Produced by Olaf Voss, Don Kretz, Juliet Sutherland, and
the Online Distributed Proofreading Team










SCIENTIFIC AMERICAN SUPPLEMENT NO. 299

NEW YORK, SEPTEMBER 24, 1881

Scientific American Supplement. Vol. XII, No. 299.

Scientific American established 1845

Scientific American Supplement, $5 a year.

Scientific American and Supplement, $7 a year.



[Illustration]




       *       *       *       *       *

     TABLE OF CONTENTS.

I.   ENGINEERING AND MECHANICS.--On the Progress and development
     of the Marine Engine.--Marine engines.--The marine
     boiler.--Steel boilers.--Corrosion of boilers.--How the marine
     engine may be improved.--Consumption of fuel.--Evaporative
     efficiency of marine locomotive boilers.--Screw propellers

     Steam Ferry Boats of the Port of Marseilles.--2 figures.--
     Transverse and longitudinal sections

     Opening of a New English Dock. 1 figure

     Improved Grain Elevator. 1 figure

     Improved Dredger. 1 figure.--Single bucket dipper dredger

     Railway Alarm Whistle

     Furnace for the Manufacture of Sulphide of Carbon. 1 figure

     Brouardel's Dry Inscribing Manometer. 1 figure.--Gas indication
     of manometer

     Centrifugal Apparatus for Casting Metals. 4 figures.--Centrifugal
     metal moulding apparatus

     Apparatus for the Manufacture of Wood Pulp. 2 figures.--Dresel's
     wood pulp apparatus

     Recent Progress of Industrial Science.--Presidential address,
     Convention of Mechanical Engineers

     The Hoboken Drainage Problem

II.  TECHNOLOGY AND CHEMISTRY--On some Recent Improvements
     in Lead Processes. By NORMAN C. COOKSON

     Apparatus Used in Berlin for the Preparation of Gelatine Plates.--
     I. Mixing apparatus.--II. Digestive apparatus.--III. Triturating
     apparatus--IV. Washing apparatus--3 figures

     How To Make Emulsions In Hot Weather. By A. L. HENDERSON

     The Distillation and Rectification of Alcohols by the Rational
     Use of Low Temperatures. By RAOUL PICTET.--1 figure.--Pictet's
     apparatus for the rectification of alcohol by cold

     The Removal of Noxious Vapors from Roasting Furnace Gases

     New Gas Exhauster. 1 figure

     Advance in the Price of Glycerine

     Analysis of Oils or Mixtures of Oils Used for Lubricating Purposes

     Nitrate of Amyl

III. ELECTRICITY, ETC.--The Electric Light in Earnock Colliery

     Lightning and Telephone Wires

     Conditions of Flames Under the Influence of Electricity

     The Electric Stop-Motion in the Cotton Mill

     Electrolytic Determinations and Separations. By ALEX, and M.
     A. VON REIS.--Determination of cobalt.--Nickel--Iron.--Zinc.--
     Manganese.--Bismuth.--Lead.--Copper.--Cadmium.--Tin.--Antimony.--
     Arsenic.--Separation of iron from manganese.--Iron from Aluminum

IV.  MEDICINE, SURGERY, ETC.--Treatment of Acute Rheumatism.
     By ALFRED M. STILLE, M.D.

     Method in Madness

     Simple Methods to Staunch Accidental Hemorrhage. By EDWARD
     BORCK, M.D.--Bleeding from upper arm.--From arteries in the
     upper third of the arm.--From the thigh.--From the foot

     Hot Water Compresses in Tetanus and Trismus

V.   AGRICULTURE, ETC.--The Cultivation of Pyrethrum and Manufacture
     of Powder

     Trials of String Sheaf Binders at Derby, England

     The Culture of Strawberries.--Garden culture.--Field culture

     Some Hardy Flowers for Midsummer

     The Time Consuming Match

VI.  ARCHITECTURE, ART, ETC.--Suggestions in Decorative Art.
     1 figure.--Silver ewer by Odiot, Paris

     Artists' Homes. No. l4.--Bent's Brook, Holmwood, Surrey, Eng.--
     6 figures.--Perspective, elevations, and plans

VII. OBITUARY.--Achille Delesse, eminent as geologist and mineralogist

       *       *       *       *       *




ACHILLE DELESSE.


The death of this distinguished man must be recorded. An interesting
_résumé_ of his labors by M. Daubree has appeared, from which we take
the following facts. After a training in his native town at the Lyceum
of Metz, which furnished so many scholars to the Polytechnic school,
Delesse was admitted at the age of twenty to this school. In 1839 he
left to enter the Corps des Mines. From the beginning of his career the
student engineer applied himself with ardor to the sciences to which
he was to devote his entire existence. The journeys which he undertook
then, and continued later, in France, Germany, Poland, England, and
Ireland, helped to confirm and develop the bent of his mind. He soon
arrived at important scientific results, and was rewarded, in 1845, by
having conferred to him by the university the course of mineralogy and
geology in the Faculty at Besançon, where Delesse at the same time
fulfilled the duties of engineer of mines. Five years later he returned
to Paris, where he continued his university duties, at first as deputy
of the course of geology at the Sorbonne, then as master of the
conferences at the Superior Normal School. Besides this, he continued
his profession of engineer of mines as inspector of the roads of Paris.
The first original researches of the young _savant_ concern pure
mineralogy; he studied a certain number of species, of which the
chemical nature was yet uncertain or altogether unknown, and his name
was appended to one of the species which he defined. He studied
also, and with success, the interesting modifications called
pseudomorphism--the mode of association of minerals, as well as their
magnetic properties. The attributes of a practical mineralogist aided
him greatly in the culture of a branch of geology to which Delesse has
rendered eminent services, in the recognition of rocks of igneous origin
and of others allied to them. He studied in the field, as well as by
investigations in the laboratory, for fifteen years, with an intelligent
and indefatigable perseverance, and, aided by the results of hundreds of
analyses, eruptive masses of the most varied kind, the knowledge derived
from which threw light upon the principles of science, from granites
and syenites to melaphyres and basalts. After thirty years of study
and progress, other _savants_, without differing from him, progressed
further in the intimate knowledge of rocks; but the historian of
science will not forget that Delesse was the precursor of this order
of research. His studies of metamorphism will long do him honor. The
mineralogical modifications which the eruptive rocks have undergone in
the mass are the permanent witnesses which attracted all his attention.
The chemical comparison of the metamorphic with the normal rock pointed
out distinctly the nature of the substances acquired or lost. One of the
principal results of these analyses has been to lessen the importance
attributed until then to heat alone, and to show in more than one case
the intervention of thermal sources and of other emanations from below,
to which the eruptive rocks have simply opened up tracks.

It is not only upon subjects relating to the history of rocks that
Delesse has touched. Witness his work on the infiltration of water, as
well as his volume relating to the materials of construction, published
on the occasion of the Exhibition of 1855. The nature of the deposits
which operate continually at the bottom of the sea offers points of
interest which well repay the labor of the geologist. He finds there,
indeed, a precious field to be compared with stratified deposits; for
in spite of the enormous depth to which they form a part of continents,
they are of analogous origin. Delesse laboriously studied the products
of the innumerable soundings taken in most of the seas. He arranged the
results in a work which has become classical with the beautiful atlas of
submarine drawings which accompany it. Though he never slackened in his
own especial work, he made much of the work of others. The "Revue des
Progrès de la Géologie," with which he enriched the "Annales des Mines"
for twenty years, would have been sufficient to engross the time of a
less active scientific man, and one less ready to grasp the opening of a
discovery. This indefatigable theorist never neglected the applications
of science: the nature and the changes of the layers which form the
under earth; the course and the depth of the subterraneous sheets of
water; the mineralogical composition of the earth's vegetation, were
represented by him on several charts and plans drawn out in proper form.
His maps which follow the route of many of the great French lines of
railway explain the kind of soil upon which they are laid, and are of
daily use. In the pursuit of his numerous scientific works, Delesse
never failed in discharging his duties in the Corps des Mines. Having
in 1864 quitted the service of the Government of Paris, which he had
occupied for eighteen years, he was made professor of agriculture, of
drainage, and irrigation, at the School of Mines, where he established
instruction in these before being called to found the course of geology
at the Agricultural Institution. Promoted to be Inspector-General of
Mines in 1878, and charged with the division of the south east of
France, he preserved to the end of his life these new duties, for which,
to the regret of the School of Mines, he gave up his excellent lessons
there. During the year of 1870 Delesse fulfilled his duties as a
citizen, as engineer in preparation of cartridges in the department.

His nomination to the Academy of Sciences, which took place on the 6th
of January, 1879, satisfied the ambition of his life. He was for two
years President of the Central Commission of the Geographical Society;
he was also President of the Geological Society. He was not long to
enjoy the noble position acquired by his intelligence and his work.
He suffered from a serious malady, which, however, did not weaken his
intellect, and he continued from his bed of suffering to prepare the
reports for the Council-General of Mines, and that which recently he
addressed to the Academy on the occasion of his election. The greatness
and the rectitude of mind of Delesse, his astounding power of work, his
profound knowledge of science, his sympathetic sweetness, which were
associated with sterling modesty and loyalty of character, made him
esteemed and cherished throughout his whole career. He died on the 24th
of March.--_The Engineer._

       *       *       *       *       *

[Illustration: SUGGESTIONS IN DECOTATIVE ART.--SILVER EWER, BY ODIOT,
PARIS.

(From The Workshop)]

       *       *       *       *       *




THE ELECTRIC LIGHT AT EARNOCK COLLIERY.


On the afternoon of August 9, Earnock Colliery, near Hamilton, belonging
to Mr. John Watson, of Earnock, was the scene of an interesting
ceremonial which may well be said to mark a new era in mining annals.
In proceeding to win the rich mineral wealth of his estate, Mr. Watson
determined that, in respect of fittings, machinery, and general
appointments, it should be a model, and he has been highly successful
in giving practical effect to his aims. Among other things, he early
resolved to, if at all practicable, substitute the electric light for
the ordinary mode of illuminating the workings, and after investigating
the various systems, he decided on giving that of Mr. Swan a trial.
Accordingly, since April last, Messrs. D. & E. Graham, electrical
engineers, Glasgow, have been engaged fitting up the Swan incandescent
lamp, with modifications, to adapt it for safe use in the mine, and on
Tuesday the inauguration of the new light took place in presence of a
large company of leading gentlemen from Glasgow, Hamilton, and the West.
Arrived at the colliery about half-past one o'clock, the visitors were
received by Mr. Watson, and after a brief space spent in inspecting
the three magnificent winding and fan engines, the Guibal fan, and the
framework for screening the coal, they were conducted by Mr. James
Gilchrist, manager, down into the workings in the ell seam at a depth
of 118 fathoms. Here at the pit bottom, in the roads and at the face,
twenty-one Swan lamps were burning, giving forth a brilliant, steady
flame, the luminosity of which, while sufficient to supply the desired
light, had none of the disagreeable intensity associated with most
systems of electric lighting. Besides the pear-shaped Swan lamp, in
which the glowing or incandescence is carried on _in vacuo_, there is an
outer lantern, the invention of Mr. David Graham, consisting of a strong
glass globe, air-tight, protected with steel guards. Each lamp was also
connected with two different forms of Graham's patent safety air tight
contacts and switches for cutting off and letting on the current, the
effect of which, it is believed, would be to render the lamps quite
safe, even in the presence of explosive gas. At first the intention
was to employ the fan-engine to drive the dynamo-electric machine or
generator, but this was departed from, and an engine of 12 horse-power
was erected in the workshops on the surface for the purpose. From the
generator the electric cables, two in number, are conducted along the
roof of the workshops over ordinary telegraph poles to the pit-head at
No. 2 shaft, and thence down into the workings. From the ridge of the
workshops to the pithead, a distance of several hundred yards, the
cables consist of ordinary copper wire, three-eighths of an inch in
diameter; inside the workshop and below ground, to allow of their safe
handling, they are composed of insulated wires, while on the way down
the shaft they are inclosed in a galvanized tube. Near the bottom of the
shaft, branches are taken off to supply light to the principal roadways
and to the haulage engine-room, the main cables being carried into one
of the sections of the mine a distance of half-a-mile. After a careful
inspection of the lamps at the pit bottom, the party were photographed
in three groups, with the aid of the electric light, by Mr. Annan, of
Glasgow, who may well be credited with the distinction of being the
first to exercise his skill in the bowels of the earth. They were
then led to the haulage engine-room and into the workings, where they
witnessed the effects of the light. At the latter point, while, of
course, the visitors were at a safe distance, a shot was fired, bringing
down a large mass of coal. Having spent fully an hour below ground, the
party returned to the surface.--_Colliery Guardian_.

