire them, many persons still liked the old plans,
and among them the easy-going low-pressure enginemen. The consequence
was that the Watt engines under their management refused the early
doses of Trevithick's high steam, not easily digesting it, and their
obstinacy nearly swamped Trevithick and his plans.

 "When a little boy, about 1812, I frequently carried my father's
 dinner from Penponds to Dolcoath Mine. One day, not finding him in the
 engine-house, I sought him in the account-house, but not knowing him
 in a miner's working dress, refused to give him his dinner. William
 West then worked with him. I heard there was difficulty in making the
 new boilers and the old engine work well; engineers from other mines
 looked on from a distance, not liking the risk of explosion. People
 seemed to be against the new plans; some labourers worked with them."

This narration--sixty years after the events--from Mr. Richard
Trevithick, the eldest son of the engineer, shows that William West
helped in applying high-pressure steam to the Watt low-pressure engine,
and that but few sympathized with the innovators on old customs; but
among them was Captain Jacob Thomas, who successfully fed the old
engine with strong steam.

At that time the Watt engines in Cornwall had been doing seventeen or
eighteen millions; Trevithick's new boilers increased their duty to
forty millions.

 "William Pooly[75] was working in Dolcoath before Captain Trevithick's
 new boilers were put in, and helped to put them in.

 [Footnote 75: William Pooly worked the Dolcoath 76-inch engine in 1869;
 his recollections were given in the old engine-house, on the spot once
 occupied by Watt and his 63-inch great double engine.]

 "The Shammal 45-inch engine was an open-top cylinder, with a chain to
 the segment-head wooden beam. So was the 63-inch cylinder Stray Park
 engine, then called Wheal Gons[76] in Dolcoath sett, and the Boulton
 and Watt 63-inch cylinder double-acting.

 [Footnote 76: Smiles speaks of this as Bonze's.]

 "There used to be great talking about different boilers; a boiler of
 Captain Trevithick's worked with higher steam than the others. Just
 before Captain Dick came back to the mine a Boulton and Watt hearse
 boiler had been repaired with a new bottom; it was never used. I and
 William Causan took a job to cut up the boiler at 1_s._ 6_d._ the
 hundredweight; it weighed 17 tons. Jeffrie and Gribble were the mine
 engineers; Glanville used to be considered Captain Dick's man in the
 mine. You could stand upright on the fire-bars in the middle hollow
 of the hearse boiler, and so you could in the outside brick flues;
 the middle hollow was like a horse-shoe. When Captain Dick put in his
 cylindrical boilers he altered the 63-inch single; there was hardly
 anything of her left but the main wall, with the wood bob and a chain
 to the piston-rod, and also to the pump-rods. There was an air-pump,
 and I think a second-hand cylinder was brought, but it was a 63-inch;
 the old Shammal engine had been altered, too.

 "The new boiler put in was about 8 feet in diameter and from 30 to
 40 feet long, two round tubes went through it; the fire-place in one
 end of one tube and in the other end of the other tube; after going
 through the tubes the draught went into the brick flues under the
 bottom and sides. When the new engine was put in, Gribble said, Why,
 these little things will never get steam enough; everybody said so.

 "In the Boulton and Watt engines we didn't trouble about feed-pumps
 and gauge-cocks.

 "A wire came through a stuffing box in the top of the boiler; a
 biggish stone in the boiler was fastened to one end of the wire, the
 other end was fastened to a weighted lever near the water cistern,
 just above the boiler; when the water got low the stone opened the
 valve in the water cistern. That was when they were putting in Captain
 Dick's new cylindrical boilers to the old 63-inch engine. She did so
 much more work, with less coal, that in a year or so they agreed to
 throw out Boulton and Watt's engine, and to put in a stronger one that
 could stand Captain Dick's high steam. Jeffrie and Gribble were the
 mine engineers that put her up. The 76-inch cylinder came from Wales.
 The big beam was cast at Perran Foundry in 1815; you can see the name
 and date upon it now. The boiler and the gear-work were made in the
 mine. The exhaust-valve is exactly as when it was put in, worked by
 a rack-and-tooth segment. The equilibrium valve is unchanged, except
 that the rack is taken out and a link put in.

 "The steam-valve was taken out soon after she went to work, and the
 present double-beat valve was put in; it is the first of the kind I
 ever saw. Some were made before that time with a small valve on the
 top of the big one, that opened first, to ease the pressure.

 "John West[77] fitted up the valve-gear in the mine with the expansive
 tappets, the same as when she stopped a month or two ago, and the same
 as the present new one has.

 [Footnote 77: Three Wests, all skilful mechanical engineers, were
 employed at that time in Dolcoath, all of them known to the writer,
 who thinks the double-beat valve was the handiwork of John West, not
 related to Trevithick's partner.]

 "Captain Dick's cutting off his strong steam at an early part of the
 stroke, used to make the steam-valve strike very hard; so the new
 plan valve, with a double beat, was put in; that must have been about
 1816 or 1817; and the valve and expansive horn for working were just
 exactly like what they have put into the present new engine in 1869.
 She was the engine that showed them how to fork the water, and burn
 only half the coal.

 "I worked in this mine the old atmospheric engines, and then Boulton
 and Watt; and then Trevithick's boilers in Boulton and Watt; and then
 Trevithick's boilers and engine; and now I come every day to the new
 engine, though I can't do much. They give me 35_s._ a month; and my
 name is William Pooly, Dolcoath, 1869."

Three years ago (in 1869), when the writer entered the old engine-house
in which Watt's 63-inch cylinder double had been erected in 1780,
adjoining the old walls that then enclosed that early Newcomen 45-inch
cylinder Carloose engine, re-erected by Trevithick, sen., in 1775 in
Bullan Garden portion of Dolcoath, an old man sat near a small window
in a recess in the thick wall of the engine-house, within reach of
the gear-handles of the Jeffrie and Gribble 76-inch cylinder engine
that Trevithick, jun., had erected in 1816 on the foundations of the
removed Watt engine; he held in one hand a portion of slate from the
roof, and in the other an old pocket-knife, one-half of the blade of
which had been broken off, leaving a jagged fracture, with which he
made the figures of some calculation on the rude slate; on his nose
rested the brass frame of a pair of very ancient spectacles, with horn
glasses. He answered the writer's question by, "Yes, I am William
Pooly; I worked this engine, and the other engines before it--the great
double and the little Shammal working out of the same shaft; and I am
seventy-four years of age. The 63 single worked upon a shaft up there;
she was called Wheal Gons." That old man, still living, had worked in
Dolcoath Mine one of the first steam-engines of Newcomen; the 45-inch,
modified by Trevithick, sen.; then the 63-inch double of Watt; and,
finally, the high-pressure engines of Trevithick, jun.; he saw the
open-top cylinders, atmospheric of Newcomen, in the Shammal 45-inch and
Wheal Gons 63-inch, with their wooden beams with segment-headed ends,
moving in rivalry with the Watt 63-inch double, with cylinder-cover
and parallel motion; he saw the two former engines, as altered by
Trevithick, jun., using the higher steam from the globular boiler on
which Henry Clark worked in 1799, when "there used to be great talking
about different boilers, and a boiler of Captain Trevithick's worked
with higher steam than the others; and the waggon boiler of Watt, that
had just been repaired, was discarded and cut up;" thus described by
Trevithick, "the fire-place is 22 feet from fire-door to fire-door, 9
feet wide, and 7 feet thick in fire,"[78] which he proposed to replace
in 1806 by a cylindrical boiler to give steam of 25 lbs. on the inch.

[Footnote 78: See Trevithick's letter, February 18th, 1806, vol. ii., p.
143.]

Pooly also saw the finishing stroke in 1811, when the boilers still
known as the Trevithick or Cornish boilers, gave steam to the three
engines; after a twelve years' fight between low and high pressure,
commencing with Trevithick's globular boiler and internal tube, in
Dolcoath, in the year 1799, from which time it gained step by step,
though in comparatively small engines, up to 1811, when the cylindrical
boilers took the place of the condemned hearse and globular boilers,
and gave really strong and expansive steam to the three Dolcoath
pumping engines that from time immemorial had been rivals, causing
all three of them to lift an increased quantity of water, and at the
same time to save one-half in the cost of coal; this continued for
four or five years, when in 1816 the 63-inch double and the 45-inch,
being the youngest and the oldest of the three, were removed, that a
new 76-inch cylinder, better adapted to Trevithick's expansive steam
might more cheaply perform their joint work. Prior to this change the
three engines were known by the names Shammal 45-inch, formerly Bullan
Garden,[79] but before that as Carloose, of the period and form of the
Pool engine;[80] Stray Park 63 single, formerly Wheal Gons,[81] dated
from 1770 to 1777; and the 63-inch double of Watt in 1780.

[Footnote 79: See vol. i., p. 25.]

[Footnote 80: See vol. i., p. 5.]

[Footnote 81: Query Bonze, spoken of by Smiles.]

  "SIR,

  "DOLCOATH MINE, _March 29th, 1858_.

 "I have obtained the following information respecting the building
 of the first cylindrical boilers, as ordered by your late father
 for Dolcoath; and some information of the results as to the coals
 consumed, compared with the consumption by the boilers previously in
 use here.

 "George Row, now about seventy-two years old, and working at Camborne
 Vean Mine, says he assisted to build the two first cylindrical boilers
 with internal tubes used in Cornwall. They were built in Dolcoath Mine
 in the year 1811; they were 18 feet long, 5 feet diameter, having an
 oval tube 3 feet 4 inches in the largest diameter at the fire end;
 the other or chimney end of the tube was somewhat smaller. They were
 found too small for the work to be done, and another boiler was built
 immediately, 22 feet long, 6 feet 2 inches diameter, and he believed a
 4-feet tube.

 "John Bryant, now seventy-four years old, works a steam-engine at
 West Wheal Francis. He worked at Dolcoath the 63-inch cylinder
 double-acting engine, upon Boulton and Watt's plan. When he first
 worked her she had the old bee-but boiler, 24 feet in diameter. They
 were taken out for the Boulton and Watt waggon boiler, 22 feet long
 and 8 feet wide, with two fire-doors opposite one another.

 "Then the Boulton and Watt waggon was taken out for Captain
 Trevithick's boilers, which he worked for several years. Two boilers
 were put in, each 18 feet long, 5 feet diameter, with an internal oval
 tube, he thinks, 3 feet by 2 feet 6 inches. Shortly after, another
 boiler of similar form was added, 22 feet long, 6 feet diameter,
 4-feet tube.

 "He cannot say what the saving of coal was, but remembers that the
 duty performed by the engine with the waggon boiler was thirteen to
 fourteen millions. Mr. William West came to the mine as an engineer,
 and by paying great attention increased the duty of the Boulton
 and Watt engine and boiler to about fifteen millions. He does not
 recollect the duty the engine performed with the cylindrical boilers.

 "Mr. Thomas Lean, of Praze, the present reporter of mine engines in
 the western part of Cornwall, in answer to a note I sent to him, says
 he has no account of any report of Dolcoath engines for the _year
 1812_, but during the month of April in that year the engines did
 21-1/2 millions. During the whole of 1813 that engine was reported to
 average a duty of twenty-one millions. The whole of the above are at
 per bushel of 93 lbs., and the whole of the accounts furnished by Mr.
 Lean are for Trevithick's cylindrical boilers.

 "From the Dolcoath Mine books I find the following: Paid for coals for
 the whole mine during the year 1811, 1150_l._ 15_s._ 10_d._, or per
 month, 931_l._ 14_s._ 7_d._ During the first three months of 1812 the
 coal averaged 1000_l._ per month. In May of this year, 1812, Captain
 Trevithick is entered on the books as paid 40_l._ on account of
 boilers; and in August of the same year, for erecting three boilers,
 105_l._ I think the three boilers were at work in April, 1812, the
 month Mr. Lean gives as the first reported. From April, 1812, to
 December, during nine months, the cost of coals was 5512_l._ 6_s._,
 averaging 612_l._ 9_s._ 6_d._ per month. During the next year, 1813,
 the cost for coal was 7019_l._ 17_s._ 5_d._, or an average per month
 of 590_l._ 16_s._ 5_d._ I cannot find the price paid per ton for the
 coal in these years, but the average price during 1808 and 1815 was
 much alike, making it probable that the price per ton during 1811,
 1812, and 1813, was nearly the same; and that the saving of the above
 300_l._ per month in Dolcoath was wholly on account of the saving
 effected by Trevithick's cylindrical boilers.

 "The testimony of John Bryant, that the duty with the waggon boiler
 was say fourteen millions, and that of Mr. Lean, giving twenty-one
 millions with the new Trevithick boiler, bear much the same proportion
 as the charges for coals in the respective periods above given.

 "In the year 1816 a new 76-inch single engine was erected in the place
 of the old Boulton and Watt 63-inch double engine with Trevithick's
 cylindrical boilers. The average duty performed during the year 1817
 was 43-3/4 millions. This same engine is still at work, and her
 regular duty is from thirty-six to thirty-eight millions.

  "I am, Sir,

  "Your most obedient servant,

  "CHARLES THOMAS.

 "FRANCIS TREVITHICK, Esq."

Captain Charles Thomas, who was one of the most experienced of Cornish
miners, for many years the manager of Dolcoath, and in youth the
acquaintance of Trevithick, states that the new high-pressure boilers
were made in the mine in 1811, and gave their first supplies of strong
steam to the three large pumping engines in April, 1812, with such good
effect that the increasing water which had threatened to drown the
mine was speedily removed, and that with a saving of nearly one-half
of the coal before consumed. Prior to their use Dolcoath Mine paid
1000_l._ monthly for coal; but for the latter nine months of the year,
in consequence of the new boilers, the cost was reduced to 612_l._ a
month. This saving in the pumping cost of one mine crowned with success
the high-pressure steam engineer, who had been steadily gaining ground
during his fight of twelve or fourteen years on the battle-ground
chosen by Watt thirty-three years before.

The low price of tin and copper, which caused so many engines to cease
working about the close of the last century, had changed for the
better, and the present century opened with an increasing demand for
steam power. Trevithick's high-pressure portable engines had worked
satisfactorily for several years; and as a means of making public the
relative duty performed by Cornish pumping engines, and of solving
conflicting statements on the rival systems of low and high pressure
steam, it was determined that an intelligent person should examine
and give printed monthly reports of the amount of duty done by the
different engines, and in 1810 Captain Andrew Vivian was requested
to take this work of engine reporter in hand; on his refusal it was
offered to Trevithick. In August, 1811, Mr. Lean commenced such monthly
reports, showing that the duty of twelve pumping engines at the end of
that year averaged seventeen millions, exactly the duty done by the
Boulton and Watt engines thirteen years before, as reported by Davies
Gilbert and Captain Jenkin in 1798, proving the small inherent vitality
of the Watt engine.

In 1814 the Dolcoath pumping engines, with Trevithick's cylindrical
boiler and high steam expansion, are thus reported:--"The Boulton
and Watt, Dolcoath great double engine, 63-inch cylinder, did a duty
of 21-1/2 millions; the Shammal 45-inch cylinder, single engine,
did 26-3/4 millions; and the 63-inch single, Stray Park engine, 32
millions." Shammal engine, nearly 100 years old, beat the Watt engine
of more than half a century later; and so did Stray Park 63-inch, which
Watt had laughed at when he first tried his hand as an engineer in
Cornwall in 1777.[82]

[Footnote 82: See vol. i., p. 30; vol. ii., p. 115.]

The marked change in these three engines, while for two or three years
under Trevithick's guidance, becoming more powerful and economical,
raised the usual swarm of detractors, and in 1815 a special trial was
made, which lasted for two days, to test the reported increased duty by
the cylindrical boilers and expansive working.

The unbelievers were then convinced, and agreed to throw out the
Boulton and Watt great double engine 63-inch cylinder, together with
its neighbour, the worn-out old 45-inch, and put in their stead one
engine with a cylinder of 76 inches in diameter, with expansive valve
and gear, and parts strong enough and suitable to the high-pressure
steam, on Trevithick's promise that it should do more than the combined
work of the other two with one-half the coal.

In 1816 this new engine commenced work, and did forty millions of
duty, increasing it during the next two or three years to forty-eight
millions, being three times the duty performed by the Watt 63-inch
double engine before it was supplied with steam from Trevithick's
boilers, and twice as much as it performed when so supplied. Lean
says, "This was the first instance of such duty having been performed
by an engine of that simple construction." The other mines followed
Trevithick's advice, but never paid him a penny. On this Lean again
says, "The engines at work in the county in 1835 would have consumed
80,000_l._ worth of coal over and above their actual consumption
yearly, but for the improvements that had been made since 1814."

Trevithick's engines were very durable, as well as cheap in first cost
and in working expense. This famous Dolcoath 76-inch engine remained
in constant work night and day for fifty-four years; after which good
service the steam-pipes, being thinned by rust, were held together by
bands and bolts; the steam-case around the cylinder would no longer
bear the pressure of steam; the interior of the cylinder from wear was
one inch larger in diameter than when first put in, and had to be held
together by strap-bolts. The original boilers were said to remain, only
they had been repaired until not an original plate remained; but there
they were in the old stoke-hole in 1869, when, from the fear of some
part of the engine breaking and causing accident, it was removed.

[Illustration: TREVITHICK'S DOLCOATH 76-INCH CYLINDER PUMPING
ENGINE, ERECTED IN 1816, CEASED WORKING 1869.

_a_, steam-cylinder, 76 inches in diameter, 9-feet stroke; _b_,
steam-jacket; _c_, steam expansion-valve, 11 inches diameter, double
beat; the upper beat 11 inches diameter, the under beat 9-1/2 inches,
valve 8 inches long; _d_, expansive cam on plug-rod; _e_, plug-rod
for moving the gear; _f_, expansive horn; _g_, equilibrium valve, 13
inches in diameter, single beat moved by a tooth-rack and segment; _h_,
exhaust-valve, 14-1/2 inches in diameter, single beat moved by a lever
and link; _i_, equilibrium-valve handle; _j_, exhaust-valve handle;
_k_, Y-posts for carrying the gear arbors; _l_, main beam in two plates
of cast iron; _m_, parallel motion; _n_, feed-pump rod; _o_, air-pump
bucket-rod, the pump, 2 feet 9 inches diameter; _p_, the main pump
rods.]

[Illustration: CYLINDER, MAIN BEAM, AND PUMP-ROD OF DOLCOATH
76-INCH CYLINDER ENGINE.]

In 1867 the writer was a member of the Dolcoath Managing Committee,
when it was determined that the old engine of 1816 should be replaced
by a new one. The cylinder sides were reduced in thickness by half an
inch; the steam-pipes and nozzles were thinned by rust and decay; the
valves and gear-work remained in good order. Captain Josiah Thomas, the
present manager of the mine, offered to sell this old engine at scrap
price, that it might be stored in the Patent Museum at Kensington as a
memento of the early high-pressure expansive steam pumping engine.

[Illustration: BOILERS ERECTED IN 1811 IN DOLCOATH, USED IN
THE BOULTON AND WATT 63-INCH ENGINE, THEN IN THE NEW 76-INCH UNTIL
1869.

_a a_, two wrought-iron cylindrical boilers, 5 feet in diameter, 18
feet long, with internal fire-tube, oval, 3 feet 4 inches by 3 feet;
_b_, a boiler, 6 feet 2 inches diameter, 22 feet long, cylindrical
tube, 4 feet diameter in the fire-place, the remainder 3 feet; _c_,
brick bridge; _d_, fire-bars; _e_, brick external flues under boiler;
_f_, brick side-flues; _g_, ashes, or other non-conductor; steam 30 to
50[**unclear] lbs. on the inch above the atmosphere.]

The steam-cylinder of 1816 was cast in South Wales; the beam still
working in the new engine of 1869 was cast in the foundry of the
Williams' at Perran. John West replaced the original flat expansive
steam-valve with a double-beat valve; the gear was principally made
by him on the mine, and remained in good working to the last. This
double-beat valve is the first the writer has met with; it is of the
same form as the modern double-beat valve; an earlier plan was to have
a small valve on the top of the main valve. The steam in ordinary
working was shut off when the piston had moved from an eighth to a
quarter of its stroke.

The Gons, or Stray Park 63-inch cylinder, survived its companions, the
63 double, and 45 single, for some ten or fifteen years, having beaten
both of them in duty. A memorandum in Trevithick's handwriting shows
that he in 1798, when designing his large globular boiler with internal
flue at the reworking of Dolcoath, tested the relative duty of the
Watt 63-inch double and the 63-inch single engine, then called Wheal
Gons, the latter in its original form of open-top cylinder atmospheric;
shortly after which it probably received a cover about the same time
as the 45-inch, for both those engines were thoroughly repaired by
Trevithick at the reworking of the mine, twelve or fourteen years prior
to the use of the cylindrical boilers.

 "At the time that Boulton and Watt made their trial of Seal-hole
 engine against Hornblower's engine at Tin Croft, the engines were put
 in the best order, and good coals brought in for the purpose, to work
 for twenty-four hours. The trial was attended by the principal mining
 agents; the result was about ten millions by each engine.

 "At Dolcoath Mine an old atmospheric engine continued to work for
 several years by the side of one of Boulton and Watt's engines of the
 same size; the water lifted and coals consumed were carefully taken
 and made known to the public, showing that Boulton and Watt's engine
 performed, when compared with the old engine, as 16 to 10."[83]

[Footnote 83: Memorandum in Trevithick's writing.]

Hornblower was an active engineer in Cornwall before Watt; the patent
of the latter claiming the sole right of working an engine by steam
in the cylinder,[84] drove the former to use two cylinders, in one
of which the expansion was carried out, as a means not described in
Watt's patent; a lawsuit was the consequence. The two engines when
tried by Trevithick[85] performed an equal duty of ten millions. In
1798 he tested the Dolcoath atmospheric 63-inch single against Watt's
great 63-inch double action. "The atmospheric performed ten millions,"
precisely the duty of the patent Watt and the patent Hornblower
contests of six years before; but the Watt Dolcoath engine, then
considered the best he had made, did sixteen millions. These trials in
1792 and 1798 enable us to compare the Newcomen, the Hornblower, and
the Watt engines; shortly after which Trevithick tried higher steam in
one or more of those same engines from his globular boiler.[86]

[Footnote 84: See vol. i., p. 46.]

[Footnote 85: See vol. i., p. 57.]

[Footnote 86: See vol. ii, p. 119.]

  "SIR CH. HAWKINS,        "CAMBORNE, _March 10th, 1812_.

 "Sir,--This day I shall attend the account at Wheal Prosper Mine, in
 Gwythian, to contract with the adventurers for erecting a steam-engine
 on my improved plan, for drawing the water 50 fathoms under the adit.
 I called on Wheal Liberty adventurers at St. Agnes last week, and
 found that several of them had given up their shares rather than put
 in a new engine, and the remainder of them very sick.

 "I told them that I would fork the water with the present engine, and
 draw instead of 40 gallons each stroke, 47 fathoms deep (which she
 did), 85 gallons per stroke, 65 fathoms deep, by altering the engine
 on the same principle as I have done with the Dolcoath great engine,
 and several more that are now altering. The expense of altering the
 engine, and forking the water to bottom, and proving the mine, will
 not exceed 1000_l._

 "All the adventurers are very anxious to again resume their shares and
 make the trial, on condition that I will undertake the completion of
 the job at a certain sum, but not otherwise.

 "I am certain, from what Dolcoath engine is doing, that I can far
 exceed the power above stated, and perform the duty with one-half
 the coal the engine consumed before, and would not hesitate a moment
 to engage the job on the terms they propose, but I have not money
 sufficient to carry it into execution, as I must lay out a large sum
 in erecting the engine on the Gwythian Mine, and unless I can be
 assisted with 500_l._, shall not be able to undertake the job.

 "If you think it worth your notice to encourage this undertaking by
 lending me the above sum for six months, I will pay you interest for
 it, and before drawing any part of it from you would get materials in
 the mine that should amount to above that sum, and also give you an
 order on the adventurers to repay you the whole sum before receiving
 any part myself.

 "As I have been a bankrupt, perhaps you may scruple on that account,
 but that business is finally settled, and I have my certificate; and
 indeed I never was in debt to any person; not one shilling of debt was
 proved against me under the commission, nothing more than the private
 debts of my swindling partner.

 "At Wendron we are working an engine lately erected on a copper lode,
 which has a very promising appearance, and near this spot you have
 land at Besperson, where there is also a very kindly copper lode,
 which deserves trial; if you are inclined to grant a sett, I think I
 can find adventurers to join me to try the mine.

 "I have lately read a letter from your hind, that the engine continues
 to mend; it far exceeds my expectation. I am now building a portable
 steam-whim, on the same plan, _to go itself_ from shaft to shaft; the
 whole weight will be about 30 cwt., and the power equal to twenty-six
 horses in twenty-four hours.

 "The only difference in this engine and yours will be the fire in the
 boiler, and without mason-work, on account of making it portable.
 I shall pass the rope from the fly-wheel round the cage of the
 horse-whim.

 "If you should fall in with any West India planter that stands in
 want of an engine, he may see this one at work in a month, which will
 prove to him the advantage of a portable engine, to travel from one
 plantation to another. The price, completely finished and set to work,
 free of all expense, in London, 105_l._

  "I am, Sir,
  "Your very humble servant,
  "RD. TREVITHICK.

 "N.B.--Captain John Stephens informed me, a few days since, that the
 lead mine at Newlyn was rich."

In Wheal Prosper Mine the first high-pressure expansive
steam-condensing pole-engine had been worked, just before the date of
the foregoing letter, and that evidence of increased power and economy
was immediately followed by the application of the same principles of
high-pressure steam and very expansive working to the Watt low-pressure
steam vacuum engines at Wheal Alfred, Dolcoath, and other mines,
with such satisfactory results as to warrant his offering, on the
battle-ground of his first attack on the Watt low-pressure steam vacuum
principle at Seal-hole in St. Agnes, fourteen years before,[87] at his
own pecuniary risk, to so apply those principles in the Wheal Liberty
low-pressure steam-engine, which had failed to drain the mine, lifting
only at the rate of 1880 gallons of water one fathom high at each
stroke; that it should lift an increased quantity of water, and that,
too, from an increased depth, making the load equal to 5525 gallons,
and to perform such increase of work with one-half of the quantity of
coal before used; in other words, he was willing to engage to make
the old low-pressure steam-engine perform by its conversion into a
high-pressure steam-engine threefold its original work, and also to
increase its duty or economic value sixfold; resting his argument on
the similar changes, then to be seen in operation at Wheal Alfred Mine,
and especially in the Watt 63-inch double-acting engine at Dolcoath,
whose history we have been tracing. Well might Sir Charles Hawkins
hesitate to believe what the experience of sixty years has barely
sufficed to make plain to us.

[Footnote 87: See vol. i., p. 90.]

  "CAPTN. TREVITHICK,        "PENZANCE, _March 27th, 1813_.

 "Sir,--In consequence of the conversation that has passed between
 you and West Wheal Tin Croft adventurers, the said adventurers have
 resolved to put an engine on that mine, agreeable to the proposals
 offered by you; that is, the engine shall be capable of lifting a
 5-inch bucket, 50 fathoms, 4-feet stroke, 15 strokes per minute,
 or a duty equal thereto; for which they will pay you 50 guineas one
 month after the engine shall be at work, and 50 guineas more at four
 months after that, and 50 guineas more at four months from that time,
 making the full payment of 150 guineas in nine months from the time
 the engine shall set at work, the adventurers paying all expense,
 except the engine materials, which shall be delivered on the mine. But
 in case the engine not performing the above duty, the adventurers to
 be at liberty to return the same engine, and you to pay back all the
 money that you had received for the said engine.

  "Signed by GABL. BLEWETT,
  "in behalf of the Adventurers and Company."

Trevithick was willing to spend more than his last penny in
establishing the superiority of his high-pressure steam expansive
engines, but the selfishness of adventurers retarded their progress.
The atmospheric, mentioned by Watt as working in Dolcoath in 1777,[88]
did five or six millions of duty, yet in Trevithick's hands, about 1798
to 1800, when he erected his globular boiler with internal tube, one
of them was tested with the 63-inch Watt low-pressure vacuum engine,
when the latter did sixteen millions to ten millions by the atmospheric
engine, being nearly double the duty it performed in its original form;
and we shall still trace this same engine as Bonze or Gons until it
increased to six times its first duty under the name of Stray Park
63-inch.

[Footnote 88: See vol. i., pp. 30, 57; vol. ii., p. 115.]

Trevithick having erected a high-pressure steam condensing whim-engine
at Cook's Kitchen,[89] and in Dolcoath[90] a high-pressure puffer
whim-engine, pleaded hard in 1806[91] to be allowed to supply the large
pumping engines of Newcomen and Watt with higher pressure steam from
his cylindrical boiler, which after years of consideration Dolcoath, in
1811, agreed to. In 1813 he wrote:--"That new engine you saw near the
sea-side with me is now lifting forty millions, one foot high, with one
bushel of coal, which is very nearly double the duty that is done by
any other engine in the county. A few days since I altered a 64-inch
cylinder engine at Wheal Alfred to the same plan, and I think she will
do equally as much duty. I have a notice to attend a mine meeting to
erect a new engine, equal in power to a 63-inch cylinder single."[92]

[Footnote 89: See vol. i., p. 91.]

[Footnote 90: See vol. i., p. 91.]

[Footnote 91: See vol. ii., p. 142.]

[Footnote 92: See Trevithick's letter, January 26th, 1813, vol. ii., p.
55.]

The beneficial results of those acts are too large to be here
entered into in detail. In round numbers, the early pumping engines
of Newcomen did five millions;[93] Trevithick caused them to do ten
millions of duty with a bushel of coal. Watt, during thirty years of
improvements, caused the duty to reach sixteen or twenty millions in
1800. Trevithick, on the expiry of the Watt patent, then came into
play, and before he had reigned half the time of Watt, again doubled
the duty of the steam-engine, as he states in 1813 "his new engine was
doing forty millions, being nearly double the duty of any other engine
in the county." These statements by Trevithick agree very nearly with
the generally-received accounts of the progressive duty of the large
pumping steam-engine.

[Footnote 93: See vol. i., p. 41.]

 "In 1798 Davies Gilbert, Esq., and the late Captain Jenkin of
 Treworgie, found the average of the Boulton and Watt engines in
 Cornwall to be about seventeen millions. In August, 1811, the eight
 engines reported averaged 15·7 millions. During the year 1814 Dolcoath
 great engine, with a cylinder of 63 inches in diameter, did twenty-one
 and a half millions nearly. Dolcoath Shammal engine, with a cylinder
 of 45 inches in diameter, did twenty-six and three-quarter millions.
 Dolcoath Stray Park engine, with a cylinder of 63 inches in diameter,
 did thirty-two millions.

 "In 1815 a trial was made, to prove the correctness of the monthly
 reports. Stray Park engine at Dolcoath was chosen for the purpose,
 because its reported duty was such as led some persons to entertain
 doubts of its accuracy. The trial was continued for ten days, to the
 full satisfaction of all concerned.

 "In 1816, Jeffrie and Gribble erected a new engine, 76-inch cylinder,
 single, at Dolcoath, which did forty millions. This was the first
 instance of such duty having been performed by an engine of that
 simple construction.

 "In 1819, Dolcoath engine performed the best during this year, and at
 one time reached forty-eight millions.

 "In 1820, Treskerby engine, to which Trevithick's high-pressure pole
 had been adapted, reached 40·3 millions.

 "In 1816, Sims also erected an engine at Wheal Chance, to which he
 applied the pole adopted by Trevithick in his high-pressure engines.
 This engine attained to forty-five millions.

 "In 1828 public attention had now been attracted to the improvements
 which Captain Grose had introduced into his engine at Wheal Towan.
 The duty of this engine, in the month of April this year, equalled
 eighty-seven millions.

 "This again gave rise to suspicions of error in the returns. This
 engine was accordingly subjected to a trial (as Stray Park engine had
 been in 1815), which was superintended and conducted by many of the
 principal mine agents, engineers, and pitmen of other mines.

 "The quantity of coal consumed in 1835, compared with the quantity
 that would have been consumed by the same engines in the same time,
 had they remained unimproved from the year 1814, shows that the saving
 to the county amounts to 100,000 tons of coal, or 80,000_l._ sterling
 per annum."[94]

[Footnote 94: Lean's 'Steam-Engine in Cornwall.']

Lean seems to have calculated on a bushel of coal as 94 lbs. In 1798,
when Trevithick was about to give increased pressure of steam to the
Cornish engines, his friend Davies Gilbert reported the average duty of
the Watt engine in Cornwall to be seventeen millions.

In August, 1811, the reported duty averaged 15·7 millions. This was
the month and year in which Trevithick, after twelve years of working
evidences of the reasonableness of his promises of increased power
and economy from using high-pressure steam, was allowed to erect his
cylindrical boilers for the large pumping engines in Dolcoath Mine.

Has the reader realized that the 45-inch atmospheric Carloose engine,
of nearly 100 years before,[95] had in 1775[96] become the Bullan Garden
engine of Trevithick, sen., which was improved and re-erected by
Trevithick, jun., in 1799,[97] when the name was again changed, this
time to Shammal, because it was linked to another engine, no other than
the Watt 63-inch double engine? This Shammal 45-inch took steam from
the globular boiler, using a pole air-pump[98] and a Watt condenser,
though retaining the beam with the arched head and chain connection;
and again in 1811 took still more highly expansive steam from the
cylindrical boilers with a new beam and parallel motion, enabling it in
1814 to beat its rival, the Watt Dolcoath great double engine.[99] The
old 63-inch Gons, under the name of Dolcoath Stray Park engine, with
Trevithick's improvements, did sixty-seven per cent. more work than the
Watt 63-inch with an equal quantity of coal.

[Footnote 95: See vol. i., p. 21.]

[Footnote 96: See vol. i., p. 25.]

[Footnote 97: See vol. ii., p. 120.]

[Footnote 98: See vol. ii., p. 122.]

[Footnote 99: See Lean's report, vol. ii., p. 175.]

This startling fact was disbelieved by the advocates of low-pressure
steam, and as the visible change in the Dolcoath engine from Newcomen
to Watt, and from Watt to Trevithick, had been gradual and not very
striking, and the public were careless of principles, the one most
puffed was most thought of; but the money saved was tangible, and in
1815 a special trial was made, which lasted two days, to discover if it
was really true that Trevithick's appliances could so increase the duty
of the engine. The 63-inch cylinder, then called Stray Park engine,
was selected; the result proved that the large saving reported from
Trevithick's boilers and expansive working during the last three or
four years, was an incontrovertible fact.

The high-pressure steam was also given to the defeated Watt 63-inch
double engine; yet this newest of the three engines was the first to be
condemned, and her place was taken in 1816 by an engine of 76 inches in
diameter, which Trevithick promised should, with his high steam and new
expansive gear, do the work of the Watt 63-inch and the old 45-inch put
together; which was more than fulfilled by its doing forty millions,
and, as Lean says, "was the first instance of such duty having been
performed by an engine of that simple construction."

In 1819 the new 76-inch engine which had been erected by the mine
engineers, Jeffrie[100] and Gribble, who had long been employed by
Trevithick in Dolcoath, was the best in the county, doing forty-eight
millions, nearly three times the duty as given by Mr. Gilbert for the
Watt engine in 1798. In 1827 Trevithick's pupil, Captain Samuel Grose,
erected his Wheal Towan engine, which performed a duty of eighty-seven
millions, some of the working drawings of which were made by the
writer. In 1835 the principle laid down by Trevithick had become so
general in the county as to cause a saving to the Cornish mines, in
coal alone, of 80,000_l._ yearly. In addition to this, the increased
power of the engine lessened the first cost by at least one-half.

[Footnote 100: See vol. i., p. 106.]

The national importance of such weighty facts calls for further
corroborative proof, for we can scarcely believe that two atmospheric
low-pressure steam-engines, made before the time of Watt, could be
altered so as to perform more work, and at a less cost than the
Watt engine, by an ingenious supply of higher steam pressure from
Trevithick's boilers, together with the Watt air-pump and condenser.
The following words from Watt are descriptive of his practice, though
contrary to his patent claim:--

 "At a very early period, while experimenting at Kinneil, he had formed
 the idea of working steam expansively, and altered his model from
 time to time with that object. Boulton had taken up and continued the
 experiments at Soho, believing the principle to be sound, and that
 great economy would attend its adoption.

 "The early engines were accordingly made so that the steam might be
 cut off before the piston had made its full stroke, and expand within
 the cylinder, the heat outside it being maintained by the expedient of
 the steam-case. But it was shortly found that this method of working
 was beyond the capacity of the average enginemen of that day, and it
 was consequently given up for a time.

 "'We used to send out,' said Watt to Robert Hart, 'a cylinder of
 double the size wanted, and cut off the steam at half-stroke.'

 "This was a great saving of steam, so long as the valves remained as
 at first; but when our men left her to the charge of the person who
 was to keep her, he began to make, or try to make, improvements, often
 by giving more steam. The engine did more work while the steam lasted,
 but the boiler could not keep up the demand. Then complaints came of
 want of steam, and we had to send a man down to see what was wrong.

 "This was so expensive, that we resolved to give up the expansion of
 the steam until we could get men that could work it, as a few tons of
 coal per year was less expensive than having the work stopped. In some
 of the mines a few hours' stoppage was a serious matter, as it would
 cost the proprietor as much as 70l. per hour."[101]

[Footnote 101: Smiles' 'Lives of Boulton and Watt,' p. 228.]

Pole expresses the same view, intimating that Watt only used steam of 1
or 2 lbs. pressure to the inch.

 "In Watt's engine, as is well known, the pressure of steam in the
 boiler very little exceeded the pressure of the atmosphere. He
 recommended that when the engine was underloaded, this excess should
 be equal to about 1 inch of mercury; and when full loaded, ought not
 to exceed 2 inches; adding, 'It is never advisable to work with a
 strong steam when it can be avoided, as it increases the leakages of
 the boiler and joints of the steam-case, and answers no good end.'[102]

 [Footnote 102: Appendix A to Tredgold, 'Pole on Cornish Engines,' p. 49.]

 "Mr. Watt's engines with such boilers" (which will not retain steam of
 more than 3-1/6 lbs. per square inch above the atmosphere) "cannot be
 made to exert a competent power to drain deep mines, unless the supply
 of steam to the cylinder is continued until the piston has run through
 more than half its course.[103]

 [Footnote 103: 'Phil. Mag. and Annals,' N.S., vol. viii., p.
 309, by W. J. Henwood.]

 "In 1801-2 Captain Trevithick erected a high-pressure engine of small
 size at Marazion, which was worked by steam of at least 30 lbs. on
 the square inch above atmospheric pressure. In 1804, as Mr. Farey
 admits,[104] the same gentleman introduced his celebrated and valuable
 wrought-iron cylindrical boilers,[105] now universally used in this
 county.

 [Footnote 104: Ibid., p. 313.]

 [Footnote 105: Ibid., vol. i., p. 127.]

 "To these, everyone at all acquainted with the Cornish improvements
 ascribes a great part of the saving we have obtained. This will
 farther appear from an extract from a valuable work edited by John
 Taylor, Esq., F.R.S.[106]

 [Footnote 106: 'Records of Mining,' p. 163.]

 "The monthly consumption of coal in Dolcoath Mine was, in 1811, 6912
 bushels; in 1812, 4752 bushels.[107] The alteration in the boilers was
 the introduction of Captain Trevithick's cylindrical boilers in the
 place of the common waggon boilers, which had until then been there in
 use.

 [Footnote 107: Alteration in the boilers that year.]

 "Mr. Woolf, as Mr. Farey states, came to reside in Cornwall about the
 year 1813, and his 'first engines for pumping water from mines were
 set up by him in 1814.'"[108]

[Footnote 108: 'Phil. Mag. and Annals,' vol. x., p. 97, "Notes on Some
Recent Improvements of the Steam-Engine in Cornwall," by W. Jory
Henwood, F.G.S.]

The foregoing was read at the Philosophical Society in 1831, to refute
erroneous statements on the Watt and Trevithick engines. My friend
Mr. Henwood had at that time made official experiments in conjunction
with Mr. John Rennie on the detail, working, and duty of high-pressure
steam Cornish engines, the Watt low-pressure steam principle having
been wholly given up. Rees's 'Cyclopædia'[109] also bears the following
similar testimony to date of the increased duty:--

[Footnote 109: See Rees 'On the Steam-Engine,' published 1819.]

 "Trevithick's high-pressure engine was erected in Wales in 1804 to
 ascertain its powers to raise water. The duty was seventeen millions
 and a half pounds raised one foot high for each bushel of coals.

 "The high-pressure steam-engines require a greater quantity of coals,
 in proportion to the force exerted, than the engine of Mr. Watt, and
 consequently are not worked with advantage in a situation where coals
 are dear.

 "From the reports of the engines now working in the mines of Cornwall,
 which, with the exception of a few of Woolf's engines, are all on Mr.
 Watt's principle, and most of them constructed by Messrs. Boulton and
 Watt, taking the average of nine engines--bad, good, and indifferent
 together--they were found in August, 1811, to raise only thirteen
 millions and a half. But when it was known by the engine keepers
 that their engines were under examination, they took so much pains
 to improve the effects, that by gradual increase the engines in
 1815 lifted twenty-one millions and a half, taking the average of
 thirty-three engines. In 1816, Stray Park, a 63-inch cylinder, 7 feet
 9 inches stroke, single-acting, being one of the three engines on
 the vast Dolcoath Mine; its performance in four different months was
 thirty-one, thirty-one and a quarter, twenty-eight, and twenty-eight
 and a half millions."

This statement reveals a source of error in estimating the relative
values of the Watt and the Trevithick engine; that of the latter was
the Welsh locomotive, compared in duty with the large Watt pumping
engine, pointed out in Trevithick's letter[110] of that time, as an
unfair comparison; the small high-pressure puffer, in 1804, is admitted
to have done seventeen and a half millions of duty with a bushel of
coal of 84 lbs., while in Rees' calculation of the engines, he gives
Watt 94 lbs. of coal to a bushel; and having stated that the Watt
pumping engines in Cornwall, in 1811, averaged but thirteen and a half
millions of duty, draws the false conclusion that the high-pressure
cannot compete with the low-pressure where coals are dear; yet he
agrees with other writers that the great increase in the duty of the
Cornish pumping engines commenced from 1811 (when Trevithick first
gave them his high-pressure steam); and states that in 1816 the Stray
Park 63-inch cylinder single-acting engine,[111] being one of three then
working in Dolcoath, did thirty-one millions.

[Footnote 110: See vol. i., p. 166.]

[Footnote 111: See Watt's statement, vol. ii., p. 115.]

The 'Encyclopædia Britannica' on the question of duty states:[112]--

[Footnote 112: See "Steam-Engine," published 1860.]

 "The duty of the best of Smeaton's engines was, in 1772, 9,450,000
 foot pounds per cwt. of coal. On the expiration of Watt's patent,
 about the year 1800, the highest duty of his engines amounted to
 twenty millions, or more than double the former duty, which may
 represent the economical value of the improvement effected by Watt
 under his various patents.

 "The reported duty of Cornish pumping engines, by the consumption of
 94 lbs. of coals, rose from an average of nineteen millions and a
 half, and a maximum of twenty-six millions in 1813, to an average of
 sixty millions and a maximum of ninety-six millions in 1843. It is
 necessary to bear in mind the distinction between the duty of a bushel
 of coal and 112 lbs."

Here, also, are the same general facts as to the duty of the Watt
engine, and the marked and rapid increase of duty dating from
Trevithick's Dolcoath engines in 1811; but the confusion and even
contradictions in the statements prove how little the subject was
understood.

 "A rough draft, prepared by Mr. Edmonds on Trevithick's return from
 America, dated 1828, for an application to Parliament for remuneration
 to Trevithick, says, 'That this kingdom is indebted to your petitioner
 for some of the most important improvements that have been made in the
 steam-engine.

 "'That the duty performed by Messrs. Boulton and Watt's improved
 steam-engines in 1798, as appears by a statement made by Davies
 Gilbert, Esq., and other gentlemen associated for that purpose,
 averaged only fourteen millions and a half (pounds of water lifted 1
 foot high by 1 bushel of coal), although a chosen engine of theirs
 under the most favourable circumstances lifted twenty-seven millions,
 which was the greatest duty ever performed till your petitioner's
 improvements were adopted, since which the greatest duty ever
 performed has been sixty-seven millions, being much more than double
 the former duty. That, prior to the invention of your petitioner's
 boiler, the most striking defect observable in every steam-engine was
 in the form of the boiler, which in shape resembled a tilted waggon,
 the fire being applied under it, and the whole being surrounded with
 mason work. That such shaped boilers were incapable of supporting
 steam of a high pressure or temperature, and did not admit so much of
 the water to the action of the fire as your petitioner's boiler does,
 and were also in other respects attended with many disadvantages.
 That your petitioner's invention consists principally in introducing
 the fire into the midst of the boiler, and in making the boiler of a
 cylindrical form, which is the form best adapted for sustaining the
 pressure of high steam.

 "'That the following very important advantages are derived from this
 your petitioner's invention. This boiler does not require half of the
 materials, nor does it occupy half the space required for any other
 boiler. No mason work is necessary to encircle the boiler.[**'"]

 "'That, had it not been for this your petitioner's invention, those
 late vast improvements which have been made in the use of steam
 could not have taken place, inasmuch as none of the old boilers
 could have withstood a pressure of above 6 lbs. to the inch beyond
 the atmosphere, much less a pressure of 60 lbs. to the inch, and is
 capable of standing a pressure of above 150 lbs. to the inch.'"

Trevithick's retrospect views of 1828 are supported by the letter of
the late Michael Williams, M.P., the most experienced of Cornish mine
workers, but belonging to the eastern district that had been for many
years the users of the Watt engines in Cornwall.

 "In reference to his great improvements in the steam-engine, I have a
 more particular recollection, and can confidently affirm that he was
 the first to introduce the high-pressure principle of working, thus
 establishing a way to the present high state of efficiency of the
 steam-engine, and forming a new era in the history of steam power. To
 the use of high-pressure steam, in conjunction with the cylindrical
 boilers, also invented by Mr. Trevithick, I have no hesitation in
 saying that the greatly-increased duty of our Cornish pumping engines,
 since the time of Watt, is mainly owing; and when it is recollected
 that the working power now attained amounts to double or treble that
 of the old Boulton and Watt engine, it will be at once seen that it is
 impossible to overestimate the benefit conferred, either directly or
 indirectly, by the late Mr. Trevithick on the mines of this county.
 I have often expressed my opinion that he was at the same time the
 greatest and the worst-used man in the county."[113]

[Footnote 113: See letter of Michael Williams, chap. xix.]

The late Sir John Rennie and other scientific persons were, about 1830,
associated with Mr. Henwood[114] in examining the work performed by
Cornish pumping engines: their reports are curtailed in the following
comments on Wheal Towan engine, similar to Trevithick's Dolcoath engine
of 1816, except perhaps that the last named was a little inferior
in its detail movements, while much less care was taken to avoid
unnecessary loss of heat.

[Footnote 114: Henwood, 'Edinburgh Journal of Science,' 10.]

[Illustration: STEAM DIAGRAM OF WHEAL TOWAN PUMPING ENGINE, ERECTED
1827.]

Mr. Henwood also gave indicator diagrams of the expansion of the steam,
on one of which the writer has marked ten horizontal lines, indicating
the position of the piston at each foot of its stroke, and ten
longitudinal lines dividing the diameter of the cylinder into tenths.
The steam pressure in the boiler was 46·8 lbs. on the square inch
above the atmosphere, or 4·68 lbs. for each of the ten longitudinal
line divisions. _x_ to _c_ represents the top of the steam-cylinder 80
inches, diameter; _x_ to F the length of the cylinder for a 10-feet
stroke of the piston. By the time the piston had moved through
one-twentieth of its course, reaching _c_, the expansive working had
commenced; and when one-tenth of the stroke had been run, half of a
division was cut off, showing by the curved indicator line the decrease
in pressure of steam to 44.46 lbs. The comparatively small passage
through the steam-valve not giving room for sufficient steam to follow
up the increasing speed of the piston, led to its continued expansion
in the cylinder, and by the time the piston had moved 2 feet, reaching
D, the steam pressure was reduced by two divisions or 9.36 lbs., or a
pressure of 37.44 lbs. on the piston; at this point the steam-valve was
closed, and the remaining four-fifths of the stroke was performed by
expansion; at the fifth horizontal line, or middle of the stroke, only
three divisions of steam are left, giving a pressure of 14.04 lbs. to
the inch; at the finish of the stroke there is only half a division,
from E to F, or 2.34 lbs. of steam to the inch above the pressure of
the atmosphere. On the return up-stroke of the piston, when it had
reached within a foot of the finish of its course at C, the equilibrium
valve closed, causing the enclosed steam of 2.34 lbs. to the inch to
be compressed at the finish of the up-stroke shown by the curve G A to
9.36 lbs. on the inch, equal to its pressure about the middle of the
down-stroke at N.

Trevithick's expansive engine therefore, commencing its work with
steam of 46.8 lbs. on the inch above the atmosphere, only took a full
supply from the boiler during one-tenth of its stroke, and none after
one-fifth had been performed, while at the finish of the stroke it had
about the same pressure as Watt began with.

The _power_ of the Watt low-pressure steam vacuum pumping engine was
increased by Trevithick from two to three fold, and its economical
duty in about the same proportion; in other words, he increased
the effective power of the steam-engine two or three fold without
additional consumption of coal.

In the Wheal Towan engine the steam-cylinder was 80 inches in diameter,
with a 10-feet stroke. The shaft was 900 feet in depth; the main pumps
16 inches in diameter; the pump-rods were of wood, about 14 inches
square, and weighed more than the column of water in the pipes. The
boilers were Trevithick's cylindrical with internal tube, wholly of
wrought iron. The cylinder and steam-pipes were surrounded with sawdust
about 20 inches in thickness, as a non-conductor of heat. The upper
surfaces of the boilers were covered with a layer of ashes for the same
purpose. The duty performed was 86·58 millions of pounds of water,
raised one foot high by the consumption of a bushel of coal weighing 84
lbs. The immense power and economy of this engine are best understood
by its average labour costing only one farthing in coal for lifting
1000 tons one foot high.

At or about that time an old intimate of Trevithick's, Captain Nicholas
Vivian, managed the mine, and Mr. Neville, a shareholder, also a
user of steam-engines in Wales, observing the economical working of
Wheal Towan high-pressure steam expansive engine, doing eighty-seven
millions, requested its manager to examine colliery engines, all
of which were of the low-pressure kind; one of them was a Newcomen
atmospheric, whose duty was six millions; four or five others were Watt
low-pressure steam vacuum engines, doing fourteen millions; therefore
the high-pressure steam-engine did six times as much work with a bucket
of coal as the low-pressure steam vacuum, and fourteen times as much as
the low-pressure steam atmospheric engine. Several competitive trials
by the county engineers were published about that time, in one of
which, after a personal examination of the engine, Mr. W. J. Henwood[115]
and others reported a duty of 92·6 millions with a 91-lb. bushel of
coal.[116]

[Footnote 115: Address, Royal Institution of Cornwall, by W. J. Henwood,
1871.]

[Footnote 116: Trevithick calculated 84 lbs. to a bushel; Watt generally
112 lbs.; Lean 94 lbs., but latterly 112 lbs.]

Mr. Rennie had been a pupil, a fellow-worker with low-pressure Watt,
and while his son, Sir John Rennie, was examining the high-pressure
steam expansive engine erected by Trevithick's pupil, Captain Samuel
Grose, under the management of Trevithick's friend, Captain Nicholas
Vivian, the latter was engaged in reporting on certain low-pressure
steam-engines in Wales, one of which was a Newcomen's atmospheric,
probably the last of its race, whose principle of construction was a
century old, working in company with the Watt low-pressure steam vacuum
engine, then half a century old, the principles of both systems being
on their last legs, and under the care of Trevithick's supporters.

During this jumble of engines, old and new, without a clear
comprehension of their differences in principle, Trevithick, who had
just returned from America, and lived within a few miles of Wheal
Towan, looked on unconsulted and unconcerned on questions which in
his mind had been settled by him in Dolcoath fifteen or twenty years
before. The writer, during the Wheal Towan controversy, was the daily
companion of Trevithick, and made drawings of the engine at the works
of Harvey and Co., of Hayle, where it was constructed about 1827.