       *       *       *       *       *




LIGHTNING AND TELEPHONE WIRES.


M. Bede, of Brussels, has an article in _L'Ingénieur-Conseil_ on the
above subject. He considers that a system of such wires forms the best
and most complete security against lightning with which a town can be
provided, because they protect not only the buildings in which they
terminate, but also those over which they pass. At each end they
communicate with the earth, and thus carry off safely any surplus
of electricity with which they may become charged. It is, however,
important that they should be provided with lightning conductors of
their own, to carry off such surplus directly from the transmission wire
to the earth wire, without allowing it to pass through the fine wires of
the induction coils, which it might fuse.

Such lightning conductors usually consist of a toothed plate attached to
one wire, close to another plate not toothed attached to the other wire.
The copper even of such a conductor has been melted by the powerful
current which it has carried away. In telephonic central offices, M.
Bede has seen all the signals of one row of telephone wires fall at the
same moment, proving that an electric discharge had fallen upon the
wires, and been by them conveyed to earth.

This fact shows that wires, even without points, are capable of
attracting the atmospheric electricity; but it must be remembered that
there are two points at every join in the wire. M. Bede insists strongly
upon the uselessness of terminating lightning conductors in wells,
or even larger pieces of water. The experiments of MM. Becquerel
and Pouillet proved that the resistance of water to the passage of
electricity is one thousand million times greater than that of iron;
consequently, if the current conveyed by a wire one square mm. thick
were to be carried off by water without increased resistance, a surface
of contact between the wire and the water of not less than 1,000 square
meters must be established.

It is obvious that a wire let down into a well is simply useless. On
the two-fluid theory, it offers no effectual way of escape to the
terrestrial electricity; according to the older views, it would be
absolutely dangerous, by attracting more electricity from the clouds
than it could dispose of. The author advocates connecting lightning
conductors with water or gas pipes, which have an immense surface of
contact with the earth.

       *       *       *       *       *




CONDITION OF FLAMES UNDER THE INFLUENCE OF ELECTRICITY.


The experiments of the author have been principally directed to the
alterations in shape and color produced in a flame when under the
influence of positive or negative electricity. The flames were arranged
so as to form one electrode of a frictional machine. When charged with
positive electricity the flame became more blue, narrower, and pointed
at the top, while little or nothing of the result was observed in
negative flames.

A peculiar result is that the end of a negative flame returns to its own
conductor, and that, according to the intensity of the electricity, and
also depending on the width of the burner, this turning back of the
flame is either intermittent or constant. Most noticeable are these
results:

When the flame rises from a circular burner, or when burning round a
metallic cylinder, in the latter case it returns to the metallic surface
according to the intensity of electricity in an arc or angle, while the
point of the flame divides into two branches, which separately perform
more or less equal movements. If a body connected to the earth by a
conducting wire is held opposite the flame at some distance, the flame
will in all cases bend toward it; as the body is brought closer,
the flame, if negative, will be repulsed, and, if positive, will be
attracted, at least the upper luminous part of the flame, while the
lower dark body of flame is also repulsed.

This phenomenon explains why a positive flame will burn through wire
gauze, while a negative flame remains below the gauze. The positive
flame becoming pointed explains the fact that this will drive a small
fan wheel, while a negative flame will only just move it.

All these results are most prominently obtained with a pure gas flame, a
stearine, wax, or tallow candle, very indifferently with a spirit flame,
and least from a Bunsen flame rich in oxygen. They may not only be
obtained with flames electrified direct, but also when placed under the
influence of a long "Holtz" machine.

A flame placed between two small disks on the machine bends toward the
negative pole, becomes widened, and, at a certain point of electric
intensity, commences to vibrate and oscillate, exhibiting a peculiar
stratification. Since these phenomena are also least observed in flames
rich in oxygen, it appears to be a general law that carbon and hydrogen
are more strongly attracted by the negative pole, while oxygen is
more attracted by the positive pole, probably like in all polar
differentially attractions, in consequence of a peculiar unipolar
conductivity of the substances.

The return motion of the flame the author explains thus: The point
of the flame loses more electricity by influence than it receives by
conductivity. A paper strip fixed at one end to a large ball shows
similar movements when its free end is pointed and made conductive.
Why principally the negative flame returns may be explained in two
ways--either the point of the flame loses much by radiation, or the base
of the flame is a bad conductor. The former explanation would agree with
the experiments made by Wiedemann and Ruhlmann, the latter with Erdman's
theory of unipolar conductivity of flames. This theory is still further
supported by the resistance on the negative electrodes noticed by
Hittorf, which almost explains Erdman's experiments, because if negative
electricity enters a flame with greater difficulty, then positive
electricity must leave a flame with difficulty.--_W. Holtz, in
Wiedemanris Beiblätter to Poggendorfs Annalen._

       *       *       *       *       *




THE ELECTRIC STOP-MOTION IN THE COTTON MILL.


The number of inventions for use as stop-motions in and about the
various machines in the cotton mill has been to a certain extent
something like the search after perpetual motion. Very available and
quite satisfactory stop-motions have for a number of years been employed
wherever the thread or sliver has been twisted so that strength was
given it to resist a slight amount of friction, but the main trouble
in the mill has been done after the sliver leaves the railway head and
during its transit in the various processes employed between the railway
head and the spinning frame or mule. Every carder or spinner knows that
where an injury comes to the sliver because the sliver is soft, but
partially condensed and very susceptible to injury, the injury is
magnified and multiplied in every successive process. Virtually the
field was long since abandoned for an accurate quick-working motion that
should be applicable to any and all the machines and to every sliver or
strand of the machine.

This invention was solved practically about two years since, and is
now being employed as applied to drawing frames, doublers, speeder,
intermediate, and slubber. It is a very cunning mechanical appliance,
too, and has found favor to a great extent in England, where several
thousand heads of drawing and speeders are already supplied.

This invention was exhibited at the Centennial in 1876, although in a
somewhat crude state. Since that time it has been materially improved,
and mechanically is very nearly perfect now. Many attempts have been
made to apply a stop motion, which should be quick in its movement and
accurate in its result, to carding engines or the card, not one of
which, until the application of electricity, was worth the time spent in
putting it on. With the electric motion, however, all this is changed,
and the electric attachments are not of necessity so fragile as to be
un-mechanical or to be not practical. The advantage has also been
taken, in a mechanical way, of using cotton as one element, and, being
non-conducting, so that no trouble shall arise from contact with the
working parts of the electrical apparatus with the cotton itself.

To take into consideration all the possibilities that exist from the
railway can to the front of the fine speeder is not needed by the
practical reader, and would be useless to any other. The principle of
this invention is the supplying of a magneto-electric current from
a small magneto-electric machine attached to the card, speeder, or
whatever machine it may be applied to which generates the current, and
this machine is driven by a small belt from the main driving shaft.
The machine in itself weighs but a few pounds, and can be driven by a
half-inch or three quarter-inch belt, and requires a little more power
than a light-running sewing machine.

One pole of the magneto-electric machine is connected by means of a rod
or wire to the machine frame upon which it is to be used, and the
other pole to the electromagnet in the ordinary way of conductivity
of current, which means stretching the wire from one to the other. An
armature is arranged so that when a thread is broken or a sliver or a
strand of roving, the armature drops into a ratchet wheel; this ratchet
wheel is made to revolve by the belt, and whenever it is impeded or
stopped in its course it acts upon mechanism which throws the driving
belt of the machine upon the loose pulley. Electrical contact is made by
a very simple contrivance, and these attachments are only to act in the
case of a breakage of a thread or strand.

As applied to a card, the calender rolls are both connected, one with
the negative and one with the positive pole; when the sliver of cotton
is between the calender rolls there is no connection, but if the sheet
breaks down between the cone and the calender roll, the moment the
calender rolls come in contact the electrical attachment operates and a
stoppage ensues; and in the case, as with the American system, where a
number of cards are used in a railway, this electric contact may be used
for either one of two purposes-to stop the feeding of cotton into the
card, or to ring a bell sharply and continue ringing it until the sliver
is put between the calender rolls again and the card set to delivering
cotton.

In drawing frames it may be attached so that, in the case of a breakage
between the front roll and the calender roll, the electric machine acts;
in the case of a lap upon one of the rolls or one end of the roll, or
in case of breakage of the sliver at the back of the machine, in either
case a stoppage would be instantly produced.

In being applied to the slubber a breakage either at the front or back
can be arranged for. Upon intermediates the breakage of either one of
the strands, if the machine was running two into one, from the creel to
the roller, would cause the stoppage of the machine, or the breaking or
tangling of ends between the front roll and the nose of the flier.

There are many other places where this motion can be applied. With
mechanical means we require motion; with electricity we require simple
contact of two differently arranged surfaces, and this can always be
had by letting the cotton drop out from between the rollers; no radical
changes are necessary, and we are glad to find that this electrical
attachment is meeting with a very good success in England, France,
and, so far, in the United States, and, undoubtedly, further and more
extended opportunity will be found for this application.--_Textile
Record_.

       *       *       *       *       *




ON THE PROGRESS AND DEVELOPMENT OF THE MARINE ENGINE.

[Footnote: A paper recently read before the Society of Mechanical
Engineers by F.C.Marshall.]


The author began by referring to a paper read at the Liverpool meeting
in 1872, by Mr. F. J. Bramwell, F.R.S., on "The Progress effected in
Economy of Fuel in Steam Navigation, considered in Relation to Compound
Cylinder Engines and High-pressure Steam;" then proceeded to continue
the subject from the date of that meeting, to trace out whether any, and
if so what, progress had been made; further, to consider whether or no
we have reached the finality so strongly deprecated by Sir Frederick
Bramwell in the discussion referred to, and, if not, then in what
direction we are to look for further development.

From a table it would seem that the steam pressures are now much higher,
the boilers have less heating surface, and the cylinders are much
smaller for the indicated horsepower developed than in 1872; and at the
same time the average consumption of fuel is reduced from 2.11 lb. to
1.828 lb., or by 13.38 per cent.


MARINE ENGINES.