Captain Samuel Grose's Wheal Towan engine was in general character
similar to his teacher's Dolcoath 76-inch engine of 1816, working with
about the same steam pressure and degree of expansion. The valves,
gear, and nozzles were perhaps improved in detail; but the groundwork
was unchanged. The first high-pressure steam Cornish pumping engine
made in France was designed and superintended by the writer at the
works of Messrs. Perrier, Edwards, and Chaper, at Pompe-à-feu, in
Chaillot, a suburb of Paris. The principle was the same as the Dolcoath
engine, and the detail differed but little from it or the Wheal
Towan, except that its exterior was a little more artistic than its
prototypes in Cornwall, in keeping with French requirements. It was
built in 1836, within a few yards of the low-pressure steam pumping
engine erected by Perrier and others in 1779, which still continued
pumping water from the Seine for the supply of Paris. Stuart says,
"An engine by Boulton and Watt was sent to France, and erected by M.
Perrier at Chaillot, near Paris. The French engineer, Proney, with a
detestable illiberality, attributes all the merit of the improvements
in the Chaillot engine to his friend Perrier, the person who merely put
together the pieces he had brought from Soho."[117]

[Footnote 117: Stuart 'On the Steam-Engine,' p. 141.]

The Perrier of 1779 was related to the Perrier of the Pompe-à-feu
engine-building works of 1836, and his nephew took the Trevithick
engine from Paris to a coal mine not far from Brussels, but not fully
understanding the use of the balance-bob--the woodwork for which had
not been completed in Paris, though all other parts had been fully
erected--did not find it easy to manage the engine. The writer viewed
Perrier's move as an infringement of the agreement between him and
Edwards, the partner of Perrier and Chaper, and therefore declined to
take any further interest in the engine.

Mr. Edwards had before that been a partner with Woolf, in a small
engineering works in Lambeth; and the writer had also before that been
a pupil of Woolf's, in the works of Messrs. Harvey and Co., of Hayle.

The drawing of 'La Belle Machine' (Plate XIII.), of 1836, serves not
only as a record of that time, but also in conjunction with the drawing
of Dolcoath engine of 1816, enables an engineer to form a sufficiently
correct idea of the Wheal Towan engine and boilers of 1827, which in
effective duty is scarcely excelled by the best pumping engines of the
present day.

The events connected with those Paris engines bring together the
engineering works of Watt, Proney, Perrier, Trevithick, and Woolf, in
the person of his once partner, Edwards. The writer, when constructing
'La Belle Machine,' had not the slightest knowledge of those links, and
heard the name and repute of his engine by the following chance:--

In 1838 a passenger leaving the train of the Great Western Railway
at Drayton Station, asked the writer's permission to walk on the
line and examine its construction. During a short conversation he
mentioned the having purchased at a sale in France the drawings of
an engine known as 'La Belle Machine,' representing the Cornish
high-pressure expansive steam pumping engine:--_a_, steam-cylinder, 48
inches in diameter, 8-feet stroke; _b_, steam-pipe from boiler; _c_,
regulating steam-valve, double beat; _d_, regulating rod and handle for
steam-valve; _e_, expansive steam-valve, double beat; _f_, balanced
lever and rod for opening expansive valve; _g_, expansive clamp on
plug-rod, with regulating rod and thumb-screws; _h_, cataract-rod for
relieving expansive valve-catch; _i_, quadrant relieving the catch;
_j_, plug-rod; _k_, equilibrium valve, double beat; _l_, clamp in
plug-rod to close equilibrium valve by its action on the handle; _m_,
balanced lever and rod to open equilibrium valve; _n_, quadrant and
catch relieving equilibrium valve by the action of cataract-rod; _o_,
regulating slide on cataract-rod; _p_, equilibrium steam-pipe conveying
steam from the top to the bottom of the piston; _q_, exhaust-valve,
double beat; _r_, clamp on plug-rod, closing the exhaust-valve by
its descent on the handle; _s_, balance lever and rod, opening
exhaust-valve; _t_, quadrant and catch, relieving equilibrium valve
by the action of cataract-rod; _u_, regulating slide on cataract-rod;
_v_, exhaust-pipe to condenser; _w_, Y-posts for carrying the gear.
The steam in the boiler was from 40 lbs. to 50 lbs. on the square inch
above the atmosphere.

[Illustration: PLATE 13.

LA BELLE MACHINE. HIGH PRESSURE STEAM EXPANSION PUMPING ENGINE.--1836.

London: E.& F N. Span. 48, Charing Cross. Kell. Bro^s. Lith. London.]

Lean states that had the pumping engines at work in Cornwall in 1835
remained unimproved since 1814, at which time they had benefited by
three years of continuous improvement, a yearly additional expenditure
of 80,000_l._ for coal would have been the consequence, and that the
first step was Trevithick's expansive steam from the cylindrical
tubular boiler, engines using such steam performing a duty three or
four fold what Boulton and Watt had ever attained, or perhaps thought
possible of attainment.[118] The birth of the idea of using expansive
steam may in truth be traced back nearly one hundred years to the time
of Newcomen's atmospheric engine, and the hope expressed in 1746 of
a smaller boiler and more elastic steam[119] was partially realized in
the engine and boiler of Trevithick, sen., in Bullan Garden in 1775,
followed in 1780 by the competing engine erected by Watt in Dolcoath
Mine, under Trevithick's management. Little further change was made
until 1799, when the globular boiler and internal tube of Trevithick,
jun., gave a second start to the use in large engines of more expansive
steam; and even this partial move was the result of years of thought
and practical experiment; for in 1792, when twenty-one years of age, he
was the elected judge on a competitive trial between the Watt engine at
Seal-hole, patented in 1782, and Hornblower's double-cylinder engine at
Tin Croft. Each engine performed a duty of ten millions, both of them
were called expansive, while in fact neither of them were so, for the
pressure of the steam in the boiler did not admit of it. As Lean says,
"As the steam used was raised but little above the pressure of the
atmosphere, it was found that the power gained did not compensate for
the inconvenience of a more complicated and more expensive machine."
Or, as Watt said to Robert Hart, "We resolved to give up the expansion
of the steam until we could get men that could work it," as he found
it more costly than profitable. Again in 1798, Trevithick's own
writing records his experiment in Dolcoath between the Bullan Garden
45-inch atmospheric engine and the Watt 63-inch great double-acting
engine, when the latter did sixteen millions to ten millions by the
atmospheric. At that very time he was constructing his high-pressure
steam portable engines, and in the following year, after seven years of
most active experience, prompted by the Watt lawsuit against Cornish
engineers, he in 1799 gave the beaten 45-inch engine steam of a higher
pressure from the stronger globular boiler. People, following the
ideas of Watt, were still afraid of Trevithick's plans, distinctly
laid down in his letters of 1806, recommending a cylindrical boiler
for the Dolcoath pumping engine, because similar boilers giving steam
to his whim-engines have enabled them to beat the Watt whims. This
continued until 1810, when the greatly-increased power and economy
of the high-pressure expansive steam pumping engine at Wheal Prosper
caused the neighbouring Dolcoath in 1811 to give Trevithick's plans
free scope. The long smouldering rivalry between low and high pressure,
on the eve of the final discomfiture of the former, burst forth in
loud words and evil prognostications, causing the mining interest of
Cornwall to appoint an examiner who should publish monthly the duty
performed by the various pumping engines, the first of which appeared
in the autumn of 1811, when Trevithick was building his boilers in
Dolcoath, and preparing the engines, as far as was possible, to submit
to strong steam. By expansive valves and suitable gear, balance of
power between the engine and the pump-work necessitating balance-bobs,
strengthening the pit-work to bear the more powerful and sudden
movement, and fifty other things, which we know must have presented
themselves in such work, occupied the greater part of Trevithick's time
from 1811 to 1814. That first report enumerates twelve pumping-engines,
probably all of them Watt engines, averaging a duty of seventeen
millions.

[Footnote 118: See Lean's Historical Statement, p. 154; published 1839.]

[Footnote 119: See vol. i., p. 7.]

We have before traced the rapid and immense increase in the power and
in the duty of Cornish pumping engines from 1811, and it may be taken
as comparatively true in the larger sense applying to the improvement
of the steam-engine everywhere.

Dolcoath Mine, one hundred years ago, under the management of
Trevithick, sen., followed by his son as the strong-steam engineer, and
by his grandson as one of the committee of management in these modern
times, has served during that long period to illustrate the progress of
the steam-engine, and still in active operation, was thus spoken of in
'The Times' of Dec. 18th, 1871:--"This old and extraordinary mine is
now raising about 100 tons of tin every month, worth from 8000_l._ to
9000_l._"




CHAPTER XXI.

ENGINES FOR SOUTH AMERICA.


 [Rough draft.]

  "SIR,              "CAMBORNE, _May 20th, 1813_.

 "Yours of the 7th inst. I should have answered by return, as
 requested; but an unexpected circumstance prevented my being at
 Swansea as early as proposed, which, as it happens, best suits your
 purpose as well as my own. I shall not be able to be there within
 twenty days from this time, of which I will give you timely notice. I
 hope before that time Mrs. Rastrick will be safe out of the straw. I
 have been detained in consequence of a strange gentleman calling on
 me, who arrived at Falmouth about ten days since, from Lima, in South
 America, for the sole purpose of taking out steam-engines, pumps, and
 sundry other mining materials to the gold and silver mines of Mexico
 and Peru. He was recommended to me to furnish him with mining utensils
 and mining information. He was six months on his passage, which did
 not agree with his health, and has kept his bed ever since he came on
 shore; but is now much recovered, and hopes to be able to go down in
 the Cornish mines with me in a few days. I have already an order from
 him for six engines, which is but a very small part of what he wants.
 I am making drawings for you, and intend to be with you as soon as
 they are finished. Money is very plentiful with him, and if you will
 engage to finish a certain quantity of work by a given time, you may
 have the money before you begin the job. The West India engine will
 suit his purpose. I shall have a great deal of business to do with you
 when we meet. In the meantime please to forward the thrashing engines
 to Cornwall as quickly as possible. The engine for Plymouth will be
 put to break the ground as soon as I can find time to go up there.
 Please to say when and by what ship I shall have the small engines.

  "I remain, Sir,
  "Your very obedient servant,
  "R. T.

  "To MR. JOHN U. RASTRICK,
  "_Bridgenorth, Shropshire._

 "The copper mine mentioned in my last is improving very fast."

The strange gentleman referred to was Don Francisco Uville, a person of
great influence in Lima, who a year or two before had travelled from
Peru to England and back, in search of steam-engines to pump water from
the ancient gold and silver mines then flooded and idle. Boulton and
Watt, at Soho, on being consulted, discouraged the attempt, because of
the difficulty of conveying heavy machinery over mountain pathways, and
also because their low-pressure vacuum engine, using steam but slightly
above atmospheric pressure, would be much less effective in the
comparatively light atmosphere on the high summits of the Cordillera
Mountains than in England. Uville, who had heard of the wonderful
ability of English engineers to construct steam pumping engines, was
utterly downhearted at this decision of the great Soho engineers, and
while dejectedly wandering through the streets of London, unconsciously
gazed into the shop window of Mr. Roland in Fitzroy Square, near the
spot on which Trevithick had run his railway locomotive three years
before.[120] Rumour of passed events may have led him to visit the ground
on which had worked a new kind of steam-engine. His searching glance
discovered among numerous articles for sale, an unknown form that might
be the talisman he had travelled thousands of miles in search of. The
shopkeeper informed him that it was a model of Richard Trevithick's
high-pressure steam-engine, which worked without condensing water,
or vacuum. If what he heard was true, why should it not work equally
well in the light atmosphere of the mines? The great engineer at Soho
might be in error or ignorance. The experiment, as a last resource, was
worth making. He would pay the 20_l._ for the model, carry it to the
mines of Cerro de Pasco, in the high mountains above Lima, where, if it
worked as well as it did in London, the rich mines of Peru would again
reveal their long-hidden treasure. The model was conveyed by ship to
Lima, and then on a mule up the narrow precipitous ascents to Cerro de
Pasco, over mountains more than 20,000 feet high. Fire was placed in
the small boiler as he had seen it done in London, and with the same
result, to the great joy of Uville, who determined to revisit England
in search of the inventor of this new and wonderful power. On his
return voyage, when rounding Cape Horn, bets were made on the chances
of his finding the man who had invented the high-pressure steam-puffer
engine,[121] and of his being able to persuade such a person to make the
required engines and accompany them to Peru. Such gloomy forebodings
ended in an attack of brain fever. The vessel touched at Jamaica,
where Uville was landed. On recovering health and strength he embarked
for England in one of the packet-ships, and during the voyage still
spoke of the object of his search. A fellow-traveller, called Captain
Teague, rejoiced him by saying, "I know all about it; it is the easiest
thing in the world. The inventor of your high-pressure steam-engine
is a cousin of mine, living within a few miles of Falmouth, the port
we are bound for." On landing, Uville, still weak and obliged to keep
his bed, was told that Trevithick, the engineer, lived in London, and
was constructing the Thames Tunnel; but further inquiry showed that he
also had suffered from brain fever, and had just returned to Penponds,
only a few miles from Falmouth. On the 10th of May, 1813, a letter
reached Trevithick, requesting him to visit the sick Uville, and in a
fortnight from that time the engineer had mastered the requirements
of the Peruvian mines, and had designed and made arrangements for the
supply of six pumping engines, together with the pumps and all things
necessary for the underground workings; the whole to be delivered in
four months.

[Footnote 120: See vol. i., p. 194.]

[Footnote 121: See London locomotive, vol. i., p. 198.]

 [Rough draft.]

  "SIR,               "CAMBORNE, _May 22nd, 1813_.

 "I have engaged to get six engines, with pit-work, &c., to send
 abroad. A great part of the wrought-iron work and the boilers I have
 arranged for in Cornwall. These engines will be high-pressure engines,
 because the place they are for has a very deep adit driven into the
 mountain; and lifting condensing water to the surface would be a
 greater load than the whole of the work under the adit level.

 "I call a set of work, a 24-inch cylinder single engine, 6-feet
 stroke, piston, cylinder bottom, single nozzle, with two 5-inch valves
 and perpendicular pipe; no cylinder top; the piston-rod not to be
 turned; 3-inch safety-valve, fire-door, two small Y[**symbol] shafts
 and gear-handles, &c.; a good strong winch set in a broadish frame,
 such as is often used on quays or in quarries, 25 fathoms of 12-inch
 pumps, a 12-inch plunger, an 11-inch working barrel, clack-seat and
 wind-bore, with brass boshes and clacks, a force-pump for the boiler,
 and 10 fathoms of 3-inch pipes to carry the water to and from the
 engines. I have engaged to supply six full sets of the above-mentioned
 materials.

 "All these castings must be delivered in Cornwall in four months from
 the time the orders are given; therefore, if you take the job, or any
 part of it, you must enter into an engagement to fulfil it in the
 time. As there ought not to be a moment lost, I wish you to answer me
 immediately in what time you will deliver those materials in Cornwall;
 or otherways, what part of them you can execute in the time.

 "I am making the drawing, which will be ready before I can receive
 your answer. For whatever part of the job you may engage I will lodge
 the money to pay for the whole in Mr. Fox's hands, which will then
 be paid for before you begin the work, as soon as you execute the
 agreement.

  "R. T.

  "MR. PENGILLY, _Neath Abbey, South Wales_."

It is an odd coincidence that while writing of the events of
fifty-eight years ago, pumping engines are being sent to those same
mines with the steam-cylinder in twenty-two pieces, no piece to weigh
more than 300 lbs.--a facility in mechanical arrangements not enjoyed
by Trevithick--having Trevithick's high-pressure boilers, giving steam
of 50 lbs. on the inch.[122]

[Footnote 122: Made by Harvey and Co., Hayle, 1870.]

 [Rough draft.]

  "SIR.                "CAMBORNE, _June 2nd, 1813_.

 "I drop you this note just to inform you that I have begun your job.
 Yesterday I engaged a great many smiths and boiler-builders, who set
 to work this morning. I have also engaged all the boiler-plates in
 the county, which will be sent to-day to the different workmen. The
 master-smiths that I have engaged are the best in the kingdom. I have
 obligated them to put the best quality of iron, and to be delivered
 at Falmouth within four months. I have been obliged to give them a
 greater price than I expected, otherwise they would not turn aside
 their usual business employment for a short job of four months.

 "Mr. Teague is with me, and one other, assisting about the drawings.
 If you call at Camborne about Friday, shall be able to show you
 the designs. The drawings for the castings will be sent to the
 iron-founders by the end of this week; and by the end of next week
 shall have the whole of the different tradesmen in full employ. If
 you wish to have a greater quantity of machinery ready by the end of
 September, there ought to be as little time as possible lost in giving
 your orders. I can get you double the quantity, provided you give the
 orders in time.

 "As soon as it is convenient to you to arrange the payments I would
 thank you to inform me, because we find in practice that the best way
 to make a labouring machine turn quickly on its centres, is to keep
 them well oiled.

  "R. T.

  "F. UVILLE, Esq., MR. HOOPER'S, _Falmouth_.

 "N.B.--If you intend to be at Camborne, please to drop me a note by
 post, and I will be at home."

In all Trevithick's moves there was a scramble for money, in which
he invariably came worst off. He could give a good hint that working
centres would not turn well without the essential oil; but he failed
to apply the principle to himself. Liberal words and golden prospects
carried him off at once; and before Uville was strong enough to visit
the Cornish mines and to fully explain what he wanted, the machinery
was being made, though at that same time the thrashing and ploughing
engines, and the locomotive and rock-boring engine, and the great fight
with Watt at Dolcoath, were in progress.

 [Rough draft.]

  "MR. RASTRICK,         "CAMBORNE, _June 8th, 1813_.

 "Sir,--Enclosed I send to you a drawing for a set of pumps for one
 of the engines for South America, with a drawing for a part of the
 castings for one of the boilers, for you to make a beginning. The
 drawings for the engines I will send in a few days. The Spanish
 gentleman who is now gone to London to arrange his money concerns,
 will be down again in about ten or twelve days, and then we shall both
 call at Bridgenorth, and bring with us the engagement for you to sign,
 for the performance of such quantities of work as you can execute in
 four months.

 "I have made arrangements with the smiths and boiler-*builders here,
 to weigh and pay at the end of every week. The regulation of your
 payment is left to you to point out in any way you please. As time is
 of the greatest consequence, I hope you will set to work immediately.

 "The reason for making the pumps so short, is on account of the
 extreme badness of the roads over the mountains, where these engines
 are to be conveyed, it being almost impossible to carry above five
 hundredweight in one piece. The West India engine is sold to send to
 Lima, but not to be conveyed over the mountains. I shall also bring
 drawings with me for one or two winding engines for the same place.
 Please write to me by return of post.

  "R. T."

 [Rough draft.]

  "CAMBORNE, near TRURO, _June 11th, 1813_.

  "MR. FRANCIS UVILLE,

  "at MESSRS. CAMPBELL AND CO.'S, London.

 "Sir,--I have your favour of the 9th instant, respecting the weight
 of the largest parts of the engines. I will take care to reduce the
 weight if possible, so as to be carried on the backs of mules.

 "By the time I receive your letter I shall have arranged the whole
 of the engine business, and intend to go immediately to Wales and
 Shropshire, to get the engagements executed for the performance of the
 work by the time proposed. I shall write to you again before I leave
 home, and as soon as I arrive in Wales will also write to you. I shall
 not stay in Wales above two days, but go to Bridgenorth in Shropshire,
 where I hope to have the pleasure of meeting you, as it will only be
 about twelve hours' ride out of your road to Cornwall.

 "In the North I shall introduce you to the sight of a great deal of
 mining and machinery, and in about ten days from the time you arrive
 at Bridgenorth, shall be able to accomplish the business so as to
 return again to Cornwall.

 "I would thank you to inform me as early as you can, of the number
 of engines you intend to get executed by the proposed time, because
 when I am in the North I shall be able to arrange with the founders
 accordingly. The smiths are all at work for you.

  "R. T."

 [Rough draft.]

  "MR. UVILLE,          "CORNWALL, CAMBORNE, _June 19th, 1813_.

 "Sir,--Your favour of the 9th instant, dated from Falmouth, I
 received, and in return wrote to you immediately--directed for you at
 Messrs. Campbell and Co.'s, London. As you said in your last letter,
 that immediately on your arrival in town you would write to me, I have
 expected every post since last Tuesday would have brought me a letter;
 but as I have not received it according to your promise, I am fearful
 that your letter may be unexpectedly detained, especially as you told
 me the last time I saw you at Falmouth, that you would enclose me
 a bank post bill. All the founders and other tradesmen are in full
 employ on your engines.

 "I intended to have left Cornwall for Wales and Shropshire by
 this time, with the founders' articles for execution; but being
 disappointed in not hearing from you, agreeable to our appointment, I
 shall delay it until I hear from you, which I must request you to have
 the goodness to do by return of post, because those delays make very
 much against the execution of your work; and as time is of so great
 a consequence to you, I hope you will not lose a moment in writing
 and giving me the necessary instructions, with a few drops of that
 essential oil that you proposed sending me on your arrival in town.

  "R. T."

The sugar rolling-mill engine that had been made for the West Indies
so pleased Uville that he purchased it at once, intending it for the
Mint at Lima. He also ordered one or two winding engines, in addition
to the pumping engines. Trevithick had arranged that no piece should
exceed 560 lbs. in weight. Then came Uville's order, "if possible to
be reduced so as to be carried on the backs of mules." Since that time
the path on the mountains has been improved, yet the present limit
of weight is 300 lbs. The absence of the promised bank post bill was
another difficulty.

 [Rough draft.]

  "CAMBORNE, _June 23rd, 1813_.

  "MR. FRANCIS UVILLE,

  "at MESSRS. CAMPBELL AND CO.'S, Park Buildings, London.

 "Sir,--Your favour of the 19th instant came safe to hand.

 "I was in hopes that I should have found a remittance enclosed. All
 the tradesmen that I have employed on your work were to have been paid
 every Saturday, and I made my arrangement with you accordingly. Unless
 this mode of proceeding is followed up, you cannot get your work done
 in any reasonable time, especially as you are an entire stranger. For
 my own part I have placed the greatest confidence in your honour, with
 which I am fully satisfied.

 "But I have to get this work from a great number of different
 tradesmen, and must make regular payments agreeable with my
 engagements with them. As the articles are about to be executed by
 different tradesmen, regular weekly payments ought to be established,
 of which I informed you before the work began.

 "I am ready for my journey to Wales and Shropshire, but cannot proceed
 with further engagements until I hear again from you. I have placed
 the fullest confidence in your word, a proof of which you have in the
 great exertion I have made to get the work done; but unless you in
 return place some confidence in me, or any other engineer that you may
 employ, a work of this magnitude cannot be carried on with promptitude.

 "As the whole of the work in my part has been put into immediate
 operation, it would be a very serious loss both of money and time to
 discharge the hands. I hope you will fully consider this business, and
 must beg you will have the goodness to write to me by return of post.
 On receiving the needful from you I shall leave Cornwall for Wales and
 Shropshire.

  "R. T."

Trevithick for once in his life was wise, and would not start on his
journey to Bridgenorth until the money had reached him. This prudent
resolve was soon forgotten in the love of making the steam-engine
useful; and as such creations in his hands grew into shape and size
before other men would have got through preliminary discussions,
pecuniary difficulties sprang up, as mushrooms do in a night.

 [Rough draft.]

  "CAMBORNE, _September 4th, 1813_.

  "MESSRS. HAZELDINE, RASTRICK, AND CO.,

 "Gentlemen,--Enclosed you have three of Mr. Uville's drafts, value one
 hundred and fifty pounds.

 "I should have sent it in one draft, but had not a suitable stamp. The
 castings, pipes, ale, &c., arrived safely. I hope that all the boilers
 and wrought-iron work will be finished by the end of this month, and
 shipped off for London. Immediately after Mr. Uville and I shall leave
 Cornwall for Bridgenorth on our journey to town. We are both very
 anxious to see the 'Sanspareil' engine at work, and hope you will have
 it ready by that time. I have received orders from different persons
 since I have been here, for steam-engines for the West Indies, and
 must, if possible, have three ready early in November, as the ships
 sail then that will take them.

 "I wish you would say in your next if this can be done in time,
 because these persons are very extensive agents for the planters, and
 are extremely anxious to generally adopt them in the West Indies.

 "We find from your letter that you are getting on pretty fairly with
 Uville's work.

  "I remain,
  "Your very humble servant,
  "RICHARD TREVITHICK."

 [Rough draft.]

  "GENTLEMEN,       "CAMBORNE, _September 7th, 1813_.

 "After writing to you on Sunday last, Mr. Uville received letters from
 Cadiz, from the Spanish Government, informing him that there was a
 line-of-battle ship there that should take the engines to Lima. Now as
 this ship is detained for this purpose, all possible dispatch must be
 made to get the whole of the materials shipped as early as possible
 for Cadiz. I am pushing the smiths as hard as possible, and you must
 do the same at your works, that the greatest dispatch may be made.
 I am ordered by Mr. Uville to request you to get one water-engine,
 pumps, &c., complete, one winding engine, winding apparatus, &c.,
 complete, and one crushing apparatus, complete, in addition to the
 former order. I wish you would also get on as fast as possible with
 the new engine, but do not let this engine prevent the getting forward
 the work for Lima.

 "I wish to have made apparatus to work expansively, and also a
 temporary water-pump, to load the engine, so as to prove its duty by
 the consumption of coal.

 "If the jobs are not completed by our arrival, you need not expect any
 rest until its completion. Your answer will oblige,

  "R. T."

 "MESSRS. HAZELDINE, RASTRICK, AND CO."

The money difficulty was for a time surmounted, with a prospect of
the completion and shipment of the work for London within four months
of the giving of the order; and the Spanish Government proposed that
a line-of-battle ship should take the engines to Lima from Cadiz. An
order was given for another pumping engine and another winding engine,
to be provided with gear for working expansively, and a temporary
water-pump, that in case of need the amount of work the engines could
do with a given amount of coal might be tested. A crushing machine, now
called "quartz-crusher," also formed part of this additional order.

The new engine, which he hoped they would get on with, was probably the
steam locomotive plough then being constructed at Bridgenorth.

 [Rough draft.]

  "GENTLEMEN,      "CAMBORNE, _September 22nd, 1813_.

 "I have your favour of the 14th instant, and hope to find you as
 forward on your job on our arrival at Bridgenorth as you state. I
 expect all the boiler and smith work will be shipped for London early
 in October; we shall then leave Cornwall for your works, at which time
 you will be very much annoyed with our company, unless we find your
 assertions grounded on facts. Enclosed I send you Mr. Uville's draft
 for 150_l._ Your receipt for the draft enclosed in my letter of the
 16th instant has not yet arrived.

 "I hope you will also have all the apparatus ready to try the new
 engine; Mr. Uville is very anxious to take the first of these new
 engines with him. When you send a receipt for the enclosed, please to
 say what state of forwardness the whole of our work is in, and do not
 neglect a moment to get the whole executed with all possible dispatch.

 "Nothing short of a want of cast iron will confine our friend in
 England one day after the end of this month.

  "I am, Gentlemen,
  "Your very humble servant,
  "RICHARD TREVITHICK.

 "MESSRS. HAZELDINE, RASTRICK, AND CO."

It seems probable that in 1813 a railway locomotive, with apparatus
for rock boring, and steam-crane, was made for South America as the
forerunner of the 'Sanspareil' of 1829.

 [Rough draft.]

  "GENTLEMEN,      "CAMBORNE, _October 1st, 1813_.

 "I received your favour of the 27th last evening, and now enclose you
 another draft of Mr. Uville's for 150_l._ We shall wait impatiently
 for your next letter to know when you will finish. Mind, this is
 the 1st of October, and agreeable to promise the time is up. Mr.
 Uville wishes you to cast sixty carriage-wheels for him, 11 inches
 in diameter from out to out, and to weigh about 20 lbs.; cast them
 of strong iron, and of a strong pattern, to take a 1-1/2-inch axle
 by 2-1/2 inches deep in the hole; also cast four plunger-pistons 11
 inches diameter to suit the 11-inch working barrels, provided it
 should be used for the purpose of a plunger. They must be in every
 respect the same as the 14-inch plunger-pistons, only 3 inches less in
 diameter.

 [Illustration]

 "Soon after the receipt of your next letter you may expect to see us,
 as a vessel has been engaged to take all the boilers and smith work on
 board to-morrow week for London.

  "I remain, Sir,
  "Your humble servant,
  "RICHARD TREVITHICK.

 "MESSRS. HAZELDINE, RASTRICK, AND CO."

Probably those cast-iron wheels were ordered with a view to steam
locomotion in the Cordilleras. An engine is described in the invoice as
having chimney, axles, carriage-wheels, &c.

 [Rough draft].

  "GENTLEMEN,     "CAMBORNE, _October 11th, 1813_.

 "On making the drawings of the engine with the winding and crushing
 apparatus, when at work I find that if there is no crank, but the
 sweep rod is connected to a pin in the arm of the fly-wheel; in that
 case the fly-wheel will cut off the engineer from getting at the
 cock; but if the sweep is connected to a crank, then there will be
 sufficient room. The copy of materials taken from your books and given
 to Mr. Uville does not say in which way it was intended. I send you a
 sketch how it will stand worked by a pin in the fly-wheel, and also
 if worked by a crank over the cylinder, with the fly-wheel outside
 the wood partition of the house. If you have cast all the parts for
 the winding engine, you should try to alter it, having the fly-wheel
 outside the wall of the house, and a crank for the inside end of the
 shaft. The fly-wheel shaft will be nearly the same length both ways,
 only it must be long enough for the fly-wheel to pass between the
 wood partition and the 4-feet cog-wheel. The centre of the winding
 cylinder will be 17 inches from the outside of the wood end of the
 house, against which the fly-wheel ought to run. I have received
 your favour of the 5th instant, and have enclosed, agreeably to your
 request, a draft of Mr. Uville's for 800_l._, which will be the last
 from Cornwall. All I have to say is, you have taken longer time for
 the completion of your work than you first proposed, which has made
 Mr. Uville apprehensive that it will be the means of his losing the
 Spanish ship promised him to take the engines. He desires me to inform
 you that he has complied with this advance on purpose to enable you to
 push your work with the utmost exertion.

 [Illustration: WINDING ENGINE FOR SOUTH AMERICA.]

 "Please to inform us the precise time we must quit Cornwall for
 Bridgenorth; we now wait entirely on you without any other thing to
 engage us. I fear Mr. Rastrick being so much from home will impede
 our job. If we miss this ship it will certainly make much against us
 all, losing three or four months in getting a South Sea whaler, and
 having the engine in a vessel not able to defend herself against an
 enemy, and having to pay 15 or 20 per cent. insurance, and prevent our
 getting other orders for another set of engines, and if taken by the
 enemy perhaps altogether damn the undertaking. Therefore I would have
 you to well consider the great inconveniences attending delay.

 "I think I need not say much more to you on this head, as you ought to
 feel more for your own interest than I can scribble to you on paper.

  "Yours, &c.,
  "R. TREVITHICK.

 "MESSRS. HAZELDINE, RASTRICK, AND CO."

This rough hand-sketch and letter fully describing his requirements,
is an illustration of the facility with which Trevithick designed his
engines and made known his wishes to others.

 [Rough draft.]

  "GENTLEMEN,      "CAMBORNE, _October 23rd, 1813_.

 "Mr. Uville wishes everything to be sent off as soon as finished,
 except the rolling engine, which is to remain until he arrives. We
 intend to leave Cornwall for Bridgenorth on Monday, November 1st. You
 may expect to see us three days after that date. The wheels ordered
 for the carriages are to run on the ground and not on railroads. Mr.
 Uville now wishes to have seventy-two instead of sixty as ordered
 before.

  "I remain, Gentlemen,
  "Yours, &c.,
  "R. TREVITHICK.

 "MESSRS. HAZELDINE AND CO."

The last-named engine was intended for the coinage operations in the
Mint at Lima. The use of railway locomotion had been under discussion
with the engine builders, and probably those particular carriage-wheels
were ordered in the hope that the portable engine built for conveying
itself from place to place in the sugar plantations of Jamaica, would
in the Cordilleras be made to draw waggons on common roads.

The hand sketch of the winding engine in the letter of the 11th
October, was to correct an error in an order hastily given a month
before; when, to save time, outline instructions for this complicated
work were hurriedly sent to the manufacturer, that a commencement
might be made while the more perfect detail drawings were being
completed; the first-proposed position of the fly-wheel would prevent
the engineman from conveniently reaching the four-way cock; Trevithick
therefore suggested that the fly-wheel should be moved to the outside
of the house, and a crank placed on the end of the driving shaft
in lieu of the crank-pin in an arm of the fly-wheel. The sketch
illustrating this change makes us fully acquainted with the kind of
winding high-pressure steam-puffer engines of 8-horse power, with
open-top cylinders of 12 inches in diameter and about 3 feet 6 inch
stroke, sent to Peru in 1814. Steam, of 30 lbs. to the inch above the
pressure of the atmosphere, was admitted under the bottom of the piston
by a cock moved by an eccentric on the fly-wheel shaft; the gradual
closing of the cock reduced the supply of steam when about one-third
of the stroke had been made, wholly cutting it off some time before
its completion, making it a high-pressure steam expansive engine. The
movement of the cock then turned the steam from under the piston into
the chimney blast-pipe, and the down-stroke was performed by the weight
of the descending piston, made more than usually deep and heavy to
prevent the tendency to twist in the cylinder from the angle of the
jointed connecting rod, and also by the momentum of the fly-wheel and
its balance-weight, moving at a speed of thirty strokes a minute. Its
boiler was the Trevithick wrought-iron cylindrical, with internal tube
and fire-place, but so arranged that if necessary the fire could be
placed in brick flues under the boiler, returning through the tube.

The cylinder for the winding engine was probably fixed in the boiler,
costing, with whim-barrel and winding apparatus complete and ready for
work, 210_l._ Does the reader ask, Did so cheap an engine ever work?
Or perhaps his knowledge of engineering gives rise to the question,
How did it work? for it looks like a Newcomen of just exactly a
hundred years before, only it needs no injection water or great main
beam; and certainly it is not a Watt, for it has neither air-pump
nor condenser, nor vacuum, nor cylinder-cover, nor parallel motion,
nor any other thing like Watt invented; but it has high-pressure
steam, which he disapproved of, and it really worked thousands of
miles away, where there were no mechanics to keep it in order, and on
mountains so difficult of access, and in so light an atmosphere, that
Watt, who had the first chance of supplying steam-engines to the New
World, declared it to be impossible. The pumping engines are described
in Trevithick's note of 22nd May. They also were high-pressure
puffer-engines with open-top cylinder, 24 inches in diameter, 6-feet
stroke, with a cross-head working in guides, and side rods connecting
to the pump-rods. Two valves turned the steam on and off from under the
piston, with the ordinary gear and handles. The boiler was similar to
that for the winding engine, but larger, and had not the cylinder fixed
in it; a balance-beam regulated the movements, as it had no great main
beam, and differed from ordinary engines just as the winding engine
did. The power was 33 horses, and with an 11-inch pump barrel, 150 feet
of 11-inch pumps, a winch, and all apparatus necessary for draining the
mine, the cost was but 1400_l._


[Rough draft.]

  "PLOUGH INN, BLACKWALL, _December 28th, 1813_.

  "MR. RASTRICK,

 "Sir,--I am requested by Mr. Uville to write to you, to push the
 boilers as fast as possible. A ship will sail for the South Sea
 fishery in about five weeks, and will engage to take the whole of
 the engines. We have not finally closed with her, because we cannot
 state the exact time until we hear from you. You must not lose a
 moment in sending the boiler to town. I should have gone to Cornwall
 before this, but have been detained, getting a ship; and I do not like
 leaving until my agreements are executed, which cannot be done until
 the beginning of next week.

 "I have been obliged to have all the transactions between the mines,
 and the Spanish Government, and Mr. Uville, translated into English,
 before the outlines of an agreement could be drawn up, which has been
 a most tedious job.

 "Most of the people have been out of town, and those that were not
 would do no business in the Christmas, which has occasioned a loss of
 near ten days.

 "As soon as the agreements are executed, I will immediately send to
 you money from this place. I have been kept so long here, that it will
 not be worth returning to Cornwall until after Mr. Uville sails. I
 shall be at Bridgenorth in about ten days, and will remain until the
 work is finished. Write how the work is getting on, and what state the
 winding engine is in.

  "Yours, &c.,

  "RD. TREVITHICK."


[Rough draft.]

  "DEAR SIR,

  "CAMBORNE, _March 4th, 1814_.

 "Your favour of the 23rd February was sent to me from Bridgenorth. I
 have also received your favour of the 1st instant, and will attend to
 the drawings you mention, and be prepared to meet you as early as you
 please, only give me as much notice as you can.

 "I hope by this time that Mr. Page has done something toward the
 needful, to be at your service. I have, agreeably with your letter
 this day, desired Capt. Thomas Trevarthen to hold himself in readiness
 for London about the end of this month. I have not yet seen Bull. I
 wish you to write me if I am to give him notice also to hold himself
 in readiness for town. I fear that those two persons will not be
 sufficient to conduct the work with speed, especially if Capt.
 Trevarthen should be unwell; he is a good miner and pitman, and could
 assist in fixing the engines. Bull can only act as an assistant to an
 engineer, therefore neither of them can take the sole direction of the
 work.

 "There will be those four large boilers to be put together on the
 spot, which neither of those persons know but little about. I think
 it would take a great charge and care from your mind to have a third
 person with you that could go through the whole of the undertaking,
 especially as the distance from England is so great. This undertaking
 of such immense magnitude and value ought not to depend solely on your
 own health, as neither of the other two could get on without your
 assistance in laying down and planning the outline of the whole of
 the work belonging to the machinery. If any one of the parts should
 be lost or broken, it would require some ability in that country to
 contrive a substitute. The expense of a third able man might prevent
 much loss of time and difficulty, and would not be an object in a
 business of such a scale as you have commenced with.

 "I recommend a third person, that you might count on a speedy and
 effectual start. Even in this kingdom, where machinery is so well
 understood, I have known several good undertakings fail, from not
 employing at first an experienced engineer to conduct the work; which
 I am doubtful would be the case at Pascoe, if you were not able to
 attend yourself to the erection, and do not take a person with you for
 that purpose. I beg your pardon for thus attempting to recommend to
 you a third person to go out; but I think a work of this magnitude,
 where expedition is important, ought not to rest on the health of one
 man, especially under a changeable climate. Please to consult your
 friends, and give me your opinion on it in your next.

 "My health is much improved; my wife desires her best respects, and
 thanks for your present. Please to write soon.

  "Yours, &c.,

  "RD. TREVITHICK.

 "MR. UVILLE, _12, East Stien, London_."


[Rough draft.]

  "MR. PAGE,

  "CAMBORNE, _March 8th, 1814_.

 "Sir,--Yesterday Mr. Joseph Edwards, of Truro, informed me that Teague
 had given notice of trial, and that the case would come on at the
 Assize on the 26th, and requested me to desire you to write to him
 immediately, and give him the whole of the transaction relative to Mr.
 Uville's arrest in London.

 "He also wishes that some attention had been paid to the threat that
 Mr. Uville received from Teague's so-called friend, so as to ascertain
 whether it came direct from him, which he thought would have some
 weight in court. I shall attend to give evidence at the Assize with
 Mr. Edwards. I shall anxiously await a reply to my last. How does
 Harvey's business get on?

 "My respects to Mr. Day, and shall be very glad to find him recovering
 his health as fast as I am. A crust of bread and clear air are far
 preferable to luxuries enveloped in clouds of smoke and heaps of filth.

  "Your obedient servant,

  "RD. TREVITHICK.

 "P.S.--I hear that Teague is still in London, and that his furniture
 is removed to his friend's house, to save it from the hands of
 surrounding evil spirits."

Trevithick showed no undue amount of discontent on discovering that
Uville had led him into pecuniary difficulties, and even his tendency
to interfere in engineering matters was not hastily resented.

In December, 1813, while in London, arranging for a vessel to convey
the engines to Lima, and also to secure written agreements with
Uville, who expected to leave England in a week or two, the going into
the documents made known many weak points, one of them being shortness
of money. The expected week or two had lengthened out to three months,
and Uville was still in London, and Capt. Thomas Trevarthen and Bull
were to be there, ready to start, about the middle of March, 1814. Four
large boilers, in pieces, were to go for the pumping engines, to be put
together in the mines; and Trevithick strongly recommended the sending
a third man, to take general charge of the practical work, which Mr.
Uville thought he himself could manage.

Page and Day were lawyers, who drew up very long documents. Money to
pay expenses was raised by the sale of shares in a company formed by
Uville without sufficient authority, and Page was to go to the mines
to look after his own and the English shareholders' interests; between
them Uville was arrested, apparently for some trifle.


[Rough draft.]

  "MR. UVILLE,

  "CAMBORNE, _March 15th, 1814_.

 "Sir,--I shall write to him again by this post, and push him to send
 down the transfer of my shares, already agreed on, for my execution,
 and hope I shall be able to meet Messrs. Hazeldine and Co.'s demand
 before it will be due. The young man Bull has been with me. I told
 him I expected that you intended to take him with you, and Capt.
 Trevarthen is making preparation for going. I am glad you intend to
 take a third person with you. I have not thought or said anything to
 anyone about this business. Mr. Vivian informed me that, from the
 conversation he had with you on the subject, he had expected to hear
 from you. I can answer for Mr. Vivian's honesty, ability, and pleasant
 behaviour, and he is a person very suitable for the engagement, only
 that one failing of making too free with an evening glass, which
 you were not unacquainted with while in Cornwall at Dolcoath Mine. I
 do not like to take an active part in this business, because if any
 accident should happen to him, my sister or his family might charge me
 with being accessory to his going; therefore I must beg to be exempt
 from taking any part in this engagement.

  "I remain, Sir, yours,
  "RD. TREVITHICK."

 [Rough draft.]

  "MR. PAGE,    "CAMBORNE, _April 9th, 1814_.

 "Sir,--I have your favour of the 5th instant. I intend to be in town
 on Sunday week, but this need not prevent their writing to me here;
 and both you and they may still be doing your best towards disposing
 of shares.

  "Your obedient servant,
  "RD. TREVITHICK."

 [Rough draft.]

  "MR. UVILLE,    "CAMBORNE, _April 9th, 1814_.

 "Sir,--I intend to be in London on Sunday, the 17th, and shall call
 immediately on this person for money, which shall be at your service.
 Wheal Alfred and Wheal Prosper agents wish you a prosperous voyage,
 and success in your mines.

  "I remain, Sir,
  "Your obedient servant,
  "RD. TREVITHICK."

Trevithick was now embarked with a crew of speculators, and in payment
for his services was made a partner, and sold a portion of his shares
to pay for the engines which Uville had ordered.

Henry Vivian, his brother-in-law, and the brother of his late partner
Andrew Vivian, wished to be the third person engaged to go with the
machinery to America. Trevithick spoke of his honesty and ability, but
declined, on account of the family relationship, to take any part in
the appointment.

The two notes on the 9th April, 1814, close the correspondence. Page
was busy selling shares to raise money, and Trevithick was to get some
money, which was to be at the service of Uville.

The delay between this period and the time of starting was mainly
caused by financial and other arrangements managed by Uville. On the
1st September, 1814, Uville, Henry Vivian, Thomas Trevarthen, and
William Bull sailed from Portsmouth for Lima in the 'Wildman,' taking
with them four pumping engines, with pump-work and rods complete; four
winding whim-engines, with all winding apparatus complete; one portable
locomotive engine on wheels, to be used for a rolling mill or other
purposes; one mill for grinding ore; and one rolling mill, probably
for the Mint at Lima. These nine steam-engines, with their apparatus
complete for work at the mines, cost 6838_l._; the grinding and rolling
mill cost 700_l._ more; but various other expenses more than doubled
the amount, which reached the large sum of over 16,000_l._

On reference to the conditions of agreement under which Uville acted,
dated 17th July, 1812, Don Pedro Abadia, Don José Arismendi, and Don
Francisco Uville, were partners engaging to drain a range of mines.
Uville was to go to London to purchase two steam-engines, and was
authorized to expend $30,000 (say 6000_l._). $2000 (say 400_l._) was to
be paid to him as the value of Trevithick's model, which he had a few
years before bought in London for 21_l._ He was to engage one or two
English workmen. No new partner was to be allowed. They also contracted
with the various workers of mines in Yauricocha, Yanacancha, Caya
Chica, Santa Rosa, and in the mining ridge of Colquijilca, for a period
of nine years, to commence within eighteen months of that time, to
sink a general pit for the drainage of those mines, and to pump out
the water by steam-engines. The payment for this drainage was to be
one-twentieth part of the ore raised by the different mines.

 "An agreement made at London this 8th day of January, 1814, between
 Don Francisco Uville, of Lima, in the Viceroyalty of Peru, of the one
 part, and Richard Trevithick, of Camborne, in Cornwall, engineer,
 of the other part. Whereas, by an agreement of partnership made and
 signed at Lima, and whereas the said Francisco Uville did in pursuance
 of his contract with the said miners soon after the ratification
 thereof, embark for England, for the purpose of fulfilling the same on
 his part, and on his arrival there in the month of April last, made
 application to the said Richard Trevithick, who is an experienced
 engineer and miner, and requested him to assist him in promoting
 the object of his journey, which the said Richard Trevithick (being
 penetrated with a high sense of its utility) agreed to do, and hath
 accordingly applied himself wholly to that object, ever since the
 arrival of the said Francisco Uville in England: And whereas under
 the direction of the said Richard Trevithick, and by the orders of
 the said Francisco Uville, various machines and engines have been
 made for the purposes of the said concern, a part of which has been
 already paid for by the said Francisco Uville; but several of the
 bills brought by him to England not having been honoured, by reason
 of the absence from England of the parties upon whom they were drawn,
 the said Francisco Uville hath not at present sufficient funds to
 answer the engagements he has entered into in this country, and Don
 Juan ..,[**] to whom he was in that case directed by his partners to
 offer shares in the said concern, and from whom he could have received
 supplies, not being at this time in London, the said Francisco Uville
 has agreed to admit the said Richard Trevithick to be a partner in
 the concern, upon his advancing and paying a proportionable part of
 the expenses necessary for carrying on the same. Now these presents
 witness that in consideration of the said Richard Trevithick having
 paid and agreeing by these presents to pay certain bills for machinery
 ordered by the said Francisco Uville to the amount of 3000_l._
 or thereabouts, the particulars of which have been ascertained
 and settled by and between the said Francisco Uville and Richard
 Trevithick, and also in consideration of the services which the said
 Richard Trevithick hath already rendered to the said undertaking, and
 of the future benefits which he is expected to perform for it, the
 said Francisco Uville for himself, and on the behalf and in the name
 of the said Pedro Abadia and José Arismendi (who will ratify these
 presents in the capital of Lima as soon as it shall be produced to
 them, to which the said Uville holds himself bound), Doth, by virtue
 of the power and authority given to him by his said partners, agree to
 admit the said Richard Trevithick to be a member of the said company,
 and doth hereby declare him to be a member thereof and a partner
 therein to the extent of 12,000 dollars, and as such, entitled to a
 share and interest in all the profits and advantages of the company
 in the proportion which the said sum of 12,000 dollars shall bear to
 the amount of capital employed by the company in the purposes of their
 establishment, which proportion will amount as nearly as can now be
 ascertained to one-fifth of the capital stock embarked in the said
 concern.

  "FRAN. UVILLE.
  "RICHARD TREVITHICK.

 "_8th January, 1814._"

So Trevithick paid 3000_l._ and received nothing for his engineer's
work, to be made a partner, contrary to Uville's limit of authority, in
a speculation that proved to be not worth a farthing.

The following is a summary of the detail invoice of engines and
machinery which left London for Lima in September, 1814, in charge of
Uville, just fifteen months after his landing at Falmouth in search of
Trevithick:--

 "Invoice of four steam-engines, four winding engines, one portable
 rolling engine and materials for ditto, two crushing mills, four
 extra-patent boilers, spare materials for engines, boring rods,
 miners', blacksmiths', and carpenters' tools, &c., shipped on board
 the 'Wildman,' John Leith, master, from London to Lima, by, on account
 and risque of Don Francisco Uville, Don Pedro Abadia, and Don José
 Arismendi, merchants at Lima. Dated 1814.

  To four steam-engines of 33-horse-power each           £  _s._ _d._
     (complete for lifting water with under-adit
      and house lift-pumps, and wrought-iron
       pit-work, rods, &c., at 1399_l._ 13_s._ each    5,598  12   0

  To four winding engines of 8-horse-power each,
      with whims, barrels, shafts, &c., complete
      for lifting ore, at 210_l._ each                   840   0   0

  To one portable steam-engine of 8-horse power,
      for rolling, with its chimney, axles,
      carriage-wheels, &c.                               400   0   0
                                                         -----------
                                                       6,838  12   0

  A mill for grinding ore               £517   0   0
  A rolling mill                         204   0   0
  Duplicates, sundries, freight,
  insurance, &c., &c.                  8,592   9   1
                                       -------------   9,313   9   1
                                                       -------------
                                                     £16,152   1   1"

The nine steam-engines, including a locomotive, with its chimney,
axles, carriage-wheels, &c., a crushing mill and a rolling mill,
cost but 7560_l._ Other expenses, for freight, insurance, &c., &c.,
increased the amount to 16,152_l._

William Williams,[123] on his return from the Cerro de Pasco Mines,
states:--

[Footnote 123: Residing at Angarrack, near Hayle, 1872.]

 "On the 3rd March, 1872, I saw in Yauricocha Mine two of Mr.
 Trevithick's engines at work; one of them was a horizontal 12-inch
 open-top cylinder pumping engine, about a 4-feet stroke; there
 were two fly-wheels about 10 feet diameter and a cog-*wheel 7 feet
 diameter, giving motion to two wrought-iron beams working a 10-inch
 pump bucket. The other was a 12-inch cylinder winding engine with
 a large fly-wheel. Three Cornish boilers, about 5 feet 6 inches
 diameter, with 3 feet 9 inch tube, 30 feet long, made of 7/16ths of an
 inch plates, supplied steam of 40 lbs. on the inch."




CHAPTER XXII.

PERU.


 "Conditions under which Don Pedro Abadia, Don José Arismendi, and Don
 Francisco Uville, establish the project of draining the mines by means
 of steam-engines, to be brought from England.

 "1st. The company is composed of three contracting persons without
 admitting therein any other whatever.

 "2nd. There are intended as a fund for the undertaking 40,000 dollars,
 to be divided into four shares in the following manner:--Two shares
 to Don Pedro Abadia, one to Don José Arismendi, one to Don Francisco
 Uville. Four shares, dollars 40,000.

 "5th. These principles of good faith and friendship being established,
 the project is to be carried into effect with the greatest possible
 activity, for which purpose, by the first opportunity, the funds shall
 be forwarded by Don Pedro Abadia to the amount of 30,000 dollars, with
 the necessary instructions for the construction of the machinery to a
 person who may be appointed.

 "7th. As it has been estimated that 30,000 dollars will cover the cost
 of two engines in England, if the said Uville finds another on credit,
 he is authorized to purchase it on account of the company.

 "11th. Should the undertaking yield profits, Uville shall also be
 credited for 2000 dollars for the value of the model.

 "12th. In the instructions that may be given to Uville, it shall be
 stipulated on what terms he may engage one or two English workmen.

 "LIMA, _17th July, 1812_."


 "_Contract._

 "1st. The present contract shall be considered binding for nine years,
 to be computed from the time the steam-engines may be erected in the
 different parts of these mines that may be judged suitable.

 "2nd. The miners herein contracting cede their mines in Yauricocha,
 Yanacancha, Caya Chica, Santa Rosa, and in the mining ridge of
 Colquijilca, and the company offer the means, steam-engines, and
 instruments for draining the same, and on these principles the
 obligations of both parties are as follow, to wit.

 "3rd. The company binds itself within the period of eighteen months,
 or sooner if possible, to bring over the steam-engines to drain
 successively the different parts of these mines, and immediately
 on their arrival to place them in Yauricocha, and afterwards in
 Yanacancha, Caya Chica, Santa Rosa, and in the mining ridge of
 Colquijilca, to sink a general pit for the collection of the waters at
 a depth of 40 varas from the adit or drainage level of Santa Rosa.

 "8th. Each miner whose mine situated in the parts above specified is
 not perfectly drained in consequence of the filtration or natural
 gravity of the water to the general pit, is to continue a tube to
 communicate with the said general pit on his own account, in order
 fully to enjoy the benefit of the draining, it being well understood
 that the company shall not refuse to admit the waters of any of the
 mines situated in this part whatever their quantity may be. And
 the company shall be further bound to supply funds to any miner
 who may not have sufficient to defray the expenses of such tube of
 communication at an interest of 6 per cent., to be refunded out of the
 first metals which may be obtained.

 "10th. The recompense to be made to the company for the general drain
 procured in the place or places agreed on, shall be, with regard
 to Yanacancha and Yauricocha, in consequence of the known richness
 of those places, and of the timber required by the softness of the
 ground to secure the mines, 15 per cent. on the ore that shall be
 extracted therefrom, and lodged either in the common depots or in the
 respective warehouses; and in the mines of Santa Rosa, Caya Chica,
 and Colquijilca, 20 per cent., which distribution is respectively to
 be made on the quantities obtained.