The author then briefly described the modern marine engine and boiler.
The three great types of compound engines may be placed as follows in
the order of their general acceptance by the shipowning community: (1)
The two-cylinder intermediate-receiver compound engine, having cranks at
right angles. (2) The Woolf engine in the tandem form, having generally
the high-pressure and low-pressure cylinders in line with each other,
but occasionally alongside, and always communicating their power to one
crank. Such a pair of engines is used sometimes singly, oftener two
pairs together, working side by side to cranks at right angles; recently
three pairs together, working to cranks placed 120 deg. apart. The
system affords the opportunity of adding yet more engines to the
same propeller to an indefinite extent. (3) The three cylinder
intermediate-receiver compound engine, with one high and two
low-pressure cylinders, the steam passing from the high-pressure
cylinder into the receiver, and thence into the two low-pressure
cylinders respectively. The cranks are placed at equal angles apart
round the crank shaft, so as to balance the forces exerted upon the
shaft.

These three types may be said to embrace all the engines now being
manufactured in this country for the propulsion of steam vessels by the
screw propeller. In their leading principles they also embrace
nearly all paddle engines now being built, whether the cylinders be
oscillating, fixed vertically, or inclined to the shaft.

The compound engine, in fact, in one of these three forms, may now be
said to be universally adopted in this country; and the question of the
relative value of simple expansion in one cylinder, and of compound
expansion in two or more cylinders, which agitated the minds of some of
our leading engineers ten years ago, is now practically solved in favor
of the latter.


THE MARINE BOILER.

The marine boiler of to-day is in all its main features the same as it
was ten years ago. The single-ended boiler, made with two, three, and
sometimes four furnaces, is the simplest form, and for all powers
under 500 indicated horse power is the most generally adopted. The
double-ended form is largely used. It has been found more economically
efficient than the single-ended form, by as much as ten per cent, in the
writer's own experience. It is generally adopted for engines of large
power, but for small power is inconvenient, owing to its occupying more
room lengthwise in the vessel, and also involving two stokeholds and
therefore more supervision. At one time great difficulty was found
in keeping the bottoms of boilers of this kind tight. Owing to their
length, the unequal expansion due to different temperatures at the
top and bottom caused severe racking strains on the bottom seams and
riveting--so severe in some cases as to rend the plating for a large
part of the bottom circumference of the shell. This difficulty has now
been to a large extent got over, in consequence of the greater attention
given to the form and direction of the water spaces in the boiler
itself, so as to induce circulation of water; the introduction of the
feed-water at the top instead of near the bottom; the more careful
management now usual on the part of engineers; and lastly, the use of
larger plates, welded horizontal seams, drilled rivet holes, and more
perfect workmanship throughout. A modification of double-ended boiler is
that introduced by Mr. Alfred Holt. It has many decided advantages,
but is costly to make. The formation of the two ends into separate
fire-boxes leaves the bottom of the boiler free to adapt itself to the
variations of temperature to which it is exposed. The separation of the
furnaces from the combustion chamber, excepting through the opening
afforded by a connecting tube, is an advantage in the same direction,
and avoids almost entirely the racking strains due to irregular furnace
action. The weight of water carried is less, and that of the boiler
may also be made less; while the elliptical form of the two ends gives
greater steam space.

A type of boiler largely used in her Majesty's Navy, somewhat like a
locomotive boiler, is highly efficient in regard to weight and power
developed. Many examples have yielded one indicated horse-power in the
cylinders for every three square feet of heating surface, under natural
draught and with a very moderate height of funnel; and this with a
consumption of fuel not exceeding 2½ lb. per indicated horse-power per
hour under a working pressure of 60 lb. With the aid of a steam jet in
the funnel, the heating surface per indicated horse-power has fallen
below 2½ square feet. The large water surface afforded for escape
of steam secures almost entire freedom from priming, without the
incumbrance of steam domes; and the large combustion chamber allows of
the thorough combustion of the gases before their passage through the
tubes. The locomotive type of boiler has lately occupied the writer's
attention, with a view to its more definite introduction into marine
work. The difficulties, however, which lie in the way of applying it to
steamers going long voyages are very great. The principal difficulty
lies in the necessity of burning a large quantity of fuel in a very
limited space and time. This can only be done either by direct pressure
or exhaust action applied at the furnace. In other words, we must either
exhaust the funnel, which will absorb a large amount of power, but would
be comparatively easy of application; or our stokers, as is the case
with our miners, must work under a pressure of air.


STEEL BOILERS.

The writer stated that his experience in the manufacture and working of
steel boilers was satisfactory. Many steel boilers of sizes varying from
six feet diameter to fourteen feet six inches diameter have left the
works at St. Peter's since 1877, when the first was made; and in no
case has there been a failure of a plate after being put into a boiler,
either in the process of manufacture or in working at sea. The mode
of working is as follows: For shell plates, from five-eighths inch
to seven-eighths inch thick, to warm each to a dark red heat before
rolling, having previously drilled a few holes to template for bolting
the strakes together; the longitudinal seams are usually lap joints
treble riveted, requiring the corners to be thinned, which is done after
rolling. The furnace plates are generally welded two plates in length,
and flanged to form Adamson rings, and at the back end to meet the tube
plate; the back flame-box plates are flanged, also the tube plates and
front and back plates; and wherever work is put on to the plate it
is annealed before going into the place. The rivet holes are drilled
throughout. In the putting together the longitudinal seams of the
thicker plates of the shells, great care is always taken to set the
upper and under plates for the lap to their proper angle before they
are bolted together, a point generally overlooked by the practical
boilersmith.


CORROSION OF BOILERS.

The question of corrosion is one which is gradually being answered as
time goes on; and so far very satisfactorily for steel. Some steel
boilers were examined a few weeks ago which were among the first made;
and the superintending engineer reports: "There is no sign of pitting
or corrosion in any part of the boiler; the boilers are washed out very
carefully every voyage, and very carefully examined, and I cannot trace
anything either leaking or eating away. No zinc is used, only care in
washing out, drying out, and managing the water." This is the evidence
of an engineer with a large number of vessels in his charge. On the
other hand, some of the most prominent Liverpool engineers always use
zinc, and take care to apply it most strictly. The evidence of one
of them is as follows: "We always fix slabs of zinc to most boilers,
exposing not less than a surface of one square foot for every twenty
indicated horse-power, and distributed throughout the boiler. This zinc
we find to be in a state of oxide and crumbling away in about three
months. We then renew the whole, and find this will last twelve months
or more, when it is renewed again. Meanwhile we have no pitting and no
corrosion; but on the contrary, the interior surfaces appear to have
taken a coating of oxide of zinc all over, and we have no trouble with
them."


HOW THE MARINE ENGINE MAY BE IMPROVED.

Then the writer considered our present marine engine as to its
efficiency and capability of further improvement. The weight of
machinery, water, and fuel carried for propelling ships has not had due
attention in the general practice of engineers. By the best shipping
authorities the writer is assured that every ton of dead weight capacity
is worth on an average £10 per annum as earning freight. Assuming,
therefore, the weight of the machinery and water of any ordinary vessel
to be 300 tons, and that, by careful design and judicious use of
materials, the engineer can reduce it by 100 tons, without increasing
the cost of working, he makes the vessel worth £1,000 per annum more to
her owners. That there is much room for improvement in this direction is
shown by the following statement, giving, for various classes of ships,
the average weight of machinery, including engines, boilers, water, and
all fittings ready for sea, in pounds, per indicated horse power:

                                       Lb. per I. H. P.

  Merchant steamers.......................... 480
  Royal Navy................................. 300
  Engines specially designed for light draught
    vessels...................................280
  Royal Navy, Polyphemus class (given by Mr.
    Wright).................................. 180
  Modern locomotive.......................... 140
  Torpedo vessels............................. 60

  Ordinary marine boilers, including water... 196
  Locomotive boilers, including water......... 60

The ordinary marine boiler, encumbered as it is by the regulations of
the Board of Trade and of Lloyds' Committee, does not admit of much
reduction in the weight of material or of water carried when working.
The introduction of steel has reduced the weight by about one-tenth; but
it will be the alteration of form to the locomotive, tubulous, or some
other type, combined with some method of forced draught, to which we
must look for such reductions in weight of material and water as will be
of any great commercial value. The engine may be reduced in weight by
reducing its size, and this can only be done by increasing the number of
revolutions per minute.

It has hitherto been the practice to treat the propeller as dependent
upon the size of engines, draught of water, and speed required. This
process should be reversed. The propeller's diameter depends on the
column of water behind necessary to overcome the resistance in front of
it due to the properties of the vessel. This fixed, the speed will then
fix the number of revolutions, which will be found much greater than is
usual in practice, and from this the size of the engines and boilers
will be determined. Great saving in weight can be effected by careful
design and judicious selection and adaptation of materials, also by the
substitution of trussed framing and a proper mode of securing the engine
to the structure of the vessel, as worked out in H.M.S. Nelson, by Mr.
A. C. Kirk, of Glasgow, and in the beautifully designed engines by Mr.
Thornycroft, in place of the massive cast-iron bedplates and columns of
the ordinary engines of commerce. The same may be said of the moving
parts. In fine, the hull and engines should be as much as possible one
structure; rigidity in one place and elasticity in others are the
cause of most of the accidents so costly to the ship-owner; under such
conditions mass and solidity cease to be virtues, and the sooner their
place is taken by careful design, and the use of the smallest weight
of material--of the very best kind for the purpose--consistent with
thorough efficiency, the better for all concerned.


CONSUMPTION OF FUEL IN MARINE ENGINES.

Coming to the question of the consumption of fuel, a considerable saving
has been effected in nine years, as shown in the following table:

               Item.                       1872.       1881.

  Working pressure, lb. per sq. in......... 52.5        77.4
  Heating surface per I. H. P., sq. ft....   4.64        3.919
  Piston speed, feet per min.............. 376         467
  Coal burnt per I. H. P., lb..............  2.11        1.828

This shows a saving equal to 13.38 per cent, in quantity of fuel
consumed. Mr. Marshall then read a letter from Mr. Alfred Holt, of
Liverpool, bearing on this subject, in which Mr. Holt spoke favorably of
the single-crank engine, and stated his belief that the compound system
would ere long be abandoned for the simple engine. He is endeavoring to
feel his way to using the steam in one cylinder only, and so far the
results have been encouraging, and he is now fitting a 2,200-ton vessel
on that system. He is also endeavoring to do without a crank shaft, the
forward end of the screw shaft carrying an ordinary crank with overhung
pin. This experiment also promises satisfactorily. In his opinion the
great improvement of the immediate future is to increase the steam
production of our boilers. A ton weight of a locomotive boiler produces
as much steam as six tons of an ordinary steamboat boiler.

Mr. Holt speaks of the coal account as one of the minor disbursements
of a steamer. He does not give the ratio which coals bear to the total
disbursements, but from other reliable sources Mr. Marshall found that,
according to the direction of the voyage, it varies from 16 to
20 percent.--or, say, an average of 18 per cent.--of the total
disbursements, in a vessel carrying a cargo of 2,500 tons. This will
represent to-day about £3,000 per annum, and in 1872, at equal prices,
the cost would have been £3,750--showing a saving of £750, equal to a
dividend of, say, 3 per cent. on the value of the ship. Again, the cost
of coal per mile run for such a vessel, in 1872, would have been at
least 16½d.; to-day it does not exceed 13d.