 "14th. That the miner who refuses to enter into this fair contract
 whose mines are benefited by the means of the engines, shall be
 compelled to pay the contributions and to perform what has been
 therein stipulated according to ordinance.

 "This contract being agreed to, the contracting parties signed
 respectively to be bound and compelled; and I, the Royal Judge
 and Sub-delegate hereof for His Majesty, signing it with all the
 contracting parties and witnesses before me on the said day, month,
 and year.

 "Pedro Abadia, José Arismendi, Francisco Uville, José Maria de Ulloa,
 Ignacio Beistequi, The Marquis de la Real Confianza, José Herressæ,
 Publo Anellfuertes, Ramon Garcia de Purga, José Antonio de Arrieta,
 José Camilo de Mier, José Lago y Lemus.

 "For myself and Don Remiqia, p. procuration Manuel Queypo, Rafael
 Doper, Juan Gonzalez, Augustin Zambrano, Francisco Rasines, Francisco
 Fuyre, Manuel Ysasi, Alberto de Abellaneda, Ysidro Crespo, Juan
 Antonio Arrasas, Pedro Gusman, Manuel Yglesias, Patricio Bermudez,
 Bartolome de Estrada. For the miners, Don Castano Villanueva, Juan
 Isidoro, Manuel de Santalla, Juan Palencia, Antonio Perez, Manuel
 Cavellero, Domingo Pallacios, Matias Canallero, Ambrosio Ortega,
 Francisco de Otayequi, Pedro de Arrieta, Juan de Erquiaga, José
 Zeferino Abaytad, Antonio Villaseca, Estanislas Maria de Arriola, José
 Maria del Veto, Ambrosio Guidones, Santiago Oreguela. For Don Pedro
 Mirales, p. procuration, Thomas Hidalgo, Nicholas Berrotarran, Barnabe
 Perez de Ybarrela, Augustin Bayroa, Francisco Xavier de Uribe, Manuel
 Varela. For my brother, Juan Francisco de Aspiroz, Juan Miguel de
 Aspiroz.

 "In the city of Los Reyes on the 26th September, 1812."

These extracts from an agreement drawn up by the leading men in Peru
in 1812 are proofs of remarkable energy. Rumours of the power of
steam-engines used in mines in England had reached Lima, Don Francisco
Uville was sent on a mission of inquiry, and in 1811 consulted Boulton
and Watt at Soho, who gave an opinion that their engines were not
suitable to so elevated a position where the atmosphere was so much
lighter than in England, and the difficulties of transit so great. On
his return to Lima he carried with him a small model of Trevithick's
high-pressure steam-engine. The Spaniards on seeing it work had the
good sense and courage to put aside the Watt report and adopt the
principle of the small but active high-pressure steam-puffer engine.

An influential company was formed, which sent Uville again to England
to seek out the high-pressure engineer and purchase his engines. What
stronger evidence could be given of the great difference between the
rival engineers and their engines? The one with low-pressure steam and
vacuum, the other with high-pressure steam and without vacuum.

The three persons contracting to drain the Peruvian mines agreed
that no other should be allowed to join them in the contract; two
steam-engines were to be purchased, and if convenient a third engine
might be ordered on credit. One or two English mechanics were to
accompany the engines which the contractors engaged should be in Lima
within eighteen months. Ten months had passed before Uville reached
Trevithick, and when in May, 1813, he communicated to the Cornish
engineer the same wants that he had made known to Watt two years
before, how different was the answer received. "I engage to supply in
four months six 24-inch cylinder high-pressure steam pumping engines,
with pumps and all necessary apparatus complete."[124] This promise was
nearly fulfilled,[125] but want of money, the ordering of additional
machinery, and difficulty in finding a ship,--for Spain was then at
war, or on the verge of it, with the South American republics,--delayed
for a time the completion of the order; but within eight months even
the additional work seems to have been ready, and the following
agreement was entered into, though the ship with her freight of _nine_
steam-engines did not leave England until September, 1814, fifteen
months after Uville's first meeting with Trevithick.

[Footnote 124: See Trevithick's letter, 22nd May, 1813, vol. ii., p. 198.]

[Footnote 125: See Trevithick's letters, 22nd Sept. and 23rd Oct., 1813,
vol. ii., pp. 206, 209.]

 "_Agreement dated the 8th January, 1814._

 "The said persons from whom he (Uville) would have received supplies,
 not being at that time in London, the said Francisco Uville has
 agreed to admit the said Richard Trevithick to be a partner in the
 concern, upon his advancing and paying a proportionable part of the
 expenses necessary for carrying on the same. Now these presents
 witness, that in consideration of the said Richard Trevithick having
 paid, and agreeing by those instruments to pay certain bills for
 machinery ordered by the said Francisco Uville to the amount of
 3000_l._, and also in consideration of the services which the said
 Richard Trevithick hath already rendered, and of the future benefits
 which he is expected to perform, doth agree to admit the said Richard
 Trevithick a partner therein, as nearly as can be ascertained to
 one-fifth share of the whole.

 "He hath planned and directed the particular construction of three
 steam-engines, and hath for that purpose taken many journeys to
 manufacturing towns and other places.

 "He hath given to the said Francisco Uville a general knowledge of
 English mining, miners' tools, winding and crushing engines, &c., &c.,
 and for that purpose hath taken him to various mines in England, to
 which the said Richard Trevithick, through his interest, had access.
 He hath instructed the said Francisco Uville in the art of making
 drawings of mines, and in engineering.

 "He hath furnished him with various drawings of English mines, and
 plans for the future working of Spanish mines, and hath given to him
 every other engineering and mining information.

 "He hath increased the power of the three engines above mentioned to
 the extent of one full third, without making any additional charge
 for so doing, and he hath agreed to supply the said company with a
 fourth engine, and to wait for the payment of it, until the return
 of the said Francisco Uville to Lima, in recompense for all which
 the said Francisco Uville doth for himself and his partners grant
 to the said Richard Trevithick one and quarter per cent. of the net
 produce or profits (all expenses first deducted) of the ore extracted
 from the said mines, and as a further recompense, doth appoint him
 sole engineer in Europe for all the machinery that shall be used or
 required."

The nine steam-engines, with apparatus for minting, crushing ores,
draining, winding, and even locomotion, with miners' tools complete
down to mine ladders, borers, picks and gads, and hammers, were
received by a large and influential body of Spaniards residing near
Lima, under the special patronage of the Viceroy. The machinery had
then to be taken up precipitous tracks that foot-passengers trembled to
walk on, to the height of more than 15,000 feet.

The calculated profit was 500,000_l._ a year, of which 100,000_l._ a
year was to be Trevithick's share, a portion of which was sold to pay
for the engines. A prospectus drawn up in England states that "the
whole capital was in four hundred shares, of which Trevithick held
eighty, valued at 40,000_l._, together with special advantages to be
accorded to him."

The machinery having left England in September, 1814, reached Peru in
the early part of 1815, shortly after which one of the engines was at
work in the Mint at Lima, within two years from the giving the order
for it in England; for in the early part of the latter year Trevithick
wrote to one of his men:--

 "I am sorry to find by Mr. Uville's letter that the Mint engine does
 not go well. I wish you had put the fire under the boiler and through
 the tube, as I desired you to do, in the usual way of the old long
 boilers, then you might have made your fire-place as large as you
 pleased, which would have answered the purpose, and have worked with
 wood as well as with coal, and have answered every expectation.

 "I always told you that the fire-place _in the boiler_ was large
 enough for coal, but not for wood, and desired you to put it under it.
 The boiler is strong enough and large enough to work the engine thirty
 strokes per minute, with 30 lbs. of steam to the inch. I hope to leave
 Cornwall for Lima about the end of this month, and go by way of Buenos
 Ayres, and cross over the continent of South America, because I cannot
 get a passage; none of the South Sea whalers will engage to take me
 to Lima, they say that they may touch at Lima or they may not, in the
 whole course of their voyage; therefore, unless I give them an immense
 sum of money for my passage, they will not engage to put me on shore
 at Lima, and for me to risk a passage in that way, and to be brought
 back again to England after two years' voyage, without seeing Lima,
 would be a very foolish trip; therefore to make a certainty, I shall
 take the first ship for Buenos Ayres, preparations for which I have
 already made."[126]

[Footnote 126: Unfinished rough draft of letter by Trevithick.]

The whole of the machinery having been sent off, Trevithick was
prepared to make his way across the then little-known continent of
South America in its broadest part, from Buenos Ayres to Cerro de
Pasco.[127] His departure was deferred from various causes until the
20th October, 1816, when he sailed from Penzance in the South Sea
whaler 'Asp,' Capt. Kenny.

[Footnote 127: See Trevithick's letter, December 9th, 1815, vol. ii., p.
31.]

[Illustration: PENZANCE IN OLDEN TIME. [W. J. Welch.]]

  "DEAR SIR,    "PENZANCE, _20th August, 1817_.

 "I am enabled to furnish you with a few particulars which led to the
 introduction of steam-engines into Spanish America, which you will
 embody into your interesting paper for our next Geological meeting, as
 you deem most proper.

 "Captain Trevithick was born in Illogan, Cornwall, 1771, but he has
 generally resided at Camborne, the adjoining parish. He has devoted
 the greatest part of his life to mechanics and to improvements in the
 high-pressure steam-engine, and many engines of Captain Trevithick's
 construction are now working in different parts of England.

 "Mr. Francisco Uville, a native of Switzerland, visited Lima and the
 rich Peruvian mines in the neighbourhood of Lima, at an early age,
 and being a gentleman of great intelligence, he thought it possible
 that the silver mines at Pasco, about 150 miles from Lima, which were
 fast falling into decay for want of machinery to drain the water,
 might be restored to their former celebrity by the introduction of
 steam-engines.

 "Mr. Uville, who is now about thirty-six years of age, came to England
 in 1811, where he continued a few months, and just as he was about to
 leave London he observed by accident a model of a steam-engine, made
 by Captain Trevithick, at the shop of a Mr. Roland, Fitzroy Square,
 and Mr. Uville so much liked the simplicity of its construction, that
 he immediately purchased it at twenty guineas. Mr. Uville returned to
 Lima with it, and tried it on the mountains of Pasco, in consequence
 of which, on the 17th of July, 1812, Mr. Uville, with Don Pedro Abadia
 and Don José Aresmendi, eminent merchants at Lima, were so confident
 of success, that they formed a company to drain the mines at Pasco and
 its vicinity; and on the 22nd of August then following a contract was
 entered into by these gentlemen and the proprietors of the mines in
 that district. Soon after which Mr. Uville was deputed by the company
 to return to England and to find out some able engineer to assist him
 in procuring proper steam-engines to be conveyed to the mines.

 "Uville having put into Jamaica, came to England in the 'Fox' packet,
 Capt. Tilly, and arrived at Falmouth early in the summer of 1813.
 During the passage Mr. Uville frequently talked of the object of
 his voyage, and that he was particularly anxious to find out the
 maker of the model of the engine he took to Lima, and recollecting
 that the name of 'Trevithick' was on the model, he mentioned it to a
 Mr. Teague, who happened to be on board the packet, when the latter
 informed him that Capt. Trevithick was his first cousin, and that he
 resided within a few miles from Falmouth. Immediately on Mr. Uville's
 arrival an interview took place between him and Capt. Trevithick, and
 soon after Mr. Uville removed to Capt. Trevithick's house in Camborne,
 where he resided several months, during which time Capt. Trevithick
 instructed him in mining, machinery, &c.

 "Capt. Trevithick and Mr. Uville, after seeing most of the mines in
 Cornwall, visited several other mining districts in England, to afford
 Mr. Uville a better opportunity of acquiring the best knowledge of
 engineering by examining the steam-engines erected. Afterwards they
 went to London, when Mr. Uville was introduced to a Mr. Campbell, of
 the East India Company's department. Mr. Campbell informed Mr. Uville
 that the best engineers in Europe were Messrs. Boulton and Watt, of
 Birmingham; and strongly recommending them to him, he observed that he
 was convinced if engines could be made capable of being transported to
 the mines of Pasco across the mountains they would be able to do it.
 Mr. Uville accordingly applied to these gentlemen, and fully explained
 to them the nature of the engines which would be wanted, and the state
 of the road by which they must be conveyed, and Messrs. Boulton and
 Watt returned an answer that it would be impossible to make engines
 small enough to be carried across the Cordillera to the mines.

 "Capt. Trevithick, however, was not startled at the difficulties,
 and having applied himself to the improvements of his high-pressure
 engines, entered into a contract with Mr. Uville to provide nine
 steam-engines for the company at Lima; and, by virtue of the powers
 with which Mr. Uville was invested, Capt. Trevithick was admitted a
 partner of one-fifth in the concern; besides which, for his great
 pains and services he had rendered, Mr. Uville guaranteed to him a
 handsome percentage on the profits of the company (_vide_ Articles of
 Agreement of 8th January, 1814).

 "These matters being settled, nine engines were provided at an expense
 of about 10,000_l._, and were shipped on board the 'Wildman,' South
 Sea whaler, Capt. Leith, who sailed from Portsmouth for Lima the 1st
 September, 1814, accompanied by Mr. Uville and the following Cornish
 engineers,--Thomas Trevarthen, of Crowan; Henry Vivian, of Camborne;
 and William Bull, of Chacewater, in Gwennap.

 "The engines arrived at Lima, and were received by a salute from
 the Government batteries, and the greatest joy was testified on the
 occasion.

 "On the 27th July, 1816, the first steam-engine was set to work at
 Santa Rosa, one of the mines of Pasco, under the direction of Mr. Bull
 (_vide_ despatch of that date, signed José G. de Prada).

 "On the 20th October, 1816, Capt. Trevithick sailed for Lima in the
 'Asp,' South Sea whaler, Capt. Kenny, accompanied by Mr. Page, a
 gentleman of London, and James Saunders, of Camborne, an engine maker;
 and on the 6th February, 1817, they arrived at Lima, where Capt.
 Trevithick was immediately introduced to the Viceroy by Don P. Abadia,
 and he received the most marked attention from the inhabitants (_vide_
 'Lima Gazette' of 12th February).

 "Perhaps you will think it proper to notice the furnaces which Captain
 Trevithick took out in the 'Asp' to Lima for the purpose of purifying
 the silver by sulphur. A great expense will be saved by these means.
 Any further information which I can afford you I will readily give.

  "I am, dear Sir,
  "Your very obedient and humble servant,
  "RD. EDMONDS.

 "H. F. BOAZE, Esq."

This statement, from a solicitor more than fifty years ago,
inadvertently points out the difference between the steam-engine of
Watt and that of Trevithick. The former said it was impossible to make
engines having the required power small enough to be carried to the
mountain mines, whereas a small high-pressure engine by the latter had
sufficient power.

Day and Page were lawyers advising Mr. Uville in London. Page sailed
from Penzance with Trevithick and James Saunders, a boiler maker, in
the 'Asp,' a South Sea whaler, on the 20th October, 1816, just two
years after the departure of Uville with the machinery and engines. The
difficulty of conveying heavy weights up the mountain foot-paths was
almost insurmountable.

Mr. Rowe, who went to these mines in 1850, says,--

 "The Cerro de Pasco mines are about 170 miles from Lima; we crossed a
 ridge 25,000 feet high. The mines were about 13,400 feet high above
 the sea. There was but one road; no wheel vehicle could be used;
 everything was carried on mules. Sometimes the road was only 2-1/2
 feet wide, cut in precipices three or four hundred feet perpendicular:
 some of the men were afraid to walk, and dared not ride.

 "I lived in the house that used to be Mr. Trevithick's office and
 store-room; it was in the suburbs of the town of Cerro de Pasco. The
 shafts are some of them in the middle of the town; several pieces of
 Captain Trevithick's engines lay about the shafts, and some on the way
 up, as though they had stuck fast, and some we saw at Lima. Mr. Jump,
 a director on the mine, pointed out a balance-beam that Mr. Trevithick
 had put up thirty years before. Only one Englishman then remained
 there who had worked for Mr. Trevithick; he was called Sycombe, and
 said Trevithick's men were an unmanageable lot.

 "The natives worked in the mines underground. The atmosphere was only
 about 10 lbs. on the inch. We found a coal mine not far off; the
 quality was not very good. The smiths had difficulty in welding with
 it. Our heaviest pieces of machinery did not exceed 280 lbs. The worst
 parts of the road have been a little improved since that time."

Just one month before Trevithick sailed from Penzance for Lima, the
first pumping engine taken out by Uville had been satisfactorily put
to work in the mountain mine of Santa Rosa, with its steam-cylinder
weighing double the limit fixed on by modern engineers.

The following information respecting the progress of the steam-engine
fixed on the Santa Rosa Mines, one of the mineral ridges of Pasco, in
the Viceroyalty of Peru, is extracted from the Government-Gazettes of
Lima, dated the 10th of August and 25th of September, 1816:--

 "PROGRESS OF THE STEAM-ENGINE, &c.

 "_His Excellency the Viceroy of Peru to the Editor._

 "In order to satisfy the eager expectations of the inhabitants of this
 Viceroyalty, those of the greater part of these Americas, and even of
 the Peninsula itself, I hereby order the printing, at full length,
 in the next Government Gazette, or at same time in a separate sheet,
 the enclosed despatch from the Intendant Governor of Tarma, giving
 the details of the admirable results of the steam-engine fixed in the
 mineral territory of Pasco, for the most important purpose of draining
 its mines, and for the extraction of its rich ores. This authentic
 communication must produce the most lively and grateful sensations in
 those true Spaniards, who with grief contemplated as irreparably lost
 the only spring from which flowed the prosperity of this continent,
 excite their just acknowledgments to the meritorious co-operators in
 such an expensive and difficult as well as eminently-advantageous
 enterprise, and encourage to similar undertakings in other parts those
 who, with personal aptitudes and patriotic sentiments, have been
 waiting the final success of the first.

  "JOAQUIN DE LA PEZUELA.

 "LIMA, _4th August, 1816_."

 "_Certificate of the Deputation._

 "We, Don Domingo Gonzales de Castañeda and Don José Lago y Lemus,
 Commissaries and Territorial Magistrates in this Royal Mineral
 Territory, and deputed by the United Corporation of Miners in this
 district, do hereby certify judicially, and as the law directs, in
 manner following:--

"Though this deputation never doubted the extraordinary power of steam
compressed, and consequently the certain operation of engines worked by
its influence, it nevertheless entertained some fears respecting the
perfect organization of all the mechanical powers of the machines. This
uncertainty, rather than any doubt, has been completely dissipated
by our personal attendance this day to witness the draining of the
first pit, situated in Santa Rosa. The few instants employed in the
same produce a full conviction that a general drainage of the mines
will take place, and that their metals will be extracted with the
greatest facility from their utmost profundity: as also that the skill
of the company's partners and agents will easily overcome whatsoever
difficulties nature may oppose, until they shall have completed all
the perpendiculars and levels; and consequently that the meritorious
undertakers who have risked their property in the enterprise will be
rewarded with riches.

"We and the whole Corporation of Miners would do but little were we
to erect them a monument, which should transmit down to the remotest
posterity the remembrance of an undertaking of such magnitude and
heroism; but for the present we will congratulate ourselves that our
labours, co-operation, and fidelity, keeping pace in perfect harmony
with the exertions of the agents, the company may thus attain the
full completion of their utmost wishes, extracting from the bowels of
these prolific mountains, not the riches of Amilcar's inexhaustible
wells, not the treasures of the boasted Potosi in its happiest days,
but a torrent of silver, which will fill all surrounding nations
with admiration, will give energy to commerce, prosperity to this
Viceroyalty and to the Peninsula, and fill the royal treasury of our
beloved sovereign.

"Thus certifies this Magisterial Deputation of Yauricocha, the 27th of
July, 1816.

  "DOMINGO GONZALES DE CASTAÑEDA.
  "JOSÉ LAGO Y LEMUS."

 "_Despatch from the Intendant Governor of the Province of Tarma to His
 Excellency the Viceroy._

  "MOST EXCELLENT SIR,      "PASCO, _27th July, 1816_.

 "Having finally conquered the great difficulties consequent on the
 enterprise, though with immense and incessant labour, and at an
 enormous expense, the object has been accomplished of purchasing,
 importing, and erecting the steam-engine in the celebrated rich and
 royal mineral territory, called 'The Mountains of Yauricocha,' in
 this province of Tarma, of which I have the honour to be Governor,
 the chief and valuable works of which have ceased to produce ore, in
 consequence of their bases being completely submerged in water.

 "The day is arrived when we witness with admiration the advantageous
 and useful effects of the before-named steam-engine; the completion
 of the promises made by the generous and undaunted individuals who
 united themselves to supply the funds sufficient for the realization
 of an enterprise so important, and the fulfilment of the wishes of
 these valuable subjects, to render to the State the highest possible
 service; a service, although at all times of extreme importance, at
 this crisis is infinite; because the State, being weakened by a series
 of disastrous events for six years past, requires salutary remedies;
 and none exist so effectual as the re-establishment of the mines,
 which the steam-engines are achieving.

 "After some experiments, which (although they left no doubt of
 ultimate success in draining the mine) discovered some slight defects,
 these were corrected on the 23rd instant; and this day the first
 of the four pumps which arrived for the use of the royal mines was
 erected in the particular mine called Santa Rosa; the result of its
 operation has been the exhaustion of the water from the well or hollow
 below the adit. In twenty minutes, by this engine, an aggregate of
 water is ejected amounting to 6 yards or 18 feet in diameter, 3 yards
 24 inches in length, and 1 yard 30 inches in breadth. In the same
 manner a second engine, accessory to that which drains the water,
 is worked by the same steam, on the same point, and in the same
 perpendicular shaft, from the surface of the earth, which extracts
 the ore, and with advantages hitherto unknown here, on account of the
 considerable saving of expense and the economy of manual labour.

 "The steam-engine will continue evacuating the water from the pit
 until it is reduced to 6 yards below the old adit, whence they must
 eject the water raised by the engine by a continued elongation of
 the barrel of the pump gaining depth, until they have completed the
 number of yards required, or until the progress of the work indicates
 a proper situation for forming a new line of levels and channels of
 communication to those mines which are not yet drained. In proportion
 to the successive acquisition to these subterranean works which are
 daily advancing, will be the increased operations of the mines, and
 consequently the increased prosperity of the mining interest, which
 had most astonishingly fallen from the degree it had attained in
 former years.

 "In a short time, similar effects will be seen in the three remaining
 mineral ridges of Yauricocha, Caya, and Yanacancha, productive of ores
 of a better quality than that of Santa Rosa, which has nevertheless
 obtained the preference for the erection of the first engine upon it
 from its being more abundant in its peculiar produce, and on account
 of the greater number of persons interested in this property; as
 also its contributing immediately to relieve the necessitous, by
 employing the workmen in the vicinity of the mines. In my opinion, no
 event so beneficial has occurred as the erection of the steam-engine,
 since the discovery and addition of these dominions to the crown of
 Castile. From this time, by the help of these machines, immense and
 incalculable riches will accrue to the nation.

  "God preserve your Excellency many years,
  "JOSÉ GONZALES DE PRADA."

 "_The Viceroy's Answer._

  "LIMA, _5th August, 1816_.

 "Your Lordship's official despatch, No. 898, the 27th of last month,
 communicated to me the satisfactory detail of the complete results
 which you witnessed on the 23rd and 27th, produced by the grand
 steam-engine placed over the mine of Santa Rosa, one of those situated
 in the mountains of Pasco, for the purpose of draining the mine and
 extracting the ores.

 "I desire particularly to distinguish and patronize the chief agent
 and assistant, Don Francisco Uville; the generous promoters of the
 undertaking, Don Pedro Abadia and Don José Arismendi; their agents
 and assistants, Don Luis de Landavere and Don Tomas Gallegos; and
 lastly, Mr. Bull, and all those associated in this great work, whom
 you recommend to my notice. Your Lordship, by having exerted yourself
 to facilitate, by all the means which your zeal and authority could
 procure, the happy consummation of so profitable an enterprise, has
 added a new claim to the many preceding which you possessed, to the
 high consideration of the king and the public.

  "JOAQUIN DE LA PEZUELA,
  "Viceroy of Lima."

 _Extract from the 'Lima Gazette' of the 25th of September, 1816._

 "We have the satisfaction of communicating to the public the
 information that the company for draining the mines of Pasco have just
 received accounts from their agents in that mineral territory; and
 they promise for our next Gazette a description of the state of the
 works for fixing the remaining three engines.--EDITOR.

  "CERRO, _September 20th, 1816_.

 "'After having observed the progress of the machine at the Santa
 Rosa Mine last Saturday, the 14th instant, at 10 o'clock at night we
 began to act; at 11 o'clock the pitmen went down to clear the shaft,
 and have not since ceased working an instant. The clearing of the
 mud and rubbish which had remained at the bottom of the shaft, and
 clogged every moment the buckets and suckers of the engine, lasted
 till Wednesday; but this being accomplished, at 12 o'clock at noon
 they began to break through the level. At half a yard below the shaft
 we found a lively coppery ore, with its particles of silver. This
 bronze-coloured ore indicates that the veins of Yauricocha and San
 Diego incline to the west, or towards the Santa Rosa Mine. The mines
 in the vicinity of this pit are all dry. Some of them, at the distance
 of 300 yards, in the ridge of Santa Rita, have also felt its effects;
 and even as far as the territory of Caya, behind our steam-works, the
 waters have fallen in several mines. Don John Vivas has begun to work
 in San Diego Mine. They are also going next Monday to begin working in
 several points of the Santa Rosa Mine. The pit is already 8 yards in
 depth, and we are proceeding with the greatest activity. The workmen
 are relieved every two hours, and as they go out they give up their
 tools to those who succeed them, by which means not a minute is lost.
 Continuing thus, in the course of a month we shall be at more than 20
 yards depth, and have many mines in full activity. The winding engine
 raises a basket (which is a load) in two minutes; the draining or
 steam-engine, with two vibrations per minute, keeps the surface always
 dry. Both work with the greatest ease, certainty, and regularity.

 "'By dint of searching after a vein of coal, we have at last found one
 near at hand, of excellent quality and of great richness. The pit we
 are now at work at is at the distance of a quarter of a league from
 Rancas, and at the same distance from Vista Alegre which the Cerro is
 from these works. We have likewise found a vein of plumbago, which
 was an object of search, on the supposition that it was coal. This
 substance, of which much is consumed, mixed with grease, to soften the
 friction of the piston, &c., we have now here; and thus the necessity
 of sending to Lima, or perhaps to Europe, for it is obviated.'"

Within six months of the setting to work the pumping engine in Santa
Rosa, another pumping engine was at work at Yanacancha Mine.

The following extracts from the 'Lima Gazette' were published in the
Cornish papers by Mr. Edmonds:--

 "_From the Government Gazette of Lima, 12th Feb., 1817._

 "We have had the pleasure of receiving a letter from Pasco, dated 6th
 instant, containing the following account:--

 "The second engine established in the mine called Yanacancha, which is
 far superior in point of beauty, convenience, and size to that called
 Santa Rosa, was set to work on Friday last, and notwithstanding the
 great quantity of water which filtered into this mine the engine with
 only half its power drained the mine completely in nine minutes. This
 filtration did not happen in Santa Rosa, on account of the quantity of
 hard copper ore on which the engine is situated.

 "By this successful operation, the water in several mines has been
 lessened considerably, amongst which in particular is that belonging
 to Don Juan Vivas, situate in the hill called Chucarillo, which at
 present affords ore of 400 marcos per caxon (50 cwt.). Of this ore
 about 25 lbs. has been received in this city, with a proof of 2 lbs.
 made in Pasco, showing not only the richness of the ore, but its easy
 extraction and cleanness for the ready refinement of it. And another
 proof has also been received from another mine, situate in Chucarillo,
 belonging to the widow Mier, in company with Don Joachin Aitola, which
 yields 100 marcos per caxon of 25 cargas.

 "To this agreeable news we ought to add that at the arrival of the
 whaling ship 'Asp,' bound from London, having on board a large
 quantity of machinery for the Royal Mint, and for the constructing of
 eight engines more, equal to those in Pasco, with the advantage that
 they are of the last patent and more easy to be worked; but what is
 of greater importance is the arrival of Don Ricardo Trevithick, an
 eminent professor of mechanics, the same who directed in England the
 execution of the machinery now existing in Pasco. This professor can,
 with the assistance of the workmen who accompany him, construct as
 many engines as are necessary in Peru, without any need of sending
 to England for any part of these vast machines. The excellent
 character of Don R. Trevithick, and his ardent desire for promoting
 the interests of Peru, recommend him in the highest degree to public
 estimation, and make us hope that his arrival in this kingdom will
 form the epoch of its prosperity, with the enjoyment of the riches
 enclosed in it, which could not be enjoyed without this class of
 assistance, or if the British Government had not permitted the
 exportation from England, which appeared doubtful to all those who
 knew how jealous that nation is in the exclusive possession of all
 superior inventions in arts or industry."

So far everything promised success. Two pumping engines had so reduced
the water in two of the mines, that the miners were at work, and the
people of Lima believed that many more such engines would be usefully
employed, now that Don Ricardo Trevithick was with them.

  "DEAR SIR,      "LIMA, _February 15th, 1817_.

 "We arrived here last Saturday in good health. The (our) Mint is at
 work, and coined five millions last year, and in their way of working
 does very well; but I trust to make it coin thirty millions per year.

 "Two engines are drawing water, and two drawing ore, at the mines, but
 in an imperfect state. If I had not arrived, it must have all fallen
 to the ground, both in their mining and in their engines. I expect we
 shall go to the mines in about ten days, from where I will write to
 you every particular.

 "There are still two engines to put up for lifting water, and two for
 winding ore, and those at work to be put to rights. They are raising
 ores from one mine which is immensely rich, and from what I can learn,
 a much greater quantity will be got up, when the whole are at work,
 than these people have any idea of. Several other mines will also be
 set to work by engines that we shall make here. We have been received
 with every mark of respect, and both Government and the public are in
 high spirits on account of our arrival, from which they expect much
 good to result.

 "Mr. Vivian died the 19th of May. I believe that too much drink was
 the cause of it. Uville, I think, wished him gone, and was in great
 hope that I should not arrive. His conduct has thrown down his power
 very much, which he never can again recover.

 "They all say that the whole concern shall be put entirely under my
 management, and every obstacle shall be removed out of my road. Unless
 this is done, I shall soon be with you in England. I am very sorry
 that I did not embark with the first cargo, which would have made a
 million difference to the company. The first engine was put to work
 about three months since, the other about two months; but they are as
 much at a loss in their mining as in their engineering. The Mint is
 the property of our company, and Government pays us for coining, which
 gives us an immense income; the particulars of which, and the shares
 in the mines, I have not yet gone into. I shall be short in this
 letter, because I know but little as yet, and that little I expect Mr.
 Page will inform you. A full account you shall have by the next ship,
 which I expect will sail in three weeks. This letter goes by a Spanish
 ship that will sail this afternoon for Cadiz. My respects, and good
 wishes to your family and to Mr. Day, and hope this will find you all
 as hearty as we are.

 "Mr. Page would not depart this life under the line, as he promised
 when at Penzance; but, on the contrary, has a nose as red as a cherry,
 and his face very little short of it. His health and spirits far
 exceed what they were in England. I am glad to have such a companion.
 With ... think he will have no reason to repent.... He will get a
 command at Pasco ... such as his ingenuity may find out, when on the
 spot; whether as a miner or an engineer I cannot say, but time will
 show.

 "If you have not insured my life I would thank you to do it now, if
 you can on reasonable terms. I do not wish them to take the risk
 of the seas in the policy, because the voyage here is over, and on
 my return I hope I shall not want it, therefore it must be for two
 years in the country. I will get a certificate of my health, if they
 wish it, from the most respectable inhabitants, and also from the
 Vice-king, if they wish it. The policy may be drawn accordingly.

 "Be so good as to write me often, with all the news you can collect.
 If you wish your dividends in this company to be applied to further
 advantage in any new mines I may engage in, in preference to having
 it sent to England, I will, as the dividends are made, do everything
 in my power to improve the talent. On this subject I must have your
 answer before I can make any new arrangement under this head. I will
 thank you to send a copy of Mr. Page's letter to my wife; I mean such
 parts of it as belong to the business; there may be some things that I
 have forgotten to mention.

  "I remain, Sir,
  "Your humble servant,
  "RICHD. TREVITHICK.

 "MR. JAMES SMITH, _Limekiln Lane, Greenwich_."

In the early part of 1817 four engines were at work in the mines, two
pumping water and two raising the ore; while a fifth engine was coining
in the Mint at Lima. Trevithick believed that he could much improve the
engines and the mining, and that it would be necessary and practicable
to arrange for the construction of engines in Lima; for though death
and dissension had caused difficulty, the authorities were still
prepared to give him full power.

A strange defect in his character is evidenced in this letter. He
wished his life to be insured for the benefit of his wife and family,
but never thought of paying the yearly insurance premium, leaving it
for his wife to pay, whom he had left, as far as he knew, penniless in
England.

On his sailing from Penzance, he told his wife that he had paid the
house-rent for a year in advance, mentioning the sum. At the end of
that time a demand was made on Mrs. Trevithick for a year's rent,
being a larger sum than her husband had mentioned as the proper rent.
It turned out that Trevithick had taken and paid for the house at
six-monthly periods, instead of yearly periods. It was in the same
street, and but three or four houses from that occupied by the parents
of the eminent Sir Humphry Davy.

A person pressed him for payment of a bill. Trevithick said, "Give
me your bill," and writing on the bottom of it "Received, Richard
Trevithick," handed it back to the claimant with "Now, will that do
for you?" The payment of the life insurance obliged Mrs. Trevithick to
part with her personal property, on which she had counted for support
during her husband's absence. This inability to see the necessity of
methodical action, when working with others, and utter disregard for
hoarded money, caused him to be a somewhat unmanageable partner, though
his genius never allowed him to sink; and in November, 1817, he wrote a
letter, of which the following is an extract:--

[Illustration: MARKET, JEW STREET, PENZANCE. [W. J. Welch.]]

 "There are also nunneries beyond number, and in those places no male
 is ever suffered to put his foot. Through one of the most noted runs
 a watercourse, which works the Mint; and Mr. Abadia has repeatedly
 made all the interest he could to be admitted, for the purpose of
 inspecting it, but could never get a grant. The Mint belongs to our
 engine concern, and now coins about five millions per year. We have
 a contract from Government for making all the coin, both gold and
 silver, which gives an immense profit; and as there must now be coined
 six times as much as before, I must build new water-*wheels to work
 the rolls which we took with us from England. It was on this account
 that I wished to examine the watercourse for this purpose, without the
 knowledge of Mr. Abadia or anyone but Mr. Page and the interpreter,
 who always attends me. I walked up and knocked, in my blunt way, at
 the nunnery court door, _without knowing there were any objections to
 admit men_; it was opened by a female slave, to whom the interpreter
 told my name and business. Very shortly three old abbesses made their
 appearance, who said I could not be admitted. I told them I came from
 England, for the purpose of making an addition to the Mint, and could
 not do it without measuring the watercourse; upon which a council
 was held amongst them; very soon we were ordered to walk in, and
 all further nunnery nonsense was done away. We were taken round the
 building and were shown their chapel and other places without reserve.

 "Uville knew nothing about the practical part of the engines, and Bull
 very little, therefore you may judge what a wretched state this great
 undertaking was in before my arrival; no one put any confidence in
 it, and believed it was all lost, together with five hundred thousand
 dollars that had been expended on it. The Lord Warden was sent from
 Pasco to offer me protection and to welcome me to the mines. They have
 a court over the mines and miners, the same as the Vice-Warden's Court
 in England, only much more respected and powerful. The Viceroy sent
 orders to the military at Pasco to attend to my call, and told me he
 would send whatever troops I wished with me. The Spanish Government
 and the Vice-king since my arrival are quite satisfied that the mines
 will now be fully carried into effect, and will do everything in their
 power to assist me. As soon as the news of our arrival had reached
 Pasco, the bells rang, and they were all alive down to the lowest
 labouring miner, and several of the most noted men of property have
 arrived here--150 miles. On this occasion the Lord Warden has proposed
 erecting my statue in silver. On my arrival Mr. Uville wrote me a
 letter from Pasco, expressing the great pleasure he had in hearing
 of my arrival, and at the same time he wrote to Mr. Abadia that he
 thought Heaven had sent me to them for the good of the mines. The
 water in the mines is from four to five strokes per minute.

 "Tell the members of the Geological Society that Mr. Abadia is making
 out a very good collection of specimens for them, which will be sent
 by the first opportunity; and soon after I arrive at Pasco I will
 write them very fully."

After Trevithick's death, in 1833, casts were taken from the head, and
busts presented to scientific societies were thankfully received, with
the single exception of his near neighbours at Penzance, who, under the
name of the Royal Geological Society of Cornwall, refused it.

Mr. W. J. Henwood, who had frequently drawn the attention of Cornishmen
to Trevithick's engines, being about 1870 President of the Royal
Institution of Cornwall, presented to it a bust of Trevithick, which
was admitted within its walls.

In 1819 Mr. R. Edmonds forwarded to the 'Cornwall Gazette' news from
Lima, from which the following is extracted:--

 "We have much pleasure in stating that accounts have lately reached
 England from Lima, giving the satisfactory intelligence that our
 countryman and able engineer, Captain Trevithick, was in February last
 in good health, and super-*intending the rich and extensive mines of
 Pasco.

 "Don Francisco Uville, a Spanish gentleman, having, with Don Pedro
 Abadia and others, formed a company to drain the mines of Pasco,
 unfortunately for Captain Trevithick, F. Uville was anxious to impress
 his countrymen with an opinion that it was _solely_ owing to him
 that steam-engines were first introduced into the silver mines of
 South America; and notwithstanding the obligations he was under to
 Captain Trevithick, he sought every opportunity, soon after Captain
 Trevithick's arrival at Pasco, to oppose him, in claiming to have the
 direction of the mines.

 "Captain Trevithick, knowing but little of the country, and disgusted
 with the treatment he received from Uville and the party he had formed
 against him, amongst whom was a gent who had lately arrived from
 England, retired from the concern, and proceeded on other important
 discoveries on his own account.

 "Things remained in this state until August, 1818, when Uville met his
 death, in consequence of the cold penetrating air of the Cordilleras
 on coming out of the mines in a strong perspiration. Mr. Abadia and
 his friends were then under the necessity of soliciting the assistance
 of Captain Trevithick. On condition of his having the sole direction
 of the mines, he was prevailed upon to accept the situation which
 had been first most faithfully agreed he should have had; and when
 the accounts last left Lima in February, Captain Trevithick had been
 five months at the mines as the chief superintendent. The mines are
 represented as being in the most prosperous state, and likely to
 realize the sanguine expectations of the share-*holders. Mr. Bull, an
 engineer from Chacewater, who left England with Uville, died at Pasco
 about ten months since."

When this was written, Trevithick had been two years in the country,
and found the immense difficulties of the undertaking increased by
jealousies and jobberies. Mr. Uville was no more, neither were Vivian
or Bull; but one man remained alive out of the four who had sailed from
England with the first cargo of machinery. In August, 1818, Mr. Abadia,
who from the first was a leading authority, requested Trevithick to
take upon himself the sole management of the mines, where he continued
until April, 1819, as shown by the following extract from Captain
Hodge's journal, supplied by my friend Mr. Charles Hodge:--

 "The first time they met was at Lima, on the 26th April, 1819, at
 Dr. Thorne's; your father had just come down from the Cerro de Pasco
 mines. On the 8th May following, I find my father witnessed the
 hanging of three men for killing two of your father's men, named
 Judson and Watson."

Mr. W. B. Stevenson says:[128]--

[Footnote 128: See 'Historical and Descriptive Narrative of Twenty Years'
Residence in South America,' by W. B. Stevenson, published 1842.]

 "The Mint was established in Lima, in 1565. The machinery was formerly
 worked by mules, eighty being daily employed till the year 1817, when
 Don Pedro Abadia, being the contractor for the coinage, Mr. Trevithick
 directed the erection of a water-wheel, which caused a great saving
 of expense. In the year 1817 two Englishmen, sent from Pasco by Mr.
 Trevithick (who afterwards followed with the intention of working some
 of the silver mines in Conchucos), were murdered by the guides at a
 place called Puloseco. This horrid act was perpetrated by crushing
 their heads with two large stones, as they lay asleep on the ground.
 The murderers were men who had come with them from Pasco.

 "I have heard Mr. Trevithick say, that on shaking hands with the men
 who work in those quicksilver evaporating rooms, drops of quicksilver
 show themselves at the fingers' ends, and that the workmen wearing
 shoes take them off before leaving the work, to pour out any
 quicksilver that had oozed through the pores of the skin, which had
 been respired in the floating state of vapour. The men so employed
 fell a sacrifice in twelve or eighteen months."

Trevithick's experience in applying the force of running streams
was turned to good account in giving an economical helpmate to the
steam-engine then at work in the Mint. Miers says:[129]--

[Footnote 129: See Miers' 'Travels in Chili and La Plata,' published
1826.]

 "Another instance occurs in the unfortunately ruinous result and
 lamentable ill-treatment of the persons engaged in the attempt to
 introduce European improvements and British machinery into the great
 silver-mining district of Pasco (Chili), in which was engaged one
 of our most celebrated engineers, a most able mechanic, to whom the
 grand improvements in our Cornish mines are chiefly indebted--I
 mean Mr. Richard Trevithick. Trevithick was induced to furnish the
 machinery at an expense of 3000_l._ sterling, upon condition of being
 admitted a partner in the amount of 12,000 dollars in the joint stock
 of the company, and entitled to a share corresponding to the capital
 employed. This share was calculated at a fifth. Trevithick, before
 he embarked for Peru, divided his interest in the concern into 320
 shares, each representing 38 dollars, and these were sold in the
 market for 125_l._ sterling each; some few were sold for 100_l._ cash.
 The success of the engines gave to some of the persons interested much
 confidence, who conceived they could now do without the management
 of the ingenious Trevithick. Every possible obstacle was therefore
 thrown in his way by those who, from motives of jealousy, wished to
 get rid of him. The persons to whom Trevithick's and other shares had
 been sold in London, sent out to Lima an agent, whose duty it was
 to look after their interests in the concern; but as it was found a
 much larger sum would be necessary for carrying the enterprise into
 effect than had been calculated, a collision of interests took place;
 complaints were made on all sides as to the delays and expenses which
 those who did not comprehend the almost insurmountable difficulties
 of the undertaking attributed to mismanagement and carelessness. The
 greatest share of opprobrium fell unjustly upon Trevithick, who,
 being a man of great inventive genius and restless activity, was at
 length completely disgusted, and retired from the undertaking. He left
 Pasco, although Abadia offered him 8000 dollars per annum, together
 with all his expenses, if he would continue to superintend the works;
 on no conditions would he consent to contend with the jealousies and
 ill-treatment of the persons with whom he had to deal. He soon after
 entered into speculations with some of the miners at Conchucos, for
 whom he constructed grinding mills and furnaces, with the view to
 substitute the process of smelting for that of amalgamation in silver
 ores, in which vain pursuit he became a considerable loser."

  "MY DEAR SIR,      "BODMIN, _November 3rd, 1869_.

 "Forty-seven years are now passed since I had the great pleasure of
 meeting your father in Peru, and I have a vivid remembrance of the
 gratification afforded to my messmates when he came to dine with us on
 board H.M.S. 'Aurora,' then lying in Callao. I was then a lieutenant
 of that beautiful frigate, and was introduced to your father by Mr.
 Hodge, of St. Erth, with whom I had become acquainted in Chili. I
 remember your father delighting us all on board the 'Aurora' by his
 striking description of the steam-engine, and his calculation of the
 'horse-power' of the mighty wings of the condor in his perpendicular
 ascent to the summit of the Andes. Your father's strong Cornish
 dialect seemed to give an additional charm to his very interesting
 conversation, and my messmates were most anxious to see him on board
 again, but he left shortly after for the Sierra.

 "The Pasco-Peruvian mines were those which your father was engaged
 to superintend before he left England, and he had actually managed,
 by incredible labour, to transport one or two steam-engines from the
 coast to the mines, when the war of independence broke out, and the
 patriots threw most of the machinery down the shafts. This fearful
 war was a deathblow to your father's sanguine hopes of making a rapid
 fortune. About a year after this terrible disappointment (I think in
 1822), the 'San Martin,' an old Russian fir frigate, purchased by the
 Chilian Government, sank at her anchors in Chorillos Bay, ten miles
 south of Callao, and your father entered into an engagement with the
 Government in Lima to recover a large number of brass cannon, provided
 that all the prize tin and copper on board which might be got up
 should belong to him. This was a very successful speculation, and in
 a few weeks your father realized about 2500_l._ I remember visiting
 the spot with your father whilst the operations were carried on, and
 being astonished at the rude diving bell by which so much property
 was recovered from the wreck, and at the indomitable energy displayed
 by him. It was Mr. Hodge, and not I, who then urged in the strongest
 manner that at least 2000_l._ should be immediately remitted to your
 mother. Instead of this, he embarked the money in some Utopian scheme
 for pearl fishing at Panama, and lost all!

 "I had the honour of dining with Lord Dundonald on board the crazy
 frigate 'Esmeralda,' which carried his flag in Callao Bay, but I never
 heard of the gallant conduct of your father in swimming off to his
 ship and advising him of an intended assassination. I fancy that this
 must have occurred before I came on the station, probably in 1820, or
 1821.

  "Believe me,
  "My dear Sir,
  "Very sincerely yours,
  "JAMES LIDDELL."

Trevithick's floating caissons for the sunken ship of Margate Bay in
1810[130] were similarly applied in 1821 in the Bay of Callao. In Lima he
became acquainted with Lord Dundonald, whom he warned of a plot on his
life, discovered in his friendly intimacy at the residence of President
Bolivar. Those two remarkable Englishmen were alike in their daring
inventiveness, and not unlike in face and person.

[Footnote 130: In 1834 the writer was employed at a marine engine works
in London, and made working drawings for a scheme of Lord Dundonald's,
who expressed great pleasure in meeting the son of his old friend.]

We have traced Trevithick's steps from his landing at Lima in 1817
to the destruction of the mine machinery by the civil wars, and his
departure from there about 1822. But one link in the chain has been
nearly lost. During some portion of those five years he visited Chili,
and set to work mines which are still producing large and profitable
quantities of copper. The late Mr. Waters, an eminent Cornish miner,
who for many years managed some of these mines in the neighbourhood of
Valparaiso, said that Trevithick's name was better known to the miners
there than to the miners in Cornwall. This statement was made in the
Dolcoath account-house at a public meeting, the speaker and the writer
being both on the committee of management.

Simon Whitbarn, of St. Day, informed the writer that at Copiapo and at
Coquimbo he had seen large heaps of copper ore, apparently unclaimed,
which the people said had been raised by Don Ricardo Trevithick. About
1830 a miner, returned from South America, made a claim for wages for
watching mineral left behind by Mr. Trevithick.

To further illustrate this history, we have a report written by
himself:--

 "_Memoranda regarding the Copper and Silver Mine of * * * *._

 "In 1814 an arrangement was made between the miners of Peru and myself
 for furnishing them with nine steam-engines and a mint, to be executed
 in England and erected in the mines of Pasco; and in October, 1816,
 I sailed from England for that country, for the express purpose of
 taking the management of those mines and erecting the machinery, being
 myself a large proprietor of the same. The Government of Peru was at
 that time subject to old Spain, under the immediate superintendence
 of a Viceroy. The machinery having been erected, and its sufficiency
 for the intended purpose of draining the mines having been proved to
 the satisfaction of all parties, there was granted to me a special
 passport by the Viceroy, for the purpose of travelling through the
 country to inspect the general mining system, and to make the native
 miners acquainted with the English modes of working. In return for
 which Government conceded to me the privilege of taking possession for
 my own benefit and account of such mining spots as were not previously
 engaged. In this way I travelled through many of the mining districts,
 and although I met with several unoccupied spots which would have
 paid well for working, yet, being a considerable distance inland, and
 requiring more capital to do them justice than I could then advance, I
 abandoned for the time all ideas of undertaking them.

 "To this, indeed, there was but one exception, and that was a copper
 and silver mine, the ores of which are uniformly united, in the
 province of Caxatambo.

 "When the patriots arrived in Peru, the mine was deserted by all the
 labourers, in order to avoid being forced into the army. In this state
 it remained for a considerable time; but on the Spaniards retreating
 into the interior, I recommenced working; and to secure my right to
 this mine under the new Government I at the same time transmitted a
 memorial and petition to the established authorities, accompanied by a
 plan and description of the mine, the result of which was the formal
 grant, as exhibited in the Spanish document now in your possession.
 It was not my good fortune to be allowed to follow up my plans, which
 almost warranted a certainty of success. I had scarcely commenced
 a second time when the Spaniards returned, and everyone again was
 obliged to fly. The country, as is well known, continued for a long
 time in a most distracted state, and I was ultimately compelled to
 quit that part of Peru, robbed of all my money, leaving everything
 behind me, miners' tools and about 5000_l._ worth of ores on the spot
 ready to be carried to the shipping port. Numerous as my misfortunes
 had been in Peru, and heavy as my disappointments, I felt none so
 sensibly as this, because it was an enterprise entirely of my own
 creation, and so open to view that I was enabled to calculate at a
 certainty the immense value contained within the external circle where
 the copper vein made its appearance in the cap of the mountain, and
 to be obtained without risk or capital. However, revolution followed
 revolution, and the war appeared to me to be interminable. Even
 Bolivar's arrival at Lima made it still worse, for he forced me into
 the army, with my property, which is not paid to this day, to the
 amount of $20,000; and at his urgent solicitations, disgusted as I was
 with what I had seen and suffered in Peru, I determined on quitting
 it for a time at least, and on visiting Colombia. Being at Guayaquil
 I first heard the name of Costa Rica and its recently-discovered
 mines, and having no doubt of the authenticity of my information,
 I immediately proceeded thither instead of going to Bogota to
 carry Bolivar's orders into execution, not having been paid. This
 short digression you will excuse, as it points to the causes of my
 separation from a property of so much value, as I consider the mine of
 * * * * *. Thirty years ago the neighbourhood of * * * * was famous
 for its silver mines. At the foot of the copper hill, on a fine
 stream, are two sets of works on a most extensive scale, which were
 carried on on account of the Spanish Government. The silver was found
 in lead veins, which are very large and numerous all around. The soil
 is very rich, and the climate as good as any in the world, wheat and
 Indian corn both growing round the mountain. Provisions and wages are
 low, the latter 1_s._ per day, and there are about 20,000 inhabitants
 within three miles. Wood for smelting and other purposes is abundant
 on the spot.

 "* * * * is * * leagues from Lima; the port of * * * * where the
 ores are to be shipped, is 37 leagues north from Lima; and * * * *
 copper mine * * leagues back in the country east from this port, a
 good road for mules and plenty of them. The miners contracted with me
 to break the ores and deliver them at the surface for 4_l._ per ton,
 which was double what I ought to have paid them; the farmers likewise
 contracted to carry the ores to the port at the same rate, which
 comes to sixpence a league for each mule cargo. But even at present
 wheel-carriages might travel over a large proportion of the road, and
 a small outlay would make it a carriage-road the whole distance, and
 then the expense of carriage would be diminished more than one-half.
 Taking it, however, at what it cost me, the whole expense on the ores
 delivered on board would not amount to 9_l._ a ton, and as I conceive
 the freight to England would not exceed 4_l._ a ton, the total cost
 would be 13_l._, but say 15_l._ a ton. Its value in England would be
 above 80_l._ a ton. At the time I worked I intended to have sent 300
 tons of ore to England, for in the then disturbed state of the country
 it would not have been prudent to risk myself on smelting works. I
 think it will ultimately be found preferable to smelt on the spot, but
 the course I should recommend in the meantime would be to send out two
 practical miners to direct and superintend the natives, who ought to
 be employed by contract to break and raise the ores and deliver them
 on board. In that case no erections whatever would be wanted; nothing
 but about 70_l._ worth of labourers' tools.

  "I remain, Sir,
  "Your very humble servant,
  (Signed) "RICHARD TREVITHICK."

The foregoing undated report was written after his return to England
from South America. The Viceroy granted him a special passport through
the country, that he might give general instructions to the workers of
mines, with the right to claim any mineral spot for his own working not
under grant to others.

He often spoke of his discovery and working of the great vein of
copper ore in Caxatambo, estimated to contain copper worth twelve
millions sterling, the working of which was prevented by the frequent
revolutions and unsettled government of the country; and of residing
for months with Bolivar, at that time the Republican Governor of Peru.

Bolivar's cavalry were short of fire-arms. Trevithick invented and made
a carbine with a short barrel of large bore, having a hollow frame-work
stock. The whole was cast of brass, stock and barrel in one piece,
with the necessary recess for the lock; the bullet was a flat piece
of lead, cut into four quarters, held in their places in a cartridge
until fired, when they spread, inflicting jagged wounds. He was obliged
to serve in the army, and to prove the efficiency of his own gun. He
was never a good shot, nor particularly fond of shooting; and, after a
long time, Bolivar allowed him to return to his engineering and mining.
Scarcely had he got to work again when the Royal Spanish troops,
getting the best of it, overran the mines, and drove Trevithick away
penniless, leaving 5000_l._ worth of ore behind him ready for sale.

The 300 tons of ore, valued at 24,000_l._, never reached England; and
the writer, who was to have returned to Peru in the ship that had been
engaged to convey it, lost the chance of being a youthful traveller in
foreign lands.

Trevithick left Lima about 1821 or 1822, for Bogota, in Colombia, on a
special mission for Bolivar. On his way, putting in at Guayaquil, he
heard of rich mines in Costa Rica, and thinking they would pay better
than Bolivar's promises, he threw up his engagement and made for the
new venture. It was probably at Guayaquil that he met Mr. Gerard, a
Scotchman of good family and education, then sailing on the Pacific
coast as a speculator.

Since Trevithick left the mines of Cerro de Pasco, more than one
English adventurer has attempted to work them. At the present time they
are in the hands of a large company, and are thus spoken of in the
'Cornish Telegraph' of May 10, 1871:--

 "_Cerro de Pasco and its Silver Mines._

 "This place, in the Republic of Peru, is situated on the top of the
 Andes, on the eastern side of the Western Cordillera. It stands about
 15,000 feet above the sea level, and is said to be one of the highest,
 if not the highest, inhabited place of importance in the whole world.

 "From Callao to here is a distance of 160 miles, but, in consequence
 of the rapid ascent in such a comparatively short distance, it is
 considered a quick journey if mules make it in six days; it more
 frequently takes them a week, and at times, during the season of snow
 and rain, the pampas, which are the table-lands of these mountains,
 are impassable for several days together.

 "The town of Cerro de Pasco, which at present numbers 10,000 souls,
 is of no small importance, considering its great altitude and
 inconvenient distance from the coast, but it lacks order and design
 in every part. The streets are crooked and uneven; and the houses are
 stuck about anywhere and everywhere, with the greatest display of
 uneducated taste that I have ever before witnessed; moreover, it would
 be difficult to find another such place so equally dirty.

 "It rains and snows on these heights with not much cessation for about
 six months in the year, and in what is termed the dry season there are
 also frequent falls of snow. Furthermore, water boils at 180° Fahr.
 instead of at 212°, as with you; consequently it requires six minutes
 to cook an egg.

 "The majority of the inhabitants are a low type of Indians, who
 are small in stature and mind, but are large in cunning, and have
 exceedingly plain features--not possessing the slightest trace of the
 noble features and bold simplicity of the Indians of the North.

 "Any person acquainted with minerals and mining coming up to Cerro
 de Pasco would fancy that the whole town was built on the back of
 one huge lode; go wherever one may, through the streets, or on
 the outskirts of the town, and even up to the slopes of the hill
 surrounding it, he finds it to be all lodestuff everywhere; its
 composition is what we Cornish miners generally term an iron gossan.

 "The greater portion of this mineral spot is parcelled out into setts
 or grants, which consist of pieces of ground 60 yards in length by 30
 in width, giving to the place no less than 664 mines. At present there
 are no more than seventy-eight of them at work, and only sixty-three
 of which are producing ore, and the united returns amount to 2,000,000
 oz. of silver per annum. Owners or companies have roads leading down
 to their mines, formed of steps cut out in the rock, dipping at angles
 varying from 30° to 50°. When you have descended to the depth of the
 mines, the levels or holes leading to many of them are so small that
 one has to drag himself along snake fashion until he reaches the main
 excavation. The miners break down the silver ore with pointed bars of
 iron, and then shovel it into bags made of hide with the shoulder-bone
 of some animal; after which the stuff is carried to surface on men's
 and boys' backs.

 "When all the mineral has been extracted there remains an immense
 excavation, and in consequence of the roof not being properly
 supported with timber, one risks his life in entering it. Heavy falls
 of rock frequently occur, and by which means a vast number of persons
 are annually killed. One day in the last century, at the mines of
 'Matagente' (which word means killed people), which are situated in
 the rising ground on the northern side of the town, while a great
 number of men and boys were at work, the roof of one of these immense
 chambers, consisting of many thousands of tons, fell in without giving
 the least warning, and 'in the twinkling of an eye' the souls of 300
 Peruvian miners rushed into the presence of their Redeemer. Their
 bodies have never been exhumed, and their shattered bones, still
 remaining, will bear evidence of the catastrophe to future explorers.
 An adit has been driven through the district, beginning at the Lake
 of Quiulacocha on the south-west, and terminating at the mines of
 Ganacaucha on the north. The entire length of the adit, including
 its branches, is about 3 miles, and its average depth from surface
 50 fathoms. Three perpendicular shafts, situated at about 600 yards
 apart, have also been sunk from surface to a short distance below the
 adit.

 "The whole of the machinery for the mines in question, which is being
 made and dispatched by Messrs. Harvey and Co., of Hayle, Cornwall,
 consists of four steam pumping engines, six boilers, four iron main
 beams, four balance ditto, and also a sufficient quantity of 24-inch
 pit-work for both shafts. No single piece of all this cumbrous
 machinery must weigh more than 300 lbs., in consequence of its having
 to be transported on the backs of mules from the coast to this
 mountainous region. Although the main distance is no more than 160
 miles, these beasts with their burdens have to climb an altitude of
 15,000 feet before they reach their destination. Moreover, the passes
 in ascending the Andes and Cordillera can only be correctly imagined
 by experienced travellers. Some of the defiles are not much wider than
 a sheep-path, and with a thousand feet below you a roaring cataract,
 and thousands of feet above you snow-capped overhanging mountains,
 looking so dreadful that the awe-struck stranger in the pass fears
 that the next peal of thunder will cause them to topple."

[Illustration: MULE TRACK FROM LIMA TO CERRO DE PASCO. [W. J.
Welch.]]

 "I observe in a paper which is now before me, entitled 'The
 Introduction of the Steam-Engine in the Peruvian Mines, by Richard
 Trevithick, in 1816,' that when Captain Trevithick arrived at Lima
 on board the ship 'Asp,' with sundry small engines for the draining
 of the mines of Cerro de Pasco, he was immediately presented to the
 Marquis de Concordia, then Viceroy of Peru, was most graciously
 received by the most flattering attention of the inhabitants, and
 subsequently the Viceroy ordered the Lord Warden of the mines to
 escort the great man with a guard of honour to the mining district.
 In contrasting the two epochs, that of Trevithick in 1816, with this
 of Wyman and Harrison in 1871, one is led to exclaim that there were
 _gentlemen_ in Peru in 1816, and they gave unto Cæsar that which
 belonged to Cæsar."[131]

[Footnote 131: In 'Mining Journal,' W. R. Rutter.]

The same newspaper, on the 9th November, 1870, stated:--

 "The 'Bride' sailed from Hayle on Thursday with a portion of the
 machinery made by Messrs. Harvey and Co., of Hayle, destined for Cerro
 de Pasco, in Peru. The work comprises four 37-inch cylinder pumping
 engines; no part to weigh more than 300 lbs."

To enable the parts to be reduced in weight, each steam-cylinder was
made of thirty-seven different pieces. The mechanics of Trevithick's
time could not make a steam-cylinder in parts; therefore his
difficulties in designing and conveying the machinery were ten times
greater than they would be in the present day, and necessitated the
extreme simplicity of his engines. His residence with the Peruvians
from 1816 to 1822 taught them the use of high-pressure steam-engines in
their mines; and indirectly heralded the advent of the steam-horse, now
as familiar to them as to the residents in many English towns.




CHAPTER XXIII.

COSTA RICA.


  "MY DEAR SIR,

 "In the month of June, 1822, I disembarked in the port of Punta de
 Arenas, in the Gulf of Nicoya, the only one corresponding to that
 province at present in use on the Pacific side. My object was to
 dispose of a cargo of cotton which I had brought from Realejo, and to
 purchase sugar in return. Circumstances, not necessary to mention,
 and the loss of the small vessel with which I was trading on the
 coast, caused me to remain in Costa Rica. Its name implies a very
 early conviction of its natural opulence; it is certain that gold
 and silver abounded among the Indians at the period of its conquest
 by the Spaniards. It was at one time a favoured and flourishing
 agricultural colony, but from various causes sank into neglect. Such
 was the apathy, both of the Government and of individuals, that the
 very existence of the precious metals in the country had been almost
 entirely forgotten. In the end of 1821, a poor man, Nicolas Castro
 by name, opened the first gold mine known in Costa Rica since the
 conquest, and his success soon induced others to try their fortunes;
 with fortunate results, in a few months a mining district sprang into
 being.

 "A gentleman of the name of Alverado constructed at a very
 considerable expense what is called an Ingenio, consisting of
 various edifices for depositing the ore, machinery driven by water
 for grinding it and afterwards blending it with quicksilver for
 amalgamation.

 [Illustration: PLATE 14.

 London: E. & F. N. Spon, 48, Charing Cross. Kell. Bro^s Lith. London.

 TREVITHICK'S ROUTE ACROSS THE ISTHMUS OF COSTA-RICA.]

 "When I landed in June, 1822, only five or six mines had been
 discovered, but in January 1823, when I left the country, I cannot
 pretend to enumerate those in a state of progress and of promise.
 It is not only in the mining part of the business that the
 want of skill is prejudicial to the result. It is imperfectly
 ground, for instance, and consequently cannot be brought into that
 intimate contact with the quicksilver which is necessary to perfect
 amalgamation. The machine for grinding is very simple: a large flat
 stone, like a mill-stone, is made to revolve upon its fellow by an
 ox or mule power. The poorest people reduce it to powder by manual
 labour, in the same way as they grind corn preparatory to baking it
 into cakes. Alverado's machine promised to be a great acquisition. The
 grinding was facilitated by a little water; when the ore is judged to
 be sufficiently well ground, a portion of quicksilver is thrown in
 by guess, and the motion of the machine continued until the union of
 the metals is supposed to be complete; the whole is then removed into
 large wide-mouthed conical-shaped wooden vessels. In these receptacles
 it undergoes repeated washings, by stirring occasionally round, and
 afterwards communicating to the vessel a swinging or half-rotary
 motion, by which a quantity of the water, having the earthy particles
 suspended, is driven over the edges; the amalgamated mass naturally
 sinks to the bottom, and at last remains tolerably clean.

 "The next step is the recovery of the quicksilver by distillation,
 after which the gold is melted in a crucible and run into ingots. The
 coasts are hot, and from the luxuriant vegetation that everywhere
 abounds, emit, as in all situations of the kind, febrile miasma
 in abundance when acted on by heat and moisture; but black vomit
 is unknown, and all the fever cases I have seen have been of the
 remitting and intermitting, free from character of malignancy. As the
 ground begins immediately to spring from the coast, and does so indeed
 very rapidly, a few miles takes us beyond the region of even these
 slight fevers, and as we continue ascending to the central table-land,
 a climate is encountered that may vie with any in the world for
 benignancy and beauty. We there meet with the fruits of the torrid
 zone, and near them the apple and the peach of Europe. The orange
 tree is in bearing the whole year. As in all situations within the
 tropics, it has a proper rainy season, but it is less inconvenient and
 disagreeable than might be expected, for it seldom rains two days in
 succession, and when it does, is invariably succeeded by an interval
 of fine weather; for the most part every day presents a few dry hours.
 The mines are situated on the ridges of the Cordillera, which without
 presenting snow-covered peaks, attain, nevertheless, considerable
 elevation. The clouds, constantly attracted by those high summits,
 render the rainy season more severe in the mining district than in the
 plains. The greatest inconvenience was from the snakes, which in those
 solitary jungles, now first invaded by man, are very numerous and many
 of them venomous. Provisions are cheap and excellent. In short, there
 is but one fault I find with the country, and it is a great one, I
 mean the frequency of earthquakes.

  "J. M. GERARD."

 MEM. IN MR. GERARD'S WRITING.

 "_Illustrations of the Map._

 "Though the plans and sections explain themselves, a few observations
 will not be misplaced. The deep adit for the Coralillo would be 600
 yards, that for Quebrada-honda 400 yards, and besides serving as
 drains would form admirable roads for conveying the ores into the vale
 where the stamps must be erected.

 "The veins would be worked upward from the adits, and thus no expense
 would be incurred for ages to come in lifting either water, ore, or
 rubbish to the surface. Padre Arias Mine is an exception, requiring a
 powerful water-wheel, or an hydraulic pressure-engine, for which there
 is a fine fall of water of 135 feet. The mines in Quebrada-honda are
 those in which an interest has been procured. Captain Trevithick has
 an interest in the mine of Coralillo; the great watercourse is also
 his.

 "It will be seen by the plan that there are 75 fathoms fall to the
 point where his present mill is situated, and other 75 fathoms to
 the junction of the rivers of Quebrada-honda and Machuca. The whole
 length does not amount to two miles, within which it is estimated
 that sufficient power may be commanded to stamp 500,000 of quintals
 annually. To bring it up to that pitch, the waters of Machuca must be
 brought to join those of Quebrada-honda at Trevithick's mill, and
 then 40 tons of water per minute could be delivered in the dry season."

Extracts from a report by Trevithick and Gerard in 1827:--

 "This map consists of several distinct parts. The middle part shows
 the mining district, the present dimensions of which are small, the
 length being hardly four miles, breadth from two to three, and the
 superficial extent from eight to ten miles. The upper part of the plan
 is a section of the north ridge, called Quebrada-honda, and shows the
 line of the proposed adits. The lower part in like manner exhibits the
 south ridge, called Coralillo. The map further shows the inclination
 or gradual fall of the ground along the valley, and of the streams by
 which the mills are driven.

 "The canal is likewise shown 5000 yards in length, by which the rivers
 of Machuca would be brought to join that of Quebrada-honda.

 "Castro's mine is situated on the southern ridge, and was the first
 mine worked to any extent. There the veins are very large; in fact,
 from the manner in which a number of horizontal veins are seen falling
 into the perpendicular or master vein, the great body of the mountain
 would appear to consist of lodes. This mass of ore is in general
 rich. It has been worked open to the surface, somewhat like a quarry,
 so that it is not difficult to calculate in cubic feet the quantity
 that has been excavated. The mine is supposed to have yielded in the
 course of the last six years gold to the value of 40,000_l._, and by
 measuring the excavations it would appear that this amounts to, on
 an average, one ounce of fine gold to every ten or twelve quintals
 of ore. In 1821 the existence of silver was only imagined. In 1823
 it was fully ascertained. Ever since 1824 it has constituted a small
 but constant portion of the produce of Quebrada-honda, and in 1827
 it was decidedly evinced in Coralillo. The discovery of gold in
 Coralillo led them to work in Quebrada-honda, where they found both
 gold and silver, and the discovery of silver in Quebrada-honda, by
 strengthening the expectation of it in Coralillo, led in its turn to
 the discovery of silver there. In Quebrada-honda they only work on
 the ground in the immediate vicinity of the stream, and that in the
 most imperfect manner; but great light has been thrown on the value of
 the ores on this spot and in the district generally by the progress
 made in working what is called Padre Arias Mine, which takes its name
 from an ecclesiastic who first worked it. This mine is situated in
 low ground near the verge of the stream, and was at first only worked
 for gold. There were soon, however, indications of silver, which
 increased progressively in sinking, till at the depth of only 10 yards
 the influx of water exceeded the means of draining, and the works
 under water-level were necessarily abandoned, at a time when ores were
 yielding upwards of 200 oz. of silver to the ton, a striking proof of
 the tendency of silver ore to improve in this district as the depth
 increases.

 "Mr. Richard Trevithick, that eminent Cornish miner and engineer, so
 well known for his inventions, and particularly for the high-pressure
 steam-engine and the drainage of the Pasco Mines in Peru, when
 unfortunately civil war burst out in Peru, and the Royalists,
 considering those engines as the main instrument for supplying money
 to the Independents, rendered them useless by destroying or carrying
 off some of the most important pieces.

 "Mr. Trevithick having heard favourable reports of the mining district
 we are now describing, soon after repaired thither, and was so fully
 impressed with its value and importance that he made an extensive
 contract for different properties, and resided in the country for four
 years.

 "He is now in England ready to give explicit answers to any inquiries
 that may be made as to the mineral wealth of Costa Rica, and the
 extraordinary facilities afforded by its position and natural
 advantages. An estimate has been made for establishing a complete
 mining concern in Costa Rica, with houses, iron railroads, stamping
 mills, &c., so as to raise, stamp, and bring into refined gold the
 produce contained in 250,000 tons of ore per year.

 "The result of six years' experience shows that the following list of
 machinery and tools with a few miles of railroad would be sufficient.
 The communication with the mines being satisfactorily established
 by the route of the port of San Juan de Nicaragua and the river
 Serapique, the materials would be sent by the Atlantic at very much
 less cost than by around Cape Horn.

 "It is situated within 14 leagues of the Pacific Ocean and 30
 leagues of the Atlantic, in a mountainous district intersected by
 deep valleys or ravines. The mountains are covered with wood fit for
 fuel, mining, architecture, and machinery. There is a population of
 50,000 inhabitants within one day's journey of the mines. The climate
 is perfectly salubrious, provisions of all kinds remarkably cheap,
 labourers' wages from four to five dollars per month. The mines
 secured are freehold property, and with one exception are unencumbered
 by tribute or native partners. The attention of Government and of
 individuals has recently been directed to the discovery of a road
 from the interior to the river Serapique, which, rising in the high
 lands of Costa Rica, pursues a northerly course and joins the San
 Juan about 10 leagues above the harbour of that name, being itself
 navigable for about 12 leagues above the junction. The opening of
 this road is a matter of much importance to Costa Rica in a general
 point of view; the port of Matina being always bad and impracticable
 during the prevalence of northerly winds; that of San Juan being, on
 the contrary, capacious, easy of access, and at all times perfectly
 secure. The distance is much the same as by the way of Matina. Several
 expeditions have been undertaken with a view of exploring an eligible
 road to the highest navigable point of Serapique, and although as yet
 none fit for mules has been discovered, the results of the experiments
 justify the expectation of success. Individual enterprise is active in
 the attempt, and Government has wisely offered a reward to successful
 speculators.

 "Captain Trevithick and Mr. Gerard, with a particular view to the
 enterprise now under consideration, and after considerable risk and
 labour, succeeded in laying down the navigable head of the Serapique
 and in throwing such light on the intervening tract as will be of
 great assistance to future adventurers. They ultimately constructed a
 canoe in which they sailed down to the port of San Juan."

Plate XIV. shows Trevithick's route across Costa Rica.

A memorandum in Trevithick's writing, apparently a diary, says:--

 "From where we returned our mules to the place where we commenced to
 make our rafts and boat was eleven days' journey, a distance of 50
 or 60 miles. The first and second days after parting with the mules
 we passed some soft ground, with three or four rivulets of water in
 narrow vales, about 10 miles on the side of the decline of the high
 ridge on our left. It could easily be made passable for mules, as
 the bad places where they could not travel did not exceed two or
 three miles; and had we kept a little more to the left above the soft
 ground, probably they could have passed. The next bad place was about
 a mile after the second pass across the San José River, being a very
 deep and abrupt vale. Had we never passed the San José River, but left
 it on our right hand, the road would have been much shorter, and we
 should have avoided this deep vale, and also the three other vales,
 and their three rivers of Montelegre, Juan Mora, and Ajerbi. They
 were, however, small, not more than half the leg in water, which is
 a proof that their source was not above 10 miles off and must have
 originated in the side of the high ridge on our left. None of the
 vales were impassable to mules, except that between the second passing
 of the river San José and the river Montelegre, which was about a
 mile, and might be made passable for mules by a diagonal road to be
 made in the side of the hill a little higher up.

 "Only five or six miles of road would require to be made for mules
 on the whole of the way we came, to where the river Serapique is
 navigable. We observed that we should have avoided those vales by
 passing a few miles more to the left, where we saw one continued high
 ridge running from the highest ridge of the continent, commencing at
 the volcano and terminating in a point near to where the Serapique
 River is navigable.

 "On a regular decline for perhaps 7000 or 8000 feet in height, down
 to near sea-level, which would in that distance have given a fall
 of about half an inch in a yard, four men in ten days would make, I
 have no doubt, this ridge passable for mules on a regular descent to
 where the Serapique River is navigable. I have no doubt if we could
 have spent one week more on our journey we might have passed mules the
 whole distance with us. To carry machinery from where the Serapique
 is navigable to the mines is about one-third farther than from the
 port of Arenas on the south, on which the carriage is two dollars per
 mule load; three dollars might therefore be charged per mule from the
 Atlantic side, a much less cost than by way of Matina, or by going
 around Cape Horn. It would give a speedy communication and a great
 accommodation to the province of Costa Rica, which I doubt not would
 gladly contribute to its making.

 "The mining district occupies the mountain of Aquacate, nearly
 equidistant from the port of Punta de Arenas, in the Gulf of Nicoya,
 and from San José, the capital of the state, about 14 leagues from the
 former and 12 from the latter. The high road passes through the centre
 of the district.

 "The chief outlay after paying for the mines would be for erecting
 stamping mills and making railroads."

This broken information barely gives an idea of the importance of the
Costa Rica mines, or of what Trevithick did between the time of his
landing on the Pacific shore, about 1822, and his leaving the mines on
his search for a new route over the Cordillera to the Atlantic shore,
about 1826 or 1827. Judging from the rough map on which Trevithick has
marked his line of travel across the isthmus, the mines of Machucha,
Quebrada-honda, and Coralillo, were inland from the Gulf of Nicoya,
on the Pacific, some forty or fifty miles, the latter mine having its
water shed into the Rio Grande, while the two other mines, not far
off, opened into the Quebrada-honda River. The central high ridge
of the Cordillera was between the mines and the Atlantic; indeed
the mines are on high ground at the foot of volcanic mountains. San
Mateo seems to have been the place of importance near the mines, and
probably a well-known mule-track was in use through the mountain ridge
to San José, the capital, once numbering thirty thousand inhabitants;
but this line failed to reach a good port on the Atlantic coast. The
travellers, therefore, abandoned the known track, and turning to the
left, made their way between the volcanic peaks of Potos and Barba,
hoping that on the eastern slope of the Cordillera navigable rivers
would be found either to the Atlantic or to the San Juan de Nicaragua,
which joined the Atlantic at the port of San Juan. It was probably at
this volcanic ridge that the precipitous road obliged the mules to be
sent back. The track was then due north, towards Buona Vista, below
which the river Serapique took its rise, running into the river San
Juan. Where they crossed this river was fifty or sixty miles from where
the mules had left them. Trevithick marked the river-crossing with a
steamboat, indicating its navigability; but the writer infers that it
had so much of the mountain torrent about it, that the travellers took
a line still through unexplored country towards the port of San Juan,
on the Atlantic, for the track and the description show that the river
San José was crossed, and also another river running to the Atlantic.
They probably were stopped by swamps on approaching the San Juan, and
retracing their steps to the Serapique, constructed rafts or canoes,
and after hairbreadth escapes sailed down it to the junction with the
San Juan, and down the latter to its junction with the Atlantic at Port
San Juan, or Greytown.

Eleven days were passed from the parting with the mules near the
crossing of the highest ground, from whence they saw a continuous
ridge, commencing at the volcano and terminating near to where the
Serapique is navigable on a regular decline for perhaps seven or eight
thousand feet down to near sea-level, giving a fall for the whole
distance of about half an inch in a yard, or in railway parlance 1 in
70; for this was what was in Trevithick's head, that his steam-horse
should carry where the mule could not, and that miners and machinery
should be so taken to his mines from the Atlantic, giving those who
chose an opportunity of continuing their railway journey to the Pacific.

The writer has heard Trevithick describe the excursion as lasting three
weeks, through woods, swamps, and over rapids; their food, monkeys
and wild fruit; their clothes, at the end of the journey, shreds and
scraps, the larger portion having been torn off in the underwood.

Mr. Thomas Edmonds also listened to Trevithick's narrations, some of
which he gives in the following:--

 "In 1830 I frequently saw Trevithick at the house of Mr. Gittins, at
 Highgate, a schoolmaster, with whom were two boys that had accompanied
 him from Costa Rica, called Montelegre. Before Captain Trevithick
 no European had adventured on or explored the passage along the
 river from the Lake Nicaragua to the sea. In the adventure he was
 accompanied by Mr. J. M. Gerard, a native of Scotland; two boys of
 Spanish origin going to England for their education; a half-caste,
 as servant to Mr. Gerard; and by six working men of the country, of
 whom three went back, after helping to remove obstructions in the
 forest through which the first part of the journey was undertaken.
 The risks to which the party were exposed on their passage were very
 great: they all had a narrow escape from starvation, one of the
 labourers was drowned, and Captain Trevithick was saved from drowning
 by Mr. Gerard. The intended passage was along the banks of the
 river. To avoid the labour of cutting through the forest, the party
 determined to construct a raft, on which they placed themselves, their
 provisions, and utensils; after a passage of no long duration they
 came to a rapid, which almost overturned their raft, and swept away
 the principal part of their provisions and utensils. The raft, being
 unmanageable, was then stopped by a tree lying in the river, with its
 roots attached to the bank; on this tree three of the passengers,
 including Captain Trevithick, landed, and reached the bank; this was
 no sooner done than the current drove the raft away from the tree,
 and carried it, with the remaining passengers, to the opposite bank,
 where they landed in safety, and abandoned the raft as too dangerous
 for further use. The next object was to unite the party again into
 one body. The three left on the other side of the river were called
 upon to swim over: one of the men swam over in safety, the next made
 the attempt and was drowned, the third and last remaining was Captain
 Trevithick, who was either unable to swim or could swim very little.
 In order to improve his chances of safety, he gathered several sticks,
 which he tied in a bundle and placed under his arms; with these he
 plunged into the stream; but the contrivance of the bundle of sticks
 afforded him very doubtful assistance, for the current appeared to
 seize the sticks and whirl him round and round. He, however, finally
 reached within two or three yards of the bank in a state of extreme
 exhaustion. Mr. Gerard going into the water himself and holding
 the branch of a tree, then threw to his assistance the stem of a
 water-plant, holding one of the extremities in his own hand. It was
 not until the fourth time of throwing that Captain Trevithick was
 able to seize the very extremity of the plant (which was leaf) in his
 fingers; on the strength of the leaf his life on the occasion was
 dependent. It was determined to give up any further idea of using a
 raft on the river, and to continue their journey along the banks of
 the river. For subsistence for the remainder of their journey they had
 to depend on the produce of one fowling-piece and a small quantity
 of gunpowder; after a few days the gunpowder got wet by accident,
 and in the attempt to dry it, it was lost by explosion. The party
 finally arrived in a state of great exhaustion at the village, now the
 considerable port of San Juan de Nicaragua, or Greytown; and shortly
 after their arrival a small vessel arrived, which conveyed the party
 to one of the West India islands.

 "Upon one occasion Captain Trevithick was called upon to act in a
 novel capacity, that of a surgeon. An accident happened to a native
 engaged in working an engine erected at a place distant about two
 hundred miles from Lima, by which accident both of his arms were
 crushed. There was no medical man within the distance of two hundred
 miles, and Captain Trevithick, believing that death would ensue if
 amputation was not immediately performed, offered his services,
 which were accepted by the patient. The operation, he informed me,
 was successful; the man rapidly recovered, and showed a pair of
 stumps which could have hardly been distinguished from the result
 of an operation by a regular surgeon. It is not improbable that in
 the warfare in which he had been engaged Captain Trevithick had been
 present and assisted at amputations of limbs of wounded soldiers. He
 thus probably acquired sufficient confidence to undertake and perform
 the operation himself.

 "From Costa Rica Captain Trevithick came to England, with a design,
 among others, of forming a company to work a mine which had been
 granted him (for a term of years) by the Costa Rica Government. Mr.
 Gerard came to England with a similar object in view. Both failed in
 their object. Mr. Gerard was extremely unfortunate with regard to his
 mine, for he spent a considerable fortune of his own in working his
 mine to a loss.

 "The eminence of Captain Trevithick as an engineer is well known. The
 public are indebted to him for the invention of the high-pressure
 steam-engine and the first railway steam-carriage. The latter being
 dependent on the former, Captain Trevithick informed me that the idea
 of the high-pressure engine occurred to him suddenly one day whilst at
 breakfast, and that before dinner-time he had the drawing complete,
 on which the first steam-carriage was constructed. Captain Trevithick
 informed me that in 1830 the original steam railway-engine constructed
 by him in 1808[132] at that time was still running in Wales."

[Footnote 132: Probably referring to the Welsh locomotive of 1804.]

  "SIR,        "STANWIK, CUMBERLAND, _27th November, 1864_.

 "I read in the public prints that in a speech made by you in Belle
 Vue Gardens you referred to the meeting of Robert Stephenson with
 Trevithick at Carthagena, which, if your speech be correctly reported,
 you attribute to accident. The meeting was not an accident, although
 an accident led to it, and that accident nearly cost Mr. Trevithick
 his life; and he was taken to Carthagena by the gentleman that saved
 him, that he might be restored. When Mr. Stephenson saw him he was so
 recovering, and if he looked, as you say, in a sombre and silent mood,
 it was not surprising, after being, as he said, 'half drowned and half
 hanged, and the rest devoured by alligators,' which was too near the
 fact to be pleasant. Mr. Trevithick had been upset at the mouth of
 the river Magdalena by a black man he had in some way offended, and
 who capsized the boat in revenge. An officer in the Venezuelan and
 the Peruvian services was fortunately nigh the banks of the river,
 shooting wild pigs. He heard Mr. Trevithick's cries for help, and
 seeing a large alligator approaching him, shot him in the eye, and
 then, as he had no boat, lassoed Mr. Trevithick, and by his lasso
 drew him ashore much exhausted and all but dead. After doing all he
 could to restore him, he took him on to Carthagena, and thus it was he
 fell in with Mr. Stephenson, who, like most Englishmen, was reserved,
 and took no notice of Mr. Trevithick, until the officer said to him,
 meeting Mr. Stephenson at the door, 'I suppose the old proverb of
 "two of a trade cannot agree" is true, by the way you keep aloof from
 your brother chip. It is not thus your father would have treated that
 worthy man, and it is not creditable to your father's son that he and
 you should be here day after day like two strange cats in a garret; it
 would not sound well at home.' 'Who is it?' said Mr. Stephenson. 'The
 inventor of the locomotive, your father's friend and fellow-worker;
 his name is Trevithick, you may have heard it,' the officer said;
 and then Mr. Stephenson went up to Trevithick. That Mr. Trevithick
 felt the previous neglect was clear. He had sat with Robert on his
 knee many a night while talking to his father, and it was through him
 Robert was made an engineer. My informant states that there was not
 that cordiality between them he would have wished to see at Carthagena.

 "The officer that rescued Mr. Trevithick is now living. I am sure
 he will confirm what I say, if needful. A letter will find him if
 addressed to No. 4, Earl Street, Carlisle, Cumberland.

 "There are more details, but I cannot state them in a letter, and you
 might not wish to hear them if I could.

  "I am, Sir,
  "Your very obedient servant,
  "JAMES FAIRBAIRN,

 "who writes as well as rheumatic gout will let him.

 "P.S.--I forgot to say the name of the officer is Hall.

 "To ---- WATKIN, Esq."

  "DEAR SIR,    "4, EARL STREET, CARLISLE, _16th December, 1864_.

 "On my return from Liverpool this day I find your letter of the 9th.

 "In reply I have the honour to say that if you will be pleased to
 state upon what points you require information, I shall be but too
 happy to furnish it if I can.

 "I have barely time to add that Mr. Fairbairn has left for America,
 which is his home, and has been for many years. He must have been at
 Birkenhead or Liverpool at the date of your letter to me. I was not
 aware that he had written to you. He brought me a paper with your
 remarks about the meeting of Mr. Robert Stephenson and Mr. Trevithick,
 and asked me if it were true that they met at Carthagena as stated,
 as he (Mr. Fairbairn) thought it was at Angostura, and that Mr.
 Trevithick was in danger of being drowned at the Bocasses, _i. e._ the
 mouths of the Orinoco, the Apure, &c, &c. I explained that it was near
 the mouth of the Magdalena.

 "I will just say that it was quite possible Mr. R. Stephenson had
 forgotten Mr. Trevithick, but they must have seen each other many
 times. This was shown by Mr. Trevithick's exclamation, 'Is that
 Bobby?' and after a pause he added, 'I've nursed him many a time.'

 "I know not the cause, but they were not so cordial as I could have
 wished. It might have been their difference of opinion about the
 construction of the proposed engine, or it might have been from
 another cause, which I should not like to refer to at present; indeed,
 there is not time.

 "Pray address me as before. I hold no rank in the British service, and
 in England never assume any.

  "I have the honour to be, dear Sir,
  "Faithfully yours,
  "BRUCE NAPIER HALL.

  "EDWARD W. WATKIN, Esq., M.P., &c.,
  "_Currente Calamo_."

These notes from Mr. Hall and Mr. Fairbairn to Mr. (now Sir Edward)
Watkin[133] arose from the latter repeating what Mr. Robert Stephenson
had related, of his meeting with Trevithick and Gerard at the inn at
Carthagena. Stephenson said, "on his way home from Colombo, and in the
public room at the inn, he was much struck by the appearance and manner
of two tall persons speaking English; the taller of them, wearing a
large-brimmed straw or whitish hat, paced restlessly from end to end
of the room." Gerard and Stephenson entered into conversation, and
Trevithick joined them. Stephenson said that he had a hundred pounds in
his pocket, of which he gave fifty to Trevithick to enable him to reach
England. It seems that had it not been for Mr. Hall's quick eye and
steady hand rescuing Trevithick from the jaws of the blind alligator,
he never would have returned to his native country.

[Footnote 133: Sir Edward Watkin contemplated writing a life of
Trevithick.]

Here was the inventor of the locomotive a beggar in a strange land,
helped by the man whom he had nursed in baby-boyhood, then returning
to England to become a great railway engineer in making known the use
of the locomotive on the level road of the Liverpool and Manchester,
while the real inventor, who looked upon railways and locomotives as
things of a quarter of a century before, was about to recommend them as
the means of passing across the isthmus of Costa Rica from the Atlantic
to the Pacific, over the heights of the Cordillera, by the river San
Juan from Greytown, and by its tributary the Serapique, then by railway
towards the high ground of San José, the capital, and down the western
slope, passing, somewhere not far from the mines, forward to the Gulf
of Nicoya in the Pacific.

The approximate distance would be fifty miles of river navigation,
and eighty or a hundred of railway, with perhaps stiffish but still
manageable inclines, and no avalanches.

A loan by the Costa Rica Government of 1872 states,[134] "for the
completion of the railway from the port of Limon, in the Atlantic
Ocean, to San José de Costa Rica, and on to Heredia and Alajuela," near
to Trevithick's mines, as if to carry out his design of forty-six years
ago to connect the Atlantic and Pacific by railway.

[Footnote 134: See 'The Times,' 7th May, 1872.]




CHAPTER XXIV.

RETURN TO ENGLAND.


In the early part of October, 1827, the writer, then a boy at Bodmin
school, was asked by the master if any particular news had come from
home. Scarcely had the curiosity of the boys subsided, when a tall man
with a broad-brimmed Leghorn hat on his head entered at the door, and
after a quick glance at his whereabouts, marched towards the master's
desk at the other end of the room. When about half-way, and opposite
the writer's class, he stopped, took his hat off, and asked if his son
Francis was there. Mr. Boar, who had watched his approach, rose at the
removal of the hat, and replied in the affirmative. For a moment a
breathless silence reigned in the school, while all eyes were turned
on the gaunt sun-burnt visitor; and the blood, without a defined
reason, caused the writer's heart to beat as though the unknown was his
father, who eleven years before had carried him on his shoulder to the
pier-head steps, and the boat going to the South Sea whaler.

During the next six months father and son sat together daily, the
one drawing new schemes and calculations, the other observing, and
learning, and calculating the weight and size and speed of a poor
swallow he had shot, that the proportions of wings necessary to
carry a man's weight might be known. In these calculations cube
roots of quantities were extracted, which did not accurately agree
with Trevithick's figures, who, asking for explanations, received a
rehearsal, word for word, of the school-book rule for such extractions,
which threw no more light on his understanding than did his own
self-made rule on the writer's comprehension, though both methods
produced nearly the same result.

Within a month of that time he heard of the arrival in England of
Mr. Gerard, his companion in travel, from whom he had separated at
Carthagena.

  "MY DEAR GOOD SIR,   "HAYLE FOUNDRY, _15th November, 1827_.

 "I cannot express the extreme pleasure that the receipt of your
 favour of the 11th inst. from Liverpool gave me, as I had almost
 given up hopes of ever seeing you again, which you will see from the
 letters that I wrote Mr. Lowe; and after the severe rubs that we have
 undergone together, the parting us by shipwreck, as I supposed, at the
 close of our hardships, I doubly felt, and from your long absence, I
 supposed you must have encountered some severe gales; but thank God
 that we are safe landed to meet you and the dear boys again soon. We
 had a very good passage home, six days from Carthagena to Jamaica,
 and thirty-four days from thence for England; and on my return was so
 fortunate as to join all my family in good health, and also welcomed
 home by all the neighbourhood by ringing of bells, and entertained at
 the tables of the county and borough members, and all the first-class
 of gentlemen in the west of Cornwall, with a provision about to be
 made for me for the past services that this county has received from
 my inventions just before I left for Peru, which they acknowledge to
 be a saving in the mines since I left of above 500,000_l._, and that
 the present existence of the deep mines is owing to my inventions.
 I confess that this reception is gratifying, and have no doubt but
 that you will also feel a pleasure in it. I should be extremely happy
 to see you down here; it is but thirty-six hours' ride, and it will
 prepare you for meeting your London friends, as I would take you
 through our mines and introduce you to the first mining characters,
 which will give you new ideas and enable you to make out a prospectus
 that will show the great advantages in Costa Rica mines over every
 other in South America. I think it would not be amiss for you to
 bring with you a few specimens, and after you have seen the Cornish
 mines and miners I doubt not but we shall be able to state facts in
 so clear a light that the first blow well aimed will be more than
 half the battle, and prove a complete knock-down blow, which in my
 opinion ought to be completed previous to your opening your mining
 speculation in general in London. I have made a very complete model of
 the gun, and it is approved of by all who have seen it. Be so good as
 to remember me to the lads and the Manilla man, and write me by return
 of post. I have not as yet made any inquiry about the probability of
 getting adventurers for this new concern. I hope and trust that I
 shall see you in Cornwall previous to our being together in London, as
 it is my opinion that the nature of the concern requires it.

  "I remain, Sir,
  "Your humble servant,
  (Signed) "RICHARD TREVITHICK.

  "MR. JNO. GERARD,
  "_No. 42, St. Mary Axe, London_."

Trevithick's hopeful character enabled him to enjoy life in the
midst of neglect and poverty. During the eleven years of absence in
America his wife and family received no assistance from him. Shortly
after leaving his Quebrada-honda mountains of gold and silver, he was
penniless at Carthagena. On reaching England he possessed nothing but
the clothes he stood in, a gold watch, a drawing compass, a magnetic
compass, and a pair of silver spurs. His passage-money being unpaid, a
chance friend enabled him to leave the ship. In a month from that time
he counted on getting a share of the 500,000_l._ saved in the Cornish
mines by the improvements he had effected in their steam-engines. The
ringing of bells and the talk of the neighbourhood made him forget that
he was a poor man, and the Costa Rica mines were, he believed, soon to
be in full working, though not a single adventurer had been found.

The two lads Montelegre, coming to England to be educated, were sons of
a gentleman of influence and authority in Costa Rica. On their perilous
journey an attack of measles increased their discomforts. Probably one
of those gentlemen has since filled the honourable position in this
country of minister representing the Republic of Costa Rica.

  "MY DEAR SIR,          "LONDON, _November 17th, 1827_.

 "I arrived here from Liverpool last night, and this morning had the
 pleasure of receiving your kind letter of the 15th. The brig 'Bunker's
 Hill,' in which we came from Carthagena to New York, was wrecked
 within a few hours' sail of the port. We were in rather a disagreeable
 situation for some time, but more afraid than hurt. The cargo was
 nearly all lost. The ship was got off, but a complete wreck. The
 cause, however, of my delay in arriving arose from the want of the
 needful. You recollect Mr. Stephenson and Mr. Empson, agents for the
 Colombian Mining Association, whom we met at Carthagena. They kindly
 offered to supply me, but having determined to visit the celebrated
 Falls of Niagara, they insisted on my accompanying them, which I did.

 "I am truly rejoiced to learn that your countrymen retain so lively a
 sense of the importance of your services. I think with you that before
 sounding the public or proceeding further, it might be well we should
 meet quietly to talk over everything and arrange our ideas, and that
 Cornwall, for the reasons you mention and others, would be the better
 place.

 "The boys are well, and desire their respects to you.

  "Your sincere friend,
  "J. M. GERARD.

 "CAPT. TREVITHICK."

Trevithick was friendly with George Stephenson when, in 1805, he nursed
little Bobby. Twenty years afterwards, when George had comprehended
Trevithick's locomotive, and desired his son's return to England to
assist him in making it useful, Robert Stephenson, grown to manhood,
met his father's friend in the wilds of Central America, both of them
having been engaged in mining operations, and both on their return to
England. George Stephenson's son made for himself a fortune and a name,
his friend earned poverty and neglect. These two men, though well known
to the engineering world, had no mutual attraction, and in their native
land remained strangers to each other.

  "MY DEAR SIR,      "42, ST. MARY AXE, _January 13th, 1828_.

 "I had very unexpectedly a letter from Costa Rica this morning by the
 way of Jamaica, including two for you, which I have the pleasure of
 transmitting. Mine is from Montelegre, begun on the 25th of August,
 and finished on the 11th of September, when Don Antonio Pinto, with
 some people from the Alajuela, was to start by the road of Sarapique
 on his way to Jamaica. His intention was to find a better route as far
 as Buona Vista, after which he would probably nearly follow our course
 to the Embarcadero of Gamboa.

 "Whether he succeeded in finding a less rugged road to Buona Vista
 I do not know. That he reached his destination seems clear from
 our letters having come to hand; but from their old date it would
 appear that he had either met with difficulties on the road or with
 considerable detention at San Juan. Montelegre writes me that Don
 Yonge had effected a compromise on your account with the Castros.
 Gamboa got back to San José on the 18th August, twelve days after he
 parted from us, to the great joy of our mutual friends. Mr. Paynter
 had been unwell after our departure. Both he and Montelegre desire
 their kindest recollections to you

  "Yours most sincerely,
  "J. M. GERARD.

 "CAPT. TREVITHICK."

The newly-discovered track taken by the homeward bound over the
Cordilleras soon brought Don Antonio Pinto and others into the field
in search of passable roads to the Atlantic. Twelve days required by
Gamboa to effect his return to San José, a distance of perhaps sixty
miles, indicate the difficulty.

Mr. Gerard passed some weeks with Trevithick in Cornwall arranging the
best means of getting together a company to work on a large scale the
Costa Rica mines.

  "DEAR SIR,        "HAYLE FOUNDRY, _January 24th, 1828_.

 "Yesterday I saw Mr. M. Williams, who informed me that he should
 leave Cornwall for London on next Thursday week, and requested that
 I would accompany him. If you think it absolutely necessary that I
 should be in town at the same time, I would attend to everything that
 would promote the mining interest. When I met the Messrs. Williams
 on the mining concerns some time since, they mentioned the same as
 you now mention of sending some one out with me to inspect the mines,
 and that they would pay me my expenses and also satisfy me for my
 trouble with any sum that I would mention, because such proceedings
 would be satisfactory to all who might be connected in this concern.
 I objected to this proposal on the ground that a great deal of time
 would be lost and that the circumstances of your contracts in San
 José would not admit of such a detention; for that reason alone was
 my objection grounded, and if that objection could have been removed
 I should have been very glad to have the mines inspected by any able
 person chosen for that purpose, because it would not only take off the
 responsibility from us, but also strengthen our reports, as the mining
 prospects there will bear it out, and that far beyond our report. Some
 time since I informed you that I had drawn on the company for 100_l._
 to pay 70_l._ passage-money, and would have left 30_l._ to defray my
 expenses returning to London. The time for payment is up, but I have
 not as yet heard anything about it, therefore I expect there must be
 an omission by the bankers whose hands it was to have passed through
 for tendering it for payment. Perhaps in a day or two I shall hear
 something about it; I would thank you to inform me should you know
 anything about it. The unfavourable result of the gun I attribute in a
 great measure to the change in the Ministry and my not being present
 to explain the practicability of making the machinery about it simple.
 When Lord Cochrane has seen it, and a meeting takes place with him,
 my return to London may again revive its merits. This unfavourable
 report does not lessen its merits, neither will it deter me from again
 moving forward to convince the public of its practicability. I shall
 make immediately a portable model of the iron ship and engine, as they
 will be applicable to packets, which have been attempted at Falmouth,
 but found that the consumption of coals was so great that the whole
 of the ships' burthen would not contain sufficient coals to take them
 to Lisbon and return again, and on that account it was discontinued.
 That insurmountable object will now be totally removed, and I think
 that Lord Cochrane will make a very excellent tool to remove many weak
 objections made by persons not having sufficient ability to judge
 for themselves. His Lordship, being a complete master of science, is
 capable of appreciating their value from theory and from practice. I
 should not be surprised to see him down here to inspect it. It will
 be very agreeable if his Lordship comes here at the same time as
 yourself; he is a remarkably pleasant companion. My hearty thanks for
 your mother's good wishes towards me.

  "Your humble servant,
  "RD. TREVITHICK.

  "MR. JNO. GERARD,
  "_No. 42, St. Mary Axe, London_."

Gerard and Trevithick believed in the great value of the Costa Rica
mines, and in the feasibility of working them profitably could capital
sufficient be obtained. After a year or two passed in fruitless
attempts to form a mining company in England, Mr. Gerard visited
Holland and France with no better success; and while on this mission
died in poverty in Paris, though brought up in youth as the expectant
inheritor of family estates in Scotland. One of his letters says:--

 "Robert Stephenson has given us his experience that it was unwise
 to take many English miners or workers to such countries. The chief
 reliance must after all be placed on the native inhabitants, under
 the direction and training of a small but well-selected party of
 Englishmen.

 "Mining operations in that country are of such recent origin that a
 mining population can scarcely be said to exist. English workmen are
 not so manageable even in this country, and much less so in Spanish
 America, where they are apt to be spoiled by the simplicity and
 excessive indulgence even of the better classes, and where the high
 salaries they receive place them far above the country people of the
 same condition. All this tends to presumption and intolerance on their
 part, and ultimately to disputes and irreconcilable disgusts between
 them and the natives."

Mr. Michael Williams, Mr. Gibson, Mr. Macqueen, and others, were
anxious to take up the mining scheme. The former proposed to send a
person to examine the mines. This was a safe course, but not convenient
to those who had made engagements to return without loss of time with
miners and material to Costa Rica.

Mr. M. Williams informed the writer's brother that at a meeting of
several gentlemen in London, a cheque for 8000_l._ was offered to
Trevithick for his mining grant of the copper mountain in South
America. Words waxed warm, and the proffered money was refused. The
next day Mr. Williams said to him, "Why did you not pocket the cheque
before you quarrelled with them?" Trevithick replied, "I would rather
kick them down stairs!"

In the end Trevithick got nothing for either his South American mines
or those in Costa Rica.




CHAPTER XXV.

 GUN-CARRIAGE--IRON SHIPS--HYDRAULIC CRANE--ICE MAKING--DRAINAGE
 OF HOLLAND--CHAIN-PUMP--OPEN-TOP CYLINDER--HAYLE HARBOUR--PATENT
 RIGHTS--PETITION TO PARLIAMENT.


 "Richard Trevithick, of the parish of Saint Erth, in the county of
 Cornwall, civil engineer, maketh oath and saith that he hath invented
 new methods for centering ordnance on pivots, facilitating the
 discharge of the same, and reducing manual labour in time of action.
 That he is the true inventor thereof, and that the same hath not been
 practised by any other person or persons whomsoever to his knowledge
 or belief.

 "Sworn, 10th November, 1827, before me, Rd. Edmonds."

 "This gun is worked by machinery balanced on pivots giving it
 universal motion, by one man, with the facility of a soldier's musket.
 On one side a man puts in a copper charge of powder; on the opposite
 side a man drops a ball in a bag down the gun, as it stands muzzle
 up. The gunner, who sits on the seat behind the gun, points it and
 pulls the trigger. The firing causes it to run up an inclined plane at
 an angle of 25° for the purpose of breaking the recoil; it runs down
 again with its muzzle at the port, requiring no wadding, swabbing,
 cartridge, or ramming, but runs in, out, primes, cocks, shuts the
 pan, and breaks the recoil of itself; and by three men can be fired
 three times in a minute with accuracy. The gun-carriage is a tube 3
 feet long and 3 feet diameter, made of wrought-iron plate 1/4 of an
 inch thick, centered on a pivot to the deck, with the gunner's seat
 attached, from which he looks through the case. As the gun requires
 no tackle, and but a man on each side to work it, only a space of 5
 feet 6 inches is required from centre to centre of ports, therefore
 a single-deck ship will carry a greater number of guns than are now
 carried on a double-deck ship, be worked with one-third of the hands,
 and be fired five times as fast as at present. A frigate would mount
 fifty 42-pound guns on one deck, with 150 men, and would discharge in
 the same time a greater weight of ball with greater precision than
 five 74-gun ships."[135]

[Footnote 135: Description in Trevithick's handwriting.]

[Illustration: TREVITHICK'S GUN-CARRIAGE AND FRICTION SLIDES,
1827.]

  "HAYLE, CORNWALL, _21st February, 1828_.

 "MY LORD COCHRANE,[136]

 "With great pleasure I read in the papers the announcement of your
 arrival again in England, and am much gratified to find a person of
 your superior natural and practical talents, so rare to be obtained,
 to whom I may communicate my views.

 "I have proposed to Government to build an iron ship, and a gun on
 a new principle, which are to undergo an investigation, and have
 lodged a drawing of the ship and a model of the gun with my friend Mr.
 Gerard, a gentleman who returned with me from America, and who will
 present to you this letter with the above-mentioned drawing and model.

 "I have had an iron boat made for the purpose of sending it to London,
 to show the method of constructing ships on this plan, roomy, strong,
 and cheap. Also a wrought-iron ship with a steam-engine on an improved
 principle, which in a few days will be laid on the stocks at the Hayle
 Foundry iron manufactory."

[Footnote 136: Rough draft, by Trevithick, of unfinished letter.]

Though Lord Cochrane was just the person to be interested in such
schemes, it does not appear that he took any part in them. At that time
he was at work on his own particular ideas for marine propulsion.

  "MY DEAR SIR,           "LONDON, _February, 1828_.

 "Immediately after the receipt of your last, which I only received
 after twelve o'clock on the 7th, I went to the Ordnance Office, where,
 though Colonel Gossett was no longer an official personage, I had
 the good luck to meet him. He told me that the model of the gun was
 at Woolwich, and could not be got at in time to stop the progress of
 the other patent, and which he considered of but little moment, as
 he thought it very unlikely there could be any collision between the
 two inventions. He likewise said that from the official changes that
 had taken place in the office, much loss of time might be incurred by
 recalling the model, which was in train of being examined. To-day I
 have received a letter addressed to you from the Ordnance, by which
 it appears that your model has passed through an unsuccessful ordeal
 before the special committee.

  "'SIR,        "'OFFICE OF ORDNANCE, _21st February, 1828_.

 "'I am directed by the Master General to acquaint you that the Select
 Committee of Artillery Officers, to whom your model of a 42-pounder
 carronade and carriage on a new principle were referred, have reported
 that on examination of the invention, they consider it to be wholly
 inapplicable to practical purposes. Your model is at the Ordnance
 Office, and will be delivered on your sending for it.

  "'I am, Sir,
  "'Your most obedient humble servant,
  "'LOWNDES.

 "'R. TREVITHICK, Esq.'

 "My poor mother, who I regret to say has been very delicate ever since
 your departure, and is now again confined to bed, desires me to say
 that she is very sorry she is not Master General of the Ordnance, to
 give it a fair _practical_ trial, as she thinks Captain Trevithick's
 opinions, though she cannot pronounce his name, may be fairly placed
 in opposition to that of the special committee of artillery officers.

  "Ever faithfully yours,
  "J. M. GERARD."

The recoil gun-carriage was his first occupation after twelve years of
travel in countries where mechanical appliances were less thought of
than weapons of war. He commenced this, his second era of inventions,
with what he called a new thing, though it was but an extension of his
schemes of 1809, when he patented iron vessels, hollow sliding masts
and yards, self-reefing sails, and sliding keels.

The model gun was of brass, resting on a railway formed of two inclined
bars of iron, up which the recoil propelled it into a convenient
position for cleaning and loading. Its own gravity caused it to fall
into the required place for being again fired. The slides also served
as friction-bars to regulate the recoil.