EVAPORATIVE EFFICIENCY OF MARINE BOILERS.

The marine boiler as now made is very efficient, but if the quantity of
steam used be considered in relation to the increased pressure, it will
be seen that the boiler of to-day is little if anymore efficient than
that of ten years ago. The present boiler has an evaporative efficiency
of about 75 per cent., and cannot be much improved so long as air
is supplied to the furnace by the natural draught. To increase the
efficiency from 75 to 82.5 per cent. would require about double the
heating surface, the weight of boiler and water being also doubled,
while the gain would be only 10 per cent. Mr. Blechynden's formula, used
in Mr. Marshall's works for weights of cylindrical marine boilers of the
ordinary type, and for pressures varying from 50 lb. to 150 lb., is as
follows:

W = (P + 15) (S + D² L) / C

or W = 2S (P + 15) / C

when S = D² L, which is a common proportion.

  Here W = weight in tons.
       P = working pressure as on gauge.
       S = heating surface, in square feet.
       D = diameter, in feet.
       L = length, in feet.
       C = a constant divisor, depending on the class of
           riveting, etc. For boilers to Lloyds' rules,
           and with iron shells having 75 per cent.
           strength of solid plate, C = 13,200.

This formula, if correct--and it is almost strictly so--would give the
relative weight of boilers per sq. ft. of heating surface, for 105 lb.
and 150 lb. total pressure, assuming we wish to increase the efficiency
10 per cent, as follows:

Weight at 105 lb. = 105 x 1 / C

Weight at 150 lb. = 150 x 1.75 / C = 263 / C

Hence the ratio of weight = 263 / 105 = 2.5

In other words, the boiler with the higher efficiency would weigh two
and a half times that with the lower efficiency. In the case of a vessel
of 3,000 tons, with engines and boilers of 1,500 indicated horse power,
the introduction of locomotive boilers with forced draught would place
at the disposal of the owner 150 tons of cargo space, representing
£1,500 per annum in addition to the present earnings of such a vessel.


MARINE LOCOMOTIVE BOILERS.

Mr. Thornycroft has for some years used the locomotive form of boiler
for his steam launches, working them under an air pressure--produced
by a fan discharging into a close stokehold--of from 1 in. to 6 in. of
water, as may be required. The experiments made gave an evaporation of
7.61 lb. of water from 1 lb. of coal at 212° Fahr., with 2 in. of water
pressure, and 6.41 lb. with 6 in. of pressure. These results are low,
but it is to be remembered that the heating surface is necessarily
small, in order to save weight, and the temperature of the funnel
consequently high, ranging from 1,073° at the first pressure, and 1,444°
at the 6 in. With the ordinary proportions of locomotive practice the
efficiency can be made equal to the best marine boiler when working
under the water pressure usual in locomotives, say from 3 in. to 4 in.,
including funnel draught.

It has fallen to the lot of the writer to fit three vessels recently
with boilers worked under pressure in closed stokeholds. The results,
even under unfavorable conditions, were very satisfactory. The pressure
of air would be represented by 2 in. of water, and the indicated horse
power given out by the engines was 2,800, as against 1,875 when working
by natural draught, or exactly 50 per cent. gain in power developed.

Mr. Marshall then proceeded to refute the arguments which may be urged
against the use of the locomotive boiler at sea, and which we need not
reproduce. Coming to the engines, Mr. Marshall said that the total
working pressure of to-day may be accepted as 105 lb., or equal to seven
atmospheres. If it were boldly accepted that eleven atmospheres, or 165
lb., were to be the standard working pressure, the result would be a
gain of 14.55 per cent., provided no counteracting influence came into
play. Of course, there are forces which war against the attainment of
the full extent of this advantage, viz., the greater condensation in the
cylinders and loss in the receiver or passages.

In regard to the former, it may be questioned whether by steamjacketing
the high pressure cylinder, correctly proportioning the steam passages,
and giving a due amount of compression in both cylinders, this may not
be reduced far below the generally received notion; and the latter cause
of loss may be considerably reduced in its effect by a more carefully
chosen cylinder ratio. The ratio usually adopted, between 3.5 and 4 to
1, whether the pressure be 70 lb. or 90 lb., may well be questioned.
With a cylinder ratio of 2.95 to 1, the economic performance is very
good, and equal to any with the higher ratio. A lower cylinder ratio has
another advantage of considerable value, viz., that the working pressure
can be much reduced as the boilers get older, while by giving a greater
amount of steam the power may be maintained--at an extra cost of steam,
of course, but not so great a cost as with higher ratios. The cut-off
in the high-pressure cylinder usually takes place at about 0.6, and
the ratio of expansion has decided the ratio of cylinders. The use of
separate starting valves in both cylinders obviates that necessity.

The difficulties in the way of taking advantage of the higher economic
properties of greater pressures than hitherto used on board ship, are,
it is submitted, not insuperable, and it would be to the interest of all
that they should be firmly and determinedly met. It may be accepted as
an average result that the Woolf engine, as usually arranged, will use
10 per cent. more steam than the receiver engine for the same power.

Of the three-cylinder receiver type the data are insufficient to form a
definite opinion upon; but so far the general working of the Arizona is
stated to be as good, economically, as any of the two-cylinder receiver
class. The surface condenser remains as it was ten years ago, with
scarcely a detail altered. In most engines it remains a portion of the
framing, and as such adds greatly to the weight of the engine.

It is a question seriously worth consideration whether or no the surface
of tubes can be reduced. The practice at present is to make the surface
one-half the boiler surface as a minimum, that is, equal to about 2
square feet per indicated horse power. In practice, the writer has found
1.4 square feet per indicated horse power to maintain a steady vacuum of
27½ inches.

Mr. Marshall has just completed six pairs of engines for three twin
screw ships, having steel shafts of 10 inches diameter, and has in each
case run the engines at 120 revolutions per minute, while indicating
1,380 horse power from each pair for ten to fifteen hours without
stopping; and in no case has a single bearing or crank pin warmed or
had water applied, the surfaces on examination being perfect. In these
engines all working bolts, pins, and rods, except the piston and
connecting rods, are of steel, all rods in tension being loaded to 8,000
lb. per square inch. The boilers are of the Navy type, made throughout
of Siemens-Martin steel plates, riveted with steel rivets, all holes
drilled. Furnaces are welded and flanged; the tubes are of brass. In
comparison with an ordinary merchant steamer's iron boilers of the
double ended type, they weigh, including water and all appurtenances, as
follows:

                      Double ended Type.    Navy Type.

  Weight, tons............   135 ...........  146
  I. H. P................. 1,400 .......... 2,760
  Draught................ Natural ......... Forced.


SCREW PROPELLERS.

The screw propeller is still to a great extent an unsolved problem. We
have no definite rule by which we can fix the most important factor of
the whole, namely, the diameter. Mr. Froude has pointed out that by
reducing the diameter, and thus the peripheral friction, we can increase
the efficiency; and this is confirmed by cases--of Iris reduced 2 feet
3 inches, and the Arizona reduced 2 feet. This must, of course, be
qualified by other considerations. The ship has by her form a definite
resistance, and a certain speed is required; if the propeller be made
too small in diameter, the ship will not be driven at the required
speed, except at serious loss in other directions. This question was too
large and complicated to be dealt with here, and should, in the first
instance, be made the subject of careful and extended experiment, on
which a separate paper should be written.

To sum up the whole. Progress has been made during the past nine years,
and in the following particulars:

1. The power of the engines made and making show a great increase. 2.
Speeds hitherto unattainable are now seen to be possible in vessels of
all the various classes. 3. The consumption of fuel is reduced by 13.38
per cent. on the average; and numbers of vessels are now working on much
less coal than that average, while the quality of the coal is in nearly
all cases very inferior, so that it is not unfair to take credit for
20 per cent. reduction. 4. The working pressures of steam are much
increased on the average, and are still increasing; many steamers now
being built for 120 lb. per square inch, while 90 lb. is the standard
pressure now required.

       *       *       *       *       *




STEAM FERRY BOATS OF THE PORT OF MARSEILLES.


The small steam ferry boats represented in the accompanying cut are
doing service in the port of Marseilles, and the following description
of them has been given by Mr. Flecher in the _Bulletin de la Société des
Anciens Elèves d'Arts et Metiers_:

All those who are acquainted with the Old Port of Marseilles know the
inconvenience of communication between one shore and the other, and the
high price of ferriage by row boats. To obviate this, Captain Advient
has been struck with the happy idea of creating a cheap steam service
(fare one cent), thus supplying a genuine want in the modes of
locomotion of the city.

The building of these ferry boats, on a system providing for the use of
separate hulls, was confided to Messrs. Stapfer, De Duclos & Co., of
Marseilles, whose well-known reputation was a sufficient guarantee that
the problem would be successfully solved.

There existed difficulties of two natures: The first of these related to
the stability of boats such as this, having their engine, boiler, supply
of coal, forty passengers who might all occupy one side of the vessel, a
central superstructure, with roof; and, finally, all the weight centered
on five feet of the deck, with nothing below to counterbalance it except
the hollow hulls and two three-foot compartments, each placed toward the
central portion of the hulls and designed as fresh-water reservoirs
for the steam generator. The second difficulty was to obtain the best
utilization possible of a screw placed in the current between the hulls
and upon a shaft inclined toward the stern, that is, "stern" by analogy,
for there is no distinction of fore and aft in ferry boats.

[Illustration: STEAM FERRYBOATS OF THE PORT OF MARSEILLES.]

The conditions of the problem were finally fulfilled to the satisfaction
of all concerned, and especially to that of the public.

The hulls, navicular in form and having a flat bottom, are constructed
of one-tenth inch iron plate and 40x40 angle iron. Their dimensions
are: Length, 33 feet; breadth, 3¼ feet; and depth, 5 feet. The internal
distance between the two shells is 7¼ feet. These hulls, having
absolutely water-tight decks, are connected below by tie bars of flat
iron, and above by vertical stays 1 foot in length, which serve to
support the floor-planks of the deck and boilerplate flooring of the
engine-room. The engine-room, which is 19½ feet long by 5 feet wide, is
constructed of varnished pitch-pine, with movable side-shutters of teak.
The roof, of thin iron plate, is provided with a ventilator to allow of
the escape of hot air.

The passengers, to the number of forty or fifty, can move about freely
from larboard to starboard, or from stem to stern, or seat themselves
on the benches running along the inside of the guard railing on the two
sides of the vessel. They are protected from rain by a roof, and from
the rays of the sun by a curtain extending along the sides.

Although the usual method of landing is fore and aft, gangways have been
provided at the sides for side-landing should it become necessary.

The general appearance of one of these boats may be likened to that of a
floating street-car. Finally, a small apartment, provided with benches,
is provided for the use of those passengers who might be taken sick, or
for office purposes, if need be.

The total weight of one of the boats is divided up as follows:

  Forty passengers................ 6,200 pounds,
  Engine and boiler............... 6,600   "
  Ballast, water, and equipment... 9,900   "
  Deck and superstructure......... 6,600   "
  Hull and accessories............12,500   "
                                  ______

  Total...........................41,800   "

or a displacement of about 700 cubic feet, corresponding to a maximum
draught of 3.7 feet. The mean speed is 4 knots, or 4½ miles per hour, a
great velocity being unnecessary, owing to the small distance to cross
in a port often obstructed by the general movement of vessels taking
place therein.