The gun and the slides carrying it were enclosed in a wrought-iron box,
having openings in the front and rear for the passage of the muzzle
and the breech. The muzzle front of the box was pivoted to the deck by
a strong bolt as a centre of motion, whilst its rear was supported on
two small wheels resting on the deck, allowing the gun to change its
line of horizontal fire by sweeping from the centre pivot. The gunner's
seat moved with the carriage, from which he could elevate or depress
the muzzle by a lever. The gun was self-priming and self-cocking;
the powder charge was enclosed in a copper case. Captain Moncrieff's
patent gun-carriage of the present day is described in words somewhat
like those used by Trevithick forty years before. "The recoil lifted
a weight smoothly and without friction; the gun and the weight were
held in the position arrived at by a catch until the gun was loaded and
ready to fire again."[137]

[Footnote 137: See 'The Times,' August 12th, 1870.]

The iron boat mentioned in his note to Lord Cochrane as being made at
Hayle, was "for the purpose of sending to London to show the method of
constructing ships on this plan, roomy, strong, and cheap," and was
thus spoken of in a newspaper of the 26th April, 1829. "The 'Scotsman'
alludes to the intended construction of iron steamboats at Glasgow by
Mr. Neilson:--"For fear of the public being misled on this subject,
we beg to state that so far back as last Christmas twelvemonths we
saw Trevithick, of Cornwall, superintending the construction of an
iron man-of-war launch, with the avowed intention of applying a
similar principle of construction to the building of fast-sailing iron
steamboats." This intimation, in 1829, to the since famous Glasgow
iron-ship builders, that they could not claim the invention because
Trevithick had made such a boat in 1827, was probably in ignorance of
Trevithick's patent and models of 1809,[138] explaining the advantages
of ships of iron, either under sail or under steam, for commerce or
for fighting-ships. The improved high-pressure steam-engine then in
hand for iron ships was but the perfecting of his plans of twenty years
before.[139]

[Footnote 138: See vol. i., p. 302.]

[Footnote 139: See vol. i., p. 329.]

  "LAUDERDALE HOUSE, HIGHGATE, _April 19th, 1830_.

  "MR. GILBERT,

 "Sir,--I find by looking into the 'Art of Gunnery' that a 42-lb. shot
 discharged at the rate of 2000 feet a second in vacuum would send it
 to the height of 63,360 feet, which multiplied by the weight of the
 shot would be 2,661,120 lbs., with 12 lbs. of powder; and as guns,
 after being heated to about the heat of boiling water, will recoil
 their usual distance with half their first charge of powder, it proves
 that one-half the powder at first is lost in heating the gun to about
 212°, which is a great deal under the heat of fired powder, therefore
 only 6 lbs. of powder effective force is applied to the ball. Now
 suppose this 6 lbs. of powder to be one quarter part carbon, 1-1/2 lb.
 is all the heat that can possibly be applied to perform this duty;
 then 1 lb. of carbon would be equal to 1,774,080 lbs. of duty actually
 performed; but if you take into calculation the great loss of power
 by the powder not being instantly all set on fire, with the gun so
 much below the heat of fired powder, the windage by the sides of the
 shot, the ball flying from the powder, and the immense power remaining
 in the gun at the time of the ball leaving its muzzle; if this was
 applied expansively, as in a cylinder, it may fairly be said to have
 double this power, or 3,548,160 lbs. for 1 lb. of carbon consumed,
 which, multiplied by 84, being the pounds in 1 bushel of carbon,
 gives 300 millions of duty. If it was applied to the best advantage,
 say on a piston, calling powder one thousand atmospheres, it would far
 exceed that duty. A gun 9 feet long and 7-inch bore has 16 feet of
 cold sides, and condenses at first one-half of its force by its cold
 sides and loses 150 millions in a 200th part of a second, while the
 ball passes from the breech to the muzzle. This gives 221,760 lbs.
 condensed by each foot of surface sides in so short a time. Binner
 Downs cylinder was taken as condensing 2500 lbs. for each surface
 foot in six seconds; therefore, without taking into account the great
 difference in time, there is eighty-eight times as much power lost
 by each foot of cold sides of the gun as by the cylinder sides. This
 shows what a considerable power is lost by cold sides where the vapour
 is so rare. Boulton and Watt's engine, doing twenty millions, performs
 with 1 lb. of coal a duty of 240,000 lbs., or about 1/14th part of
 what is done by 1 lb. of carbon in powder. The water evaporated by the
 boiler is 7 lbs. thrown into steam by 1 lb. of coal, and a duty of
 33,750 lbs. for each pound of water evaporated.

 "Suppose 1 lb. of powder to contain 12 oz. of nitre and 4 oz. of
 carbon, and 1/24th part of the nitre to be a fixed water, which would
 be half an ounce of water in every pound of powder, making the carbon
 eight times as much as the water; from this data 1 lb. of water in
 powder would perform a duty of 28,385,280 lbs.

                                           lbs.
  1 lb. of carbon in powder             3,548,160 } 14 times the consumption
  1 lb. of coal in Boulton and Watt's             }
      engine                              240,000 } by the engine.

  1 foot of cold sides of the gun         221,760 { 88 times as much loss
  1  "         "       of the cylinder     33,750 { by the cold sides of
                                                  { the gun

  1 lb. of coal for 7 lbs. of water in            { 14 times as much coal
      steam                                       { for water into steam
  1 lb. of carbon for 8 oz. of water in powder    { as for water in
      powder                                      { powder.

 "By this it appears that heat is loaded with fourteen times as much
 water in steam-engines as in powder, and does only 1/14th part of the
 duty of the water in powder. It is possible to heat steam independent
 of water, because if we work with steam of ten atmospheres, it would
 have ten times the capacity for heat, being in proportion to its
 gravity. The boiler standing on its end, with the fire in the bottom,
 and the water 1 foot thick above it, with a great number of small
 tubes from bottom to top, having great surface sides to heat the steam
 above the water, by working with a low chimney and slow fire, the
 tubes in the steam part of the boiler would not exceed 600° or 700° of
 heat, which would not injure them; as less water would be generated
 into steam, a very small part of the boiler would be sufficient for
 it; and as the coal required would be less, the boiler required would
 be very small. I state the foregoing to remind you that but little is
 yet known of what heat may be capable of performing; as this data so
 far exceeds whatever has been calculated on the power of heat before,
 when compared with steam in an engine.

 "The power is sure, if we can find how to conduct it.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK.

 "If you can spare time please to write to me."

The foregoing may be classed either under cannon or steam-engine;
TREVITHICK combined them under the general laws of expansion
by heat. Three years had passed since the committee of artillery
officers sitting on his gun had given a verdict of no go; yet the
subject was not forgotten, and his calculations enabled him to discover
the explosive force, and the speed of the projectile in different parts
of the gun, things which are now ascertained by mechanical tests and
measures.

If a 7-inch cannon 9 feet long loses by absorption of heat during
the time of the passage of the shot to the muzzle one-half of the
expansive force of the powder, it is time to wrap our guns as well
as our steam-engines in non-conductors. The greater heat of exploded
powder than of steam caused eighty-eight times the amount of loss from
abstracted heat, and yet the force from a pound of carbon in powder,
was fourteen times as much as the Watt engine gave from a pound of coal.

  "MR. GIDDY,   "LONDON, NO. 42, ST. MARY AXE, _June 18th, 1828_.

 "Sir,--A few days since a Mr. Linthorn called on me and requested me
 to accompany him to Cable Street, near the Brunswick Theatre, to see
 a crane worked by the atmosphere, in a double-acting engine attached
 to it. He has a patent, and has entered into a contract with the St.
 Katharine's Dock Company to work their cranes, 140 in number, by a
 steam-engine of sufficient power to command the whole of them, by
 placing air-pipes around the docks, with a branch to each crane. To
 each crane is fixed a 10-inch cylinder, 20-inch stroke, double-acting.
 The atmosphere pressing on the piston like steam, the air is drawn
 from the pipes by a large air-pump and steam-engine.

 "On being requested to give my opinion on this plan, after seeing
 one crane worked, I informed them of the disappointment that the
 ironmaster, Mr. Wilkinson, in Shropshire, several years since
 experienced, on the resistance of air in passing through long pipes
 from his blast-engine to his furnaces. He said he was aware of that
 circumstance, and it had since been further proved in London by one of
 the gas companies attempting to force gas a considerable distance, and
 who also failed.

 "He thought that forcing an elastic fluid, and drawing it by a vacuum,
 were very different things, and that the error was removed by drawing
 in place of forcing. For my part I am not convinced on this head; but
 am still of opinion that the result on trial will be found nearly the
 same. However, let that be as it may, the expense and complication of
 the machine, having a double engine, with its gear attached to every
 separate crane, together with the immense quantity of air thrown into
 the air-pump from 140 double engines of 10 inches diameter, 20-inch
 stroke, eighty strokes per minute, and considering the numerous air
 leaks in such an extent of pipes and machines, must reduce the effect
 of the pressure of the atmosphere on each piston to a comparatively
 small power, unless the air-pump and steam-engine are beyond all
 reasonable bounds.

 "Those objections I made them acquainted with, and said that, before
 they went to such an expense, it would be a safer plan to first make
 further inquiry, so that their first experiment might be on a sure
 plan, for the other dock companies were looking for the results of
 this experiment.

 "At the time I was informed of this plan, a thought struck me that
 it might be accomplished by another mode preferable to this: by a
 steam-engine to force water in pipes round the dock, to say 30 or 40
 lbs. to the inch, more or less, and to have a worm-shaft, working in
 a worm-wheel, the same as a common roasting-jack, and apply to the
 worm-shaft a spouting arm like Barker's mill; the worm-shaft standing
 perpendicular would work the worm-wheel fixed in the chain-barrel
 shaft of the crane.

 "This would make a very simple and cheap machine, and produce a
 circular motion at once, instead of a piston alternating motion to
 drive a rotary motion. My report had some weight with them; inquiry
 is to be made into the plan proposed by me, so as to remunerate
 me, provided my plan is considered good. Mr. Linthorn wishes an
 investigation before scientific and able judges, and requested me to
 name some one. I must again make free in asking the favour of your
 advice (which you have so ably given me for thirty years) on this
 plan. Mr. Linthorn intends to request Dr. Wollaston to accompany you,
 any day convenient to you. In the meantime, should you see him, it
 might not be amiss to mention it to him; and should you be able to
 attend for an hour or two to this business, I would thank you to drop
 me a note, saying when it may be convenient. There is a memorandum of
 an agreement between Mr. Linthorn and me; but the plan I suggest is
 only at present made public to him and yourself.

  "Your most obedient servant,
  "RICHARD TREVITHICK."

The reduction of friction by the use of an air-vacuum engine for
working cranes, as designed by Mr. Linthorn, in lieu of an air-pressure
engine, was doubted by Trevithick.

The Mont Cenis pneumatic-pressure machines which the writer saw at work
lost much power by friction before experience had taught remedies.
The pneumatic vacuum tubes which propelled the trains on the South
Devon Railway, failed to give the power that was expected. Sir William
Armstrong's hydraulic cranes, brought into use not many years after the
date of Trevithick's letter, have been found effective. The writer, not
knowing that Trevithick had before recommended hydraulic cranes for
warehouses, accompanied Sir William over his works, then being erected
near Newcastle-on-Tyne, and talked with him on the detail of his crane
designs.

Trevithick thought of giving circular motion to the crane chain-barrel
by the attachment of a screw-propeller, acted on by the force of a
current of water at a pressure of 30 or 40 lbs. to the inch. Sir
William Armstrong's arrangement was quite different; the merit due to
Trevithick was for having pointed out the suitability of water as a
means of conveying power through warehouses where fire was inadmissible.

  "MR. GILBERT,   "LONDON, 42, ST. MARY AXE, _June 29th, 1828_.

 "Sir,--Fancy and whim still prompt me to trouble you, and perhaps
 may continue to do until I exhaust your patience. A few days since
 I was in company where a person said that 100,000_l._ a year was
 paid for ice, the greatest part of which was brought by ships
 sent on purpose to the Greenland seas. A thought struck me at the
 moment that artificial cold might be made very cheap by the power
 of steam-engines; by compressing air in a condenser surrounded by
 water, and an injection to the same, so as to instantly cool down
 the highly-compressed air to the temperature of the surrounding air,
 and then admitting it to escape into liquid. This would reduce the
 temperature to any state of cold required.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK."

Trevithick's ideas for making ice have since been patented and made
useful, though the detail of the operation has been improved by
experience.

The Dutch, extending the use of steam on the Rhine and also in
sea-going ships, wished Trevithick to see what was going on in
Holland, where his nephew, Mr. Nicholas Harvey, was actively engaged
in engineering. He had not money enough for the journey, and borrowed
2_l._ from a neighbour and relative, Mr. John Tyack. During his walk
home a begging man said to him, "Please your honour, my pig is dead;
help a poor man." Trevithick gave him 5_s._ out of the 40_s._ he had
just begged for himself. How he managed to reach Holland his family
never knew; but on his return he related the honour done him by the
King at sundry interviews, and the kindness of men of influence in
friendly communion and feasting.

  "MR. GILBERT,            "LONDON, _July 31st, 1828_.

 "Sir,--The night before last I arrived from Holland, where I spent ten
 days. I found my relative there, Mr. Nicholas Harvey, the son of John
 and Nancy Harvey. He is the engineer to the Steam Navigation Company
 at Rotterdam. They have a ship 235 feet long, 1500 tons burthen,
 with three 50-inch cylinders double, also two other vessels 150 feet
 long, each with two 50-inch cylinders double, ready to take troops to
 Batavia. The large ship with three engines cost 80,000_l._ The Steam
 Navigation Company built them, and many others of different sizes.
 This company has been anxious to get me to Holland, having heard of
 the duty performed by the Cornish engines. They were anxious to know
 what might be done towards draining and relieving Holland from its
 ruinous state.

 "Immediately on arrival I joined the Dutch company, and entered into
 bonds with them.

 "I give you, as near as I can, the present state of the country. About
 250 years since, a strong wind threw a bank of sand across the mouth
 of the river Rhine, which made it overflow its banks; 80,000 lives
 were lost, and about 40,000 acres of land, which remain to this time
 under 12 feet of water.

 "About 100 years since the head and surface of the river Rhine was
 5 feet below what it now is. The under floors of houses in Holland
 are nearly useless, and in another century must be totally lost,
 unless something is done to prevent it. The river at present is
 nearly overflowing its banks. In consequence of the rise of water,
 the windmill engines cannot lift it out. To erect steam-engines,
 they never could believe would repay the expense. Nearly one-half
 of Holland is at present under water, either totally or partially,
 because the ground kept dry in winter is flooded in summer.

 "About six years since it was in contemplation to recover the 40,000
 acres before mentioned, and a company was formed of the King and the
 principal men in Holland, to drain this by windmills, which they
 estimated would cost 250,000_l._, and making the banks and canals
 450,000_l._ more, when made by men's labour, and seven years to
 accomplish it.

 "This seven years was a great objection, because of the unhealthy
 state of the country while draining. The water is about 18 inches
 every year, to be lifted on an average 10 feet high. I have been
 furnished with correct calculations and drawings from this company.

 "They expected to have drained 40,000 acres in seven years, at a cost
 of 700,000_l._, which, when drained, would have sold at 50_l._ per
 acre, about two millions.

 "I find, from the statement given me, of 18 inches of water to be
 lifted 10 feet high, it would require about one bushel of coal to lift
 the water from one acre of ground for one year, and that a 63-inch
 cylinder double would perform the work of 40,000 acres, when working
 with high steam and condensing, at an expense of less than 3000_l._
 per year. Engines in boats would cut and make the embankments and
 canals, without the help of men. I proposed six cylinders of 60 inches
 diameter, double power, which would drain the water in one year;
 and also four others for cutting the canals and making embankments.
 The expense would not exceed 100,000_l._ and one year, instead of
 700,000_l._ and seven years. Above 60,000 acres more are to be drained.

 "It was also proposed by Government to cut open the river Rhine to
 1000 yards wide and 6 feet deep for 50 or 60 miles in length; they
 supposed it would cost them ten millions sterling. I proposed to make
 iron ships of 1000 tons burthen, with an engine in each, which would
 load them, propel, and also empty them for about 1_d._ per ton. Each
 ton will be about a square yard, and the cutting the river Rhine 1000
 yards wide, 6 feet deep, 50 or 60 miles in length, will not cost one
 and a half million, and be accomplished in a short time. I further
 proposed that all this rubbish be carried into the sea of the Zuyder
 Zee, which would make dry, by embanking with the rubbish, nearly
 1,000,000 acres of good land, capable of paying ten times the sum of
 cutting open the river Rhine.

 "All this would add 100 per cent. more to the surface of Holland, and
 at this time it is much wanted, because their settlements abroad are
 free almost of the mother-country, and they have too many inhabitants
 for the land at present. I made them plans for carrying the whole into
 effect, and have closed my agreement with them.

 "In a few days I shall go to Cornwall, and promised to return again
 to Holland within a month. I saw Mr. Hall and the engineer of the
 Dock Company to-day. They are satisfied that the plan for working the
 cranes is a good one. I am to see them again on Monday next; after
 which I shall return home, where I hope to see you, to consult you on
 the best plan for constructing the machines for lifting the water,
 cutting the canals, and making the dykes.

  "I remain, Sir,
  "Your very obedient servant,
  "RICHARD TREVITHICK."

In this mere outline of a life it is impossible to go fully into the
merit of Trevithick's plans for doubling the land surface of Holland.
A drainage company was formed in London with a board of directors,
some of whom thought that a new kind of engine should be invented and
patented as a means of excluding others from carrying on similar but
competing operations. Trevithick, always ready to invent new things,
though never forgetting his experience with old things, instinctively
returned to the Dolcoath engines, and recommended them as suitable
for the pumping work; but finally a new design was determined on, and
Harvey and Co., of Hayle, received orders for the construction, with
the greatest possible dispatch, of a pumping engine for Holland.

This happening shortly after the writer had been taken from the Bodmin
school, he was desired to help in the erection of this engine, and
after working-hours made a drawing of its original form.

Plate XV. _a_, iron barge; _b_, wood frame supporting pump; _c_,
open-top steam-cylinder 3 feet diameter, 8-feet stroke; _d_, piston
guide-wheel; _e_, connecting rod; _f_, fly-wheel; _g_, cranked axle
working air-pump bucket; _h_, connecting rod for air-pump bucket;
_i_, air-pump; _j_, condenser; _k_, steam and exhaust nozzles; _l_,
eccentrics working steam and exhaust valves; _m_, steam-pipe; _n_,
cylindrical boiler, with internal fire-tube; _o_, external brick flues;
_p_, chimney; _q_, feed-pump; _r_, feed-pipe; _s_, cup or rag-wheel;
_t_, rag-chain, with iron balls; _u_, pump-barrel, 3 feet diameter;
_v_, wheel guiding balls into bottom of pump-barrel; _w_, launder.

[Illustration: PLATE 15

TREVITHICK'S CHAIN AND BALL PUMP.

  London: E. & F. N. Spon, 48, Charing Cross        Kell Bro^s. Lith London
]

After a few successful though noisy trials, an alteration was made in
the endless chain and in the guide-roller near the pump bottom. An
amount of slack in the chain caused the balls to knock on passing this
roller before entering the pump bottom. A chain having long links or
bars of iron of uniform length, from ball to ball, jointed together
by cross-pins, was substituted for the short link chain, and passed
over a revolving hollow square frame at the bottom of the pump, in
place of the curved roller-guide in the drawing. Each of the four sides
of this square hollow frame was of the same length as the jointed link,
and the balls lay in the hollow of the frame without touching it,
contact being only on the links. The balls were thus guided directly
into the bottom of the pump on their upward course with a rigid chain,
and the swing and knocking was avoided. This pump was in principle the
traditional rag-and-chain pump of a hundred years before; yet no trace
of its use is met with during Trevithick's life in Cornwall. The early
pump had rag balls, in keeping with the mechanical ignorance of the
time, and suitable to man's power.

Trevithick's pump with iron balls raised "7200 gallons of water 10 feet
high in a minute with 1-1/2 lb. of coal,"[140] retaining all the original
simplicity of the earlier rag-pump, having uniform circular motion and
constant stream, without the use of a single valve. The engine and pump
are thus described by him:--

[Footnote 140: See letter, vol. ii., p. 332.]

 "The first engine that will be finished here for Holland will be a
 36-inch cylinder and a 36-inch water-pump, to lift water about 8 feet
 high. On the crank-shaft there is a rag-head of 8 feet diameter, going
 8 feet per second, with balls of 3 feet diameter passing through the
 water-pump, which will lift about 100 tons of water per minute. It is
 in an iron boat, 14 feet wide, 25 feet long, 6 feet high, so as to be
 portable and pass from one spot to another without loss of time. This
 will drain 18 inches deep of water (the annual produce on the surface
 of each acre of land) in about twenty minutes; to drain each acre with
 about a bushel of coal costing 6_d._ per year. The engine is high
 pressure and condensing."[141]

[Footnote 141: See Trevithick's letter, vol. ii., p. 315.]

It was something like the Newcomen open-topped cylinder of a
hundred years before, but with a heavy piston, on the top of which
a guide-wheel equal in diameter to the cylinder turned on a pin, to
which the main connecting rod was jointed. The guide-wheel prevented
any tendency to twist the piston from the angular positions of the
connecting rod, and allowed the crank-shaft to be brought comparatively
near to the cylinder top. The boiler was cylindrical, of wrought iron,
with internal fire-tube and external brick flues; and gave steam of
about 40 lbs. on the inch above the atmosphere, which, acting under the
piston, caused the up-stroke, an expansive valve reducing the average
pressure in the cylinder by one-half. The down-stroke was made by the
atmospheric pressure of 14 lbs. on the inch, on the piston, its lower
side being in vacuum, together with the weight of the thick piston and
connecting rod, and the momentum of the revolving parts.

My readers must not suppose that this was an attempt to revive the
discarded Newcomen engine; the likeness was only apparent; its power
was mainly from the use of strong expansive steam, giving motion
in the up-stroke through a rigid connecting rod, with controlling
and equalizing crank and fly-wheel. It was not, as the Newcomen,[142]
dependent for its power on the atmospheric pressure; and having no
cylinder cover, or parallel motion, or beam, was not a Watt engine,
though it had the Watt air-pump and condenser.

[Footnote 142: See vol. i., p. 5.]

The Dolcoath engines continued to work with open-topped cylinders a
quarter of a century after the Watt patent; and when they had passed
away, many of Trevithick's high-pressure steam-engines retained the
same form of outline, but had neither cylinder covers, parallel
motion, air-pump, nor vacuum. The agricultural engines of 1813[143] and
the South American engines of 1816[144] had neither cylinder cover nor
any other part of the Watt engine, yet they successfully competed with
it in power, economy, and usefulness.

[Footnote 143: See vol. ii., p. 37.]

[Footnote 144: See vol. ii., p. 208.]

This design reveals a stumbling-block that superficial people fall
over. The boiler in the boat was surrounded by brick flues, while a
life-long claim of Trevithick's is that before his tubular boiler with
internal fire, there could not be a successful steamboat, because brick
flues were dangerous in sea-going vessels, but in an iron boat in
smooth water it answered its purpose without in any respect falsifying
Trevithick's former claims or plans.

The chain pumping machine was in an iron barge, the 36-inch diameter
pump fixed just outside the bow, its lower end a foot in the water;
its height of 8 or 9 feet enabled the water from the pump-head to
flow through launders over the banks of the lakes to be drained. Some
of the directors came to Hayle to see it work, and were well pleased
at the constant stream of water rushing from the foaming pump-head
into the launders. The large size of the rag-wheel gave the rapidly
revolving chain and balls a great speed. In passing through the pump
each ball forced upwards the water above it, and drew up after it the
following water; before any ball had passed out at the top of the pump
the following ball had entered its bottom. The directors having desired
the writer to take the engine to Holland and set it to work with the
least possible delay, adjourned for refreshment before starting for
London. In those few minutes differences arose, resulting in the engine
remaining for months in the barge, and then going to the scrap heap.

Years afterwards others acted on Trevithick's drainage ideas, and
Harvey and Co. built Cornish pumping engines with steam-cylinders 112
inches in diameter, similar in principle to the Dolcoath engine[145] of
1816, which effectually drained the Haarlem lake.

[Footnote 145: See vol. ii., p. 168.]

The Rhine during 100 years, in its passage through the low flat lands,
had by deposit raised the level of its waters 5 feet, threatening to
overflow the embankments and drown the surrounding country, that to a
large extent was at a lower level than the river. All drainage from
such land had to be pumped over the river bank, in many places 10 feet
above the cultivated surface. Windmills had been used as pumping power,
and a company had contemplated laying out 700,000_l._ in windmills and
canals for drainage.

If the surface water averaged 18 inches in depth yearly, Trevithick
could by steam-engines drain an acre of land by the consumption of
a bushel of coal yearly. Four engines with cylinder of 63 inches in
diameter would drain 160,000 acres, and four smaller engines in barges
with suitable apparatus were to cut canals and construct embankments.
The deposit of a hundred years was also to be removed, and the Rhine
deepened 6 feet for a breadth of 1000 yards, and a length of 50 or 60
miles, by steam-dredgers, as used twenty years before in deepening
the Thames,[146] to be fixed in iron ships of a thousand tons burthen.
The cost of dredging from the bed of the river into a barge would be
1_d._ per ton; but this would be more than repaid by making with it an
embankment, enclosing the Zuyder Zee, which would then in its turn be
drained and made pasture land.

[Footnote 146: See vol. i., p. 243.]

Before leaving for America he had reported on the best means of
improving St. Ives Bay.[147] Hayle Harbour was a branch of it, and
he now suggested to Mr. Henry Harvey methods for deepening and
improving it. A rival company of merchants and engineers, known then
as Sandys, Carne, and Vivian, after many fights had recourse to law
on the question of the course of a stream which had been changed by
alterations during the making of wharfs and channels for ships.

[Footnote 147: See vol. i., p. 343.]

Trevithick made a model in wood, movable layers of which indicated
changes of level caused by workmen at different periods, giving a
different course to the river bed. Mr. Harvey's counsel, since known
as Lord Abinger and Sir William Follett, complimented Trevithick on
the facility of understanding the case by reference to the model. The
writer having carried the surveying chain, was present at the trial at
the Bodmin assizes in 1829.

  "MR. GILBERT,      "HAYLE FOUNDRY, _September 14th, 1829._

 "Sir,--I expected to have seen you before this, but am detained by Mr.
 Harvey's attorney to settle the Foundry Quay. As I made the drawing
 and model of the disputed ground, and was examined in evidence in
 court, it was thought proper that I should be present at the time
 that Mr. Peters came to determine the boundary line between the two
 companies. This cannot be concluded for ten days.

 "As I have been so long detained I wish to await your arrival in
 Cornwall for the purpose of trying the new engine while you are down,
 and will thank you to inform me when you intend to be with us.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK."

Erskine, who had expressed the opinion favourable to Trevithick's
engine more than twenty years before,[148] was in this trial the counsel
for the opposing side. The verdict was in favour of Mr. Harvey, or
Trevithick's side.

[Footnote 148: See vol. ii., p. 129.]

A former chapter[149] speaks of promises to pay certain savings by the
use of Trevithick's inventions prior to his leaving for America. The
United Mines refused to continue the payment, and on Mrs. Trevithick's
application to Mr. Davies Gilbert for advice he kindly wrote to the
Williamses, who managed those mines, and received the following reply:--

[Footnote 149: See vol. ii., p. 108.]

  "DEAR SIR,        "SCORRIER HOUSE, _November 14th, 1820_.

 "... with regard to Mrs. Trevithick's claims for savings on engines at
 the United Mines, there is much to be said.

 "Before Mr. Trevithick went abroad he sold half the patent right
 to William Sims, our engineer, who very strongly recommended that
 two of the engines at the United Mines should be altered to what he
 considered his patent principle, but the alterations proved very
 inferior to his expectations, and to this circumstance I attribute
 much of the objections in question. Mr. Henry Harvey has perhaps
 told you who the partners are in the patent, and when you next come
 into this county I shall be much pleased to wait on you at Tredrea
 that you may hear the whole of the case; and though the United Mines
 adventurers are far from being a united body, I am very sure my sons,
 who are their managers, are desirous to recommend what appears to them
 right, and they will with myself be obliged for your opinion after you
 have heard the whole matter on both sides.

  "Dear Sir,
  "Yours very sincerely,
  "JNO. WILLIAMS.

 "DAVIES GILBERT, Esq., M.P."

The opinion of Mr. Williams' elder son, Michael, has been given.[150]
Some of the family were quakers. No further money payment for the
saving of fuel followed this carefully civil note, until Trevithick,
on his return from America, called at Scorrier House in a very
threatening attitude on 31st October, 1827, when Mr. Williams, sen.,
said his reason for not continuing the payment was from his belief that
the term of the patent had expired. Then came the following lawyer's
letter:--

[Footnote 150: See letter from Mr. Michael Williams, vol. ii., p. 109.]

  "SIR,              "PENZANCE, _7th November, 1827_.

 "I was at Captain Trevithick's yesterday, who observed to me he saw
 you at Scorrier a few days ago, and requested you would be good enough
 to settle the arrears on the savings on some of the engines in the
 mines for which you acted, none having been paid for a year or two,
 when you stated that the payment had been discontinued on account of
 the patent having expired. I find on a reference to the patent that it
 will not expire till May, 1830.

  "I am, Sir,
  "Your obedient servant,
  "RD. EDMONDS.

 "JOHN WILLIAMS, Esq., _Scorrier_."

  "SIR,               "HAYLE, _January 24th, 1828_.

 "Yesterday I called on Mr. Williams, and after a long dispute
 brought the old man to agree to pay me 150_l._ on giving him an
 indemnification in full from all demands on Treskerby and Wheal
 Chance Mines in future. He requested that you should make out this
 indemnification. I could not possibly get them to pay more, and
 thought it most prudent to accept their offer rather than risk a
 lawsuit with them.

  "I remain, Sir,
  "Your obedient servant,
  "RICHARD TREVITHICK.

 "RD. EDMONDS, Esq.

 "Treskerby and Wheal Chance were, I believe, the only mines that
 paid for the use of the pole patent. Mr. John Williams, sen., of
 Scorrier, was purser of those mines. The agreement was that patentees
 should have one-fourth part of the savings of coal above twenty-six
 millions. The one-half of this fourth part from these two mines for
 some years was about 150_l._ per annum. This did not relate to the
 boilers; Trevithick unfortunately did not take out a patent for
 that improvement. The adventurers of two or three mines only had the
 honesty to pay 100_l._ for each mine; others made use of it without
 acknowledgment.

  "RD. EDMONDS.

 "PENZANCE, _12th January, 1853_."

Such were the recollections of the family solicitor many years after
the events had passed. The cylindrical high-pressure steam boiler and
engine was really included in the patent of 1802; but frequent detail
changes, consequent on size and position and local requirements, were
made up to 1811, when a perfected form was arrived at, which is still
in use. In principle it was unaltered and not materially different in
form, but being used for larger engines, looked different. The inventor
saw nothing in this difference, but the public did, and in the absence
of the only man who could prove their error refused to pay on the plea
of its not being patented. On his return from America he demanded
1000_l._ from each of the large Cornish mines, as a settlement in full
for all benefits derived from the use of the Trevithick high-pressure
steam-boiler. He had proved the weakness of the law years before, when
three eminent counsel had given opinions on the 1802 patent, one of
them believing the patent good, because the principle contained was
new; two of them feared that similarity of details might invalidate
it:[151] so he determined to apply to the Government for remuneration for
benefits that might be called national.

[Footnote 151: See vol. ii, p. 129.]

  "MR. RD. EDMONDS,        "HAYLE, _December 20th, 1827_.

 "Sir,--I send the principal heads of what you will have to put in
 form to lay before the House. It is very defective; but you will
 be assisted by Captain Andrew Vivian, who can give dates and
 particulars, having been engaged with Mr. Gilbert and Captain Matthew
 Moyle in making out the duty performed at that time by Boulton and
 Watt and Hornblower's engines. He can also give you the results of the
 late improvements, with much more information than I can give. I saw
 him yesterday for this purpose; he will assist you with all his power,
 and will call on you at Penzance on Friday or Saturday. As I shall
 with pleasure pay him for his trouble, you need not fear calling on
 him for what assistance you need.

 "Mr. Gerard and I propose to leave this for London on Saturday. If you
 think it necessary to see me, let Captain Vivian know it, and all meet
 at my house. I have sent you one of the monthly reports, in which you
 will see John Lean's report of Dolcoath engines, from which I have
 given you in my statement the average results and savings.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK.

 "P.S.--I was at Dolcoath account on Monday, and made known to them
 my intention of applying to Government, and not to individuals, for
 remuneration. They are ready to put their signatures to the petition,
 and so will all the county. I fear that it is as much as we shall do
 to get it before the House in time."

The following petition was drawn up and put into the hands of his old
friend Davies Gilbert, then a Member of Parliament:--

 "TO THE HONOURABLE THE COMMONS OF THE KINGDOM OF GREAT BRITAIN AND
 IRELAND IN PARLIAMENT ASSEMBLED.

 "The Humble Petition of Richard Trevithick, of the Parish of Saint
 Erth, in the County of Cornwall, Civil Engineer, 27th February, 1828,

 "SHEWETH:

 "That this kingdom is indebted to your petitioner for some of the
 most important improvements that have been made in the steam-engine,
 for which your petitioner has not hitherto been remunerated, and for
 which he has no prospect of being ever remunerated except through the
 assistance of your Honourable House.

 "That the duty performed by Messrs. Boulton and Watt's improved
 steam-engines in 1798, as appears by a statement made by Davies
 Gilbert, Esq., and other gentlemen associated for that purpose,
 averaged only fourteen millions and half (pounds of water lifted 1
 foot high by 1 bushel of coals), although a chosen engine of theirs,
 under the most favourable circumstances, at Herland Mine lifted
 twenty-seven millions,[152] which was the greatest duty ever performed
 till your petitioner's improvements were adopted, since which the
 greatest duty has been sixty-seven millions, being more than double
 the former duty. That prior to the invention of your petitioner's
 boiler the most striking defect observable in every steam-engine was
 in the form of the boiler, which in shape resembled a tilted waggon,
 the fire applied under it, and the whole surrounded with mason-work.
 That such shaped boilers were incapable of supporting steam of a high
 pressure, and did not admit so much of the water to the action of the
 fire as your petitioner's boiler does, and were also in other respects
 attended with many disadvantages.

 [Footnote 152: See Mr. Taylor's report on Herland engine, vol. ii. p.
 118.]

 "That your petitioner, who had been for many years employed in making
 steam-engines on the principle of Boulton and Watt, and had made
 considerable improvements in their machinery, directed his attention
 principally to the invention of a boiler which should be free from
 these disadvantages; and after having devoted much of his time and
 spent nearly all his property in the attainment of this object, he at
 length succeeded in inventing and perfecting that which has since been
 generally adopted throughout the kingdom.

 "That your petitioner's invention consists principally in introducing
 the fire into the midst of the boiler, and in making the boiler of a
 cylindrical form, which is the form best adapted for sustaining the
 pressure of high steam.

 "That the following very important advantages are derived from
 this, your petitioner's, invention. This boiler does not require
 half of the materials, nor does it occupy half the space required
 for any other boiler. No mason-work is necessary to encircle the
 boiler. Accidents by fire can never occur, as the fire is entirely
 surrounded by water, and greater duty can be performed by an engine
 with this boiler, with less than half the fuel, than has ever been
 accomplished by any engine without it. These great advantages render
 this small and portable boiler not only superior to all others used
 in mining and manufacturing, but likewise is the only one which can
 be used with success in steam-vessels or steam-engine carriages. The
 boilers in use prior to your petitioner's invention could never with
 any degree of safety or convenience be used for steam navigation,
 because they required a protection of brick and mason work around
 them, to confine the fire by which they were encircled, and it would
 have been impossible, independent of the great additional bulk and
 weight, that boilers thus constructed could withstand the rolling of
 vessels in heavy seas; and notwithstanding every precaution the danger
 of the fire bursting through the brick and mason work could never be
 effectually guarded against.

 "That had it not been for this, your petitioner's, invention, those
 vast improvements which have been made in the use of steam could not
 have taken place, inasmuch as none of the old boilers could have
 withstood a pressure of above 6 lbs. to the inch, much less a pressure
 of 60 lbs. to the inch, or even of above 150 lbs. to the inch when
 necessary.

 "That as soon as your petitioner had brought his invention into
 general use in Cornwall, and had proved to the public its immense
 utility, he was obliged in 1816 to leave England for South America
 to superintend extensive silver mines in Peru, from whence he did
 not return until October last. That at the time of your petitioner's
 departure the old boilers were falling rapidly into disuse, and when
 he returned he found they had been generally replaced by those of his
 invention, and that the saving of coals occasioned thereby during that
 period amounted in Cornwall alone to above 500,000_l._[153]

[Footnote 153: See Lean's report, vol. ii., p. 175.]

 "That the engines in Cornwall, in which county the steam-engines used
 are more powerful than those used in any other part of the kingdom,
 have now your petitioner's improved boilers, and it appears from
 the monthly reports that these engines, which in 1798 averaged only
 fourteen and half millions now average three times that duty with the
 same quantity of coals, making a saving to Cornwall alone of 2,781,264
 bushels of coals, or about 100,000_l._ per annum. And the engines
 at the Consolidated Mines in November, 1827, performed sixty-seven
 millions, being forty millions more than had been performed by Boulton
 and Watt's chosen engine at Herland, as before stated.

 "That had it not been for your petitioner's invention, the greater
 number of the Cornish mines, which produce nearly 2,000,000_l._ per
 annum, must have been abandoned in consequence of the enormous expense
 attendant on the engines previously in use.

 "That your petitioner has also invented the iron stowage water-tanks
 and iron buoys now in general use in His Majesty's navy, and with
 merchant's ships.

 "That twenty years ago your petitioner likewise invented the
 steam-carriage, and carried it into general use on iron railroads.

 "That your petitioner is the inventor of high-pressure steam-engines,
 and also of water-pressure engines now in general use.

 "That his high-pressure steam-engines work without condensing water,
 an improvement essentially necessary to portable steam-engines, and
 where condensing water cannot be procured.

 "That all the inventions above alluded to have proved of immense
 national utility, but your petitioner has not been reimbursed the
 money he has expended in perfecting his inventions. That your
 petitioner has a wife and large family who are not provided for.

 "That Parliament granted to Messrs. Boulton and Watt, after the
 expiration of their patent for fourteen years, an extension of their
 privileges as patentees for an additional period, whereby they gained,
 as your petitioner has been informed, above 200,000_l._

 "That your petitioner therefore trusts that these his own important
 inventions and improvements will not be suffered to go unrewarded
 by the English nation, particularly as he has hitherto received no
 compensation for the loss himself and his family have sustained by his
 having thus consumed his property for the public benefit.

 "Your petitioner therefore most humbly prays that your Honourable
 House will be pleased to take his case into consideration, and to
 grant him such remuneration or relief as to your Honourable House
 shall seem meet.

 "And your petitioner, as in duty bound, will ever pray, &c.

  "RD. EDMONDS,
  "_Solicitor, Penzance_."

From the Patent Office to the House of Commons was, for a petitioner,
as bad as out of the frying-pan into the fire. Trevithick solicited the
support of Members of Parliament until tired of running after friends,
and the petition became a dead letter, though the mining interests
of Cornwall had in twelve years saved 500,000_l._ by his unrewarded
inventions.

  "LAUDERDALE HOUSE, HIGHGATE, _December 24th, 1831_.

 "MR. GILBERT,

 "Sir,--I find that Mr. Spring Rice cannot get the Lords of the
 Treasury to agree to remunerate or assist me in any way. He appeared
 to be much disappointed, and said that he would write to the Admiralty
 Board on Thursday last, recommending them to adopt this engine. As yet
 I have heard nothing respecting it, nor do I expect to during the holy
 days; but in the interim I wish to look out for some moneyed man to
 join in it, otherwise I fear I shall lose the whole. Can you assist in
 recommending anyone you know? I wish Mr. Thompson would come into it,
 he would be a good man. Can you furnish me with a copy of your report
 to Mr. Spring Rice, or something relating thereto? It would be a great
 assistance in getting some one to join.

 "The sum required is small, and the risk is less; but the prospect is
 great, beyond anything I ever knew offered on such easy terms. Waiting
 your reply,

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK."

  "DEAR TREVITHICK,     "EASTBOURNE, _December 26th, 1831_.

 "I am sorry to find that you have not any prospect of assistance from
 Government. I have not any copy or memorandum of my letter to Mr.
 Spring Rice; but it was to the effect of first bearing testimony to
 the large share that you have had in almost all the improvements on
 Mr. Watt's engine, which have altogether about trebled its power; to
 your having made a travelling engine twenty-eight years ago; of your
 having invented the iron-tanks for carrying water on board ships, &c.

 "I then went on to state that the great defect in all steam-engines
 seemed to be the loss, by condensation, of all the heat rendered
 latent in the conversion of water into steam; that high-pressure
 engines owed their advantages mainly to a reduction of the relative
 temperatures of this latent heat; that I had long wished to see the
 plan of a differential engine tried, in which the temperatures and
 consequently elasticities of the fluid might be varied on the opposite
 sides of the piston, without condensation; that the engine you have
 now constructed promised to effect that object; and that, in the
 event of its succeeding at all, although it might not be applicable
 to the drawing water out of mines, yet that for steam-vessels and
 for steam-carriages its obvious advantages would be of the greatest
 importance; and I ended by saying that although it was clearly
 impossible for me to ensure the success of any plan till it had been
 actually proved by experiment, yet judging theoretically, and also
 from the imperfect trial exhibited on the Thames, I thought it well
 worthy of being pursued. Your plan unquestionably must be to associate
 some one with you (as Mr. Watt did Mr. Boulton), and I certainly think
 it a very fair speculation for any such person as Mr. Boulton to
 undertake.

 "It is impossible for me to point out any individual, as never having
 had the slightest connection with trade or with manufacture in any
 part of my life, I am entirely unacquainted with mercantile concerns.
 I cannot, however, but conjecture that you should make a fair and full
 estimate of what would be the expense of making a decisive experiment
 on a scale sufficiently large to remove all doubt; and that your
 proposal should be, that anyone willing to incur that expense should,
 in the event of success, be entitled to a certain share of your
 patent. On such conditions some man of property may perhaps be found
 who would undertake the risk; and if the experiment proves successful,
 he will be sure to use every exertion afterwards for his own sake.
 With every wish for your success,

  "Believe me,
  "Yours very sincerely and faithfully,
  "DAVIES GILBERT."

The petition to Parliament for a national payment for national gains,
so hopefully taken up on his return from America, when experience had
proved the value of his inventions, after four weary years of deferred
expectation, was consigned to the tomb of forgetfulness.

Compare the petition of 1828 with a modern report.

 "Prior to the invention of your petitioner's boiler, the most striking
 defect observable in every steam-engine was in the form of the boiler
 which in shape resembled a tilted wagon; your petitioner's invention
 consists principally in introducing the fire into the midst of the
 boiler, and in making the boiler of a cylindrical form, which is the
 form best adapted for sustaining the pressure of high steam, and does
 not require half of the materials, nor does it occupy half the space
 required for any other boiler, and greater duty can be performed by
 an engine with this boiler with less than half the fuel, than by any
 engine without it, and is the only one that can be used with success
 in steam-vessels, as none of the old boilers could have withstood a
 pressure of above 6 lbs. on the inch, much less a pressure of 60 lbs.
 or even of 150 lbs. when necessary."

A report of the Royal Mail Steam Packet Company in 1871 states, "by
placing compound engines in the 'Tasmania,' they had reduced the
consumption of coal to one-half the former quantity, doubled her
capacity for freight, and increased her speed."[154] Presuming that the
compound engines of the 'Tasmania' are like other engines known by that
name, having high-pressure steam in a comparatively small cylinder from
which it expands in a larger one, tubular boilers, surface condensers,
and screw-propeller, the saving admitted in the 'Tasmania' is just what
Trevithick's petition pointed out forty-three years ago--to lessen
by one-half the weight, space, and fuel in marine steam-engines--his
opinion being founded on the experience of a lifetime, for as early
as 1804 he wrote on the question of compound engines, "I think one
cylinder partly filled with steam would do equally as well as two
cylinders;"[155] and again in 1816, describing expansion, "The engine
is now working with 60 lbs. of steam, three-quarters of the stroke
expansive, and ends with the steam rather under atmosphere strong;"[156]
and in the same year worked the expansive compound engine at
Treskerby.[157]

[Footnote 154: See 'The Times,' October 26th, 1871, Half-yearly Report of
the Chairman.]

[Footnote 155: See vol. ii., p. 134.]

[Footnote 156: See vol. ii., p. 91.]

[Footnote 157: See vol. ii., p. 104.]




CHAPTER XXVI.

TUBULAR BOILER, SUPERHEATING STEAM, AND SURFACE CONDENSER.


  "MR. GILBERT,      "HAYLE FOUNDRY, _December 14th, 1828_.

 "Sir,--On my return from London five weeks since I was disappointed
 at not finding you in Cornwall. I have made inquiry into the duty
 performed by the best engines, and the circumstances they are under,
 from which it appears to me there is something which as yet has not
 been accounted for, particularly in Binner Downs engines. A statement
 was given to me by Captain Gregor, the chief agent and engineer of the
 mine, which appears so plain that I cannot doubt the facts, though
 they differ very widely from all former opinions. There are two
 engines, one of 42 inches diameter, the other of 70 inches diameter,
 10-feet stroke.

 "Formerly those engines worked without cylinder cases, when the
 70-inch cylinder burnt 1-1/2 wey of coal, and performed a regular duty
 of forty-one millions; since that time brickwork has been placed round
 the cylinder and steam-pipes, leaving a narrow flue, which is heated
 by separate fires. These flues consume about 5 bushels of coal in
 twenty-four hours; the heat is not so great as to injure the packing,
 which stands good for thirteen weeks; the saving for several months
 past has increased the duty to sixty-three millions.

 "Before the use of this flue 108 bushels of coal were consumed under
 the boiler, now only 67 bushels are needed, which with the 5 bushels
 in the flue gives 72 bushels. The coal burnt under the boiler gives
 a duty of sixty-six millions, or an expansion of 60 per cent. by the
 heat of 5 bushels of coal in the flues, and a duty of 1781 millions
 gained in twenty-four hours by 5 bushels of coal, which amounts to
 350 millions gained by each of these 5 bushels. The 42-inch cylinder
 is as near as possible under the same circumstances, no other
 alterations have been made; and to prove this they left out the fires
 in the flues, and the engines fell back to their former duty, and the
 condensing water increased in the same proportion.

 "The surface sides heated by this 5 bushels of coal is about 300
 surface feet, the saving effected is 1781 millions, which is six
 millions saving for each foot of surface on the castings in the flues.
 In Wheal Towan engine that did eighty-seven millions, the surface
 sides of the boiler was 1000 feet of fire-sides for every bushel of
 coal burnt in an hour, and the duty performed per minute from each
 foot of boiler fire-sides was 1500 lbs. 1 foot high. Now it appears
 that the heating of Binner Downs 300 surface feet gave a saving of
 6000 lbs. per minute per surface foot; whereas the boiler sides only
 gave 1500 lbs. of duty per minute for each foot of boiler fire-sides.
 Therefore the saving by heating the sides of the cylinder is equal
 to four times the duty done by each square foot of boiler sides;
 and further, it appears that the 300 feet, when not heated, though
 clothed round with brickwork, condensed or prevented from expanding
 the steam of 41 bushels of coals, which was eight times as much steam
 condensed as the 5 bushels of coal would raise. Now if this be a
 report of facts, which I have no reason to doubt (but still I will be
 an eye-witness to it next week), there must be an unknown propensity
 in steam above atmosphere strong to a very sudden condensation, and
 _vice versâ_, to also a sudden expansion, by a small heat applied to
 the steam-sides; and if by heating steam, independent of water, such a
 rapid expansion takes place, certainly a rapid condensation must take
 place in the same ratio, which might be done at sea by cold sides to a
 great advantage, always working with fresh water.

 "I shall have a small portable engine finished here next week, and
 will try to heat steam, independent of water, in small tubes of iron,
 on its passage from the boiler to the cylinder, and also try cold
 sides for condensing.

 "If the above statement prove to be correct, almost anything might
 be done by steam, because then additional water would not be wanted
 for portable engines, but partially condensed and again returned into
 the boiler, without any fresh supply or the incumbrance of a great
 quantity; and boilers might be made with extensive fire-sides, both
 to heat water and steam, and yet be very light.

 "It appears that this engine, when working without the heated flues
 round the cylinder and pipes, evaporated 20,000 gallons of water into
 steam, in twenty-four hours, more than when the flues were heated, and
 the increase of condensing water was in the same proportion. It is so
 unaccountable to me that I shall not be satisfied until I prove the
 fact, the result of which I will inform you, and shall be very glad to
 receive your remarks on the foregoing statement.

 "The first engine that will be finished here for Holland will be a
 36-inch cylinder, and a 36-inch water-pump, to lift water about 8 feet
 high; on the crank-shaft there is a rag-head of 8 feet diameter, going
 8 feet per second, with balls of 3 feet diameter passing through the
 water-pump, which will lift about 100 tons of water per minute. It
 is in a boat of iron, 14 feet wide, 25 feet long, 6 feet high, so as
 to be portable, and pass from one spot to another, without loss of
 time. It will drain 18 inches deep of water (the annual produce on the
 surface of each acre of land) in about twenty minutes for the drainage
 of each acre, with one bushel or sixpennyworth of coal per year. The
 engine is high pressure and condensing.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK.

 "P.S.-Woolf is making an apparatus to throw back from the bottom of
 the cylinder on to the top of the piston a fluid metal every stroke.
 He says he proved by an indicator that he raised 18,000 inches of
 steam from 1 inch of water, of 11 lbs. to the inch pressure on a
 vacuum, and that the reason why this engine did not do 300 millions,
 was because the steam passed by the sides of the piston. That an
 engine at the Consolidated Mines working 10 feet 2 inch stroke, going
 7/8ths expansive, beginning with steam of 20 lbs. to the inch above
 the atmosphere, and ending with 11 lbs. on a vacuum. I doubt this
 statement; however, there is some hidden theory as yet, because
 some engines perform double as much as others, under the same known
 circumstances, and I believe that nothing but practice will discover
 where this defect is, for, in my opinion, no statement of theory
 yet given is satisfactory why high-pressure engines so far exceed
 low-pressure engines. It is facts that prove it to be so, therefore
 all theory yet laid down must be defective."

[Illustration: MOUNT'S BAY. [W. J. Welch.]]

At the date of this letter Trevithick had been rather more than a year
in England, residing generally at Hayle, within half-a-dozen miles of
Mount's Bay, from which he had sailed for America; and after eleven
years of wandering in countries where steam-engines were unknown,
except those that he himself had constructed, was again on his return
giving his whole thoughts to the idol of his life.

During that period scientific men in Europe thought and wrote much
on the question of relative temperature, pressure, economy, and
manageability of steam. Newcomen's great discovery a century before
was the avoidance of the loss of heat by the cooling at each stroke
of the exterior of the steam-vessel of Savery's engine by injecting
cold water into the steam in the cylinder. After fifty years came the
Watt improvement, still reducing the loss of heat by removing the cold
injection-water from the steam-cylinder to a separate condenser.

The high-pressure steam-engine was perfect without injection-water,
though when convenient its use was equally applicable as in the
low-pressure engine. Trevithick, on his return to civilized life, read
the views of Watt on steam, as given in 'Farey on the Steam-Engine.'
On informing Davies Gilbert of his doubts of the accuracy of those
views, and of his intention of testing them by comparison with the
work performed by Cornish pumping engines, his friend, who had just
published his 'Observations on the Steam-Engine,'[158] forwarded a copy,
from which the following is an extract:--

[Footnote 158: 'Observations on the Steam-Engine,' by Davies Gilbert,
V.P.R.S., January 25th, 1827. See 'Philosophical Transactions.']

 "One bushel of coal, weighing 84 lbs., has been found to perform
 a duty of thirty, forty, and even fifty millions, augmenting with
 improvements, chiefly in the fire-place, which produce a more rapid
 combustion with consequently increased temperature, and a more
 complete absorption of the generated heat; in addition to expansive
 working, and to the use of steam raised considerably above atmospheric
 pressure."

Those words gave the result of Trevithick's experience made known to
his friend during twenty years of labour,[159] and yet by a seeming
fatality his name is not found in his friend's book.

[Footnote 159: See letter, vol. ii., p. 143.]