The engine is from 16 to 18 horse-power. Its frame is inclined
perpendicularly to the direction of the screw-shaft, the extremity of
which is supported near the screw by a strengthened cross-stay serving
as a pillow-block. The cylinder is 8 inches in diameter, and the piston
has a stroke of 6 inches, causing the screw (which is 3¼ feet diameter)
to make 200 revolutions per minute. The screw, although it has a wide
surface of thrust, gives, nevertheless, a recoil of about 30 per cent.,
because of its location between the hulls and its oblique action on the
shaft.

The steam is furnished by a tubular boiler having an internal fireplace
and a heating surface of sixteen square meters, the draught being
effected by the exhaust of the engine. This boiler, which is tested
up to 14 pounds, is fed by a steam pump, or by a pump actuated by the
engine. The feed pumps take water successively from one or the other of
the reservoirs in the hulls. The reservoirs are filled in the morning,
and their level is ascertained by two small and ingenious Decondun
indicators, the dials of which are placed against the walls of the
engine-room.

Taken altogether, these little boats are well arranged and quite
handsome; and, since they were put into service in June, 1880, they have
proved a great convenience to the hard-working and active population for
which they were built.

       *       *       *       *       *




OPENING OF A NEW ENGLISH DOCK.


In July last, Admiral the Duke of Edinburgh, with the Naval Reserve
Squadron under his command, arrived in the Firth of Forth and anchored
in Leith Roads. His Royal Highness performed the ceremony of opening the
new dock at Leith, which has been named after him. The "Edinburgh" Dock
at Leith, which was commenced in 1874, consists of a center basin 500
ft. long and 650 ft. wide, and two basins 1,000 ft. long and 200 ft.
wide, separated by a jetty having a width of 250 ft. The total amount
of masonry in the wet docks is 100,000 cubic yards. The north and south
quays are each 1,500 ft. long, and the two sides of the jetty 1,000 ft.
long each, having a total quayage in connection with the dock of 6,775
ft. The walls are 15 ft. thick at the base, narrowing in two tiers to
8 ft. The new dock will cost altogether about £300,000. Leith now
possesses five docks and a total quayage of three miles 808 yards, 1,234
yards of which is the old portion. These works have been constructed, at
a cost of nearly one million sterling, by the Leith Dock Commissioners,
whose chairman, Mr. James Currie, presented an address to the Duke of
Edinburgh, on board the flag-ship H.M.S. Hercules, giving an account of
their affairs. The other docks at Leith are named the "Old Dock," the
"Queen's Dock," the "Victoria," the "Albert," and the "Prince of Wales
Dock." The opening ceremony was arranged to consist of the steamer
Berlin, with his Royal Highness and the Dock Commissioners on board,
accompanied by Sir Donald Currie, M.P., and other gentlemen, passing
through the entrance from the Albert Dock to the new dock, across which
a blue ribbon had been stretched. At the moment when the ribbon snapped
asunder, under the bow of the Berlin, the Duke of Edinburgh, stepping
forward on the upper deck of the steamer, said, "I have now the
gratification of declaring this dock open, and calling it the Edinburgh
Dock." On this announcement being made, a signal was conveyed to a
battery of guns, posted on the sea wall of the new dock, from which a
party of the Royal Artillery fired a Royal salute. The steamer, having
gone round the new dock, was brought up at the quay at the west. His
Royal Highness the Duke of Edinburgh, with Prince Henry of Prussia, the
officers of the fleet, and the Commissioners, disembarked and proceeded
to the saloon in the new dock, where luncheon in honor of the occasion
was given by the Leith Dock Commissioners.--_Illustrated London News,
Aug. 6._

[Illustration: OPENING OF A NEW ENGLISH DOCK.]

       *       *       *       *       *




IMPROVED GRAIN ELEVATOR.


The illustration shows the apparatus at work transferring a cargo of
grain from the hold of a ship by means of an elevating band fitted
with buckets. By a simple contrivance shown in the engraving by
diamond-shaped squares, the elevating band can be shortened or
lengthened at pleasure, so as to suit it to the position the grain to be
elevated occupies in the ship or barge. When the grain is elevated to
the point whence it is to be transferred to the granary, railway
truck, or other destination, the band travels horizontally on suitable
bearings, the buckets being so constructed that in traveling they retain
their load intact. The contrivance for lengthening and shortening the
bucket band is an application of the "lazytongs" device, which is well
known. The float of the elevator is shown at the left hand of the
engraving, and, as seen in the latter, there is an automatic weighing
machine, by which the material may be weighed as it is delivered, before
it goes to the bottom of the elevator, to be again transferred by its
means to the barge or granary. Simplicity, efficiency, and adaptability
to any position in which elevators of this class are desirable, are the
claims the patentees, Messrs. Behrns & Unruth, Lubeck, make for the
advantages of their apparatus.--_London Miller_.

[Illustration: IMPROVED FLOATING ELEVATOR.]

       *       *       *       *       *




IMPROVED DREDGER.


We illustrate below a useful type of dredger made by Messrs. Rennie, of
Blackfriars, England. The drawing almost explains itself. The machine
consists of a double barge or pontoon, in which is erected a derrick.
This derrick works a "spoon" dredge at the end of a lever. The spoon, as
shown, is at its lowest position. It will make a forward stroke, through
about one-sixth of a revolution, and will thus become filled with
mud and be lifted above the surface of the water. The motion will be
imparted to it by the chain and pulleys seen at outer end of the derrick
jib. The jib will then be swung round over the bank on a hopper barge
and its contents delivered. The requisite power is supplied by the steam
engine at the end of the pontoon. Messrs. Rennie have made several of
these little dredgers, which are found very useful and handy in shallow
water.--_The Engineer_.

[Illustration: SINGLE BUCKET DIPPER DREDGER.]

       *       *       *       *       *




RAILWAY ALARM WHISTLE.


In order to prevent a train passing a danger signal during a fog or
snowstorm without being seen by the engineer, the Southern Railway
Company of France have attached to the locomotive a steam whistle, which
is controlled by the signal. The whistle is connected with an insulated
metallic brush placed under the engine. Between the rails there is a
projecting contact bar, faced with copper, which is swept by the brush
when the train passes. This contact piece is connected with the
positive pole of a voltaic battery, the negative pole of which is in
communication with a commutator on the signal post, from which a wire
leads to the ground. When the signal is "line clear" the passage of the
brush over the fixed contact produces no result; but when the signal
marks "danger," the commutator brings the negative pole of the battery
in direct communication with the ground, and when the brush passes over
the contact the completion of the electric current causes the whistle to
be sounded, so as to alarm the driver.--_L'Ingen. Univ._

       *       *       *       *       *




FURNACE FOR THE MANUFACTURE OF SULPHIDE OF CARBON.


Sulphide of carbon (CS_2) is prepared by passing the vapors of sulphur
over charcoal heated to redness. In laboratories, charcoal and roll
brimstone are employed so as to obtain as pure a product as possible;
but sulphide of carbon having now become so important a commercial
product, and being employed for so large a number of industrial
purposes, it has been found more economical to substitute coke for
charcoal and pyrites for brimstone.

The Messrs. Labois, in their system of furnace represented herewith,
have had in view the manufacture of this product under as economical
conditions as possible, by coupling over two connected fireplaces the
retort in which the pyrites is distilled, and that in which the reaction
of the sulphur and carbon takes place.

The pyrites is fed from the hopper, A, into a distributing box, B,
furnished with a valve which is maneuvered by a lever. From thence it
descends into the retort, G, where it is roasted by the heat of the
fireplace, L. The sulphur converted into a state of vapor passes through
the conduit, R, into the coke or charcoal retort, G', which is divided
into two parts by the partition, _g g'_, of refractory clay, and heated
by the fireplace, L'.

[Illustration: LABOIS'S SULPHIDE OF CARBON FURNACE.]

The conduit, R', leads the sulphide of carbon in a state of vapor to the
condensing apparatus. The uncombined sulphur which is carried along is
deposited in the first part of the retort by the arrangement of the
partition, which permits of passage only below. The registers, V and
V', permit of the introduction of the sulphur vapor and the exit of the
sulphide of carbon being regulated.

The apparatus is so easy of installation that it may be applied without
much expense to pyrites furnaces already in operation.

Wherever a manufactory of the product is to be started, the system
recommends itself by its simplicity, and by the facility with which the
operation may be watched and conducted.

       *       *       *       *       *




BROUARDEL'S DRY INSCRIBING MANOMETER.


Brouardel's manometer, represented herewith, is designed for showing
graphically variations in the pressure of gas, either at the works
during the course of manufacture, or at any point whatever in the system
of piping.

For this purpose water manometers have hitherto been employed; but,
although the indications given by these are very accurate, their form
and weight are such as to render them not easily transportable; and
then, again, considerable care is necessary in putting them in place.

Mr. Brouardel's registering manometer does not give so accurate
indications, perhaps, but it possesses, as an offset, the merit of being
very portable and easily put in place; and, besides, it inscribes the
hour at which the pressure is exerted.

The apparatus consists of a metallic cylinder, A B, which carries a
circular shoulder, C, that rests on a plate, D--the latter being put in
motion by a clock which is wound up by means of a button under the base,
E, of the apparatus. The two standards, F F, carry a crosspiece which
supports a disk that closes freely the aperture of the drum, A B, in
such a manner as not to impede its rotation.

In the interior of the cylinder there is a metallic cup which is
connected with the central reservoir by an impermeable membrane, I.
These three parts form a closed chamber, into which the pressure comes
through a tube, F, provided with a cock. A spring, M, which counteracts
the pressure, is arranged between the crosspiece, G, and the bottom of
the reservoir. The latter carries also a small rod, K, which is provided
with a cord made of braided silk. This cord runs over a pulley, N, whose
axle carries at its other end a still larger pulley, O. Toward the
middle of the latter is fixed a silken cord which hangs down on each
side, after making several turns around the pulley. To the front cord
is attached a slide, Q, moving in a vertical direction, and to which is
fixed an inscribing style, R. The other extremity of the thread enters
the hollow upright, and carries a weight which is greater than the
combined weights of the slide, the membrane, and the internal reservoir.
The upright serves as a guide to this counterpoise.

In order to use the apparatus there is affixed to the cylinder, A B, a
sheet of paper divided in a vertical direction into as many parts as
the cylinder takes hours to make one revolution. The divisions running
horizontally represent centimeters of water or of mercury, according to
the strength of the spring, M, which should be so constructed as to be
in relation with the pressure. The operation of the apparatus may be
readily understood.

[Illustration: GAS INDICATOR OF MANOMETER.]

When the gas reaches the pressure chamber, the spring, M, contracts, and
consequently the counterpoise descends, and causes the cord, O, which
carries the slide and writing style, to wind around the pulley. When the
pressure diminishes, the movement takes place in an opposite direction.

The tracing is done by means of a special form of style giving indelible
curves through the medium of colored glycerine. The position of the
point is determined in such a way as to annul the friction of the pen,
and consequently to give it greater sensitiveness.

It should be remarked that the course of the rod, K, is amplified in the
tracing of the ordinates of the pressure according to the ratio of the
diameters of the pulleys, N and O.

The apparatus may be carried by hand by means of the handle, S, either
in or out of its case. To put it in operation, it is only necessary to
connect the apparatus with a gas burner (located near the place where
the variations of pressure are to be observed) by means of rubber
tubing. The apparatus may be employed under the same circumstances as
glass and U-shaped water manometers, with the further advantage that the
results are registered, and consequently can be more easily compared.

       *       *       *       *       *




CENTRIFUGAL APPARATUS FOR CASTING METALS.


The apparatus represented in Figs. 1, 2, 3, and 4 is the invention of
Messrs. Taylor & Wailes, and is designed for casting metallic objects
in annular form, its arrangement being slightly varied according to the
nature of the objects to be cast. In all cases where a special form is
to be given to the outer or inner circumference of the object, or where
it is desired to exert a pressure on the circumference, such form or
pressure is obtained by the introduction of a core which may be expanded
or contracted as need may be. For this purpose an expansible, metallic
core is employed, the arrangement of which is shown in Figs. 1 and 2,
and which is so fashioned that the inner circumference of the ring to be
cast may receive the desired form. This core is formed of the pieces, g,
g', made of cast-iron or any other material which fuses with difficulty,
and which are placed in the revolving mould in such a way that after the
cooling of the pieces the parts, g, recede by the shrinkage of the piece
and thus free the core. The parts, g, of the core are in the shape of
circular segments, and are united at their external circumference by a
flange, along with which they form a shoulder piece for the casting.
As a consequence of the rapid revolution of the mould, these parts are
pressed by centrifugal force against the molten metal which is run into
the mould.

[Illustration: CENTRIFUGAL METAL MOULDING APPARATUS.]

The plan, Fig. 2, shows the arrangement of the parts, g, g', and allows
it to be seen that the pieces, g', act as wedges against the segments,
g, and push these out so as to form a perfect circle. The molten metal
cannot become oxidized in the mould, since it is shut off from contact
with the external air by the cap, C, which covers it. Oxidation may,
however, be further prevented by passing some deoxidizing or neutral gas
into the mould. For this purpose the mould is filled before the casting
is done with some such gas as illuminating gas, carbonic acid, nitrogen,
or hydrogen.

This improved process of casting may also be employed for objects which
do not possess an exactly annular section. The moulds are then arranged
eccentrically in a frame which is made to revolve rapidly during the
cooling of the metal In this way the pieces are less strongly compressed
at the places where they are nearest the center of rotation than a the
points where the radius is greater.

Figs. 3 and 4 show section and plan of an apparatus of this kind. The
sand moulds are arranged in the frame, a b which revolves about the
axle, c. In the moulds there are iron cores, h, which press the metal
during rotation and thereby produce compact pieces.

       *       *       *       *       *




APPARATUS FOR THE MANUFACTURE OF WOOD PULP.


For manufacturing wood pulp Mr. Dresel employs an apparatus such as
represented in Figs. 1 and 2, consisting of an upright cylindrical
reservoir, A, supported on a frame by means of trunnions, z. This
reservoir, which is of boiler plate, is furnished with a cover, D, which
has in its center a piece of tubing, with stop-cock, C. A series of
tubes, R, whose diameter and length are proportioned to the volume of
the boiler, A, is filled with the liquid which is contained in the
boiler, so as always to be able to rapidly produce a pressure of nine
atmospheres or more by direct heating. The flanges of the tubing are
provided with a cut-off of angle iron identical with that of the tube,
D. By means of this arrangement the cocks and the flanges, E, permit of
communication between the serpentine tubing, R, and the boiler being
interrupted; while the heat developed by the fire-place, F, causes an
active circulation in both the tubing and boiler.

[Illustration: DRESEL'S WOOD PULP APPARATUS. Fig. 1]

[Illustration: DRESEL'S WOOD PULP APPARATUS. Fig. 2]

To put the apparatus in operation the cover, D, is first unscrewed, and
there is put into the boiler a certain quantity of wood, which has been
divided up by a cutting machine of special form. Then the boiler is
filled to the proper height with the liquid necessary to dissolve the
incrusting materials, the cocks, B, being closed. Afterwards there
is fixed immediately beneath the angle-iron ring of the cover, D, a
perforated iron plate upon which the contents of the boiler rest when
the latter is turned up. Then the cover is fastened down and the boiler
is put in communication with the heating apparatus. The cocks, E and B,
are opened, so that the liquid may begin its movement in the tube, a,
the boiler, A, and the tube, n. As soon as the proper temperature
is reached for converting the wood into fiber and decomposing the
incrusting matters, the heat is shut off in case the tubing, R, is not
connected with another like boiler, and, after closing the cocks, E and
B, and shut off communication between the tubing and the boiler, the
latter is turned over and the cock, C, gradually opened in order to
allow the steam to escape. When the temperature has descended to 100°
in the boiler the cover, D, may be opened, after the liquid has been
allowed to flow out through the cock, C. Next, lixiviation is effected
by connecting the cock, C, with the steam pipe, P, and causing steam
under pressure to enter the boiler, A. The action of the steam on the
contents of the latter, which are now converted into cellulose, mixed
with a large quantity of dissolved matters and of liquid, effects a
complete washing and permits of the recovery of considerable quantities
of useful chemical products. Moreover, the steam purifies, decolorizes,
and completely separates the fibers, and renders them more easily
susceptible of being bleached. Finally, the perforated bottom, S (which
is formed of two parts), is removed and the boiler emptied.

In order to have the operations under control, and for the purpose of
safety, there is riveted into the boiler, A, a tube, T, containing a
thermometer: and there is fixed to the tube, a, a pressure-gauge, M, and
a safety-valve. The level of the liquid is ascertained by means of a
gauge-cock, H.

       *       *       *       *       *




RECENT PROGRESS OF INDUSTRIAL SCIENCE.


The thirty-fourth annual summer meeting of the Institution of Mechanical
Engineers began on Aug. 2, at Newcastle-on-Tyne. The following is an
abstract from the address of the president, Mr. E. A. Cowper.

He began by stating that as members of the Institution of Mechanical
Engineers, on revisiting their brother members and friends here in
Newcastle, after an interval of twelve years, they came as it were to
one of their natural homes; certainly to the home of one of the greatest
engineers that England has ever produced, and the birthplace of the
locomotive, which has done more than any other improvement, of our age
to lessen the cost of materials to the men who have to use them, and
therefore to cheapen and extend production in the most wonderful manner.
He then went on to say that it seems but a few years ago since George
Stephenson, at a meeting in 1847, proposed the resolution that the
Institution of Mechanical Engineers be formed. He was strongly supported
by a large number of the mechanical engineers of the country, and the
speaker had the honor of seconding the resolution that he be first
president. The intention was that engineers from all parts of the
country should join to form a compact body capable of discussing
and judging of all mechanical subjects and appliances. In this the
institution had been eminently successful, and it numbered among its
members mechanical engineers in every large town in the country, and has
increased in strength and importance.

The last twelve years have been marked by many very important
changes, while low prices have generally ruled. Among other causes of
fluctuations in demand and supply (and consequently in values) must be
mentioned the occurrence and the threatening of foreign wars, which
disturbed the course of commerce greatly for some years. Such causes
must be considered as extraneous to the sphere of influence possessed by
good or bad manufacturing or engineering. Mr. Cowper does not look upon
the very great expense of improved war material and implements as an
unmixed evil for this country; for it so happens that we can better meet
such outlay than any other nation, and thus our wealth gives rise to
greater power and security than our neighbors possess; while, seeing
that we are not an aggressive nation, such power tends materially at
once to the progress of this country, and to the peace of the world.
Having referred briefly to one cause of disturbance to the progress of
mechanical engineering, he named another, which at the present moment is
occupying thoughtful men to a considerable extent, namely, the arbitrary
imposition of duties and bounties for the professed object of protecting
manufactures, while in fact they constitute taxes on a nation for the
benefit of a few individuals. In some countries excessive duties have
been imposed, as against our manufactures, and it is even proposed to
increase them; while in other cases bounties are actually paid out of
the public purse to men engaged in a particular manufacture, on their
exporting to this county certain of their wares, as, for instance,
beet-root sugar.

One extremely significant lesson, resulting from high duties--which it
may be hoped will not be thrown away upon the American public--is, that
whereas our cousins on the other side of the water used to build almost
all the American "liners" of wood, they now find that, with their
excessive duties against the importation of iron and steel from England,
they cannot compete with English iron and steel ship-builders and marine
engineers. This is one of those damaging effects naturally produced
by excessive protective duties; which, while they enable American
ironmasters quickly to realize enormous fortunes, drive the American
merchants to purchase English ships, or intrust their merchandise in
English bottoms, as it is impossible to maintain protective duties at
sea.

Whatever fluctuations have occurred, it is now pretty clear that
several foreign nations have settled down to cultivate and extend their
manufactures, and we are brought face to face with the fact--which has
now been for some years growing to its present importance--that many
articles which in years gone by we thought it to be our especial
province to supply, are now produced in the very countries requiring
them. Even Spain is awakening to the advantage of producing hematite
iron from her own excellent ores, with English and Welsh coke carried
out in the same ships that bring Spanish ores to this country.

Now with regard to the possibility of any foreign nation eclipsing us in
our manufactures, he would say at once that any such successful rivalry
on their part is far worse than the effect of any duties, even if they
be prohibitive; for it means rivalry in the markets of the world, and
possibly in our own markets here at home. Therefore it behooves us
to put our house in order, and see in what way we may be enabled to
manufacture better and with greater economy. Mechanical engineering is
of such extreme importance in advancing civilization, that it is most
essential that its progress should be rapid and unimpeded.

Perhaps the very large increase in steam shipping, and the change from
sailing ships and paddle steamers to screw steamers, has been one of the
greatest improvements of recent times, and it is none the less real
or important from having been gradual, while the result to this
neighborhood has been most beneficial. This change has been due in great
measure to the introduction of very economical marine engines, chiefly
of the compound type, together with better boilers carrying a higher
pressure.

The speed and regularity of ocean steamers has also greatly improved,
and one small scientific improvement has added much to the safety of
traversing such seas as the Atlantic at a high speed--namely, the
careful and continual use of a good thermometer, to ascertain constantly
the temperature of the sea-water at the surface. For if an iceberg is
floating within a quarter of a mile--or even half a mile, if the sea is
pretty smooth--the surface water will be several degrees colder than the
rest of the sea; since the very cold fresh water, resulting from the
melting iceberg, floats on the top of the sea water for some distance.

No doubt the use of iron, and now of steel, has contributed most largely
to the increase of shipbuilding in this country. Good arrangements
of water ballast have also proved very useful; and steam cranes and
arrangements for loading and discharging cargo have greatly promoted the
use of steam colliers, enabling them to make more voyages in the year.

Closely connected with marine engineering is the great improvement in
the economy of stationary engines, which has become more fully developed
during recent years, both in reference to waterworks engines and factory
engines. In aid of stationary engines, "surface evaporator condensers"
have been found very useful, particularly where the supply of water is
very limited; and at waterworks it is now very common to pass the whole
water pumped through a surface condenser, thus giving a good vacuum
without the expenditure of any water, and with the result of only
raising the temperature of the water a very few degrees, on account of
its large volume.

Locomotives have shared to some extent in the general improvement in
machinery. The boilers are better made, and are safer at the higher
pressures now carried than they were formerly with a low pressure.
Several new valve gears of great promise have been brought forward, both
for locomotives and marine engines. Among them Joy's motion should be
again noticed. Mr. Webb says: "The engine shown at Barrow has been at
continuous work ever since the Barrow meeting, and has run 30,278 miles;
we had it in for examination on the 18th inst., and found the motion
practically as good as the day it went out of the shop, more especially
the slides, about which so many of the people who spoke at the meeting
seemed to have doubts. I do not think you could get a visiting card
between the slides and the blocks; in fact, the engine has been sent out
to work again, having had nothing whatever done to it. The first thing,
of course, that will require doing will be the tires; as far as I can
see nothing else will want doing for some time."