Sir John Rennie, who in youth had been employed under Boulton and Watt
at Soho, and had risen to be a member of the Royal Society, came about
that time into Cornwall, at the request of the Admiralty, to make
examination into the work performed by Cornish pumping engines, and
selected Wheal Towan engine on which to make special experiments.[160]
The subject of Trevithick's note was therefore at that period, and
still is, a matter of importance; and his practical treatment of
the question is more instructive to young engineers than complex
rules. Arthur Woolf was at the same time experimenting on steam at
the Consolidated Mines, and finding the want of agreement between
the rules of low-pressure and the practice of high-pressure engines,
imputed the error to the escape of steam by the sides of the piston.
Trevithick disbelieved this, "because some engines perform double as
much as others, under the same known circumstances," and advocated
the observance of general practice to prove why high-pressure engines
were more economical than those of low-pressure. Captain Gregor had
placed fire-flues around the steam cylinder and pipes, hoping thereby
to exceed the duty of the Wheal Towan engine, whose boiler, cylinder,
and steam-pipes were carefully clothed with a thick coating of sawdust
or other non-conductor of heat, and lifted eighty-seven millions of
pounds of water 1 foot high by the heat from a bushel of coal weighing
84 lbs. This was the greatest duty that had ever been recorded from a
steam-engine. The Trevithick or Cornish boilers, similar to those in
Dolcoath,[161] measured at the rate of 1000 superficial feet of heating
surface for each bushel of coal burnt in an hour, and in round numbers
gave a duty of 1500 lbs. lifted a foot high to each foot of boiler
surface. In words not technical, the heat from 1 lb. of coal gave steam
that raised 460 tons weight of water 1 foot high.

[Footnote 160: See vol. ii., p. 185.]

[Footnote 161: See drawing, vol. ii., p. 169.]

The cylinder of this engine used the Watt steam-jacket. The Binner
Downs engine was doing not one-half this duty, namely, forty-one
millions; when brick flues were built around the cylinder, cylinder
cover, and steam-pipes, and one or two fire-places, fixed near the
bottom of the cylinder, of a size to conveniently burn 5 bushels of
coal in twenty-four hours, the heat from which circulated through those
flues on its way to the chimney, and increased the duty of the engine
by one-half, raising it to sixty-three millions; in other words, during
twenty-four hours of working, 67 bushels of coal in the boiler, and 5
bushels in the cylinder flues, did the same work as 108 bushels in the
boiler without the cylinder flues, causing a saving of fifty per cent.
by their use. Another startling fact was the greater effect for each
foot of heating surface in the steam-cylinder flues than in the boiler
flues; the latter gave a power of 1500 lbs. raised 1 foot high by a
bushel of coal, while the former gave 6000 lbs. of power from the same
amount of coal and heating surface.

Here was a mystery that Trevithick would not believe until he had
seen it with his own eyes: he searched for it for a year or two, and
overlooking the fact that the more simply arranged engine of his once
pupil, Captain Samuel Grose, was doing more duty than the superheating
steam-engine at Binner Downs, he worked at what seemed to be new
facts, and converted them into a new engine.

We have traced how succeeding engineers tried to prevent loss of heat.
Trevithick took the first bold step, and aiming at the same object,
made the boiler the steam-jacket for the cylinder, and in his patent
of 1802 went still further and protected the boiler from external
cold, and thus describes it:--"The steam which escapes in this engine
is made to circulate in the case round the boiler, where it prevents
the external atmosphere from affecting the temperature of the included
water, and affords by its partial condensation a supply for the boiler
itself."[162] So that a quarter of a century before the date of those
Binner Downs experiments he had patented an engine having neither
cylinder nor boiler exposed to the cooling atmosphere. The flues around
the Binner Downs cylinder were difficult of control. Trevithick says
the piston packing had not been injured, showing that observers thought
it would be, and even the cylinder was endangered, for the writer,
who stoked those heating flues, recollects the fires burning very
brightly in them. The ready transmission of heat through thin metal,
used by Trevithick in 1802 for heating feed-water, and in the cellular
bottom of the iron ship of 1808, serving as a surface condenser,[163]
and his experience in 1812, that "the cold sides of the condenser
are sufficient to work an engine a great many strokes without any
injection,"[164] still followed up in 1828 by condensing steam without
the use of injection-water, led to what is since known as Hall's
surface condenser.

[Footnote 162: See patent specification, vol. i., p. 132.]

[Footnote 163: See vol. i., p. 335.]

[Footnote 164: See Trevithick's letter, 7th December, 1812, vol. ii., p.
18.]

The following letter is in the handwriting of the present writer;
it is the only one of Trevithick's numerous letters not written by
himself:--

  "MR. GILBERT, "HAYLE, _December 30th, 1828_.

 "Sir,--On the 28th inst. I received your printed report on steam, and
 have examined Farey's publication on sundry experiments made by Mr.
 Watt, which are very far from agreeing with the actual performance
 of the engines at Binner Downs. Mr. Watt says that steam at one
 atmosphere pressure expands 1700 times its own bulk as water at 212°,
 and that large engines ought to perform eighteen millions when loaded
 with 10 lbs. to the inch of actual work, the amount of condensing
 water being one-fortieth part of the content of the steam in the
 cylinder at one atmosphere strength, the cold condensing water at 50°,
 and when heated 100°. This would give for the Binner Downs engine,
 with a 70-inch cylinder, 10-inch stroke, 11 lbs. effective work on the
 inch (this load being one-tenth more than in Watt's table, by Farey,
 for an engine of this size and stroke), 57 gallons of injection-water
 for each stroke, and when working eight strokes per minute, to do
 eighteen millions would consume 11-1/4 bushels of coal per hour.

 "Now the actual fact at Binner Downs, at the rate of working and power
 above mentioned, is that 3 bushels of coal per hour were burnt, using
 13 gallons of injection-water at each stroke at 70° of heat, which was
 raised by its use to 104°, or an increase of 34°, which, multiplied by
 13 gallons, gives 442. Mr. Watt's table for this engine and work gives
 57 gallons of condensing water at 50°, heated by use to 100°. This 50°
 raised, multiplied by the 57 gallons of water, amounts to 2850, or six
 and a half times the quantity really used in the Binner Downs engine,
 and nearly four times the coal actually used at present. Mr. Watt
 further says that steam of 15 lbs. to the inch, or one atmosphere,
 from 1 inch of water at 212° occupies 1170 inches, and that steam of
 four atmospheres, or 60 lbs. to the inch, gives only 471 inches at a
 heat of 293°. Now deducting 50° from 212° leaves 162° of heat raised
 by the fire. Multiply 15 lbs. to the inch by 1700 inches of steam,
 and divide it by 162°, gives 138°, whereas if you deduct 50° from
 293°, it leaves the increase of heat by the fire 243°. Steam of 60
 lbs. to the inch multiplied by 471, being the inches of steam made
 by 1 inch of water divided by 243°, the degrees of heat raised by the
 coal, gives a product of 116; therefore, by Mr. Watt's view it appears
 that low steam would do one-fifth more duty than high steam, and yet
 Binner Downs engine in actual work performs about four times the duty
 given by Mr. Watt's theory and practice, with only one-sixth part of
 the amount of heat carried off by the condensing water, proving that
 high steam has much less heat, in proportion to its effective force;
 and this is further proved by the small quantity of condensing water
 required to extract its heat.

 "Yesterday I proved this 70-inch cylinder while working with the
 fire-flues round it, which flues only consumed 5 bushels of coal in
 twenty-four hours. The engine worked eight strokes a minute, 10-feet
 stroke, 11 lbs. to the inch effective force on the piston; steam in
 the boiler 45 lbs. above the atmosphere, consuming 12 bushels of
 coal in four hours, using 13 gallons of condensing water at each
 stroke, which was heated from 70° to 104°; but when the fires round
 the cylinder were not kept up, though still having the casing of hot
 brickwork around it, and performing the same work, burnt 17 bushels
 of coal in the same time of four hours, and required 15-1/2 gallons
 of condensing water, which was heated from 70° to 112°. You will find
 that the increased consumption of coal, by removing the fire from
 around the cylinder, was nearly in the same proportion as the increase
 and temperature of the condensing water, showing the experiment to be
 nearly correct.

 "From the general reports of the working of the engines it appears
 that when the surface sides of the castings are heated, either by hot
 air or high steam, the duty increases nearly fifty per cent. from this
 circumstance alone.

 "A further proof of the more easy condensation of high steam was in
 the Binner Downs 42-inch cylinder engine, 9-feet stroke, six strokes
 per minute, 11 lbs. effective power on each inch, burning 1-1/3
 bushel of coal an hour. In this engine the proportion of saving by
 the heating flues was the same as in the large engine. I tried to
 condense the steam by the cold sides of the condenser, without using
 injection-water. The water in the condenser cistern was at 50°.
 After working for twenty-five minutes the small quantity of hot water
 discharged at the top of the air-pump reached 130° of heat, but then
 would rise no higher, the cold sides of the condenser being equal to
 the condensation of all the steam. The eduction-pipe and air-pump,
 with its bottom and top, gave 60 feet of surface sides of thick
 cast iron, and about 20 feet more of surface sides of a thin copper
 condenser; altogether, 80 feet of surface cold sides, surrounded by
 cold water. About half a pound on the inch was lost in the vacuum, the
 discharged water being 130° of heat instead of 100°. The vacuum was
 made imperfect by about 1-1/2 lb. to the inch.

 "It is my opinion that high steam will expand and contract with a much
 less degree of heat or cold in proportion to its effect, than what
 steam of atmosphere strong will do. I intend to try steam of five
 or six atmospheres strong, and partially condense it down to nearly
 one atmosphere strong, and then by an air-pump of more content than
 is usual to return the steam, air, and water, from the top of the
 air-pump, all back into the boiler again, above the water-level in
 the boiler, and by a great number of small tubes, with greatly heated
 surface sides, to reheat the returned steam; though by this plan I
 shall lose the power of the vacuum, and also the power required on the
 air-bucket to force the steam and water back again into the boiler,
 yet by returning so much heat I shall over-balance the loss of power,
 besides having a continued supply of water, which in portable engines,
 either on the road or on the sea, will be of great value.

 "I shall esteem it a very great favour if you will be so good as to
 turn over in your mind the probable theory of those statements, and
 give me your opinion. If Mr. Watt's reports of his experiments are
 correct, how is it possible that the high-pressure engine that I built
 at the Herland thirteen years ago, which discharged the steam in open
 air, did more than twenty-eight millions? If you wish, I will send a
 copy of the certificate of the duty done by this engine, which states
 very minutely every circumstance. Now that cylinder, with every part
 of the engine, was exposed to the cold; had it been heated around
 those surfaces, as on the present plan, it would have done above forty
 millions.

 "Suppose the Binner Downs 70-inch cylinder engine, 10-feet stroke,
 working with full steam to the bottom of the stroke, when, by the
 experiment, the heated flues were again laid on would have worked
 one-third expansive, by the heat of 5 bushels of coal around the
 cylinder. Now one-third of the power would make a 3 feet 4 inch
 stroke, 11 lbs. to the inch effective power, eight strokes a minute,
 during twenty-four hours, by the consumption of 5 bushels of coal
 applied on the surface sides of the cylinder, performing a duty of 324
 millions with a bushel of coal. Now suppose the cylinder without the
 heating flues had the steam cut off at two-thirds of the stroke, and
 that it is possible in a moment to heat the cylinder by the flues; in
 that case the steam would, by its expansion from the hot sides, fill
 the last third of the cylinder to the bottom of the stroke; then if
 that steam could be suddenly cooled, so as to contract it one-third,
 the piston would ascend one-third its stroke in the cylinder; and it
 appears in theory by this plan, that a cylinder once filled two-thirds
 full of steam, by receiving the heat on its surface sides from 5
 bushels of coal, and again suddenly cooling down, would continue to
 work for ever, without removing the steam from the cylinder, and
 would perform a duty of 324 millions. This never can be accomplished
 in practice in this way, but the effect may be obtained by partially
 condensing in a suitable condenser, and again heating by hot sides.

 "This mystery ought to be laid open by experiment, for what I have
 stated are plain facts from actual proofs, and I have no doubt that
 time will show that the theory of Mr. Watt is incorrect. Though there
 were 300 feet of cold sides, yet 200 feet were not condensing steam,
 because on the return of the piston, what was condensed below, and
 while the engine was resting, did not make against it more than what
 was condensed above the piston on its descent; therefore you may count
 on 150 feet of cold external sides constantly condensing, that made
 this third-part difference against the expansion of the steam.

  "I remain, Sir,
  "Your very humble servant,
  "RICHD. TREVITHICK."

The writer's note-book used during those experiments is in his
possession, as well as Trevithick's note-book giving particulars of
experiments at several mines, from which the following extracts are
taken:--

 "CORNWALL, _August, 1828_.--Wheal Towan 80-inch cylinder,
 10-feet stroke, 6·9 strokes per minute, loaded to 9·5 lbs. on the inch
 of the piston, with three of Trevithick's boilers, each 37 feet long,
 6 feet 2 inches diameter, with fire-tube 3 feet 9 inches diameter,
 fire-place 6 feet long, evaporated 13 square feet of water with 1
 bushel of coal,[165] duty 87 millions. The heat in the stack was just
 the same as the heat of the steam in the boiler. Another engine of
 the same size on the same mine, with similar boilers, but working
 only 4·06 strokes per minute, loaded to 4·55 lbs. on each inch of the
 piston, did 50·8 millions.

 [Footnote 165: 84 lbs.]

 "Wheal Vor 53-inch cylinder, 9-feet stroke, 6·59 strokes per minute,
 loaded to 19·58 lbs. on each square inch of the piston, did 36·6
 millions.

 "Wheal Damsel 41-inch cylinder, 7 feet 6 inch stroke, 5·52 strokes per
 minute, loaded to 21·5 lbs. on the inch of the piston, did 33 millions.

 "It would appear, therefore, that about 10 lbs. to the inch on the
 piston allows of the best duty, and that a 10-feet stroke exceeds in
 duty a 7 feet 6 inch stroke.

 "The Wheal Towan engine, doing 87 millions, had 1248 feet of tube
 fire-surface, and a similar amount of external boiler surface in the
 flues. 2-1/2 bushels of coal were consumed each hour, giving about
 1000 feet of fire-sides for each bushel of coal consumed per hour, and
 50 feet of fire-bars. Those boilers were intended to supply steam for
 working the engine at ten strokes a minute; a bushel of coal an hour
 would in that case have had 600 feet of boiler fire-surface.

 "Binner Downs 70-inch cylinder, 10-feet stroke, did 41 millions. A
 fire was then put around the cylinder and steam-pipes, which burnt 5
 bushels of coal in twenty-four hours, by which the duty was increased
 to 63 millions. The surface sides of the cylinder, cylinder-top,
 and steam-pipes heated by flues was 300 feet, and caused a saving of
 41 bushels of coal in twenty-four hours. Another engine in the same
 mine was tried, having a 42-inch cylinder; when the fire was around
 the cylinder, she worked 100 strokes without injection-water; the
 expansion-valve was closed at half-stroke, the steam in the boiler 56
 lbs. on the inch above the atmosphere."

It is not easy to deal with the important reasonings flowing from
those facts, and influencing the form and economy of the steam-engine,
nor to show if Trevithick was right in discrediting the laws laid
down by Watt. Newcomen's engine had the interior, as well as the
exterior of the steam-cylinder exposed to the cooling atmosphere.
Watt, by putting a cover on the cylinder, reduced the loss of the
heat from the interior, and by his steam-case hoped to reduce the
loss from the exterior, though by it he increased the amount of
surface exposed to the cold. In Trevithick's early engines the boiler
alone exposed heat-losing surface, and this was further reduced by
its own comparatively small size, the engine and boiler complete not
exposing one-quarter of the surface of a Watt low-pressure engine of
equal power. One object of the Binner Downs experiment was to further
curtail this loss of power by increasing the heat of the steam while in
operation in the cylinder, since called superheating steam.

This principle of giving increased heat to steam, after it had left
its state as water, was made practical by Trevithick's boiler at Wheal
Prosper in 1810, where the flues having first been carried around the
water portion of the boiler, then passed over the steam portion;[166]
and again in the upright boiler of 1815, having the upper end of the
fire-tube surrounded by steam above the water line.[167] Those early
beginnings of superheating steam and surface condensation culminated
in the Binner Downs experiments of 1828, one immediate practical result
of which was the tubular surface condenser, enabling steamboat boilers
to avoid, in a great measure, the use of salt water, facilitating in a
marked degree the application of marine boilers and engines with steam
of an increased pressure.

[Footnote 166: See vol. ii., p. 71.]

[Footnote 167: See vol. i., p 354.]

The Binner Downs engine, with a cylinder of 70 inches in diameter,
and a stroke of 10 feet when working with steam in the boilers of 45
lbs. to the square inch above the atmosphere, and using the heating
flues around the cylinder, required 13 gallons of injection-water at
each stroke, and consumed at the rate of 3 bushels of coal an hour, to
produce a duty equal to eighteen millions; by removing the cylinder
superheating flues, the quantity of injection-water for the same amount
of work increased to 15-1/2 gallons, and the coal to 4-1/4 bushels.
Watt's rule for his low-pressure steam vacuum engine doing a duty of
eighteen millions, gave 57 gallons of injection-water, and 11-1/4
bushels of coal.

On the question of coal, this statement agrees very nearly with
Trevithick's letters of sixteen years before, when he used the
high-pressure boilers in the Dolcoath pumping engine,[168] promising that
his high-pressure expansive engine would do the work with one-third of
the coal required in the low-pressure vacuum engine.

[Footnote 168: See vol. ii., p. 171.]

The high-pressure steam required a less amount of injection-water to
condense it than the low-pressure steam, in proportion to the work
done, showing the Watt rule and the Watt experience to be inapplicable
to high-pressure engines; for instead of 57 gallons of injection-water
the Binner Downs engine with steam of 45 lbs. to the inch required
but 15-1/2 gallons of injection-water, and this amount was further
reduced to 13 gallons by superheating the steam; this roughly agrees
with the coal consumed, or in other words, with the amount of heat
to be carried off by injection-water: the Watt rule giving 11-1/4
bushels as the fair allowance for low-pressure steam vacuum engines,
while the high-pressure steam vacuum engine burnt but 4-1/4 bushels.
This was further reduced to 3 bushels by superheating. Those facts led
to the idea that if the steam pressure was sufficiently increased,
condensation might be carried out without any injection-water, by
the transmission of the heat in the steam through the metal sides
of the condenser. An experiment was at once made by removing the
Watt condenser and injection-water, as he had done seventeen years
before,[169] using in their stead a thin copper surface-condenser
immersed in cold water, producing, within 1/2 lb. on the inch, as good
a vacuum as when injection-water was used, leading to the conclusion,--

[Footnote 169: See Query 3rd, vol. ii., p. 19.]

 "It is my opinion that high steam will expand and contract with a much
 less degree of heat or cold, in proportion to its effect, than what
 steam of atmosphere strong will do. I intend to try steam of five or
 six atmospheres strong, and partially condense it down to nearly one
 atmosphere strong, and then by an air-pump of more content than is
 usual to return the steam, air, and water back into the boiler again,
 and by a great number of small tubes, with greatly heated surface
 sides, to reheat the returned steam."

This, in practical words, is the surface condenser by which the used
steam is returned to the boiler in the form of water. The more general
use of high-pressure steam of 70 or 90 lbs. to the inch, increasing its
expansive force on one side of the piston by superheating it on its
passage through numbers of small tubes, and decreasing its expansive
force on the other side of the piston by cooling it in passage through
similar tubes exposed to cold, is partly effected in steamboats, but
has not yet been attempted in engines on the road.

After a month's further consideration he wrote:--

 "Wheal Towan engine is working with three boilers, all of the
 same size, and the strong steam from the boilers going to the
 cylinder-case; the boilers are so low as to admit the condensed
 water to run back from the case again into the boiler: they find
 that this water is sufficient to feed one of these boilers without
 any other feed-water, therefore one-third of the steam generated
 must be condensed by the cold sides of the cylinder-case, and this
 agrees with the experiments I sent to you from Binner Downs. Wheal
 Towan engine has an 80-inch cylinder, and requires 72 bushels of
 coal in twenty-four hours, therefore, the cylinder-case must, in
 condensing high-pressure steam, use 24 bushels of coal in twenty-four
 hours. Boulton and Watt's case for a 63-inch cylinder working with
 low-pressure steam, condensed only 4-1/2 bushels of coal in equal
 time, the proportions of surface being as 190 to 240 in Wheal Towan.
 Nearly five times the quantity was condensed of high steam than of low
 steam, proving that there is a theory yet unaccounted for."[170]

[Footnote 170: See Trevithick's letter, January 24th, 1829, vol. ii., p.
368.]

These apparent facts are, in the case of steamboats, more culpably
overlooked now than when he wrote forty-two years ago; engines have
been examined and reported on by eminent scientific men, but it was
left for Trevithick to point out that cold on the surface of the
steam-case of a Watt low-pressure steam vacuum engine condensed about
one-fifteenth of the steam given from the boilers, and that the loss
from exposure to cold was nearly five times more from high-pressure
steam than from low-pressure. Within a few more months he determined
on constructing an engine for the purpose of more accurately testing
those views.

  "MR. GILBERT,        "HAYLE FOUNDRY, _July 27th, 1829_.

 "Sir,--Below you have a sketch of the engine that I am making here for
 the express purpose of experimenting on the working the same steam and
 water over and over again, heating the returned steam by passing it in
 small streams up through the hot water from the bottom of the boiler.
 The boiler is 3 feet in diameter, standing perpendicular; the interior
 fire-tube is 2 feet in diameter; there is a steam-case round the
 outside of the boiler with a 1-1/2-inch space. This keeps the boiler
 hot and partially condenses the steam before it is again forced into
 the boiler.

 [Illustration]

 "The boiler is 15 feet high; the cylinder 14 inches diameter, with a
 6-feet stroke, single power. The pump for forcing the steam and water
 back again is 10 inches in diameter, with a 2 feet 9 inch stroke,
 about one-quarter part of the content of the steam-cylinder. The
 bottom of the boiler will have a great number of small holes, about
 1/16th of an inch in diameter, through which the steam delivered into
 the boiler will pass up through the hot water, by which I should
 think it will heat those small streams of steam again to their usual
 temperature.

 "The pump for lifting water to prove the duty of the engine is 30
 inches in diameter, with a 6-feet stroke, but this may be lengthened
 to a 12-feet lift, as the trial or load in the experiments may
 require, giving from 12 to 24 lbs. to the inch in the piston. This
 machine will be ready before your return to Cornwall, and I intend to
 prove it effectually before I go to Holland.

 "The Holland engine lifted on the trial, when they came down to see
 it, 7200 gallons of water a minute 10 feet high with 1 bushel of coal
 an hour; exceedingly good duty for a small engine of 24-inch cylinder,
 being 34,560,000 of duty.

 "On the 17th August the trial comes on between the two companies
 about the quays. They are as desperate as possible on both sides,
 and castings and every other article are thrown down to 30 per cent.
 below cost price; iron pumps for 6_s._ 6_d._ per cwt., and coal sold
 to the mines for 37_s._ 3_d._ per wey, when 48_s._ per wey on board
 ship was paid for it. Several thousands lost per year by each party.
 This never can last long. If you can think of any improvement I shall
 be very glad to hear in time, before it may be too late to adopt it.
 At all events, if it is not too much trouble to write, I shall be very
 glad to hear from you. What effect do you think the water will have
 in heating the steam on its passage to the top of the water from the
 false bottom of the boiler?

 "I have a cistern of cold water, with a proper condenser in it,
 connected between the bottom of the boiler-case and the force-pump
 to the bottom of the boiler, therefore I can partially condense by
 cold water sides, or by cold air sides just as I please, by rising or
 sinking the water in the cistern.

 "The boiler is made very strong to try different temperatures, and
 an additional length to the water-pump makes all very suitable for a
 great number of experiments, and if there is any good in the thing I
 will bring it out.

 "I shall have indicators at different places to prove what advantages
 can be gained. I hope to have the pleasure of your company during
 those experiments, which I think will throw more light on this
 subject than ever has yet been done. Some trials since I last wrote
 to you make me very confident that much good will arise from these
 experiments, but to what extent is uncertain.

  "I remain, Sir,
  "Your most obedient servant,
  "RICHARD TREVITHICK."

Trevithick did not use letters to illustrate his sketch, knowing that
Davies Gilbert would comprehend it; but the reader of to-day may not
find it so easy, therefore the writer has added them with a slight
detail description, he having been Trevithick's daily companion when
those drawings and experiments were made. _a_, top of boiler; _b_,
water line; _c_, centre of wheel; _d_, cast-iron wheel and chain; _e_,
chimney, 13 in. in diameter; _f_, fire-tube, 2 ft. diameter; _g_, outer
boiler-*case, 3 ft. diameter, 15 ft. long; _h_, water space of 6 in.;
_i_, boiler steam-case, 3 ft. 4 in. diameter; _j_, small holes through
which steam and water are forced into the boiler; _k_, force-pump, 10
in. diameter, 2 ft. 9 in. stroke; _l_, steam-cylinder, 14 in. diameter,
6-ft. stroke; _m_, piston-rod; _n_, fire-door; _o_, fire-bars; _p_,
pump for testing the power of the engine.

There is a natural tendency in men of genius to unwittingly return,
under new forms, to old ideas. The ideas are similar, though in
combination with new forms and new acquirements; even the outline of
this 1828 boiler, with the exception of its outer steam-casing, is
very like that in a letter to Davies Gilbert fourteen years before,[171]
of which Trevithick had kept no copy. When in the foregoing letter
he wrote, "There is a steam-case round the outside with a 1-1/2-inch
space; this keeps the boiler hot and partially condenses the steam
before it is again forced into the boiler," he had forgotten that
twenty-seven years before, when constructing his first high-pressure
steam-engines, he thus specified his invention:--"The steam which
escapes in this engine is made to circulate in the case round the
boiler, where it prevents the external atmosphere from affecting
the temperature of the included water, and affords by its partial
condensation a supply for the boiler itself."[172]

[Footnote 171: See Trevithick's letter, 7th May, 1815, vol. i., p. 364.]

[Footnote 172: See patent specification of 1802, vol. i., p. 128.]

Not one of his numerous patent specifications has been found among his
papers, neither do his letters refer to them; probably he never read
them after the first necessary examinations.

  "MR. GILBERT,      "HAYLE FOUNDRY, _November 5th, 1829_.

 "Sir,--The engine has been worked. The result is ten strokes per
 minute, 6-feet stroke, with half a bushel of coal per hour, lifting
 six thousand pounds weight. This was done with water in the cistern
 round the condenser, which water came up to 180 degrees of heat, and
 remained so. The water sides of the condenser covered with this hot
 water was 50 surface feet. I tried it to work with the cold air sides,
 but I found that the cold air sides of 120 feet would only work it
 four strokes per minute. I should have worked the steam much higher
 than 50 lbs. to the inch, but being an old boiler I thought it a risk.
 I am now placing an old boiler of 350 feet of cold sides more to the
 condenser, to give a fair trial to condensing with cold sides alone.
 The steam below the piston was about 6 or 7 lbs. to the inch above
 the atmosphere. The force-pump to the boiler was about one-fifth part
 of the content of the cylinder, and the valve close to the boiler
 lifted when the force-piston was down about two-thirds of its stroke,
 at which time the returned steam entered the boiler again. I have
 no doubt of doing near ten times the duty that is now done on board
 ships, without using salt water in the boiler, as at present. Our
 boiler has been working three days and the water has not sunk 1 inch
 per day. I am quite satisfied the trial will be a great success.

 "Mr. Praed and Sir John St. Aubyn are anxious to get a high bank
 carried out from Chapel Angel to 15 feet below low-water mark on the
 bar, to make Hayle a floating harbour.

 "I have proposed to make a sand-lifting engine. When I built that
 engine for deepening Woolwich Harbour, we lifted 300 tons per hour
 through 36 feet of water, and 20 feet above water, 56 feet above the
 bottom. This was done with two bushels of coal per hour, therefore it
 will not cost above one penny per square fathom to lift the sand over
 this embankment. It is intended to get down Mr. Telford to give his
 opinion on it. Your remarks on it would be of service.

  "I remain, Sir,
  "Your humble servant,
  "RICHARD TREVITHICK."

The writer having worked at these experiments, knows that their
object was to employ high-pressure steam in the boiler, using it very
expansively in the cylinder, and by cold surface sides reducing its
bulk either to low-pressure steam or boiling water, and then force it
again into the boiler.

  "MR. GILBERT,      "HAYLE FOUNDRY, _November 14th, 1829_.

 "Sir,--I have both of your letters and sketches, which shall be put
 in hand. I understand it perfectly well. Since I wrote to you last
 I have made several satisfactory trials of the engine, and think it
 unnecessary to make any further experiments. The statement below may
 be depended on for a future data. The load of the engine was 6280
 lbs., being 20 lbs. to the inch for a 20-inch cylinder with a 6-feet
 stroke, 12 strokes per minute, with three-quarters of a bushel of
 coals per hour, giving a duty of 361,728,000 for 1 bushel of coal, a
 duty far beyond anything done in the county by so small an engine. The
 cold water sides round the condenser was 60 feet, and the water at 112
 degrees temperature, not having a sufficient stream of cold water to
 supply the cistern. Each foot of cold water sides did 7536 lbs. per
 minute, about three times the work done in the county per foot of hot
 boiler sides; therefore the condenser need not be more than one-third
 of the boiler sides. By making the condenser of 4-inch copper tubes
 and of an inch thick, it would stand in one-twentieth part of the
 space of the boiler.

 "I put a boiler naked to try cold air sides; it was very rusty, and
 did not condense as fast as I expected. The engine worked exceedingly
 well, but slow. The duty performed for each foot of cold air sides
 was 565 lbs. per minute, about one-thirteenth part of the condensing
 of cold water sides. We never wanted to get the steam above 60 lbs. to
 the inch. I have no doubt but that copper pipes of 1/32nd of an inch
 thick, clean and small, would do considerably more, because the hot
 water that came out of the boiler from the condensed steam was but 170
 decrees, and the external sides the same heat when the steam was 15
 lbs. above the atmosphere in the condensing boiler. This boiler was 4
 feet 6 inches diameter, and I think that towards the external sides of
 the boiler there was a colder atmosphere, if I may call it so, than
 what it was in the middle of this large condensing boiler, because I
 found by trying a small tin tube, that it would condense 1500 lbs. for
 each foot of cold air sides.

 "However, as it is, it will do exceedingly well for portable purposes.

 "The duty, I doubt not, will be, both for water and air sides
 condensing, at least 50 per cent. above our Cornish engines, which
 will be above four times what is now done with ships' engines,
 especially when you take into consideration their getting steam from
 salt water, and letting out so much water from the boiler to prevent
 the salt from accumulating in the boiler, which will make 30 per cent.
 more in its favour.

 "If strong boilers to stand 200 lbs. to the inch are made with small
 tubes, I have no doubt but that the duty would be considerably more,
 and my engines will not be one-quarter part of the weight, price, or
 space of others; and when every advantage is taken it will be 1000 per
 cent. superior in saving of coal to those now at work on board. This
 engine works well, and returns the steam very regularly every stroke
 into the boiler.

 "I am extremely sorry you were not present to see these experiments.
 Please make your remarks on these statements, with any further
 information you may judge useful.

 "I shall now make drawings agreeable to my experiments for actual
 performance on board ships. In hope of hearing from you soon,

  "I remain, Sir,
  "Your very humble servant,
  "RICHD. TREVITHICK."

The large old boilers used as surface condensers, in which the steam
was partially condensed by the transmission of heat to the external
atmosphere, together with its further condensation in a smaller
condenser with cold water around it, so reduced its expansiveness,
that a large feed-pump drew the hot water and steam from the small
condenser, and forced it back into the boiler without any reduction of
quantity; those temporary contrivances, almost immediately resolved
themselves into a condenser made of copper tubes surrounded by cold
water.

Having proved by six months' experiment on a working scale the
practicability of the plan which in reality he had invented twenty
years before in the iron steamship,[173] he wrote in June, 1830:--

[Footnote 173: Drawing of iron steamship, vol. i., p. 336.]

 "TO THE RIGHT HONOURABLE THE LORDS COMMISSIONERS OF THE
 ADMIRALTY, &c., &c., &c.

 "MY LORDS,

 "About one year since I had the honour of attending your honourable
 Board with proposed plans for the improvement of steam navigation,
 and as you expressed a wish to see it accomplished, I immediately
 made an engine of considerable power for the express purpose of
 proving by practice what I then advanced in theory. I humbly request
 your lordships will grant me the loan of a vessel of about 200 or
 300 tons burthen, in which I will fix at my own expense and risk an
 engine of suitable power to propel the same at the speed required:
 no alterations whatever in the vessel will be necessary. When under
 sail the propelling apparatus can be removed, and when propelled by
 steam alone, the apparatus outside the ship will scarcely receive any
 shock from a heavy sea. This new invention entirely removes the great
 objection of feeding the boiler with salt water."

This petition was backed by Mr. Gilbert and Mr. George Rennie. His old
friend Mr. Mills took an interest in it, and wrote, "I am going to meet
Captain Symonds at Woolwich again to-morrow, and hope to be able to
persuade him to use his influence with Sir T. Hardy,"

  "LAUDERDALE HOUSE, HIGHGATE,

  "MR. GILBERT,         "_August 19th, 1830_.

 "Sir,--The boiler with the fire-place, cold air tubes outside the
 boiler but within the steam-case, fire-tubes in the boiler from the
 top of the fire-place to the top of the boiler, the ash-pit close,
 except a small door to clear out the ashes.

 [Illustration: FIG. 1.--PLAN SECTION.]

 [Illustration: FIG. 2.--ELEVATION SECTION.[174]]

 [Footnote 174: _a_, steam-case; _b_, boiler-case; _c_, space for
 condensation of steam; _d_, water and steam space; _e_, fire-tubes;
 _f_, fire-box; _g_, fire-door; _h_, fire-bars; _i_, ash-box; _j_,
 ash-box door; _k_, air-tubes in condenser; _l_, chimney; _m_, water
 level; a smoke-jack fan draught.]

 "The design is for the cold air to pass down from the top of the
 boiler through the air-tubes within the steam-case surrounding the
 boilers, becoming heated in its passage by condensing the steam in the
 case, and then to pass up through the fire-bars in, the hot state,
 nearly as hot as the steam in the case; because this air, heated to
 nearly 212 degrees by condensing the steam in its passage without any
 of its oxygen being burnt, it will not carry off so much heat from the
 fire as cold air would, and still have the same oxygen as cold air to
 consume the coal.

 "The cold air will be passing down the steam-case in the air-tubes,
 and up through the fire and fire-tubes in the boiler. I find by
 experiments I have made here, by placing a tin tube 2-1/2 inches in
 diameter, 4 feet long, inside a 4-inch tube of the same length, having
 boiling water and steam between the tubes, kept hot by a fire round
 the outer tube, with a smith's bellows blowing in at the bottom of
 the inside tube, having 2-2/3rds surface feet of condensing sides,
 measuring the inside, where the air is passing up from the bellows,
 heats from 60 to 134 degrees 15 square feet of cold air per minute.
 When you compare the effective heat of 74 degrees given to 15 cubic
 feet of air every minute from 2-2/3rds surface feet of tin plate, and
 the heat contained in 15 cubic feet of air charged with 74 degrees of
 effective heat, compared with steam of atmosphere strong, you will
 find that the condensing power of surface sides is very great, and for
 locomotive purposes might be carried still further, by forcing the air
 more quickly through the tubes. If the statements on air given in some
 books that I have read are correct, that there is about three times
 as much heat in 1 gallon of steam of atmosphere strong as there is in
 1 gallon of air of 212 degrees of heat, in that case 1 surface foot
 of tin-plate sides of this pipe, by sending off the hot air before
 described, would take out the heat of 1-1/2 cubic foot of steam per
 minute of atmosphere strong, which in the common condensing engine
 would be equal to a duty of 2700 lbs. lifted 1 foot high per minute;
 but in the high-pressure expansive engine, the heat of 1-1/2 cubic
 foot of steam would give a duty of 10,800 lbs., or four times the duty
 of the Boulton and Watt engine.

 "If you calculate on the air being heated to nearly 212 degrees before
 it enters the fire, together with the heat given to the sides of the
 boiler, the fuel saved will be above one-half on what has been done
 by the high-pressure engines in Cornwall, because at present the coal
 must pay for heating the cold air, therefore a less proportion goes
 through the sides of the boiler, and is lost through the chimney;
 whereas if the heat of the steam, by passing into the cold air, on
 its way through the condenser tubes, is carried into the fire-place,
 one-half of the coal must be saved; and you will find by calculation
 that the quantity of air required to burn the coal, and also to
 condense the steam, goes exactly in proper proportion for each other,
 and for locomotive engines with a blast will go hand-in-hand almost
 to any extent, and the size of an engine, for its power, is a mere
 nothing.

 "A smoke-jack fan in the ash-pit under the fire-bars, worked by the
 engine, would draw air down the condensing tubes, and force it up
 through the fire and fire-tubes always with the speed required, as the
 steam and the condensation would increase in the same ratio.

 "As it is possible to blow so much cold air into a fire as to put it
 out, by first heating the air it would burn all the stronger, and
 whatever heat is taken out of the condenser into the fire-place from
 the steam that has been made use of, half this extra heat will go
 into the boiler again, or in other words, but half the quantity of
 cold will be put into the fire, being the same in effect as saving
 fuel. Taking heat from the condenser through the boiler sides is an
 additional new principle in this engine. I find by blowing through
 tubes that the condensation of a surface foot of air-tube against a
 surface foot of boiler fire-tube is greater than the fire that passes
 through the boiler sides, where the common chimney draught is used, by
 nearly double; but I expect when both air and fire tubes are forced
 by a strong current of air it will be nearly equal, and the increase
 of steam and of condensation can be increased by an increased current
 of air, so as to cause a surface foot of fire and of air sides to do
 perhaps five times as much; and of course the machine will be lighter
 in proportion. I think air sides condensation preferable to water
 sides, as so small a space does the work, and is always convenient,
 and its power uniformly increasing with its speed, by the increased
 quantity of air, without the weight of water vessels. This kind of
 engine can be made to suit every place and purpose, and I think such
 an engine of the weight of a Boulton and Watt engine will perform
 twenty times the duty.

 "Air sides condensation will be advantageous on board ship, because
 there are holes for the passage of water through the bottom and sides
 of the ship.

 "I am anxious to have your opinion on this plan of returning the hot
 air from the condenser to the fire-place, and what you think the
 effect will be.

 "The Comptroller of the Navy has not yet returned from Plymouth,
 therefore no answer has been given to me.

 "You will see by the sketch how very small and compact an engine is
 now brought without complication or difficulty; each surface foot of
 boiler and condenser is equal to one-third of a horse-power, weighing
 20 lbs., or 60 lbs. weight for each horse-power. The consumption of
 fuel is so small when working a differential engine, that I expect it
 will not exceed 1 lb. of coal per hour for each horse-power.

 "The cost of erection and required room are so small from its
 simplicity that it will be generally used. As I am very anxious that
 every possible improvement should be considered prior to making a
 specification for a patent, I must beg that you will have the goodness
 to consider and calculate on the data I have given you. I am sorry to
 trouble you, but I am satisfied this will be to you rather a pleasing
 amusement than a trouble. The warming machines will take a very
 extensive run, and I believe will pay exceedingly well.

 "I am almost in the mind to take a ride down to see you in a few days,
 but am now detained here about the American mining concerns.

  "I remain, Sir,
  "Your very humble servant,
  "RD. TREVITHICK."

The letters and foot-note are the only changes made by the writer
in Trevithick's original sketch so descriptive of a wonderful
application of varied and improved principles of long-known difficulty
and importance; the beautifully compact tubular boiler for giving
high-pressure superheated steam, surface condensation, absence of
feed and condensing water, and return of the heat, in other engines
wasted in condensation, to the fire-place; though there is little or
no mention of the mechanical or moving parts of the steam-engine, yet
its vital principles are grasped with the hand of a master. The sketch
in the letter hastily made forty years ago is more ingenious than any
portable engine since constructed, though there may be no sufficient
proof of its practical success. The propeller to be worked by this
novel engine was of course his long-idle screw.

 _Steam Engines, 21st February, 1831._

 "NOW KNOW YE, that in compliance with the said proviso, I,
 the said Richard Trevithick, do declare that the essential points in
 my improved steam-engine, for which I claim to be the first and true
 inventor, are:--

 "Firstly, the placing of the boiler within the condenser, in order to
 obtain the additional security of the strength of the condenser to
 prevent mischief in case the boiler should burst, and also by the same
 arrangement to conveniently make the condenser, with a very extensive
 surface, enabling me to condense the steam without injecting water
 into it.

 "Secondly, the enclosing of the condenser in an air or water
 vessel, by which the intention of safety from explosion is further
 provided for, and my engine really rendered what I denominate it, a
 high-pressure safety engine.

 "Thirdly, the condensing of the steam in the condenser by means of a
 current of cold air or cold water forced against the outsides of the
 condenser.

 "Fourthly, the returning of the condensed steam from the condenser
 back again into the boiler, to the end that sediment and concretion in
 the boiler may be prevented; and,

 "Fifthly, the blowing of the fire with the air after it has been
 heated by condensing the steam.

 "In forming my improved steam-engine I employ several or all of
 these points according to convenience, in combination with the other
 necessary parts of steam-engines in common use.

 "These, my essential points, will admit of various modifications as
 to form and proportions such as must be and are quite familiar to
 every competent steam-engine manufacturer, and therefore it will be
 sufficient for the perfect description of my improved steam-engine
 that I explain some of the modes of forming and combining the
 essential points of my invention with the other parts of steam-engines
 in common use. In my most favourite form of engine in which I condense
 by a current of cold air, the fire-place and flue, the boiler, the
 condenser, and the air-vessel, are made of six concentric tubes,
 standing in an upright position. The inner or first tube forms the
 fire-place and flue, and at the same time the inner side of the
 boiler. This tube is conical, having its small end upwards. The next
 or second tube is cylindrical, about 6 inches larger in diameter
 than the lower end of the first tube, and forms the outside of the
 boiler, leaving a space all round of about 3 inches at the bottom, and
 so much more at the top, as the flue is taper for holding water and
 steam between the two tubes. The third tube is about 2 inches larger
 in diameter than the second, in order to allow a space of about an
 inch for powdered charcoal or some other slow conductor of heat. This
 tube also constitutes the inner side of the air-vessel. The fourth
 tube is about 2 inches larger than the third, and forms the inner
 side of the condenser. The fifth tube, about 2 inches larger than the
 fourth, forms the outside of the condenser; and the sixth tube, about
 2 inches larger than the fifth, forms the outside of the air-vessel,
 and at the same time the outside of the whole of the generating
 and condensing apparatus, consisting of fire-place, flue, boiler,
 condenser, and air-vessel. These tubes are made of wrought-iron plates
 riveted together, and are all cylindrical, except the first, which
 is conical, the bottom or fire end being the largest. The first or
 inner tube is closed at bottom, but has an opening on one side near
 the bottom, through which the fire-bars are introduced, and the ashes
 and clinkers taken away. To this opening a neck-piece about 3 inches
 long is riveted, having a flange to fit against the inside of the
 second tube, when the two tubes are concentric, through, the side of
 which second tube is an opening corresponding with that in the first
 tube, and the flanch is screwed to the second tube so as to make one
 opening through the sides of the two tubes. The second tube extends
 downwards about 5 inches below the first tube, and has a flanch
 turning inwards, to which a second round plate of iron is screwed,
 forming the bottom of the boiler. The first tube has an external
 flanch at the top, and the second tube an internal flanch, both of the
 same height, and screwed to a cast-iron circular plate or cap-piece,
 which extends wide enough around the boiler to form also the cover
 for the air-vessel. This plate has a hole in the middle as large as
 the flue. The sides of the condenser and air-vessel are formed of
 four concentric tubes, each about 2 inches larger than the one within
 it. The inner and outer of these tubes constitute the sides of the
 air-vessel, and are each furnished with an external flanch at the
 top by which they are screwed to the cap-piece. The two intermediate
 tubes constituting the sides of the condenser are riveted together at
 the top, leaving a space of about an inch between their upper ends
 and the cap-piece, so as to allow of a free communication over them
 between the outer and inner parts of the air-vessel. The inner tube of
 the air-vessel extends downwards about an inch below the boiler, and
 is closed by a flat plate screwed on to a flanch projecting inwards
 from the tube; the two tubes of the condenser descend about 3 inches
 lower than the boiler. The inner tube has an internal flanch, to which
 a flat circular plate is screwed to close up the tube. The outer
 tube of the condenser is of the same length with the inner, and is
 provided with an external flanch about 3 inches broad. The outer tube
 of the air-vessel has an external flanch 2 inches broad, and is just
 long enough to come down upon the broad flanch of the condenser last
 described, and these two flanches are together bolted upon a bottom
 piece of cast iron, which is a dish of 4 inches deep, and equal in
 diameter with the diameter of the outer tube, and having a flanch the
 same breadth as the flanch of the outer tube, and the bottom piece is
 secured to the air-vessel and outer tube of the condenser by bolts
 going through all the three flanches. An opening is made through the
 sides of all the four tubes of the condenser and air-vessel opposite
 to and as wide as the fire-place opening through the sides of the
 boiler. The upper part of both openings to be of the same height,
 but the outer opening is made as low as the bottom of the boiler, in
 order to allow room for a pipe to enter that part of the boiler for
 forcing the water into it, and also another pipe and cock for drawing
 off the water or sediment, in case foul water be used by accident or
 carelessness. These two openings through the condenser and air-vessel,
 and through the boiler, constitute one fire doorway through all the
 six tubes for access to the fire-place; a ring is placed between the
 two tubes of the condenser around the fire doorway, so as to cut off
 all communication of the steam in the condenser with the air in the
 doorway; another similar ring is placed between the condenser and the
 outer tube to prevent the escape of air into the fire doorway, and
 a half ring is placed in the lower part of the fire doorway between
 the condenser and the inner tube of the air-vessel, to prevent ashes
 from falling into the air-vessel, and yet allow a free passage for
 the air from the inner part of the air-vessel into the upper part of
 the fire doorway. These two rings and the half ring are secured in
 their places by rivets passing through all of them and through the
 tubes, and uniting all firmly together, the interstices being filled
 with iron cement. A ring is also placed between the boiler and the
 air-vessel around the fire doorway, against the outside of which ring
 the charcoal powder is tightly rammed, and will hold the ring in its
 place without the necessity of either rivets or screws. That part
 of the fire doorway which is above the fire-bars is supplied with
 an inner door, to shut the fire-place even with the outside of the
 boiler, and exclude all access of air to the fire, except through the
 grating. The whole of the fire doorway is enclosed by an outer door
 even with the outside of the air-vessel, to exclude all air, except
 that which comes through the air-vessel; a pipe is fixed in the bottom
 or dish-piece leading to a forcing pump to draw the water out of the
 condenser and force it into the bottom of the boiler through the pipe
 before described. A blowing cylinder of about ten times the content of
 the main cylinder is screwed against the outside of the air-vessel,
 and opposite to the two outlet valves of the blowing cylinder two
 apertures are made in the air-vessel, through which the air is
 forced in. The main cylinder of the engine, of the usual dimensions
 according to power wanted, is also screwed against the outside of the
 air-vessel high enough above the blowing cylinder to allow room for
 the main-crank shaft to work between them. The forcing pump before
 mentioned is also screwed to the outside of the air-vessel, and thus
 my improved steam-engine becomes more compact and convenient than any
 preceding steam-engine. For the purpose of supplying the boiler with
 distilled water, in case there should be a deficiency in it, a small
 vessel made of two upright tubes, one within the other, is placed on
 the cap-piece. The inner tube is of the same diameter as the flue, and
 forms a continuation of it. The outer tube is about 6 inches larger
 than the inner, and the space at the top and bottom between the two
 tubes is closed by two ring-shaped pieces. This vessel may be about
 18 inches high; a cock is fixed in the top of this vessel, to which
 a bent pipe is fastened, leading to and united with a pipe which
 arises from the top of the condenser and passes through a hole in the
 cap-piece, and thus a communication between the supplying vessel and
 the condenser may be opened or shut at pleasure; another pipe, also
 furnished with a stop-cock, arises from the vessel, and communicates
 with a water-cistern to receive its supply of water when required; a
 third pipe, having a cock in it, opens into the vessel near the bottom
 to let out the sediment; a small cock to let the air out is also fixed
 in the top of the vessel, which cock may also be used for letting air
 out of the condenser. In order to supply the boiler with water by
 means of this vessel, the stop-cock leading to the condenser is shut,
 and that leading to the cistern is opened, and at the same time the
 air-cock is opened to allow the air to escape that the water may fill
 the vessel. When the vessel is nearly full of water, the air-cock
 and the cock from the cistern are shut, and that in the pipe leading
 to the condenser is opened. The water being then heated by the flue
 is converted into steam, which, passing into the condenser, is there
 reduced to water again, leaving the sediment or salt in the supplying
 vessel, which sediment or salt may be occasionally blown out through
 the bottom pipe by filling the vessel with, water, shutting the water,
 steam, and air cocks, and opening the cock of the outlet pipe at a
 time when the steam in the vessel is strong. But the supply of water
 from the condenser being always equal to that converted into steam
 and used in the engine, there is no tendency to a variation in the
 height of the water in the boiler, except there be leakage or waste
 of steam in some part of the engine. An upright glass tube, having
 an iron tube of communication with the lower part of the boiler and
 another iron tube of communication to the upper part of the boiler, is
 conveniently placed against the outside of the air-vessel to indicate
 at all times the height of the water in the boiler; as is usual in
 steam-boilers, a valve is placed on the top of the air-vessel to
 allow of the escape of a portion of the air in case that the quality
 of the fuel should not require so much air for perfect combustion
 as the steam requires for good condensation. The degree of the
 condensation of the steam may be increased at pleasure, by increasing
 the velocity of the air passing into and through the air-vessel. The
 other parts of my improved steam-engine, such as the steam-pipes,
 the throttle-valve, the safety-valve, the vacuum-valve, the working
 valves, crank, connecting rods, cross-heads, pistons, piston-rods,
 and various other minor parts common to engines in general use may be
 made in the usual forms, and placed in the most convenient situations;
 they cannot, therefore, need any description. When it is intended to
 use water for condensing instead of air, my improved steam-engine must
 be made as before directed, except that the communication between
 the air-vessel and the fire-place must be closed, which may be done
 by a perfect ring of iron surrounding the opening leading to the
 fire-place, instead of the half ring before described, and a forcing
 pump must be employed to draw water from a reservoir, and force it
 into the vessel which I have hereinbefore denominated the air-vessel,
 but which in this mode of working would more properly bear the name
 of water-vessel. In this case a blowing cylinder, the dimensions of
 which must be calculated according to the quality of the fuel to be
 used, may be worked to blow the fire through a pipe leading into the
 ash-pit. This, however, will not be necessary where there is a chimney
 high enough to create a strong draught. In respect to proportions, my
 improved steam-engine admits of considerable latitude, and it will
 be sufficient direction to any practical engineer to say that for
 engines working with steam of 120 lbs. to the inch, used expansively
 till it be nearly reduced to atmospheric strength and then condensed,
 a 10-horse engine may have a fire-place of 20 inches diameter, the
 flue at the top 10 inches diameter, and a boiler of 20 feet high; a
 60-horse engine, a fire-place of 36 inches diameter, a flue of 16
 inches diameter, and a boiler of 20 feet high. In boat-engines, and
 in other cases where height cannot be allowed, the diameter must be
 increased. The thickness of the two tubes constituting the boiler
 sides of a 10-horse engine may be 1/8th of an inch, that of a 60-horse
 a quarter of an inch, and so in proportion for engines of other power.
 The tubes constituting the condenser and inner tube of the air-vessel
 may in all cases be 1/8th of an inch thick. The outer tube may be
 3/8ths of an inch thick, to afford stability to the working cylinder,
 the blowing cylinder, and the forcing pump fastened to this tube,
 and as an ultimate perfect barrier against explosion. The respective
 distances of the other tubes constituting the outside of the boiler,
 the condenser, and air-vessel, will be the same as hereinbefore given,
 and therefore their diameters will depend upon the diameter of the
 fire-place. The cap-piece in small engines may be half an inch thick,
 and in large engines an inch. The bottom of the ash-pit and bottom of
 the boiler must have about half an inch of thickness for every foot
 diameter, or they may be cast with ribs to afford equivalent strength.
 The fuel is supplied through a door in the flue, at the top of the
 boiler, consisting of coke or coals the least liable to swell with
 heat. The flue may be filled to about one-third of the height of the
 boiler, and the water fill about three-fourths of the boiler, leaving
 one-fourth for steam.

 "Having clearly explained my improved steam-engine so that any person
 competent to make a steam-engine can from this description understand
 my invention and carry the same into effect in as beneficial a manner
 as myself, I proceed to observe that the extreme safety of my
 improved steam-engine will be seen, from considering that in case the
 boiler should explode inwards into the flue, the power of the steam
 would be first reduced by filling the flue and fire-place, and could
 not escape through the chimney and fire doorway faster than it would
 diffuse itself and be condensed by mixing with the surrounding air,
 and thus lose all its force. But should the outside of the boiler
 burst, part of the force of the steam would be spent in filling up
 the interstices between the particles of the charcoal, and would then
 probably be too weak to effect a breach through the inner tube of the
 air-vessel; and should such a second breach be effected, the space
 within the air-vessel would allow the steam to expand and partly
 condense, and a portion to escape into and through the fire doorway,
 where it would divide itself, and proceed harmlessly up the flue,
 and out at the doorway; so that the outer case being a reserve of
 strength, would to a certainty withstand the force remaining in the
 steam after the before-mentioned successive reductions of power."

The patent of February, 1831, perfects the sketch in his letter of
July 27th, 1829, which in its turn made more perfect the plans put
into practice in 1815, just before leaving England for America.[175] The
prejudice against the use of his high-pressure steam-engine he tried
to meet by calling it "a high-pressure safety engine." The boiler was
of six wrought-iron upright tubes, one within the other. The inner one
was the fire-tube, surrounded by a tube of larger diameter, forming
the water and steam space. This was again surrounded by another tube,
2 inches larger in diameter, the space being filled with charcoal or
other non-conductor of heat; another tube, 2 inches more in diameter,
formed the inner circle of the condenser, having an inch space for
the passage of cold air from the blowing cylinder, carrying the heat
from the condensing steam back to the fire-place. Still another tube,
2 inches more in diameter, giving a space into which the used steam
from the cylinder passed to be condensed. Then came the outside tube,
2 inches more in diameter, forming a second space for the passage of
air, taking heat from the condenser into the fire. The steam-boiler had
its heat retained by a coating of charcoal; next to it came a current
of cold air an inch thick, carrying back to the fire any heat that had
passed through the charcoal coat, and also the heat from the inner
surface of the condenser. Then came the inch-thick circle of steam, on
its exit from the cylinder, to be condensed; and finally an outside
circle of cold air, performing the same functions as the inner circle
in condensing the steam and carrying its heat back again to the fire.

[Footnote 175: See Trevithick's letters, July 8th, 1815, vol. ii., p. 80,
and 7th, vol. i., p. 364; and 16th May, vol. i., p. 370; and patent of
1815, vol. i., p. 375.]

The object or principle of this engine was to avoid the loss of
heat, and the necessity for either condensing water or feed-water,
as described in the letter and drawing of August 19th, 1830, but the
detail was changed, mainly to facilitate construction. As in practice
it might be impossible to fully attain those objects, preparation was
made to get rid of the salt from such water as might be required as
feed-water to make good the loss from leakage or other defects in the
working of marine steam-engines. The specification states: "For the
purpose of supplying the boiler with distilled water, in case there
should be a deficiency in it, a small vessel made of two upright tubes,
one within the other, is placed on the cap-piece. The inner tube is
of the same diameter as the flue, and forms a continuation of it. The
water being heated by the flue is converted into steam, which, passing
into the condenser, is there reduced to water again, leaving the
sediment or salt in the supplying vessel."

Where water condensation was preferred the surface-air condenser could
be converted into a surface-water condenser by a current of cold water
in place of the air; in which case the air from the blowing cylinder
was taken direct in to the fire-place or other means used for giving
the necessary draught. Steam of about 135 lbs. to the inch was to be so
expansively worked as at the finish of the stroke, on its escape to the
condenser, to be no more than atmospheric pressure, or 15 lbs. to the
inch--just the strength with which Watt preferred to commence his work
in the cylinder.

The most prominent feature in Trevithick's numerous modifications of
the steam-engine was the boiler. In the 'Life of Watt,' though his
commentators have been numerous and eminent, little or nothing is said
about the boiler or the steam pressure. He left that all-important
part of the steam-engine just as he found it, resisting the increase
of steam pressure, which was the mainspring of Trevithick's engine.
The boiler of the high-pressure engines of 1796[176] sheltered the
steam-cylinder from cold; and the used steam from the cylinder
circulated around the exterior of the boiler, on its way to the
blast-pipe, while the condensed portion was returned as feed-water
in the patent engine of 1802.[177] In 1811 he proposed to force air
into the fire-place, hoping thereby to reduce the amount of heat lost
by the chimney.[178] His various forms of tubular boilers, as at the
Herland Mine,[179] and at Dolcoath,[180] and the upright multitubular
boilers patented in 1815.[181] followed up in 1828. "I shall have a small
portable engine finished here next week, and will try to heat steam
independent of water, in small tubes of iron, on its passage from the
boiler to the cylinder, and also try cold sides for condensing." In
1829 a simple boiler and condenser composed of three tubes was made,
the inner or fire-tube being 2 feet in diameter and 15 feet long, "for
the express purpose of experimenting on the working the same steam and
water over and over again;"[182] and on the same subject, "By making the
condenser of 4-inch copper tubes 1/32nd of an inch thick, it would
stand in one-twentieth part of the space of the boiler:"[183] and finally
the sketch of the tubular boiler and tubular condenser of 1830, in its
boiler portion similar to the best portable boilers of the present day,
and the patent specification of 1831. Surely therefore to him belongs
the credit of having invented and perfected the tubular boiler and
surface condenser.

[Footnote 176: See vol. i., p. 104.]

[Footnote 177: See patent specification, vol. i., p. 128.]

[Footnote 178: See Trevithick's letter, 13th Jan., 1811, vol. ii., p. 6.]

[Footnote 179: See vol. ii., p. 71.]

[Footnote 180: See chap. xx.]

[Footnote 181: See Trevithick's letters, 8th July, 1815, vol. ii., p. 80;
and 7th and 16th May, vol. i., pp. 364, 370.]

[Footnote 182: See vol. ii., p. 332.]

[Footnote 183: See vol. ii., p. 336.]

Smiles has written:[184]--

[Footnote 184: See 'Life of George Stephenson,' by Smiles, p. 279;
published 1857.]

 "For many years previous to this period (1829), ingenious mechanics
 had been engaged in attempting to solve the problem of the best and
 most economical boiler for the production of high-pressure steam.
 Various improvements had been suggested and made in the Trevithick
 boiler, as it was called, from the supposition that Mr. Trevithick
 was its inventor. But Mr. Oliver Evans, of Pennsylvania, many years
 before employed the same kind of boiler, and as he did not claim the
 invention, the probability is that it was in use before his time. The
 boiler in question was provided with an internal flue, through which
 the heated air and flames passed, after traversing the length of the
 under side of the boiler, before entering the chimney.

 "This was the form of boiler adopted by Mr. Stephenson in his
 Killingworth engine, to which he added the steam-blast with such
 effect. We cannot do better than here quote the words of Mr. Robert
 Stephenson on the construction of the 'Rocket' engine:--'After the
 opening of the Stockton and Darlington, and before that of the
 Liverpool and Manchester Railway, my father directed his attention to
 various methods of increasing the evaporative power of the boiler of
 the locomotive engine. Amongst other attempts, he introduced tubes
 (as had before been done in other engines)--small tubes containing
 water, by which the heating surface was materially increased. Two
 engines with such tubes were constructed for the St. Etienne Railway,
 in France, which was in progress of construction in the year 1828;
 but the expedient was not successful; the tubes became furred with
 deposit, and burned out.

 "'Other engines, with boilers of a variety of construction, were
 made, all having in view the increase of the heating surface, as it
 then became obvious to my father that the speed of the engine could
 not be increased without increasing the evaporative power of the
 boiler. Increase of surface was in some cases obtained by inserting
 two tubes, each containing a separate fire, into the boiler; in
 other cases the same result was obtained by returning the same tube
 through the boiler; but it was not until he was engaged in making
 some experiments, during the progress of the Liverpool and Manchester
 Railway, in conjunction with Mr. Henry Booth, the well-known
 secretary of the company, that any decided movement in this direction
 was effected, and that the present multitubular boiler assumed a
 practicable shape. It was in conjunction with Mr. Booth that my father
 constructed the 'Rocket' engine.

 "'In this instance, as in every other important step in science or
 art, various claimants have arisen for the merit of having suggested
 the multitubular boiler as a means of obtaining the necessary heating
 surface. Whatever may be the value of their respective claims, the
 public, useful, and extensive application of the invention must
 certainly date from the experiments made at Rainhill. M. Seguin, for
 whom engines had been made by my father some few years previously,
 states that he patented a similar multitubular boiler in France
 several years before. A still prior claim is made by Mr. Stevens, of
 New York, who was all but a rival to Mr. Fulton in the introduction of
 steamboats on the American rivers. It is stated that as early as 1807
 he used the multitubular boiler.

 "'These claimants may all be entitled to great and independent merit;
 but certain it is, that the perfect establishment of the success of
 the multitubular boiler is more immediately due to the suggestion of
 Mr. Henry Booth, and to my father's practical knowledge in carrying it
 out.'

 "We may here briefly state that the boiler of the 'Rocket' was
 cylindrical, with flat ends, 6 feet in length, and 3 feet 4 inches in
 diameter. The upper half of the boiler was used as a reservoir for
 the steam, the lower half being filled with water. Through the lower
 part twenty-five copper tubes of 3 inches diameter extended, which
 were open to the fire-box at one end and to the chimney at the other.
 The fire-box, or furnace, 2 feet wide and 3 feet high, was attached
 immediately behind the boiler, and was also surrounded with water."

Stephenson knew of Trevithick's patent of 1802,[185] in which a
three-tubed boiler is shown; and it was after that time that Oliver
Evans and Fulton tried their experiments, and also the numerous engines
with single or return double tube, at work in the principal towns of
England prior to 1804,[186] and near his residence in childhood and in
manhood.[187]

[Footnote 185: See vol. i., p. 128.]

[Footnote 186: See Trevithick's letter, Sept. 23rd, 1804, vol. ii., p. 2.]

[Footnote 187: Mr. Armstrong's note, vol. i., p. 184.]

George Stephenson's Killingworth boiler, "to which he added the
steam-blast with such effect," was a copy of Trevithick's boiler and
blast, working since 1804 in Newcastle-on-Tyne, and was precisely the
boiler described by Stephenson; "in other cases the same result was
obtained by returning the same tube through the boiler." This is an
admission from Stephenson that Trevithick's patent boiler was the best
in use up to about 1828.

A further proof of the indirect public gain from the use of
Trevithick's return-tube boiler over a period of thirty years is their
having supplied high-pressure expansive steam in the first experiments
made with such steam by the Admiralty, at whose request Mr. Rennie
and others examined the duty of the Cornish high-pressure expansive
engine, and Captain King, R.N., in charge of the Admiralty Department
at Falmouth in 1830, gave an order to Harvey and Co. to construct
high-pressure steam-boilers for the Government vessel 'Echo'; in 1831
the machinery was put on board the 'Echo' in the Government Dockyard
at Plymouth, and included three of Trevithick's return-tube boilers,
made of wrought iron, each 5 feet 6 inches in diameter and 24 feet
long, with internal return fire-tube 2 feet 2 inches in diameter. The
fire-place end of the boiler was 6 feet 9 inches deep by 5 feet 6
inches wide, to give room for the fire-place and ash-pit. The steam
pressure was 20 lbs. on the inch above the atmosphere, worked by
double-beat valves, 6 inches in diameter, with expansive gear.

This new machinery was fixed under the superintendence of the writer,
after which the Government engineers took charge of the vessel, and
the writer who had, as the mechanic in charge, worked like a slave,
though receiving but 1_s._ 6_d._ a day and expenses, was not invited to
take any part in the experimental trials, nor ever heard of the result
except in the ordinary rumours of Admiralty bungling on board the
'Echo.'

Those boilers were similar to the Trevithick boiler that had served
the locomotive in Newcastle and elsewhere from 1801 to 1828, the first
steamboat experiments in England, in Scotland, and in America, and the
numerous high-pressure engines then at work.

[Illustration: BOTTLE-NECK BOILER.]

The enlarging the fire-place end of boilers or fire-tubes has led
to many forms. Trevithick's model of 1796[188] had an oval tube
giving a greater spread of fire-*bars; the same is seen in the 1808
steamboat;[189] the Dolcoath boilers of 1811[190] show the oval and also
the bottle-neck fire-tube; the Welsh locomotive of 1804[191] had the
fire-tube contracted at its bend or return portion; the Tredegar
puddling-mill fire-tube of 1801[192] tapered gradually from the
fire-bridge to the chimney end; in the London locomotive of 1808[193]
the fire-tube took the bottle-neck shape close to the fire-bridge. The
accompanying sketch shows the bottle-neck contraction, only on the
top and sides of the fire-tube was to give breadth to the fire-bars
_d_, and thickness to the fire at bridge _c_, after which the flue
portion of the fire-tube was contracted: this boiler was for many
years a favourite in Cornwall. The bottle-neck contraction of the
'Echo' boiler was similar to the above, except that the enlargement of
the fire-place was downwards instead of upwards, and the fire-tube,
instead of going through the end of the boiler, returned to near the
enlarged fire-place, when it passed out through the side of the boiler
to the chimney, just as in the Tredegar puddling-mill boiler; all those
variations were with the object of increasing the fire-grate, and at
the same time keeping down the gross size and weight of boiler and its
water.

[Footnote 188: See vol. i., p. 104.]

[Footnote 189: See vol. i., p. 335.]

[Footnote 190: See vol. ii., p. 169.]

[Footnote 191: See vol. i., p. 181.]

[Footnote 192: See vol. i., p. 223.]

[Footnote 193: See vol. i., p. 207.]

In 1805, Lord Melville failed to keep his appointment with Trevithick,
on his proposal to construct a high-pressure steamboat.[194] Rennie, a
pupil and friend of Watt, and familiar with Trevithick's high-pressure
steam-dredgers on the Thames, was employed by Lord Melville and the
Admiralty on the Plymouth Breakwater, where in 1813 Trevithick proposed
the use of his high-pressure steam locomotive and boring engine.[195]
In 1820 Rennie wrote to Watt, that the Admiralty had at last decided
upon having a steamer; at that time fifteen years had passed since
Trevithick's offer to propel the Admiralty by steam-puffers, and ten
years more were to pass before they could make up their minds to
venture on high-pressure steam from his boilers. The Steam Users'
Association are equally hesitating, judging from words just spoken by
an engineer, the son of an engineer:--

[Footnote 194: See Trevithick's letter, 10th Jan., 1805, vol. i., p. 324.]

[Footnote 195: Ibid., vol. ii., p. 24.]

 "Sir William Fairbairn said he had come to the conclusion, after
 many years' experience, that it was in their power to economize the
 present expenditure of fuel by a system which might not be altogether
 in accordance with the views of the members of the association or
 the public at large, and that was to increase the pressure of steam.
 He would have great pleasure in stating a few facts which might some
 day tend to bring about a change, if not a new era, in the use of
 steam. From the result of a series of experimental researches in which
 he had been engaged for several years on the density, force, and
 temperature of steam, he had become convinced that in case we were
 ever to attain a large economy of fuel in the use of steam, it must
 be at greatly-increased pressure, and at a rate of expansion greatly
 enlarged from what it was at present. Already steam users had effected
 a saving of one-half the coal consumed by raising the pressure from
 7 lbs. and 10 lbs.--the pressure at which engines were worked forty
 years ago--to 50 lbs., or in some cases as high as 70 lbs. on the
 square inch."[196]

[Footnote 196: 'The Engineer,' March 15th, 1872: remarks by the Chairman
at a meeting of the Manchester Steam Users' Association.]

Dear me! would have been Trevithick's exclamation had he read this;
did I devote my whole life to the making known the advantages of
high-pressure steam, and did I, seventy years ago,[197] really work
expansive steam of 145 lbs. on the inch in the presence of many of the
leading engineers of the day! Of course this short extract of a speech
made by a member of a practical society, may not be taken as conveying
fully the speaker's views, but it illustrates the immense difficulty
Trevithick encountered in making his numerous plans acceptable to the
public.

[Footnote 197: See Trevithick's letter, August 20th, 1802, vol. i., p.
154.]

Another modern statement bearing on inventions originating with
Trevithick, but wearing new garbs with new names, shows the same
tendency to ignore old friends, or, to say the least of it, to pass
them by:--

 "The trial of No. 36 steam-pinnace was made at Portsmouth yesterday.
 Her peculiarity consists in the arrangement of her propelling
 machinery, in the adaptation of the outside surface condenser, and
 a vertical boiler, both patented by Mr. Alexander Crichton. The
 condenser is simply a copper pipe passing out from the boat on one
 quarter at the garboard strake, and along the side of the keel,
 returning along the keel on the opposite side, and re-entering the
 boat on that quarter. The boiler is designed for boats fitted with
 condensing engines, and which, therefore, are without the acceleration
 of draught given by the exhausted steam being discharged into the
 funnel. It is of the vertical kind, and stands on a shallow square
 tank, which forms the hot well. The tubes are horizontal over
 the fire, the water circulating through them. The condensed steam
 is pumped into the well at a temperature of 100°, and being there
 subjected to the heat radiating from the furnace, is pumped back into
 the boilers at nearly boiling point. It is estimated that, under these
 conditions, the pinnace would run for nearly 48 hours without having
 to 'blow off' or carry a supply of fresh water, the waste water being
 made good by sea water."[198]

[Footnote 198: 'The Times,' November 24th, 1871.]

The peculiarity of this steam-pinnace of 1871, on which a patent was
granted, is stated to be a metal surface condenser exposed to the cold
water at the bottom of the boat, returning the condensed steam at
about boiling temperature to the boiler, and a vertical boiler with
horizontal tubes through which the water circulates, both of which
in principle, if not in detail, are seen in the surface condenser of
Trevithick's iron-bottom ship of 1809, and his vertical boiler of
1816,[199] and further illustrated in the inventions spoken of in this
and the following chapter; and yet on so all-important a subject, dealt
with in various ways by Trevithick from 1804 to 1832, his plans are
reproduced as discoveries in 1871.

[Footnote 199: See vol. i., pp. 336, 364, 370.]

About 1828, Mr. Rennie, Mr. Henwood, and others, reported on the
advantages of high-pressure expansive steam in Wheal Towan engine,[200]
on the north cliffs of Cornwall, near Wheal Seal-hole Mine on St. Agnes
Head, where in 1797 Trevithick had worked his first high-pressure
steam-puffer engine in competition with the Watt low-pressure
steam-vacuum engine. Captain Andrew Vivian was then his companion, and
the Cow and Calf, two rocks of unequal size, a mile from the land, were
from that time called Captain Dick and Captain Andrew, or the Man and
his Man, and there they still remain in the Atlantic waves, fit emblems
of their namesakes and their still living inventions. The stir made by
those expansive trials led to the experiment in the 'Echo,' of which
Mr. Henwood[201] thus speaks:--

[Footnote 200: See Mr. Henwood's report, vol. ii., p. 185.]

[Footnote 201: Residing at Penzance, 1871.]

 "Captain William King, R.N., Superintendent of the Packet Station
 at Falmouth, attempted to impress on Viscount Melville, then First
 Lord of the Admiralty, the advantage of using high-pressure steam
 expansively in the Royal Navy, to whom Lord Melville replied that
 he had been taught by his friend, the late Mr. Rennie, that the
 danger attending such a course was very great, and that it would be
 difficult, if not impossible, to persuade him to the contrary."

[Illustration: CAPTAIN DICK AND CAPTAIN ANDREW, OR THE MAN AND HIS
MAN. [W. J. Welch.]]

Twenty-five years of precept and example caused the Admiralty to follow
suit, and to request Mr. Ward, a Cornish engineer, to construct boilers
and expansive valves for the Government steamboat 'Echo.' The writer
was entrusted with fixing the machinery in the vessel at the Plymouth
Dockyard, and before starting with it from Harvey and Co.'s foundry,
waited on Captain King, R.N., at Falmouth, for his instructions, in
happy ignorance of the fear of the Lords of the Admiralty to tread on
Cornish high-pressure. After eying the applicant as captains in Her
Majesty's service are apt to do when dealing with boys in the civil
service, he vouchsafed to say, "Mind, young man, what you are about,
for if there is a blow up, by ---- you'll swing at the yard-arm."




CHAPTER XXVII.

HEATING APPARATUS--MARINE STEAM-ENGINES--REFORM COLUMN.


  "LAUDERDALE HOUSE, HIGHGATE,

  "MR. GILBERT,          "_March 1st, 1830_.

 "Sir,--I have to apologize for my neglect in not calling on you, but
 ill-health prevented it. I left home on the 11th February, arrived
 in town on the 14th, and remained there until the 24th, when I was
 compelled to leave for this place, having a free good air. I am now
 taking, twice a day, the flowers of zinc, from which I hope to be soon
 right again. I am much better, but afraid to enter the city. I hope
 to be able to call on you before the end of this week, being very
 anxious to see you, having a great deal to communicate respecting the
 experiments I have been making, which will bear out to the full our
 expectations.

 "Your hot-house apparatus has been finished nearly three months, all
 but two or three days' work to fit the parts together; I expect that
 before this they are in Penzance, waiting a ship for London. While
 making a sketch of your work for the founder, a thought struck me
 that rooms might be better heated by hot water than by either steam
 or fire, and I send to you my thoughts on it, with a sketch for
 your consideration. I find that steam-pipes applied to heat cotton
 factories, with 1 surface foot of steam-pipe, heat 200 cubic feet of
 space to 60 degrees. I also found in Germany, where all the rooms are
 heated by cast-iron pipes about the heat of steam, that 1 foot of
 external flue heated 160 cubic feet of space to 70 degrees.

 "I find also that about 200 surface feet of steam-engine cylinder-case
 will condense about as much steam as will produce 15 gallons of water
 per hour, and will consume about 4 bushels in twenty-four hours to
 keep the temperature of 212 degrees. One bushel of coal will raise
 the temperature of 3600 lbs. of water from 40 to 212 degrees.

 "A boiler, as the drawing, will contain 1200 lbs. of water, and
 consume one-third of a bushel of coal to raise the water from 40 to
 212 degrees. It has 40 surface feet of hot sides giving out its heat.
 The 12-inch fire-tube in the boiler would raise the temperature to
 212 degrees in about forty minutes. By these proofs it appears that
 50 feet of surface steam sides will require 1 bushel of coal every
 twenty-four hours to keep up the boiling heat; therefore this boiler,
 having 40 surface feet, would give out the heat from one-third of a
 bushel of coal in twelve hours.

 "Now suppose this charge of heat required to be thrown off in either
 more or less than twelve hours, the circular curtain would adjust the
 heat and time for extracting it.

 [Illustration: HOT-WATER ROOM-WARMER.]

 "By the foregoing this coal and surface sides would heat to 60 degrees
 for twelve hours a space of 6800 cubic feet, equal to a room of 25
 feet square and 11 feet high. If this boiler was placed in a room
 with a chimney, its water could be heated by having a small shifting
 wrought-iron chimney-tube of 4 inches diameter and 2 or 3 feet long
 attached to the end of the boiler while it was getting up steam, after
 which it might be removed, and the doors at both ends of the boiler
 closed; and as the boiler contains and retains its heat for twelve
 hours, more or less, it might be run on its wheels to any fire-place
 or chimney to get charged with heat, and then run into any room, where
 there was no chimney, or into bed-rooms, offices, or public buildings;
 it would be free from risk, not having either steam or loose fire.
 The circular curtain, being fast to a wood table, would by being
 drawn up or down adjust the required heat and hide the boiler, and
 would be warm and comfortable to sit at. I think this plan would save
 three-quarters of the coal at present consumed; the expense of the
 boiler will not exceed 5l. When you have taken it into consideration,
 please to write me your opinion.

  "I remain, Sir,
  "Your very humble servant,
  "RD. TREVITHICK.

 "P.S.--Boiler, 3 feet diameter, 3 feet long; fire-tube, 12 inches
 diameter, placed in the boiler, the same as my old boilers, made of
 iron plates 1/8th of an inch thick, weighing about 2 cwt.

 "I had a summons to attend at Guildhall last Saturday on the coal
 trade, and was requested to attend a committee at Westminster for the
 same purpose, in consequence of my applying small engines to discharge
 ships.

 "I attended, but with difficulty, from my ill-health."

Trevithick was not above scheming for his friend's hot-house, warming
it by a boiler on wheels, in form like his high-pressure steam-boiler.
Rooms had before been heated by steam or hot air in pipes; but he
thought a more simple and economical plan was to heat a certain
quantity of water to boiling heat at any convenient place having a
chimney, or in the open air, and then wheel the apparatus into the room
to be warmed. If the room had a chimney, the fire could be kept up,
or the temporary iron connecting chimney be removed and the apparatus
wheeled into the middle of the room and used as a table.

The scheme promised to be successful, for in a letter nine months
after the former he wrote that he had taken a patent for France, where
it had made a great bustle among the scientific class, for coal in
Paris was 3_s._ a hundredweight; some hot-water room-heaters were the
following day to be forwarded from London to Paris; while the numerous
orders were more than he could execute. One in use at the 'George and
Vulture' Tavern, of a Gothic shape, handsomely ornamented with brass,
about two-thirds the size of the one in Mr. Gilbert's hot-house, burns
7 lbs. of coal a day, keeping the room at 65 degrees of heat during
fifteen hours. The rage amongst the ladies was to have them handsomely
ornamented.

Believing that they would be remunerative, he applied for the following
English patent in February, 1831.


[Illustration: PLATE 16.

HEATING APPARATUS.

  London: E & F.N. Spon, 48. Charing Gross. Kell Bros. Lith. London.]

 _Apparatus for Heating Apartments. 21st February, 1831._

 "NOW KNOW YE, that in compliance with the said proviso, I,
 the said Richard Trevithick, do hereby declare that the nature of
 my said invention of a method or apparatus for heating apartments,
 and the manner in which the same is to be carried into effect, is
 shown by the following drawings and description, where Fig. 1, Plate
 XVI., represents a longitudinal vertical section through the middle
 of a metallic vessel capable of containing a considerable quantity
 of water, with a fire-place in the inside, surrounded with water in
 all parts except at the doorway and at an opening where the smoke
 may pass off into a common chimney. Fig. 2, a vertical section near
 the fire-door, at right angles to the section shown at Fig. 1; with
 the sections are also shown wheels and handles, which lie out of the
 planes of the sections. The letters of reference indicate the same
 parts in both figures, _a_, the vessel; _b_, the space for containing
 the water; _c_, the fire-place; _d_, the fire-bars, or grating; _e_,
 the ash-pit; _f_, an inner door, to prevent the air from entering
 over the fire, yet allow it to pass into the ash-pit, and thence up
 to the fire through the grating; _g_, an outer door, to be shut when
 the fire is to be extinguished; _h_, a chimney or flue, to convey the
 smoke into a common chimney: this flue may be removed when the water
 boils, and then the opening of the flue may be shut, to keep in the
 heat, either by a door or by a plug fitting the opening; _k_, the
 cover of the vessel, having a rim all round, within which iron cement
 is to be driven to make the vessel steam-tight; _l_, a hole in the
 middle of the cover, into which a plug is dropped having a fluted
 stem and a flat head ground steam-tight upon the cover; this plug or
 valve is for the purpose of allowing the escape of steam if it should
 be raised above boiling point, and the valve is taken out when it
 may be necessary to pour water into the vessel; _m_, four wheels, on
 which the vessel may be easily removed from one room to another; _n_,
 two handles, to facilitate the removal. To use this apparatus for
 the warming of an apartment, the vessel is nearly filled with water,
 and placed so near to a chimney in another room, if more convenient,
 that the flue-piece _h_ may convey away the smoke; a fire is then
 lighted upon the grating _d_, and continued till the water boils,
 when the flue-piece is taken away, and the flue opening stopped with
 the plug or door, and also the outer fire-door closed. In this state
 the apparatus is drawn into the apartment to be warmed, where it will
 continue for many hours to give off a most agreeable heat without any
 of that offensive odour usually experienced from stoves heated by
 an enclosed fire. Figs. 3, 4, 5, and 6 represent another form of my
 apparatus for heating churches or other large buildings. Fig. 3, a
 vertical section, from A to B, of Figs. 5 and 6, with a representation
 of the flue and its flanch, which lie beyond that section and the fire
 doorway and its flanch, which lie nearer, and also the four wheels,
 two of which are on each side of the section. Fig. 5, a horizontal
 section, from E to F, of Figs. 3 and 4. Fig. 6, a horizontal section,
 from G to H, of Figs. 3 and 4, with a view of the four handles
 situated at a higher level than the section, and of the fire-bars at a
 lower level; the same letters of reference signify the same parts in
 all the four figures, _a_, the outer case of the water-vessel; _b_,
 the cover; _c_, the space for water; _d_, the fire-place and flue;
 _e_, the fire-bars, made in two pieces, to be introduced through the
 fire doorway; _f_, the ash-pit; _g_, the fire-door; _h_, pipes open at
 top and bottom, cemented into holes in the bottom, and in the cover of
 the water-vessel; these pipes are to admit a current of air up through
 them, in order the more speedily to carry the heat into the building;
 _k_, the aperture in the cover, to supply the vessel with water, and
 the plug to keep in the steam; _l_, four wheels, on which the whole
 is moved, each wheel revolving in a recess cast in the bottom of the
 outer case, as represented by dotted lines in Figs. 3 and 4; _m_,
 four handles; _n_, the flanches of the fire doorway and of the flue,
 represented in Fig. 4 by dotted lines. A pipe to communicate with a
 chimney while the water is being heated must be made to suit locality,
 and therefore cannot require any description. This apparatus can be
 heated in a vestry room, and the fire-door and flue closed and then
 wheeled into the church, where it will soon diffuse a most comfortable
 warmth; or the heat may be kept up while standing in its place by
 having a constant communication with a chimney, and thus diffuse a
 much more salubrious heat than can be obtained by metallic or earthen
 stoves heated immediately by the fire."

It is doubtful if the profits he received from the heating apparatus
covered the cost of the patent. The first stove was not unlike his
first locomotive boiler. The more highly-finished stove resembled the
marine tubular boiler, also of former years, in the further application
of which we now follow him.

  "MR. GILBERT,          "HAYLE, _January 24th, 1829_.

 "Sir,--Since I have been down I have made a small portable engine,
 and set it to work on board a coal-ship for discharging the cargo; it
 is very manageable, and discharges 100 tons with 1 bushel of coal,
 without any person to attend it, there being a string that the man in
 the hold draws when the coal-basket is hooked, which is again drawn
 by the man who lands the basket on the deck; the string turns and
 re-turns the engine. It is near a ton weight, but as I find it double
 the power required, I am now making a smaller one, 3-1/2 feet high and
 3-1/2 feet diameter, about 12 cwt.

 "I intend this engine to warp the ship, pump it, cook the victuals,
 take in and out the cargo, and do all the hard work. The captains are
 very anxious to get them on board every ship. I think that an engine
 of 39 cwt. would propel their ships four miles an hour over and above
 the other work of the ship, and would neither be so heavy or take so
 much room as their present cooking house and furnace. I think that
 two iron paddles, one on each side of the rudder, under the stern,
 would do this very well; they would be in dead water, and out of the
 swell of the sea, and by being deep in the water would have a good
 resistance. Two paddles, each about 4 feet deep and 3 feet wide, would
 do this, without their rising out of the water; therefore their stroke
 would be nearly horizontal. The return stroke would be in the water.
 Thus, let the paddle stand perpendicular in the water, two-fifths of
 its width on one side, and three-fifths on the other side, the centre,
 which would turn its edge to the water on its back stroke, and its
 flat to the water on the forward stroke; it would be light, and out
 of the way of anything. I have a patent now going through the office
 for all this, which will also cover the new principle of returning
 the heat back again, as already described to you. The engine for
 drawing in Holland will be ready about the end of February, and by
 that time I shall have a complete portable engine ready for London for
 discharging, when I shall be in town.

 [Illustration: BOAT AND PROPELLER.]

  "I remain, Sir,
  "Your very humble servant,
  "RD. TREVITHICK.

 "P.S.--Wheal Towan engine is working with three boilers, all of the
 same size, and the strong steam from the boilers to the cylinder-case;
 the boilers are so low as to admit the condensed water to run back
 from the case again into the boiler. They find that this water is
 sufficient to feed one of these boilers without any other feed-water;
 therefore one-third of the steam generated must be condensed by the
 cold sides of the cylinder-case, and this agrees with the experiments
 I sent to you from Binner Downs. Wheal Towan engine has an 80-inch
 cylinder, and requires 72 bushels of coal in twenty-four hours;
 therefore the cylinder-case must in condensing high-pressure steam
 use 24 bushels of coal in twenty-four hours. Boulton and Watt's case
 for a 63-inch cylinder, working with low-pressure steam, condensed
 only 4-1/2 bushels of coal in equal time, the proportions of surface
 being as 190 to 240 in Wheal Towan. Nearly five times the quantity was
 condensed of high steam than of low steam, proving that there is a
 theory yet unaccounted for."

Trevithick's portable high-pressure steam-puffer engine, when it
discharged the first cargo of coal from a vessel at Hayle, was worked
by the writer; it stood on the wharf near the ship, and on a signal
from the hold, steam was turned on, raising rapidly the basket of coal
the required height. In trying how quickly the work could be done
the hook missed the basket-rope, and caught the man under the chin,
swinging him high in the air, much to the engineman's discomfiture.
Fortunately the suspended man had the good sense to lay hold of the
rope above his head, and so supporting his weight, no great harm was
done.

The object and the means were the revival of the nautical labourer
of twenty years before.[202] The boiler was a wrought-iron barrel on
its end, on small wheels, with internal fire-tube, in shape like the
boiler of the recoil engine of 1815;[203] but less high in proportion to
its diameter. The cylinder was let down into the top of the boiler,
and like Newcomen's atmospheric engine had no cylinder cover. The
piston-rod was a rack giving motion to a small pinion fixed on a shaft
on the top of the boiler, and to a large grooved wheel, around which
was wound the whip-rope from the vessel's hold; a brake-lever enabled
the engineman either to stop or to reduce the speed. Four months prior
to the date of this letter he had sent a written offer to the Common
Council of the city of London, offering to provide engines to discharge
all coal-ships for the saving he would effect in six months, or he
would supply an engine and boxes complete for 100 guineas. He at the
same time suggested that in place of the baskets holding 1 bushel, iron
boxes on wheels, holding 4 bushels, with a spring steelyard attached,
should be used with his steam-engine, giving the exact weight without
delay. He seems to have forgotten his nautical labourer patented twenty
years before;[204] but yet reproduced something very similar.

[Footnote 202: See chapters xiv. and xv.]

[Footnote 203: See Trevithick's letter, 7th May, 1815, vol. i., p. 364.]

[Footnote 204: See vol. i., p. 325, and patent, 1809, vol. i., p. 302.]

Every trading vessel was recommended to carry at least a 12-cwt.
high-pressure steam-puffer engine, suitable for warping, pumping, and
discharging cargo; but a 30-cwt. engine, not occupying more room than a
caboose, would in addition cook for the crew, and propel the vessel at
three or four miles an hour.

Two iron paddles, like the duck's feet described to his Binner Downs
friends many years before,[205] were to be fixed on an iron shaft across
the stern of the vessel, receiving from the engine a motion like a
pendulum. Each duck's foot was an iron plate 4 feet deep and 3 feet
wide, turning partly round on its iron leg, to which it was attached as
a vane, about 1 foot of its width on one side of its leg, and 2 feet
on the other side; when the leg and foot were drawn toward the vessel,
the foot, turning on its leg as a centre, exposed its edge only to the
water; on the reverse movement, the longer side like a vane turned
round until its flat was opposed to the water, in which position it was
kept by a catch until the return movement, so that when it propelled,
its whole surface pressed against the water, and when moving in a
contrary sense, only its edge offered resistance to the water.

[Footnote 205: See Mr. Newton's letter, vol. i., p. 342.]

The writer has no record of the practical application of the duck's
foot as a steamboat propeller; but the portable puffer-engine now
pulls on board the fisherman's heavy nets, and the magnificent steamer
'Adriatic' hoists her sails on iron yards and masts by six of those
steam helps.[206]

[Footnote 206: See 'Illustrated News,' 27th April, 1872.]

Twenty years before he had solicited the Navy Board to try his iron
ships propelled by high-pressure steam-engines, and had shown their
applicability as steam-dredgers; and again, shortly after his return
from America, he pressed on their attention the same subject under new
forms, followed by communications with their engineer, Mr. Rennie, and
a proposal to place an engine in a boat at his own cost.

The writer has attempted in this and the preceding chapter to classify
Trevithick's schemes, crowded together in those last years of his life,
but the subjects so run into one another that the acts of twenty years
before must be borne in mind to enable the more modern plans to be
understood.

The letter introducing the surface condenser, in 1828, at the
commencement of the former chapter, was in a month followed by that
recommending a particular kind of paddle to be used as auxiliary
steam-power, and after six months of experiments, by the patent of
1831, and the following correspondence:--

  "MR. GILBERT, "LAUDERDALE HOUSE, HIGHGATE, _June 10th, 1830_.

 "Sir,--Yesterday I saw Mr. George Rennie, and he requested me to write
 to the Admiralty, a copy of which I send both to you and to him, for
 your inspection. Mr. Rennie said there was a great deal contained in
 what I had stated to him, and that he would with pleasure forward my
 views, as far as he could with consistency.

  "I remain, Sir,
  "Your very humble servant,
  "RICHARD TREVITHICK."

 "TO THE RIGHT HONOURABLE THE LORDS COMMISSIONERS OF THE
 ADMIRALTY, &c., &c., &c.

 "MY LORDS,

 "About one year since I had the honour of attending your honourable
 Board, with proposed plans for the improvement of steam navigation;
 and as you expressed a wish to see it accomplished, I immediately made
 an engine of considerable power, for the express purpose of proving by
 practice what I then advanced in theory. The result has fully answered
 my expectations; therefore I now make the following propositions to
 your honourable Board, that this entirely new principle and new mode
 may be fully demonstrated, on a sufficient scale for the use of the
 public.

 "I humbly request that your Lordships will grant me the loan of a
 vessel of about two or three hundred tons burthen, in which I will
 fix, at my own expense and risk, an engine of suitable power to propel
 the same at the speed required. No alteration in the vessel will be
 necessary, and the whole apparatus required to receive its propelling
 force from the water can be removed and again replaced with the same
 facility as the sails, thus leaving the ship without any apparatus
 beyond its sides when propelled by wind alone, and when propelled by
 steam alone the apparatus outside the ship will receive scarcely any
 shock from the sea.

 "This new invention entirely removes the great objection of feeding
 the boiler with salt and foul water, and not one-sixth part of the
 room for fuel, or of weight of machinery now used, will be required;
 it is also much more simple and safe, not only for navigation, but
 for all other purposes where locomotive power is required, and will
 supersede all animal power, as the objections of weight, room, and
 difficulty of getting and of carrying water in locomotive engines is
 entirely removed. It will therefore prove an investigation of greater
 utility to the public than anything yet introduced.

 "I have to beg the great favour of your Lordships appointing not only
 scientific but practical engineers to inspect my plans, that you may
 be perfectly satisfied of their utility, not only in theory, but also
 as to the practicability of carrying the same into full effect."

The petition in June, 1830, for the loan of a Government hulk, hung
fire up to January 1832, when an attempt was made to move the Lords
Commissioners of the Admiralty by the force of numbers.

 "We, whose names are hereunto subscribed, have known Mr. Richard
 Trevithick, of Hale, in the county of Cornwall, for a period of
 years, and during which time his conduct has merited our unqualified
 approbation. As an engineer of experience and eminence few, if any,
 can surpass him, and his present improvement of the steam-engine seems
 to outvie all others. We therefore, in justice to his talent, strongly
 recommend to the Lords Commissioners of the Admiralty that he may be
 permitted, at his own costs and charges, to fit and make trial of his
 engine in one of His Majesty's vessels.

 "Dated in London this 27th day of January, 1832."

This was sent to Mr. Davies Gilbert, who on the same date suggested the
following:--

 "RECOMMENDATION OF MR. RD. TREVITHICK, January 27, 1832.

 "We have not any doubt or hesitation in recommending Mr. Richard
 Trevithick as a man of extraordinary powers of mind, and of fertility
 of invention.

 "Cornwall owes to him much of the improvements that have been made on
 Mr. Watt's engine--improvements that have reduced the consumption of
 coal to a third; nor have his exertions been confined to steam-engines
 alone. He now proposes to make the same water act over and over again
 by alternate expansion and contraction, which plan, if it succeeds,
 will be found of immense importance to vessels and locomotive engines.

 "Understanding that Mr. Trevithick is desirous of making the
 experiment at his own expense, we clearly recommend that facilities
 may be afforded him."[207]

[Footnote 207: In the handwriting of Mr. Davies Gilbert.]

This paltry question with the Admiralty indirectly produced more
trustworthy evidence of the great importance of Trevithick's inventions
than all that has been written of him under the professional terms
Engineers, and Engineering.

The names are not given of those who believed that he had, as an
established fact, reduced the consumption of coal in the Watt engine to
one-third; they were not Cornishmen, or they would not have misspelt
the word Hayle, but they understood the great value of using the same
fresh water over and over again in marine steam-engines.

Mr. Mills, who had taken an active part in the screw-propeller
experiments in 1815, was again interested in the proposed trial in a
Government ship, and wrote, "I have just left Captain Johnstone; he
has communicated with Faucett and Co., Barnes and Miller, and with the
firm of Maudslay. He has had his mind disturbed again by Maudslay about
the greater quantity of water required to condense steam at higher
temperatures; I repeated the same as yourself, about the cylinder full
of steam, atmosphere strong; however, he appears quite different to
what he was on Friday." Such a clique of professional friends would
sink a stronger man than Trevithick. A year or two from that time the
writer designed a high-pressure steam-engine suitable for a steamboat,
and on presenting it to the eminent marine-engine builders whom he
served, was told that the lightness of the engine would cause less
profit to the makers. Their bills were based on the pounds weight
delivered, and new designs necessitated new patterns and new troubles.
It was unreasonable to expect those makers of marine steam-engines to
report that Trevithick knew better than they did. They knew of his
screw-propeller experiments fifteen years before, but they in no way
benefited him, and the Admiralty Captain was either a tool in their
hands, or powerless without them.

The primary object, when the loan of the ship was asked, was the using
for marine purposes a high-pressure steam tubular boiler, combined with
tubular condenser, supplying or returning its water as feed, thereby
avoiding the use of salt water in the boiler; and this steam-engine,
as shown in his patent of 1831, was to be applied either to his screw,
or his duck's foot, or other propeller; but during the year or two of
suspense, other schemes for propelling ships had occupied his thoughts,
resulting in the patent of 1832.

 _Steam-Engines, 1832._

 "NOW KNOW YE, that in compliance with the said proviso,
 I, the said Richard Trevithick, do hereby declare the nature of my
 said invention, as regards the improvement or improvements on the
 steam-engine, to consist in interposing between the boiler and the
 working cylinder, in a situation to be strongly heated, a long pipe
 formed of a compact series of curved or bent pipes, which I denominate
 the dry pipes, or steam-expanding apparatus, through which dry pipes
 I cause the steam, after it has been generated in the boiler in
 contact and consequently saturated with water, to pass with very great
 velocity, in order that it may imbibe a copious supply of additional
 heat without any addition of water, and by this additional heat to be
 expanded into a greater bulk of steam, of about the same expansive
 force that it had acquired in the boiler, by which means I obtain
 a greater volume of steam for use in the working cylinder than the
 boiler alone would supply; and in order still further to augment
 this volume of steam, I place the working cylinder within a case
 constituting a part of the flue or chimney, that the cylinder may be
 kept considerably hotter than the steam employed in it by absorbing a
 great portion of the heat remaining in the flue after having heated
 the boiler and the dry pipes, which heat would otherwise pass away out
 of the top of the chimney and be wasted, but by this arrangement is
 converted into a useful power by further expanding the steam in the
 cylinder.

 "And I do further declare, that in carrying this part of my said
 improvement into effect, I do not find it necessary to confine
 myself to any particular form of boiler, or arrangement of pipes, in
 which the steam is to be heated; but by preference, as being very
 compact in form, and economical of fuel in using, I make my boiler
 of a number of upright pipes, standing upon and communicating with a
 tubular ring placed around and a little below the fire-grate; these
 pipes all surround the fire-place, except two or three, the lower
 ends of which are elevated above the fire-door, but connected at the
 bottom by a branch pipe united to one of the adjoining upright pipes,
 thereby leaving an opening or place of access to the fire. These
 pipes all extend upwards to the height of several feet, according
 to the quantity of steam required to be raised, combined with local
 convenience, for it is obvious that the power of this boiler to
 raise steam may be increased either by increase of the length of the
 pipes, of their diameters, or of their numbers. And I do lay upon
 the upper ends of the pipes hereinbefore described and connect with
 them a tubular ring similar to that upon which the pipes stand, the
 two rings and the upright pipes forming together a vessel in which
 water has free communication by means of the bottom ring to stand at
 the same level in all the pipes, and the steam has free communication
 to pass from all the pipes into the upper ring; and I do, for the
 sake of obtaining great heat, place my system of dry pipes over the
 fire, and within the circular row of upright pipes of the boiler
 hereinbefore described; and I form my dry pipes in pairs, each pair
 constituting the figure that is well understood by the term inverted
 syphon; and I unite several of these syphons together by short bent
 pipes at the top, so as to constitute one long zigzag pipe, through
 which the steam must successively pass down and up the alternate
 legs of each syphon with great velocity, necessary for the rapid
 absorption of heat in its passage from the boiler to the working
 cylinder of the engine, the working cock, valves, or slide of which
 being united by a pipe of communication with that leg which is last
 in the succession of syphons; and I unite the first in succession of
 these inverted syphons with the upper tubular ring of the boiler by
 means of a bent pipe, in which a throttle-valve or cock is placed in
 order to limit the supply of steam, that it may have space in the dry
 pipes and working cylinder to expand in proportion as it receives
 additional heat; and I fix a safety-valve in communication with the
 boiler, and another in communication with the dry pipes; and I place
 around outside the boiler, at a small distance from the upright pipes,
 two cylindrical casings, one within the other, and fill up the space
 between the two casings with sand, ashes, or other material which
 conducts heat but slowly; and I close up the upper end of the casings
 over the boiler and the dry pipes with a covering in the form of a
 dome, and out of this enclosure I make the flue to pass to and around
 the working cylinder of the engine, whence the flue carries the smoke
 and little remaining heat away in any convenient manner; and I make
 my boiler-pipes, rings, and casings by preference of iron or copper,
 and my dry pipes of copper or other strong metal not liable to rapid
 oxidation by heat when in contact with steam; and I supply my boiler
 with water by means of a forcing pump, so adjusted as to keep the
 water of the proper height.

 "And I do hereby further declare, that the nature of my said
 invention, as regards the improvements in the application of
 steam-power to navigation, consists in the drawing of water into a
 receptacle placed near within the stern of the navigable vessel, which
 water is drawn in through an orifice in the stern with a moderate
 degree of velocity in the direction of the course of the vessel, and
 ejected with great force and speed in a direction opposite to the
 course of the vessel through the same orifice, reduced to about a
 quarter of the area by means of a valve opening as the water enters,
 and partially shutting as the water is ejected; and thus I propel the
 vessel with great force, derived from the recoil of the water set into
 rapid motion in a direction opposite to the course of the vessel,
 the rapidity of the jet of water to be at least equal to double the
 required speed of the vessel to be navigated.

 "And I further declare, that by preference I effect the purpose of
 receiving and of ejecting the water, and of deriving a motive force
 from its recoil, by means of a large vertical cylinder of cast iron
 or other metal, closed at both ends, in which a piston is forced up
 and down by a piston-rod sliding through a stuffing box in the lid,
 which piston-rod receives its motive force from a steam-engine; and
 I fix a tube into the after side of this cylinder, near the bottom,
 in communication with the space below the piston, which tube leads
 through the stern of the vessel, as low down as practicable, and opens
 on one side of the rudder; and I fix another tube into the after side
 of this cylinder, near the top, in communication with the space above
 the piston, which tube also leads through the stern of the vessel,
 as low down as practicable, but opens out on the other side of the
 rudder; and I place in the mouth of each of these tubes a valve
 opening inwards, to allow the water free entrance, equal to the bore
 of the tube, and partially shutting when the water is ejected, so as
 to reduce the opening through the stern to about one-fourth of the
 area of the tube.

 "And I do hereby further declare, that the nature of my said
 invention, as regards the improvement in the application of
 steam-power to locomotion, consists in the application of such a
 boiler, together with the expanding apparatus as aforesaid, to
 locomotive engines, whereby a diminished weight of boiler and quantity
 of water and fuel is obtained; and in farther compliance with the
 said proviso, I, the said Richard Trevithick, do hereby describe the
 manner in which my said invention is to be performed, by the following
 description of its various parts in detail, reference being had to
 the drawing annexed, and to the figures and letters marked thereon,
 that is to say:--

 "_Description of the Drawing._ [Plate XVII.]


 [Illustration: PLATE 17.

 TREVITHICK'S PATENT BOILER AND ENGINE, 1832.

  London: E. & F.N. Spon. 48, Charing Cross.      Kell Lith. London.]

 "Figure 1 represents a series of vertical sections through the various
 essential parts of the boiler, the dry pipes, the steam-pipe, the
 working cylinder, the propelling cylinder, and the flue, together
 with sections and views of other minor parts, serving to show the
 connections of the essential ones. The places at which these sections
 are taken are shown in Figure 2 by the dotted line from A to B, from
 B to C, from C to D, and from E to F. Figure 2 represents a plan of
 Figure 1, with the top coverings of the boiler and working cylinder
 removed. Figure 3 shows the manner of uniting the shorter upright
 pipes over the fire doorway with one of the adjoining ones, so as
 to give free circulation of the water in all the pipes. Figure 4
 represents three pairs of syphons, which in their places stand in
 a circular form, but in this Figure are shown as spread out into a
 plane, in order the better to explain their structure and joinings.
 Similar small letters and numbers of reference are used to denote
 similar parts in all the Figures; _a_, the upright boiler-pipes, the
 upright and lower ends of which are contracted to leave room for
 bolt-heads and nuts, without throwing the pipes too far asunder; _b_,
 the tubular ring having a flanch projecting inwards and outwards at
 the upper side, perforated with apertures upon which the upright pipes
 are bolted, and another flanch at the bottom, projecting inwards,
 to bolt the ring down to the foundation plate; _c_, the foundation
 plate; _d_, the fire-grate; _e_, the fire doorway; _f_, the upper
 tubular ring, having a flanch at the bottom projecting inwards and
 outwards, and perforated with apertures corresponding with the tops
 of the upright pipes upon which the tubular ring lies, and to all
 which it is bolted; _g_, the level of the water in the boiler-pipes;
 _h_, the dry pipes formed like inverted syphons, so as to require no
 joining at the lower part near the fire; one leg of each of the two
 syphons shown in Figure 1 is in section, and broken near the bottom;
 an outside view of the other leg appears partly behind the section;
 _k_, the short bent pipes, each bolted to two syphons, to unite
 them into one continuous pipe; _l_, the bent pipe uniting the upper
 tubular ring with the first in succession of the syphons; the proper
 situation for this pipe is that shown in Figure 2, but for the sake
 of clearness and simplicity in the drawing, it is shown in Figure 1
 as if on the left-hand pipe and syphon; _m_, the throttle-cock on the
 bent pipe _l_; _n_, the safety-valve lever, and weight on the same;
 _p_, the pipe of communication from the last in the succession of
 syphons to the working cylinder of the engine; _r_, the throttle-cock
 in the pipe _p_; _s_, a four-way cock, worked by the hand-gear,
 to direct the steam alternately under and over the piston; _t_,
 the safety-valve in communication with the dry pipes; _u_, the two
 cylindrical casings surrounding the boiler-pipes, the space between
 the two being filled up with a slow conducting medium; _v_, the
 domical covering over the cylindrical enclosure; _w_, the flue leading
 out of the enclosure into the casing of the working cylinder; _x_, the
 casing of the working cylinder forming a continuation of the flue;
 _y_, the further continuation of the flue to the chimney; _z_, the
 waste-steam pipe leading into the chimney; 1, the steam-pipes leading
 from the working cock into the top and bottom of the working cylinder;
 2, the working cylinder; 3, the piston with metallic packing; 4, the
 piston-rod passing down through a stuffing box at the bottom of the
 working cylinder, and also continuing downwards, to form the rod of
 the propelling piston; 5, the propelling cylinder; 6, the water or
 propelling piston; 7, the upper aperture leading to one of the tubes
 opening through the stern of the navigable vessel; 8, the lower
 aperture leading to the other tube, opening also through the stern of
 the navigable vessel; these apertures are made as wide as the cylinder
 will allow, in order that they may have but little depth, and not
 occasion an inconvenient length of the propelling cylinder; 9, a frame
 supporting the steam-cylinder upon the propelling cylinder; 10, the
 feed-pump for supplying the boiler with water; 11, an arm fastened on
 the piston-rod to work the feed-pump and hand-gear; 12, the hand-gear.