A very fine engineering work has now been accomplished in America in
reference to navigation, namely, the deepening of the channel at the
mouth of the Mississippi through the training of the river by jetties
and banks. In consequence, ships of large size may now go up the
river--there being plenty of deep water above the mouth--and bring down
grain cargoes, without the expense and inconvenience of transshipment,
thus reducing the freight of corn to this country. This great
improvement is the work of Captain Eads. A somewhat similar improvement
was the blowing up of about 50,000 tons of rock from the bed of the
river at the narrow pass of Hell Gate, near New York. It is to be hoped
that these good examples may spur on our friends on the Continent to
improve their harbors, so that large channel boats may cross with
comfort to the passengers, thus avoiding the excessive expense that a
tunnel would involve.

Great improvements have been made in the illumination of lighthouses
by oil lamps; a light equal to 1,300 candles has been produced by Mr.
Douglass, of the Trinity House, and now two such lights will be placed
one above the other, where required. The electric light has made such
numerous and rapid strides that it is impossible even to notice its
various applications; but on the one hand the lighting by Dr. Siemens
of four miles of dock frontage at the Albert Dock of the London and St.
Katherine Dock Company, together with the railway behind the warehouses,
and the warehouses and ships themselves, and, on the other hand, the
elegant and steady domestic light of Mr. Swan, are excellent examples
of the two extremes in this department. I believe we shall have the
pleasure of closely observing the Swan light during our visit here. The
lighthouse electric light is also a noble application of the great power
of a single electric light on the arc principle. The most powerful
electric light in the world is situated near here on the coast, between
the Tyne and the Wear. It is possible, and even probable, that one of
the great uses to which electric force will be applied eventually, will
be simple conveyance of power by means of large wires; and as a higher
percentage of power is gradually being realized, this method will become
more economical. I may mention that 60 per cent. has already been
obtained.

The invention of Messrs. Thomas & Gilchrist, by which a very large field
of ironstone is now, for the first time, made available for the purpose
of making good steel by the Bessemer process, bids fair to make very
considerable alterations in the steel-making trade, and in the hands
of Mr. E. Windsor Richards it has been made a great success, while in
Germany there are several works also using the process largely. Mild
steel is now being used to a great extent for the construction of steam
boilers as well as of ships, and in steel castings for a variety of
purposes, such as spur wheels, frames of portable engines, manhole door
frames, etc., etc. Among the uses to which steel may be put is the
manufacture of steel sleepers in place of wood. It is a very encouraging
fact that there are now, or rather there were already, at Dusseldorf, in
1880, 70,000 tons of iron or steel railway sleepers in use in Germany.
Mr. Webb, of Crewe, has exhibited a very promising arrangement of
sleepers and fastenings, to be made either of iron or steel. Steel
sleepers should also be used for tramways.

If, now, some clever ironmaster could only accomplish the task of making
a good "street pavement" of cast iron, the increased demand for pig
metal would be enormous. It has nearly been accomplished already, by
several different modes of construction; and there are very many streets
where the luxury of wood pavement, which wears very rapidly, cannot be
afforded, and where macadamizing will not stand the wear and tear of the
heavy traffic. The use of ingot steel, or very mild steel, for making
tin-plates is now an established thing, and manufacturers are now taking
this metal for making large tinned sheets up to seven by three feet.

The making of casks by machinery, cheaper and better than those made by
hand, is now an accomplished fact by Mr. Ransome's machines. There are
twelve factories already established abroad, some turning out 2,000 or
3,000 casks a week. This is a good case of English invention taking the
lead in a manufacture.

Among good mechanical appliances that have been proved to be highly
valuable to the civil engineer may be mentioned the excavating machine,
which answers well for certain soils and situations, though not for all;
and the dredger of Messrs. Bruce & Batho, for excavating from the inside
of piers in water.

In manufacturing chemistry, which, with its numerous mechanical
appliances, is much indebted to mechanical science and engineering,
great advances have been made during the last dozen or twenty years.
Aluminum has been brought into practical use to a large extent, it
being at once a very light metal and a very cleanly one. "Anthracine,"
obtained from coal tar, has been manufactured largely for the purpose of
producing the various brilliant dyes now so common.

New materials for making candles have been manufactured, in some cases
by purely mechanical means, such as boiling together for some hours, at
a pressure of several hundred pounds per square inch, neutral grease and
water, when the water takes up the base, viz., glycerine, and leaves
the grease as an acid grease. This same effect has been noticed in some
steam boilers, where the same water, without admixture of fresh, has
been used over and over again with surface condensers. Then, again,
large rotating chemical furnaces have been introduced; and improved
glass furnaces--particularly tank glass furnaces, in which the batch is
put in at one end, and the working holes are toward the other end--have
cheapened the actual production of glass, and are being worked largely
on the Continent, and to some extent in this neighborhood. Toughened
glass has made some progress for certain purposes. Besides the improved
and extended use of glass in lighthouse illumination, it has again
been pressed into our service for other purposes, through our greatly
extended knowledge of the laws of optics.

Spectrum analysis has become of practical use, and photographs of the
various Fraunhofer lines in the spectrum have been taken as permanent
records of each experiment. That such extended knowledge should have
been developed by that one little instrument, the lens, is but natural;
for the lens is at once the means by which we discover the extreme
magnitude of some portion of the infinite works of the Almighty in the
architecture of the heavens, and by which we appreciate to some extent
the extremely minute markings of a diatom that one cannot see with the
naked eye. At the same time we feel sure that there are other markings
still smaller, as every increase in the power of the microscope has
always rendered visible some markings still smaller than the last;
and in like manner has every increase in the power of the telescope
developed more worlds and suns far away from our system and beyond our
Milky Way. An approach to the infinite in minuteness and to the infinite
in magnitude and distance is thus furnished to us by one instrument
alone.

There was but one further observation that he would venture to make, and
it is this.

When one looks back upon the goodly list of clever men and benefactors
of the human race, who have lived, say, during the last hundred years,
one is sometimes tempted to wish that more of those scientific men, who
have had the most brilliant ideas, and been our greatest discoverers,
should have striven to carry out their discoveries into practice. For
instance, take Faraday's beautiful discoveries in electricity. It was,
in a manner, left to Sir Francis Ronalds, Professor Daniell, Professor
Wheatstone, Fothergill Cooke, Dr. Siemens, and others, to develop from
those discoveries the "intelligence wires," and "bands," that now
encircle the earth, and unite nations, and do so much to prevent
misunderstandings.

It is gratifying to know that the engineering profession has not been
forgotten when honors have been conferred on distinguished men; and
among others may be named Sir William Fairbairn, Sir John Rennie, Sir
Peter Fairbairn, Sir Charles Fox, Sir William Armstrong, Sir Joseph
Whitworth, Sir John Hawkshaw, Sir John Coode, Sir William Thomson, Sir
Joseph Bazalgette, Sir Charles Hartley, Sir Charles Bright, Sir James
Ramsden, Sir John Anderson, Sir George Elliot, Sir Daniel Gooch, Sir
Henry Tyler, Sir Samuel Canning, Sir Edward Reed, and Sir Frederick
Bramwell. With many noble examples before us, and with signs of an
improvement in many branches of commerce, he trusted that the latter
part of the present century will, with somewhat greater exertion of
thought and enterprise on our parts, be marked, not only by numerous
small improvements, but by many substantial inventions for the good of
mankind.

       *       *       *       *       *




THE HOBOKEN DRAINAGE PROBLEM.


Our thriving neighbor, Hoboken, just across the Hudson River, has a
large and vitally important problem to solve. Of the 720 acres within
the city limits, 270 acres lie at a considerable height above the river
and constitute what are known as the knoll or uplands of Hoboken.
Between this low ridge and Palisade Ridge lie 450 acres of marsh lands
or meadows, 140 acres of which have already been built upon. The marsh
is about half a mile wide, and something like a mile and a half long,
extending southward into Jersey City. The surface is a network of matted
vegetation and roots perhaps five feet deep, and under that lies a mass
of blue clay or river silt 100 feet or more in depth. The original
tidal flow over these marsh lands has been obstructed by viaducts for
railroads and streets, leaving only two natural outlets, a sluice way at
Fifteenth street on the north, and on the south a basin constructed by
the D. L. & W. R. R., 100 feet wide, and 2,300 feet long. The average
level of the marsh land is three feet above mean low water and a foot
and a half below mean high water. In the part built upon the streets are
but two feet above mean high water.

During long easterly and northerly storms, especially at times of high
spring tides, the level of the water in the Hudson is often such as to
cover the meadows even at low tide; and on several occasions the water
at high tide has been 4½ feet above the level of the meadows, and a foot
or more above the established grade of the streets.

The problem is to drain these marsh lands so as to make them properly
habitable and to protect them from invasion by high tides and storm
waters.

The first drainage map of the district was made about fifteen years ago;
since then over $100,000 have been expended on tidal sewers and other
devices, and several acts have been passed by the New Jersey Legislature
in furtherance of the work. An extended review of the plans proposed
and the experiments made thus far is given in a report presented to the
Board of Health and Vital Statistics, last May, by Engineers Spielmann
and Brush. Ten years ago Mr. Arthur Spielmann, on being directed by the
City Council to prepare plans and estimates for a contemplated sewer in
Ferry street to the western boundary of the city, reported adversely
to the project, believing that such a sewer would fail to answer the
purpose of its construction.

There were but two ways, he thought, of securing the end desired: First,
by raising the grade sufficient to give a good drainage; second, by
making reservoirs and forcing the drainage matter out into the river by
steam pumps. The first method he found impracticable on account of the
cost of filling in so large an area and of raising the large number of
houses already on the low ground. The second plan was recommended as
being much cheaper and entirely practicable. Substantially the same
position is taken in the report of last May, wherein it is alleged that
the superior economy of a pumping system has been sufficiently attested
by several eminent hydraulic engineers who have since investigated the
problems involved. On a small scale the efficacy of the pumping system
has been practically tested, first, in Meadow street, between Ferry and
First streets, and more recently in the southern part of the city, where
a number of property owners have kept twenty-five acres free from water
(except during storms) by means of a private pump.

The comparative economy of the pumping system is shown by estimates
in detail of the cost of constructing and operating such a system in
contrast with, the cost of raising the grade and introducing tidal
sewers. Under both systems the cost of the ordinary sewers will be
about the same. A proper system of tidal sewers, it is claimed, will
necessitate the raising of the grade of the streets on the low lands
to a height at least ten feet above mean high water. The extra cost of
raising the streets is estimated at $3,000,000. The cost of the pumping
system, with machinery and power sufficient to remove all storm water
and sewage, is put at $150,000, while the running expenses, including
interest on the first outlay, are put at $30,000 a year. The interest on
the preliminary expenditure of the first plan considered is $180,000 a
year, or six times as much as the pumping system would involve.

According to the estimates made by Engineer Kirkwood, in his report
of 1874, a total pumping capacity of 134,500,000 gallons a day will
ultimately have to be provided to meet the requirements during the
heaviest storms, besides some six or seven million gallons a day of
sewage proper, exclusive of storm waters. Not more than half that amount
of pumping will be required at first, the increase to be made gradually
as the marsh land is built upon.