 "Now, whereas I claim as my invention, firstly, the interposing
 between the boiler and the working cylinder of the steam-engine a
 long many-curved heated pipe, through which the steam is forced to
 pass with great rapidity without being permitted to come in direct
 contact with water, by which arrangement the steam is made to absorb
 additional heat, and at the same time allowed to expand itself into a
 greater volume.

 "Secondly, placing the working cylinder of the engine within such part
 of the flue or chimney as shall ensure the cylinder to be kept hotter
 than the steam used in it, by which means the expanding of the steam
 is still further promoted.

 "Thirdly, propelling a navigable vessel by the force of the recoil
 produced from water received with a moderate degree of velocity, into
 a receptacle near within the stern, in the direction of the course of
 the vessel, and ejected with great velocity in a direction opposite
 to that course, the velocity of the jet being at least double the
 required speed of the vessel to be propelled, provided always that the
 same be effected in manner hereinbefore described.

 "Fourthly, applying a boiler combined with a steam expanding
 apparatus, as before described, instead of a boiler alone, to a
 locomotive engine, whereby the power of the steam is applied after the
 steam has undergone the expanding process, and whereby a diminution
 is effected in the weight of the boiler, and in the weight and
 consumption of water and of fuel."

The two great objects in this 1832 patent were superheating steam in
tubular boilers, and propelling ships by forcing a stream of water from
the stern at a speed of at least double that of the vessel. Similar
ideas may be traced in his patent of 1815, where a tubular boiler gave
superheated steam, and in 1809 his patent for propelling steamboats
"consists of a tube of considerable length disposed horizontally in
the water, and the stroke of rowing is made by means of a piston with
valves."

An engine of 100-horse power was ordered in Shropshire to be placed on
board the Government ship to test the value of those patents of 1831
and 1832. One consequence was that a gentleman who had helped this
scheme with his money wrote:--

 "My case with Trevithick is strictly this; he was represented to me as
 a man of property; and as to his talents for mechanics, no man could
 be in his company long without being struck with them. I was induced
 to trust him to the amount of nearly 500_l._, and I then learned for
 the first time that it was only on the possible contingency of a grant
 from Government that he relied for the payment of my claim."

A company called the New Improved Patent Steam-Navigation Company
was formed, of which Trevithick was a member, though apparently not
a subscriber, for a note in November, 1831, informed him that "if in
seven days he did not pay up his calls, his shares would be entirely
forfeited." This company, among other proposals, opened negotiations
for sending steamboats to Buenos Ayres to help in the commerce of the
port and inland river.

In 1832 the Waterwitch Company made experiments with those plans,
propelling by forcing water through pipes, since which a Government
ship of war called the 'Waterwitch' has been so propelled. Twenty years
ago the writer saw steamboats so propelled in daily use on the Meuse;
they needed no rudder, for by turning the mouth of the exit-water pipes
on either side of the ship it was made to turn in its length, or even
to move sideways.

Messrs. John Hall and Sons, of Dartford, also experimented on these
two patents, and from this the tubular condenser was called Hall's
Condenser. I think the boat it was first tried in was called the
'Dartford.'

Trevithick's difficulties in urging so many and great changes in marine
propulsion may be estimated by the acts of other engineers.

 "Mr. Rennie was engaged for many years in urging the introduction of
 steam-power in the Royal Navy. In 1817, we find him writing to Lord
 Melville, Sir J. Yorke, Sir D. Milne, and others on the subject. In
 July, 1818, he laments that he cannot convince Sir G. Hope or Mr.
 Secretary Yorke of their utility, but that he is persuaded their
 adoption _must_ come at last. On the 30th May, 1820, he writes James
 Watt, of Birmingham, informing him that the Admiralty had at last
 decided upon having a steamboat, notwithstanding the strong resistance
 of the Navy Board."[208]

[Footnote 208: 'Lives of the Engineers,' by Smiles, vol. ii., p. 267.]

So that Mr. Bennie, as professional adviser of the Navy Board, had
to persuade for three years, with a knowledge of Trevithick's prior
experiments, before active steps were agreed to; for twelve years had
then passed since Trevithick's nautical labourer and iron steamboat
had been tried on the Thames, and five since his experiments with the
screw-propeller.

An article in 'The Times' gives in strong contrast the relative value
of screw and paddle-wheels as propellers. The 'Syria' was originally a
paddle-wheel steamer, having oscillating cylinders worked with steam
of 25 lbs. on the inch, and Hall's tubular condenser; after a time
the paddle-wheels were removed for a screw-propeller, driven by two
steam-cylinders side by side, of different diameters, the high-pressure
steam exerting its full force in the small cylinder, and then expanding
in the larger cylinder. All the leading features in this improved
steamboat of the present day, such as high-pressure expansive steam in
one or two cylinders, with tubular condenser and screw-propeller, had
been publicly proved by Trevithick fifty years before.

[Illustration: PLATE 18.

COMPOUND MARINE ENGINE, 1871.

  London: E.& F. N. Spon, 48, Charing Cross.   Kell Bro^{s}. Lith.
  London.]

 "_Screw against Paddle._--An interesting and important trial trip
 has recently been made, which serves to exhibit the advantages of
 the screw over the paddle as a means of propulsion for ocean-going
 steamships. In 1863, the steamship 'Syria,' of 1998 tons, was built
 for the Peninsular and Oriental Company by Messrs. Day, Summers,
 and Co., and fitted with paddle-wheel engines of 450-horse power.
 The 'Syria' then attained a speed of 13·038 knots per hour, and the
 consumption of coal was at the rate of 45 tons per diem. The builders
 have lately converted her into a screw-steamer (for carrying the
 mails between Southampton and the Cape of Good Hope), who, without
 in any way disturbing the configuration of the hull, have fitted the
 'Syria' with compound inverted engines of 300 nominal horse-*power.
 These engines have two cylinders, respectively of 36 in. and 72 in.
 diameter, with a stroke of 4 ft. 2 in. On Monday last the 'Syria'
 attained an average speed of 12·637 knots, with a consumption of
 coal equivalent to 18 tons per diem; thus showing a difference of
 only 0·401 knot per hour, with a lessened power of 150 horses, and a
 saving in consumption of coal of 27 tons per diem; while the carrying
 capacity of the ship, arising from the economy of space in the
 engine-room, has been enormously increased, as she can now stow 1200
 tons of cargo against 500 tons previously."[209]

[Footnote 209: See 'The Times,' May 20th, 1871.]

Mr. Husband, of the firm of Harvey and Co., of Hayle, has obliged me
with the annexed sketch (Plate XVIII.) of a modern high-pressure steam
expansive compound marine engine, with surface condensers, on which the
grandsons of Trevithick are now working, to be placed in the 'Batara
Bayon Syree,' an iron yacht for an Indian Rajah, embracing the modern
improvements of direct-action compound engines, and illustrating the
principles which governed the constructors of the 'Syria.'

The first glance shows a seeming resemblance in outline to Trevithick's
patent drawing of 1832, having one cylinder above the other; but a
closer examination proves the application of the principles of his
patents of 1815 and 1831, embracing screw-propeller, direct-acting
engines, tubular boilers, high-pressure steam used expansively, and
condensation by cold surface preventing the necessity of using salt
water in the boilers.

This engine, in outline, has a strong likeness to Trevithick's
engines, going back even to his first patent of 1802,[210] followed by
the direct-action high-pressure steam yacht of 1806,[211] and again in
1808[212] by the iron steamer with direct-action long-stroke cylinders,
with highly expansive steam and surface condensers, to which, in
1815,[213] was added the patent compound expansive steam pole and piston
engine and screw-propeller, embodying during the first fifteen years of
the present century, both in principle and in detail, the most approved
form of marine steam-engine with fewness and simplicity of form of
moving parts; but compare it with the Watt patent engine, and its
difference is obvious; no beam or parallel motion, no injection-water
necessitating the air-pump, no low-pressure steam. The late Mr. William
Wilson, of Perran Foundry, son of Boulton and Watt's financial agent in
Cornwall, informed Mr. Henwood that he was with Mr. Watt when some one
stated that Mr. Trevithick was working his engine with steam of 40 lbs.
on the inch; when Mr. Watt replied, "I could work my engine with steam
of 100 lbs. to the inch, but I [would not] be the engineman."[214]

[Footnote 210: See vol. i., p. 59.]

[Footnote 211: See vol. i., p. 327.]

[Footnote 212: See vol. i., p. 386.]

[Footnote 213: See vol. ii., p. 103.]

[Footnote 214: Henwood, Address to the Royal Institution of Cornwall,
1871.]

Progressive experience, with increasing demand for economy and
speed, have caused the principles and the details of Trevithick's
steam-engines to be matters of national importance seventy years after
their discovery, for as far back as that he used highly-expansive
steam,[215] and on the question of a separate cylinder for expansion
as used in the modern steamboat combined engines, he wrote, "I think
one cylinder partly filled with steam would do equally as well as two
cylinders; that one at Worcester shuts off the steam at the first third
of the stroke, and works very uniformly with a considerable saving of
coal."[216] Those modern marine engines use about the same steam pressure
and expand about in the same proportion. With the direct action
from the piston-rod to the crank-shaft, the multitubular boiler and
screw-propeller, and the surface condenser perfected in 1831 and 1832,
at which time his construction of a marine steam-engine would have
been just what it now is forty years later. Those latter patents also
embrace the principle of superheating steam, practically shown many
years before,[217] and still used by marine engineers of modern times.

[Footnote 215: See Trevithick's letter, 22nd August, 1802, vol. i., p.
153.]

[Footnote 216: See Trevithick's letter, 5th July, 1804, vol. ii., p. 132.]

[Footnote 217: See Trevithick's letter, 16th May, 1815, vol. i., p. 370.]

In tracing the wisdom of his designs just before the close of an
eventful life, reference may be made to the trial of a common road
locomotive in 1871:--"Experimental trip of the Indian Government steam
train engine, 'Ranee,' from Ipswich to Edinburgh.--The results of the
trial with the 'Chenah,' though satisfactory so far as the engines
proper were concerned, were vitiated by the failure of the boiler; on
the completion of the second engine, the 'Ranee,' the field boiler and
variable blast-pipe were used; the boiler is about 4 feet diameter at
the bottom and 8 feet high."[218]

[Footnote 218: 'The Engineer,' 27th October, 1871.]

The form and dimensions of the exterior of the Ranee tubular boiler
are very similar to Trevithick's patent drawing and specification of
1832; even the variable blast-pipe was used by him in 1802.[219]

[Footnote 219: Trevithick's letter, 22nd August, 1802, vol. i., p. 153.]

The last years of Trevithick's eventful life were chequered with hopes
and disappointments when, in the early part of 1830, he wrote to his
friend Gerard:--

 "This morning I called here for the purpose of forwarding my
 information to the committee of the House. I called on Mr. Thompson
 to inform him what Mr. Gilbert said respecting it. His answer was,
 that the direct method would be by forwarding a petition in the
 way proposed when at the lobby. In consequence, I have forwarded
 the petition to Sir Matthew Ridley. Yesterday I took the coach to
 Highgate, by way of Camden Town, and of course had to walk up Highgate
 Hill. I found I was able to walk up that hill with as much ease and
 speed as any of my coach companions. However strange this maggot may
 appear in my chest and brain, it is no more than true. I wish among
 all you long-life-preserving doctors you could find out the cause of
 this defect, so as to remedy this troublesome companion of mine."

His health was breaking down, and his petition for a gift from the
public purse, so hopefully commenced two years before, was doomed,
after another year's bandying from pillar to post, to be forgotten and
unanswered.

  "DEAR TREVITHICK,     "EASTBOURNE, _December 26th, 1831_.

 "I am sorry to find that you have not any prospect of assistance from
 Government. I have not any copy or memorandum of my letter to Mr.
 Spring Rice, but it was to the effect of first bearing testimony to
 the large share that you have had in almost all the improvements on
 Mr. Watt's engine, which have altogether about trebled its power;
 your having made a travelling engine twenty-eight years ago; of your
 having invented the iron tanks for carrying water on board ship. I
 then went on to state that the great defect in all steam-engines
 seemed to be the loss by condensation of all the heat rendered
 latent in the conversion of water into steam. That high-pressure
 engines owed their advantages mainly to a reduction of the relative
 importance of this latent heat. That I had long wished to see the
 plan of a differential engine tried, in which the temperatures,
 and consequently elasticities, of the fluid might be varied on the
 opposite sides of the piston without condensation; that the engine you
 had now constructed promised to effect that object, and that in the
 event of its succeeding at all, although it might not be applicable
 to the driving water out of mines, yet that for steam-vessels and
 for steam-carriages its obvious advantages would be of the greatest
 importance; and I ended by saying that although it was clearly
 impossible for me to ensure the success of any plan till it had been
 actually proved by experiment, yet judging theoretically, and also
 from the imperfect trial exhibited on the Thames, I thought it well
 worthy of being favoured.

 "Your plan unquestionably must be to appoint some one with you, as Mr.
 Watt did Mr. Boulton, and I certainly think it a very fair speculation
 for any such person as Mr. Boulton to undertake.

 "It is impossible for me to point out any individual, as never having
 had the slightest motive with such or with manufacturers in any part
 of my life, I am entirely unacquainted with mercantile concerns. I
 cannot, however, but conjecture that you should make a fair and full
 estimate of what would be the expense of making a decisive experiment
 on a scale sufficiently large to remove all doubt; and that your
 proposal should be, that anyone wishing to incur that expense should,
 in the event of success, be entitled to a certain share of your
 patent; on such conditions some one of property may perhaps be found
 who would undertake the risk, and if the experiment proved successful,
 he would be sure to use every exertion afterwards for his own sake.
 With every wish for your success,

  "Believe me, yours very faithfully,
  "DAVIES GILBERT."

The statement of the President of the Royal Society, that the power of
the Watt engine had been trebled by Trevithick, brought him no gain.

He never troubled himself with politics, but the passing of the Reform
Bill caused him to suggest that it should be commemorated by a pillar
higher than had ever before been erected. The following memorandum is
in his own writing:--

 "'Morning Herald,' July 11th, 1832.

 "_National Monument in honour of Reform._--The great measure of Reform
 having become the law of the land, it is proposed to commemorate the
 event by the erection of a stupendous column, exceeding in dimensions
 Cleopatra's Needle, or Pompey's Pillar, and symbolical of the beauty,
 strength, and unaffected grandeur of the British Constitution.

 "In furtherance of this great object, a public meeting is proposed
 to be held, of which due notice will be given, to set on foot a
 subscription throughout the United Kingdoms, limiting individual
 contributions to two guineas, but receiving the smallest sums in aid
 of the design.

 "The following noblemen and gentlemen have signified their approbation
 of the measure:--His Grace the Duke of Norfolk, of Somerset, of
 Bedford; the Right Honourable Earl of Morley, of Shrewsbury, of
 Darlington; Lord Stafford; Sir Francis Burdett, M.P.; Joseph Hume,
 M.P.; R. H. Howard, M.P.; Win. Brougham, M.P.; J. E. Denison, M.P.; A.
 W. Robarts, M.P.; J. Easthope, M.P.; General Palmer, M.P."


 "Design and specification for erecting a gilded conical cast-*iron
 monument. Scale, 40 feet to the inch of 1000 feet in height, 100
 feet diameter at the base, and 12 feet diameter at the top; 2 inches
 thick, in 1500 pieces of 10 feet square, with an opening in the centre
 of each piece 6 feet diameter, also in each corner of 18 inches
 diameter, for the purpose of lessening the resistance of the wind,
 and lightening the structure; with flanges on every edge on their
 inside to screw them together; seated on a circular stone foundation
 of 6 feet wide, with an ornamental base column of 60 feet high; and a
 capital with 50 feet diameter platform, and figure on the top of 40
 feet high; with a cylinder of 10 feet diameter in the centre of the
 cone, the whole height, for the accommodation of persons ascending
 to the top. Each cast-iron square would weigh about 3 tons, to be
 all screwed together, with sheet lead between every joint. The whole
 weight would be about 6000 tons. The proportions of this cone to its
 height would be about the same as the general shape of spires in
 England.

 [Illustration: PLAN AND SECTIONAL ELEVATION OF PROPOSED REFORM
 COLUMN.]

 "A steam-engine of 20-horse power is sufficient for lifting one square
 of iron to the top in ten minutes, and as any number of men might work
 at the same time, screwing them together, one square could easily be
 fixed every hour; 1500 squares requiring less than six months for the
 completion of the cone. A proposal has been made by iron founders to
 deliver these castings on the spot at 7_l._ a ton; at this rate the
 whole expense of completing this national monument would not exceed
 80,000_l._

 "By a cylinder of 10 feet diameter, through which the public would
 ascend to the top, bored and screwed together, in which a hollow
 floating sheet-iron piston, with a seat round it, accommodating 25
 persons; a steam-engine forces air into the cylinder-column from a
 blast-cylinder of the same diameter and working 3 feet a second,
 would raise the floating piston to the top at the same speed, or
 five or six minutes ascending the whole height; the descent would
 require the same time. A door at the bottom of the ascending cylinder
 opens inwards, which, when shut, could not be opened again, having a
 pressure of 1500 lbs. of air tending to keep it shut until the piston
 descends to the bottom. By closing the valve in the piston it would
 ascend to the top with the passengers floating on air, the same as a
 regulating blast-piston, or the upper plank of a smith's bellows. The
 air apparatus from the engine should be of a proper size to admit the
 floating piston with the passengers to rise and fall gradually, by the
 partially opening or shutting of the valves in the top of the piston.
 Supposing no springs or soft substance for the piston to strike on at
 the bottom of the column-cylinder, descending 3 feet a second would
 give no greater shock than falling from 9 inches high, that being the
 rate of falling bodies, or the same as a person being suddenly stopped
 when walking at the rate of two miles an hour. The pressure of the
 air under the piston would be about 1/2 lb. on the square inch; the
 aperture cannot let the piston move above 3 feet a second, but this
 speed may be reduced to any rate required by opening or shutting the
 valves on the floating piston."

[Illustration: GENERAL VIEW OF REFORM COLUMN.]

To Trevithick's soaring genius nothing appeared very small, or very
large, or very costly; not even the cast-iron column 1000 feet high
covered with gold. The stone monument of London, 210 feet high, is
admired by many; others climb into the cross on St. Paul's Cathedral,
420 feet high; some make a long journey to the great Pyramids, 500 feet
high. How much more pleasant would be Trevithick's proposed floating
1000 feet upward on an air-cushion, controlled by his high-pressure
steam-engine, and having, from the loftiest pedestal of human art,
surveyed imperial London, to be again lowered to the every-day level at
a safe speed, regulated by valves closed by such simple acts as rising
from the seat; but should this be neglected, the passage of compressed
air escaping from under the piston-carriage would only allow of its
descent at a speed of 3 feet in a second, giving but the same shock on
bumping the bottom as jumping off a 9-inch door-step.

Perhaps the King in 1833 could not take an active part in advocating
a memento of the golden days of reform; but this is no reason why the
suggestion should have been so slightly noticed in 1862, to erect it in
memory of the good and wise Prince Albert.

Various meetings were held, and after nine months the plan had so far
advanced as to be placed before the King.

 "Sir Herbert Taylor begs to acknowledge the receipt of Mr. R.
 Trevithick's letter, with the accompanying design for a national
 monument, which he has had the honour of submitting to the King.

 "ST. JAMES'S PALACE, _1st March, 1833_."[220]

[Footnote 220: The column was suggested in 1862 as a suitable monument to
the memory of the late Prince Albert.]

Within two months from the date of the design for a gilded column
Trevithick had passed away. His family in Cornwall received a note,
dated 22nd April, 1833, from Mr. Rowley Potter, of Dartford, stating
that Trevithick had died on the morning of that day, after a week's
confinement to his bed. He was penniless, and without a relative by
him in his last illness, and for the last offices of kindness was
indebted to some who were losers by his schemes. The mechanics from the
works of Messrs. Hall were the bearers, and mourners at the funeral,
and at their expense night watchers remained by the grave to prevent
body-snatching, then frequent in that neighbourhood.

A few years after the funeral, the writer was refused permission to go
through the works to inquire into the character of the experiments that
had been tried, but the working mechanics were glad to see the son of
Trevithick, and their wives and children joined in the welcome as he
passed through the small town.

Trevithick's grave was among those of the poor buried by the
charitable; no stone or mark distinguished it from its neighbours. He
is known by his works. His high-pressure steam-engine was the pioneer
of locomotion and its wide-spreading civilization. England's mineral
and mechanical wealth on land or sea are indebted to its expansive
power, its applicability, and durable economy.

His comprehensive and ingenious designs, given to the world seventy
years ago,[221] are still instructive guides; and many of his works,
dating from the dawn of the present century, remained as active
evidences of his skill almost to the present day, with their
three-score years,[222] while some few reaching three-score years and
ten still remain good servants[223] in the solitude of the Peruvian
mountains, where no mechanical hand repairs the errors of human skill
or the wear and tear of time.[224]

[Footnote 221: See 1802 patent, vol. i., p. 128.]

[Footnote 222: See vol. i., pp. 222, 100, 82, 184.]

[Footnote 223: Agricultural engine, vol. ii., p. 68.]

[Footnote 224: See vol. ii., p. 220.]

If these material proofs fail to convince, the reader has but to ponder
on the bitterly natural reflections written by himself a few months
before his last illness to his friend Davies Gilbert:--

 "I have been branded with folly and madness for attempting what the
 world calls impossibilities, and even from the great engineer, the
 late Mr. James Watt, who said to an eminent scientific character
 still living,[225] that I deserved hanging for bringing into use the
 high-pressure engine. This so far has been my reward from the public;
 but should this be all, I shall be satisfied by the great secret
 pleasure and laudable pride that I feel in my own breast from having
 been the instrument of bringing forward and maturing new principles
 and new arrangements of boundless value to my country. However much
 I may be straitened in pecuniary circumstances, the great honour of
 being a useful subject can never be taken from me, which to me far
 exceeds riches."

[Footnote 225: Mr. John Isaac Hawkins.]




INDEX TO VOLUME II.


  A.

  ABADIA, Don PEDRO, 217, 219, 221, 229, 231, 236, 243, 245, 247.

  ABINGER, Lord, 303.

  ADAMS, Mr., 94.

  ADMIRALTY, 311, 338, 356, 358, 361, 372, 384.

  ADRIATIC STEAMER, 372.

  AËRATED STEAM, 7, 11.

  AGRICULTURAL ENGINE, 17, 18, 19, 36, 40, 41, 42, 47, 50, 53, 58.

  AGRICULTURAL MACHINE, 58.

  AIR-ENGINE, 292.

  AIR-PUMP, 19, 103, 122.

  AJERBI RIVER, 266.

  ALVERADO, 260, 261.

  AMALGAMATION, 261.

  AMPUTATION, 271.

  APPLICATION TO PARLIAMENT, 183, 317.

  AQUACATE, 267.

  ARISMENDI, Don JOSÉ, 217, 219, 221, 229.

  ARMSTRONG, Sir WILLIAM, 294.

  ARTHA, Captain, 60, 64, 69, 102.

  'ASP,' SHIP, 228, 239.


  B.

  BAILIFFS, 36.

  BANFIELD, Mr., 50.

  BANFIELD, Mr. J., 65, 74, 153.

  BARNES and MILLER, 375.

  BEDFORD, Duke of, 390.

  BEERALSTONE, 87, 102.

  BENNETTS, FRANK, 129.

  BICKLE, Mr., 65.

  BINNER DOWNS, 315, 323, 327, 369.

  BLACKLEAD, 4, 138.

  BLAST BY CYLINDER, 343, 352.

  BLAST BY SCREW, 341.

  BLAST-FURNACE, 6.

  BLAST-PIPE, 94, 141, 144, 210.

  BLEWETT, Captain, 174.

  BLEWETT, Mr., 51.

  BOILER, 7, 14, 19, 32, 41, 60, 66, 69, 74, 81, 84, 92, 102, 115,
      119, 124, 126, 138, 142, 145, 153, 156, 159, 169, 180, 183,
      213, 227, 290, 300, 308, 321, 327, 339, 343, 356, 357, 359,
      369, 377.

  BOLIVAR, President, 252, 254.

  BOOTH, Mr., 354.

  BORER OF ROCK, 24, 27.

  BOTTLE-NECK BOILER, 357.

  BREAKWATER, 22.

  BRIDGENORTH, 3, 87.

  BROUGHAM, Mr., 390.

  BRYANT, JOHN, 155, 163, 164.

  BUDGE, Mr., 126.

  BUENOS AYRES, 31, 227, 383.

  BULL, Mr., 84, 118, 213, 230, 237, 244, 246.

  BULLAN GARDEN, 116, 121, 155, 177.

  BURDETT, Sir FRANCIS, 390.

  BURRAL, Jun., Mr., 66.

  BURRAL, Sen., Mr., 102.

  BUSHEL, 46, 83, 96, 182.

  BUST, 245.


  C.

  CAMBORNE, 110.

  CAMPBELL and Co., 201, 230.

  CANAL BOAT, 17.

  CARLOOSE ENGINE, 116, 120, 155, 177.

  CARRIAGE-WHEELS, 207.

  CARTHAGENA, 272, 277, 279.

  CASTRO, NICOLAS, 260, 263, 280.

  CAUSON, WILLIAM, 159.

  CAXATAMBO, 252.

  CENTRAL ARGENTINE RAILWAY, 33.

  CERRO DE PASCO, 197, 201, 227, 229, 232, 255, 258.

  CHAIN-AND-BUCKET, 12.

  CHAIN-PUMP, 298, 317.

  CHAPER, Mr., 188.

  CHILI, 247, 249.

  CIRCULAR MOTION, 294.

  CLARK, HENRY, 78, 119, 141, 156.

  CLAY MILL, 1.

  COALBROOKDALE, 2, 3, 5, 138.

  COAL-LIFTING ENGINE, 365, 368, 370.

  COCHRANE, Lord, 282, 284.

  COLLINS, Mr., 95.

  COLOMBIA, 252.

  COMMON-ROAD LOCOMOTIVE, 110, 123, 126, 158, 300, 377.

  COMPETITION, 21, 33, 88, 92, 122, 132, 141, 150, 156, 374, 395.

  COMPOUND ENGINE, 103, 314, 386.

  COMPTROLLER OF THE NAVY, 342.

  CONDENSER, 134.

  COOKING BY STEAM, 368.

  COOK'S KITCHEN, 149.

  COPIAPO, 251.

  COPPER-ORE FURNACE, 10.

  CORALILLO, 262.

  CORDILLERA, 262.

  COST-ALL-LOST-ALL, 73.

  COST OF ENGINE, 5, 15, 34, 37, 43, 45, 46, 49, 61, 73, 83, 122,
      145, 149.

  COSTA RICA, 252, 260, 264, 278.

  COWIE, Mr., 87.

  CRICHTON, Mr. ALEXANDER, 359.

  CYLINDER, 19, 28, 39, 60, 67, 148, 210.

  CYLINDER-CASE, 370, 377.

  CYLINDRICAL BOILER, 60, 67, 69, 71, 74, 92, 102, 109, 119, 123,
      138, 140, 145, 148, 156, 163, 169, 186, 210, 227, 300, 308,
      344.


  D.

  DANIEL, Mr., 142.

  DARLINGTON, Earl of, 390.

  DARTFORD, 393.

  DAVEY, Captain JOHN, 118.

  DAVEY, Captain WILLIAM, 83, 101, 124.

  DAVIES, Mr., 86.

  DAY, Mr., 215.

  DEDUNSTANVILLE, Lord, 9, 18, 21, 39, 53.

  DENISON, Mr., 390.

  DERBYSHIRE, 3.

  DIXON, Mr., 128.

  DOBLE, Mr., 38.

  DOLCOATH, 1, 8, 10, 32, 40, 115, 116, 119, 141, 143, 145, 147, 150,
      153, 155, 157, 162, 168, 171, 175, 180, 194, 250, 307, 316, 321.

  DOMINGO GONZALES DE CASTAÑEDA, 234.

  DREDGER, 110, 143, 150, 297, 335.

  DRIVING WHEELS, 56.

  DUNDONALD, Lord, 111, 249, 282, 286.

  DUTY OF ENGINES, 73, 83, 96, 99, 105, 108, 109, 117, 124, 128, 142,
      157, 163, 166, 170, 175, 178, 181, 183, 187, 191, 205, 277, 290,
      305, 308, 310, 327, 333, 374.


  E.

  EASTHOPE, Mr., 390.

  ECCENTRIC, 208.

  'ECHO,' STEAMER, 356, 360.

  EDMONDS, Mr. RICHARD, 107, 183, 238, 245, 305.

  EDMONDS, Mr. THOMAS, 269.

  EDWARDS, Mr., 188.

  EMPSON, Mr., 279.

  'ENCYCLOPÆDIA BRITANNICA,' 182.

  ERSKINE, Mr., 130, 303.

  ESSENTIAL OIL, 202.

  EXETER BRIDGE, 23, 28, 54.

  EXPANSION, 19, 69, 85, 91, 100, 117, 128, 132, 143, 145, 148, 179,
      185, 205, 210, 325, 330, 352, 361, 376, 382.

  EXPLOSION, 153.


  F.

  FAIRBAIRN, Mr. JAMES, 273.

  FAIRBAIRN, Sir WILLIAM, 358.

  FALMOUTH, 27.

  FAREY, Mr., 180, 323.

  FAUCETT and Co., 375.

  FEED-POLE, 159.

  FEED-WATER, 39, 369, 373, 376.

  FIRE-ARMS, 254.

  FIRE-BARS, 20.

  FIRE-ENGINE, 134.

  FOLLETT, Sir WILLIAM, 358.

  FOUR-WAY COCK, 19, 29, 60, 67, 153.

  FOXES, Messrs., 22, 27, 30, 55, 88, 124, 151, 153.

  FRANCE, 365.


  G.

  GALLOWAY, Mr., 10.

  GAMBOA, 280.

  GEAR-WORK, 160.

  GEOLOGICAL SOCIETY, 245.

  'GEORGE AND VULTURE,' 366.

  GERARD, Mr., 255, 262, 265, 269, 271, 279, 280, 282, 286, 287.

  GIBBS, Mr., 129.

  GILBERT, DAVIES, 10, 23, 83, 93, 116, 118, 166, 183, 304, 307, 308,
      313, 319, 338, 363, 374, 388.

  GITTINS, Mr., 269.

  GLANVILLE, Captain, 119, 140, 159.

  GLOBULAR BOILER, 119, 124.

  GOSSETT, Colonel, 286.

  GOULD, Mr., 8, 27.

  GOVERNMENT, 154, 183, 311, 338, 388.

  GOVERNOR, 21.

  GREEN, Mr., 23, 29.

  GREENWICH, 124.

  GREGOR, Captain, 315.

  GREYTOWN, 271.

  GRIBBLE, 159, 176.

  GRINDING ENGINE, 2.

  GRIP, 56.

  GRIST MILL, 19.

  GROSE, Captain SAMUEL, 1, 60, 69, 101, 102, 111, 176, 178, 188, 321.

  GUAYAQUIL, 252.

  GUILDHALL, 365.

  GUN-CARRIAGE, 278, 282, 284, 286.

  GUNDRY, Mr., 17.

  GUNNERY, 289.


  H.

  HAARLEM LAKE, 302.

  HALL and SONS, 283, 393.

  HALL, Mr., 297.

  HALL, Mr. B. N., 273.

  HALL'S CONDENSER, 19, 322, 383.

  HALSE, Mr., 17.

  HARDY, Sir T. H., 339.

  HARRIS, Mr., 142, 152.

  HARROW BY STEAM, 40, 43, 58.

  HARVEY, Mr. HENRY, 23, 48, 52, 64, 88, 101, 152, 154, 188, 189,
      257, 298, 301, 302, 303, 356, 361, 385.

  HARVEY, Mr. NICHOLAS, 295.

  HAWKINS, Mr., 395.

  HAWKINS, Sir C., 16, 36, 39, 40, 45, 47, 54, 61, 171.

  HAYLE HARBOUR, 335.

  HAZELDINE, Mr., 52, 66, 151, 204, 215.

  HEARSE-BOILER, 155, 157, 163, 180, 308.

  HEAT LOST, 7.

  HEATING APPARATUS, 363.

  HENWOOD, Mr., 180, 185, 245, 360, 386.

  HERLAND, 31, 74, 83, 87, 91, 96, 99, 101, 105, 114, 118, 308, 310.

  HIGH PRESSURE, 19, 109, 119, 148, 150, 198, 271, 310, 376.

  HILL, Mr., 133.

  HODGE, Captain, 246, 249.

  HOLLAND, 110, 296, 299, 317, 333, 369.

  HOLMAN, Mr., 87.

  HOMFRAY, Mr., 4, 125, 128, 132, 134, 139, 140.

  HORIZONTAL CYLINDER, 19, 28.

  HORNBLOWER, 117, 170.

  HORSE-POWER, 36, 42.

  HOT BLAST, 11.

  HOT-HOUSE, 133.

  HOT-HOUSE STORE, 363.

  HOWARD, Mr., 390.

  HUME, JOSEPH, 390.

  HUSBAND, Mr., 385.

  HYDRAULIC CRANE, 385.


  I.

  ICE MAKING, 294.

  ILLNESS, 363, 388.

  ILLOGAN, 228.

  INCLINE, 267, 269.

  INJECTION, 19, 324.

  INVOICE, 220.

  IRON FURNACE, 8.

  IRON SHIPS, 286, 297, 299, 317.


  J.

  JAMAICA, 277.

  JASPER, Mr., 39, 66.

  JEFFRY, RICHARD, 159, 176.

  JENKIN, Mr., 83, 118, 166.

  JOAQUIN DE LA PEZULA, 233, 237.

  JOHNSTONE, Captain, 375.

  JOSÉ GONZALES DE PRADA, 236.

  JOSÉ LAGO Y LEMUS, 234.

  JUAN MORA RIVER, 266.

  JUDSON, Mr., 247.


  K.

  KENDAL, Mr., 39, 59.

  KENNY, Captain, 107, 228, 231.

  KING, Captain, 356, 361.


  L.

  'LA BELLE MACHINE,' 189.

  LAW PROCEEDINGS, 148, 150.

  LEAN, Mr., 117, 160, 164.

  LEAN, Mr. JOHN, 317.

  LEGASSACK, 102.

  LEITH, Captain, 230.

  LETTERS,--Edmonds, Mr. Richard, 106;
      228, Aug. 20, 1817;
      305, Nov. 7, 1827;
      305, Jan. 24, 1828;
      306, Jan. 12, 1853;
    Fairbairn, Mr. James, 272, Nov. 27, 1864;
    Gerard, Mr., 273, Nov. 17, 1827;
      280, Jan. 13, 1826;
      286, Feb. 21, 1828;
    Gilbert, Davies, 10, Jan. 20, 1811;
      93, Feb. 15, 1816;
      312, Dec. 25, 1831;
      388, Dec. 26, 1831;
    Hall, Mr. B. N., 273, Dec. 16, 1864;
    Harvey, Mr., 23, Nov. 26, 1812;
      101, April 18, 1816;
      154, Aug. 26, 1810;
    Hawkins, Sir C., 39, March 19, 1812;
    Homfray, Mr., 137, Dec. 26, 1804;
      139, Jan. 2, 1805;
    Liddell, Captain, 250, Nov. 3, 1869;
    Smith, Mr. T., 67, March 26, 1870;
    Thomas, Captain C., 162, March 29, 1858;
    Trethuoy, Mr. W., 68, May 17, 1872;
    Trevithick, Richard, 2, Sept. 23, 1804;
      6, Jan. 13, 1811;
      12, March 5, 1812;
      16, Dec. 5, 1812;
      16, April 28, 1812;
      18, Dec. 7, 1812;
      22, Nov. 8, 1812;
      24, Jan. 29, 1813;
      27, Feb. 4, 1813;
      28, Feb. 4, 1813;
      30, March 14, 1814;
      31, Dec. 9, 1815;
      33, Aug. 19, 1813;
      33, March 8, 1816;
      36, Feb. 13, 1812;
      41, April 26, 1812;
      45, May 1, 1812;
      47, June 13, 1812;
      49, June 17, 1812;
      50, July 5, 1812;
      51, Oct. 16, 1812;
      54, Jan. 26, 1813;
      59, Jan. 26, 1813;
      61, March 15, 1813;
      61, Aug. 19, 1813;
      80, July 8, 1815;
      86, Sept. 12, 1815;
      87, Sept. 29, 1815;
      88, Dec. 13, 1815;
      89, Dec. 23, 1815;
      91, Feb. 11, 1816;
      94, March 8, 1816;
      96, March 8, 1816;
      98, March 7, 1816;
      99, April 2, 1816;
      124, Oct. 1, 1803;
      128, Jan. 5, 1804;
      132, July 5, 1804;
      141, Feb. 18, 1806;
      145, March 4, 1806;
      146, March 21, 1806;
      171, March 10, 1812;
      173, March 27, 1813;
      193, May 20, 1813;
      198, May 22, 1813;
      199, June 2, 1813;
      200, June 8, 1813;
      201, June 11, 1813;
      202, June 19, 1813;
      203, June 23, 1813;
      204, Sept. 4, 1813;
      205, Sept. 7, 1813;
      206, Sept. 22, 1813;
      206, Oct. 1, 1813;
      207, Oct. 11, 1813;
      209, Oct. 23, 1813;
      212, Dec. 28, 1813;
      212, March 4, 1814;
      240, Feb. 15, 1817;
      243, Nov. 1817;
      251, 277, Nov. 15, 1827;
      281, Jan. 24, 1828;
      286, Feb. 21, 1828;
      289, April 19, 1830;
      292, June 18, 1828;
      294, June 29, 1828;
      295, July 31, 1828;
      303, Sept. 14, 1829;
      305, Jan. 24, 1828;
      306, Dec. 20, 1827;
      311, Dec. 24, 1831;
      315, Dec. 14, 1828;
      323, Dec. 30, 1828;
      332, July 27, 1829;
      335, Nov. 5, 1829;
      336, Nov. 14, 1829;
      339, Aug. 19, 1830;
      363, March 1, 1830;
      368, Jan. 24, 1829;
      372, June 10, 1830;
    Vivian, Captain A., 150, May 30, 1806;
    Williams, Mr. M., 111, Jan. 5, 1853;
    Williams, Messrs., 304, Nov. 14, 1820.

  LIBERALITY, 49.

  LIBERTY, WHEAL, 39.

  LIDDELL, Captain, 250.

  LIMA, 31, 32, 64, 80, 195, 206, 217, 218, 224, 226, 240, 247, 249,
      271.

  LINTHORN, Mr., 292.

  LOCOMOTIVE, 23, 26, 27, 39, 41, 43, 48, 50, 126, 133, 206, 217,
      271, 374, 379, 387, 388.

  LOGAN, Dr., 40.

  LONDON ENGINE, 5.

  LOSH, Mr., 95.

  LOW PRESSURE, 76, 140, 148, 157, 179, 180, 192, 395.

  LOWE, Mr., 277.

  LOWNDES, Lord, 287.


  M.

  MACHUCA, 262.

  MAGDALENA, 272.

  MAN AND HIS MAN, 361.

  MANCHESTER, 3, 138, 139.

  MAN'S POWER, 42.

  MARAZION, 180.

  MARRATT, Mr., 129.

  MATINA, 265, 267.

  MAUDSLAY, Mr., 375.

  MELLINEAR MINE, 75.

  MELVILLE, Lord, 24, 361.

  MEUX'S BREWERY, 111.

  MIERS, Mr., 247.

  MILLS, Mr., 339, 375.

  MINT ENGINE, 32, 201, 209, 217, 227, 239, 240, 243, 247.

  MITCHELL, Mr., 137.

  MODEL, 197.

  MOMENTUM, 20, 85, 91, 145, 149.

  MONT CENIS, 26, 293.

  MONTELEGRE, Mr., 269.

  MONTELEGRE RIVER, 266, 279, 280.

  MOORE, Dr., 34.

  MORLEY, Earl of, 390.

  MOYLE, Captain M., 307.

  MULE-POWER, 45, 47, 201.

  MURDOCH, 105, 118, 125, 126.


  N.

  NANKIVILL, Mr., 38.

  NAVY BOARD, 17, 41, 47, 372.

  NEATH ABBEY, 154, 199.

  NELSON, Lord, 121.

  NEVILLE, Mr., 157, 187.

  NEW STEAM NAVIGATION COMPANY, 383.

  NEWCASTLE-UPON-TYNE, 3.

  NEWCOMEN, 83, 114, 121, 157, 175, 211, 300, 319, 328.

  NICARAGUA LAKE, 269.

  NORFOLK, Duke of, 390.

  NUMBER OF ENGINES, 14, 148.


  O.

  OATS, JAMES, 111.

  ODGERS, Captain, 98.

  OPEN-TOP CYLINDERS, 19, 60, 208, 210, 211, 300, 363.

  OVAL TUBE, 21, 153.


  P.

  PADDLE-WHEEL, 384.

  PADRE ARIAS MINE, 262.

  PADSTOW ENGINE, 18, 27, 29.

  PAGE, Mr., 98, 99, 212, 214, 231, 241.

  PALMER, General, 390.

  PAPE, Mrs., 66.

  PARALLEL MOTION, 39.

  PATENT LAWS, 48, 128, 304.

  PATENTS, 343 of 1831;
    366 of 1831;
    376 of 1832.

  PAYNTER, Mr., 280.

  PENPONDS, 158.

  PENYDARRAN, 132.

  PERCEVAL, Mr., 108.

  PERRIER, Mr., 188.

  PERU, 210, 221, 252.

  PETITION TO PARLIAMENT, 306, 374, 388.

  PHILLIP, Mr., 89, 96, 99.

  PHILLIPS, HENRY, 90.

  PICKWOOD, Mr., 47.

  PINNEYS and AMES, 33, 49, 50, 51, 63.

  PINTO, DON ANTONIO, 280.

  PLOUGHING BY STEAM, 40, 54, 67.

  PLUMMER, BARHAM, and Co., 49.

  PLUNGER-POLE PUMP, 119, 198.

  PLYMOUTH BREAKWATER, 22, 23, 25, 27, 29, 30, 54, 195.

  PLYMOUTH DOCKYARD, 361.

  PNEUMATIC ELEVATOR, 392.

  POLDICE, 103.

  POLE-ENGINE, 31, 69, 80, 83, 90, 92, 99, 102, 176.

  POLE, Professor, 179.

  POOLY, WILLIAM, 158.

  POPULATION, 44, 265.

  PORTABLE ENGINE, 1, 5, 17, 22, 39, 50, 54, 170, 220, 309, 368, 370,
      374.

  POWER OF ENGINE, 14, 27, 42, 72, 76, 80, 86, 100, 115, 121, 143,
      148, 210, 211, 333.

  PRAED, Mr., 17, 48, 335.

  PRICE, Mr. JOSEPH, 96.

  PRICE, Sir ROSE, 64.

  PRONEY, Mr., 189.

  PUFFER-ENGINE, 1, 26, 32, 60, 74, 91, 102, 136, 140, 150, 154, 210.

  PUMPING ENGINE, 131, 148, 150, 171, 182, 189, 198, 207, 211, 217,
      220, 240, 257.

  PUMPS, 119, 124, 198, 207, 211, 333.

  PUNTA DE ARENAS, 260, 267.


  Q.

  QUARRYING, 22, 26.

  QUEBRADA-HONDA, 262.


  R.

  RAILWAY, 148.

  'RANEE' LOCOMOTIVE, 387.

  RASTRICK, Mr., 18, 54, 63, 66, 73, 87, 195, 200, 204, 212.

  RAWLINGS, Mr., 62.

  REES'S CYCLOPÆDIA, 181.

  REFORM COLUMN, 390.

  RENNIE, Mr., 24, 28, 31, 157, 181, 184, 187, 320, 339, 356, 358,
      372, 381.

  REYNOLDS, Mr., 10, 151.

  RHINE RIVER, 295, 297, 302.

  RICE, SPRING, 311, 388.

  RICHARDS, Mr., 19, 56.

  RIDLEY, Sir MATTHEW, 388.

  ROBARTS, Mr., 390.

  ROBERTS, Mr., 38.

  ROBINSON and BUCHANAN, 15, 16.

  ROCK BORING, 110, 206.

  'ROCKET,' 354.

  ROLAND, Mr., 196, 229.

  ROLLING MILL, 4, 132, 137, 209, 220.

  ROTTERDAM, 295.

  ROWE, GEORGE, 163.

  ROWE, Mr., 231.


  S.

  SAFETY-PLUG, 126.

  ST. AGNES HEAD, 59, 171.

  ST. AUBYN, Sir JOHN, 335.

  ST. IVES, 8, 16, 302.

  SALTRAM STREAM, 102.

  SAN JOSÉ, 267.

  SAN JOSÉ RIVER, 266.

  SAN JUAN DE NICARAGUA, 265, 269, 271.

  SAN MARTIN, 249.

  SANDYS, CARNE, and VIVIAN, 303.

  'SANSPAREIL,' 204.

  SANTA ROSA, 237.

  SAUNDERS, JAMES, 231.

  SAVERY, 114, 117, 319.

  SAWING BY STEAM, 41.

  SCREW-BIT, 27.

  SCREW-POWER, 293.

  SCREW-PROPELLER, 67, 384.

  SERAPIQUE, 265, 266, 280.

  SHAMMAL ENGINE, 121, 158, 166, 177.

  SHARRATT, Mr., 128.

  SHEFFIELD, Mr., 9.

  SHIPS OF IRON, 286.

  SILVER STATUE, 244.

  SIMS, Mr., 87, 102, 106, 150, 153, 176, 304.

  SINCLAIR, Sir JOHN, 17, 40, 41, 47.

  SING, Mr., 66.

  SMELTING FURNACE, 8.

  SMILES, Mr., 353.

  SMITH, Mr., 95, 241.

  SMITH, Mr. THOMAS, 66, 67.

  SMOKE BURNER, 20.

  SOHO, 179.

  SOMERSET, Duke of, 390.

  SOUTH AMERICA, 188, 195, 225, 227, 260, 309.

  SPADE BY STEAM, 40, 58.

  SPANISH GOVERNMENT, 205, 254.

  SPANISH MERCHANTS, 2.

  SPRING STEELYARD, 371.

  STEAM AGRICULTURE, 41, 43, 58.

    " BOAT, 17, 41, 329, 337, 356, 359, 375, 378.

  STEAM CRANE, 23, 27.

    "   CUSHION, 84.

    "   MASH-TUB, 14.

    "   NAVIGATION COMPANY, 295.

    "   PADDLE, 369.

    "   PLOUGH, 43, 58.

  STEAM PRESSURE, 1, 14, 20, 32, 34, 69, 74, 86, 91, 100, 102, 109,
      121, 123, 126, 142, 149, 153, 155, 179, 184, 192, 210, 309,
      330, 337, 358, 386.

  STEAM STONE-BORING, 25, 27, 29, 30.

    "   USERS' ASSOCIATION, 358.

  STEPHENSON, 272, 273, 279, 283, 353.

  STEVENSON, Mr. W. B., 247.

  STONE-BORER, 22, 24, 27.

  STONE-CRUSHER, 1.

  STONE-SPLITTER, 25.

  STOURBRIDGE, 132.

  STRAY PARK, 159, 166, 169, 175, 177, 183.

  STRENGTH, 90.

  STROKES, 20, 32, 36, 82, 91, 98, 100, 210.

  STUFFING BOX, 31, 79, 84.

  SUGAR-BOILING, 3.

  SUGAR MILL, 2, 50.

  SUPERHEATING STEAM, 290, 315, 324, 330, 376.

  SURFACE-AIR CONDENSER, 333, 335, 339, 341, 343, 374.

  SURFACE-WATER CONDENSER, 19, 316, 322, 324, 329, 332, 335, 338,
      341, 343, 374.

  SWAINE, CHARLES, 119.

  SYCOMBE, Mr., 232.

  SYMONDS, Captain, 339.

  'SYRIA,' STEAMBOAT, 384.


  T.

  TANKS, 388.

  'TASMANIA,' STEAMBOAT, 314.

  TAYLOR, Mr., 118, 180.

  TEAGUE, Captain, 197, 199, 229.

  TELFORD, Mr., 336.

  THOMAS, Captain CHARLES, 1, 74, 162.

  THOMAS, Captain JACOB, 157.

  THOMAS, Captain JOSIAH, 167.

  THOMPSON, Mr., 388.

  THORNE, Dr., 246.

  THRASHING ENGINE, 17, 21, 36, 38, 40, 42, 54, 61, 64, 68.

  TILLY, Captain, 229.

  TIN CROFT, 170, 173.

  TORMENTOR, 58.

  TREASURY, WHEAL, 152.

  TRECOTHICK, Mr., 47, 50.

  TRESKERBY, 102, 105, 107, 176, 305.

  TRETHUOY, Mr. WILLIAM, 68.

  TREVARTHEN, Captain, 213, 230.

  TREVITHICK, R., Jun., 158.

  TREVITHICK, Sen., 115.

  TREVITHICK, Mrs., 1.

  TREWITHEN, 38, 68.

  TRINITY BOARD, 143, 150.

  TUBULAR BOILER, 32, 115, 119, 153, 291, 308, 325, 339, 344, 359,
      376, 387.

  TYACK, Mr. JOHN, 295.


  U.

  UNITED MINES, 304.

  UPRIGHT BOILER, 41, 60, 290, 332, 339.

  UVILLE, Mr., 32, 63, 196, 200, 204, 208, 212, 214, 217, 221, 224,
      227, 229, 236, 240, 244, 245.


  V.

  VACUUM, 69, 157, 325.

  VALLEY PUFFER, 119, 142.

  VALVES, 160.

  VICEROY, 226, 251, 259.

  VIVIAN, Captain ANDREW, 52, 88, 96, 116, 125, 138, 140, 141, 152,
      154, 165, 306.

  VIVIAN, Captain HENRY, 90, 215, 230, 240.

  VIVIAN, Captain JOSEPH, 101, 142.

    "     Captain NICHOLAS, 157, 187.

    "     HENRY, 60.

    "     Mr. SIMON, 152.


  W.

  WARD, Mr., 361.

  WARREN, Mr., 66.

  WARSOP, Mr., 10.

  WATER-PRESSURE ENGINE, 13, 293, 310.

  WATER-PROPELLER, 378.

  WATERS, Mr., 250.

  WATERWITCH COMPANY, 383.

  WATKIN, Sir EDWARD, 273.

  WATSON, Mr., 247.

  WATT, 21, 33, 47, 75, 80, 83, 86, 92, 95, 98, 103, 105, 112, 115,
      118, 124, 125, 126, 128, 150, 156, 159, 163, 170, 175, 178,
      180, 183, 189, 191, 196, 211, 224, 230, 290, 300, 308, 312,
      319, 323, 328, 331, 352, 370, 374, 386, 388, 395.

  WELSH LOCOMOTIVE, 42, 68.

  WEST INDIA DOCKS, 3, 133.

  WEST INDIA ENGINE, 39, 45, 53, 63, 195, 201.

  WEST, JOHN, 160.

    "    WILLIAM, 158, 163.

  WHEAL, ABRAHAM, 148, 151, 153.

     "   ALFRED, 19, 54, 103, 105, 106.

  WHEAL CLOWANCE, 153.

    "   CONCORD, 103.

    "   DAMSEL, 103, 327.

    "   GENS, 117, 118, 155, 159, 169, 177.

  WHEAL JEWEL, 150.

    "   KITTY, 153.

    "   LIBERTY, 171.

    "   LUSHINGTON, 103.

    "   PROSPER, 69, 84, 106, 171.

    "   REGENT, 102.

    "   SEAL-HOLE, 170, 360.

    "   TOWAN, 157, 178, 185, 316, 327, 331, 360, 369.

  WHEAL TREASURE, 102.

   "   VOR, 83, 327.

  WHIMS, 17, 32, 39, 60, 119, 128, 141, 150, 153, 172.

  WHITEHEAD, Mr., 139.

  'WILDMAN,' SHIP, 217.

  WILLIAMS, Messrs., 22, 88, 106, 109, 124, 150, 153, 184, 281, 283,
      304.

  WILLIAMS, WILLIAM, 220.

  WILSON, Mr., 386.

  WINDING ENGINE, 2, 201, 208, 217, 220, 240.

  WINDMILL, 296.

  WOLLASTON, Dr., 293.

  WOOD, Mr., 4.

  WOOLF, ARTHUR, 80, 83, 86, 92, 96, 111, 180, 189, 316.

  WOOLWICH, 286, 335.

  WORCESTER, 133.


  Y.

  YANACANCHA, 238.

  YONGE, DON, 280.


  Z.

  ZUYDER ZEE, 302.


LONDON: PRINTED BY W. CLOWES AND SONS, STAMFORD STREET AND CHARING
CROSS




      *      *      *      *      *      *




Transcriber's note:

Inconsistencies in spelling and punctuation are as in the original.