       *       *       *       *       *




ARTISTS' HOMES--No. 14--"BENT'S BROOK."


Our plate illustrates the residence of Mr. J. E. Boehm, A.R.A., the
sculptor. Bent's Brook is situated at Holmwood, not far south of
Dorking, on the Mid-Sussex line, and commands some fine views of
well-timbered country. The site itself is comparatively low, and the
soil being clay it was advisable to keep the building well out of the
ground, and in this way a rather unusually high elevation for such
a house was obtained. The plan is very compactly arranged, with an
ingenious approach to the well-centered hall and staircase, over
which, by a mezzanine contrivance, a good store place is secured. The
drawing-room has a belvedere bay, reached from the garden by an external
stair, under which is a covered garden seat. A balcony overlooking the
garden leads also from the drawing-room, and a billiard room is arranged
on the basement level with a separate entrance from the porch. A
tradesmen's entrance is provided elsewhere. The kitchen and offices are
on the lower floor level, and a kitchen yard is conveniently placed at
the rear. Red brick, with cut-brick dressings, is the material used
throughout for the walls, the upper parts of which are hung with
ornamental tiles. The gables are enriched with wide, massive barge
boards, and the roof is surmounted with a white wooden cupola over the
principal staircase. The terracotta panels along the entrance front,
over the principal floor windows, were designed by Mr. Boehm himself.
The work was executed by Mr. H. Batchelor, builder, of Betchworth, and
the architect of the house was Mr. R. W. Edis, F.S.A., who superintended
its erection.--_Building News_.

[Illustration: ARTISTS' HOMES No. 14 "BENT'S BROOK."]

       *       *       *       *       *




ON SOME RECENT IMPROVEMENTS IN LEAD PROCESSES.

[Footnote: Lately read before the Institute of Mechanical Engineers.]

By NORMAN C. COOKSON, of Newcastle.


The author began by stating that probably in few trades have a smaller
number of changes been made during recent years, in the processes
employed, than in that of lead smelting and manufacturing. He then
briefly noted what these changes are, and went on to describe the "steam
desilverizing process," as used in the works of the writer's firm, and
in other works licensed by them, which process is the invention of
Messrs. Luce Fils et Rozan, of Marseilles. It is one which should
commend itself especially to engineers, as in it mechanical means
are employed, instead of the large amount of hand-labor used in the
Pattinson process. It consists in using two pots only, of which the
lower is placed at such a height that the bottom of it is about 12
in. to 15 in. above the floor level, while the upper is placed at a
sufficiently high level to enable the lead to be run out of it into
the lower pot. The capacity of the lower pot, in those most recently
erected, is thirty-six tons--double that of the upper one. Round each
pot is placed a platform, on which the workmen--of which there are two
only to each apparatus--stand when skimming, slicing, and charging the
pots. The upper pot is open at the top, but the lower one has a cover,
with hinged doors; and from the top of the cover a funnel is carried
to a set of condensers. At a convenient distance from the two pots is
placed a steam or hydraulic crane, so arranged that it can plumb each
pot, and also the large moulds which are placed at either side of the
lower pot. The mode of working is as follows:

The silver lead is charged into the upper pot by means of the crane.
When melted, the dross is removed, and the lead run into the lower, or
working pot, among the crystals remaining from a previous operation.

When the whole charge is thoroughly melted, it is again drossed; and in
order to keep the lead in a thoroughly uniform condition, and prevent it
setting solid on the top and the outside, a jet of steam is introduced.

To enable this steam to rise regularly in the working pot, a disk-plate
is placed above the nozzle, which acts as a baffle-plate; and uniform
distribution of the steam is the result. To quicken the formation of
crystals, and thus hasten the operation, small jets of water are allowed
to play on the surface of the lead.

This, it might be thought, would make the lead set hard on the surface;
but the violent action of the steam acts in the most effectual manner
in causing the regular formation of crystals. Owing to the ebullition
caused by this action of the steam, small quantities of lead are forced
up, and set on the upper edges and cover of the pot. From time to time
the valve controlling the thin stream of water playing on the top of the
charge is closed, and the workman, opening the doors of the cover in
rotation, breaks off this solidified lead, which falls among the rest of
the charge, and instantly becomes uniformly mixed with it.

Very little practice enables an ordinary workman to judge when
two-thirds of the contents of the big pot are in crystals, and one-third
liquid; and when he sees this to be the case, instead of ladling out the
crystals ladleful by ladleful, as in the old Pattinson process, he taps
out the liquid lead by means of two pipes, controlled by valves, the
crystals being retained in the pot by means of perforated plates.

The liquid lead is run into large cone-shaped moulds on either side of
the pot; and a wrought iron ring being cast into the blocks thus formed,
they are readily lifted, when set, by the crane. To give some idea of
the rapidity of the process, it may be mentioned that from the time the
lead is melted and fit to work in the big pot, to the time that it is
crystallized and ready for tapping, is, in the case of a 36 ton pot,
from thirty-five to forty-five minutes; and the time required for
tapping the liquid lead into the large moulds is about eight minutes.

Before the lead begins to crystallize, the upper pot is charged with
lead of half the richness of that in the lower pot. Thus, when the
liquid lead has been tapped out of the lower pot, it is replaced by a
similar amount of lead of the same richness as the remaining crystals,
by simply tapping the upper or melting pot, and allowing the contents to
run among the crystals.

The same operation is repeated from time to time, until the crystals are
so poor in silver that they are fit to be melted, and run into pigs for
market.

The large blocks of partially worked lead are placed by the crane in
a semicircle round it, and pass successively through the subsequent
operations. The advantages of the steam process, as compared to the old
six-ton Pattinson pots formerly used by the writer's firm, are: (1) a
saving of two-thirds amount of fuel used; (2) the saving of cost of
calcination of the lead to the extent of at least four-fifths of
all that is used; (3) above all, a saving in labor to the extent of
two-thirds. The process has its disadvantages, and these are a larger
original outlay for plant, and a constant expense in renewals and
repairs. This is principally caused by the breakage of pots; but with
increased experience this item has been very much reduced during the
last two or three years.

The "zinc process" of desilverizing, which is largely used by Messrs.
Locke, Blackett & Co., and was patented in the form adopted by them
about fourteen years since. The action of this process is dependent on
the affinity of zinc for silver. The following is a brief description of
it:

A charge of silver lead, usually about fifteen tons, is heated to a
point considerably above that which is used in either the Pattinson or
the steam process. The quantity of zinc added is regulated by the amount
of silver contained in the lead; but for lead containing 50 oz. to the
ton, the quantity of zinc used is in most cases about 1½ per cent, of
the charge of lead. The lead being melted as described, a portion of
this zinc, usually about half of the total quantity required for the
charge, is added to the melted lead, and thoroughly mixed with it by
continued stirring. The lead is now allowed to cool, when the zinc is
seen gradually to rise to the top, having incorporated with it a large
proportion of the silver. The setting point of zinc being above that
of lead, a zinc crust is gradually formed, and this is broken up and
carefully lifted off into a small pot conveniently placed, care being
taken to let as much lead drain off as possible. The fire is again
applied strongly to the pot, and when the lead is sufficiently heated, a
further quantity of zinc, about one-third of the whole quantity used, is
added, when the same process of cooling and removing the zinc crust is
repeated. This operation is gone through a third time with the remaining
portion--¼ per cent.--of zinc; and if each of these operations has
been carefully carried out, the lead will be found to be completely
desilverized, and will only show a very small trace of zinc. In some
works this trace of zinc is allowed to remain in the market lead, but
at Messrs. Locke, Blackett & Co.'s works it is invariably removed by
subjecting the lead to a high heat in a calcining furnace. The zinc
crusts, rich in silver, are freed as far as possible from the lead by
allowing this to sweat out in the small pot, after which the crusts are
placed in a covered crucible, where the zinc is distilled off, and a
portion of it recovered. The lead remaining, which is extremely rich in
silver, is then taken to the refinery, and treated in the usual manner.
The writer is given to understand that the quantity of zinc recovered is
as high as from 50 to 60 per cent. of the total quantity used.

Although it was said that the rolling or milling of lead remains
unchanged in its main features since the first mill was established, yet
the writer's firm have introduced many important improvements. When lead
is required for sheet making, instead of running out the market lead
into the usual pigs of about one hundredweight each, it is run into
large blocks of 3½ tons. These 3½ ton blocks are taken on a bogie to the
mill-house, where the mill melting pot is charged with them by means
of a double-powered hydraulic crane, lifting, however, with the single
power only.

Three such blocks fill the pot, and when melted are tapped on to a large
casting plate, 8 ft. 4 in. by 7 ft. 6 in., and about 7 in. thick. This
block, weighing 10½ tons, is lifted on to the mill table by the same
crane as fills the pot, but using the double power; and is moved along
to the rolls in the usual manner by means of a rope working on a surging
head. The mill itself, as regards the roll, is much the same as those
of other firms; but instead of an engine with a heavy fly-wheel, always
working in one direction, and connected to the rolls by double clutch
and gearing, the work is done by a pair of horizontal reversing engines,
in connection with which there is a very simple, and at the same time
extremely effectual, system of hydraulic reversing. On the usual method
there is no necessity for full or delicate control of lead mill engines;
but with this system it is essential, and the hydraulic reversing gear
contributes largely to such control. This may be explained as follows:

In all other mills with which the writer is acquainted, when the lead
sheet, or the original block, has passed through the rolls, and before
it can be sent back in the opposite direction, a man on either side of
the mill must work it into the grip of the rolls with crowbars.

In the writer's system this labor is avoided, and the sheet or block is
fed in automatically by means of subsidiary rolls, which are driven by
power. When it is required to cut the block or sheet by the guillotine,
or cross-cutting knife, instead of the block being moved to the desired
point by hand-labor, the subsidiary driven rolls work it up to the
knife; and such perfect control does the engine with its hydraulic
reversing gear possess, that should the sheet overshoot the knife
1/8 in., or even less, the engine would bring it back to this extent
exactly.

Another point, which the writer looks upon as one of the greatest
improvements in this mill, is its being furnished with circular knives,
which can be set to any desired width, and put in or out of gear at
will; and which are used for dressing up the finished sheet in the
longitudinal direction. This is a simple mechanical arrangement, but
one which is found to be of immense benefit, and which, in the writer's
opinion, is far superior to the usual practice of marking off the sheet
with a chalk line, and then dressing off with hand knives. The last
length of the mill table forms a weighbridge, and a hydraulic crane
lifts the sheet from it either on to the warehouse floor or the tramway
communicating with the shipping quay.

       *       *       *       *       *




APPARATUS USED IN BERLIN FOR THE PREPARATION OF GELATINE PLATES.

I.--MIXING APPARATUS FOR GELATINE EMULSION.


The mixing vessel--a porcelain kettle capable of containing twenty
liters, made at the Royal Porcelain Factory at Berlin, whose products
are unequaled for chemical purposes--is also the boiling vessel, and,
therefore, fits tightly, by means of the tin ring with the wooden
handles, on to a large water bath. The light-tight metal lid, which
can be permanently affixed to the kettle, then supports a stirring
arrangement of fine silver, which dips into the emulsion and has blades
formed like a ship's screw.

The arrangements for injecting the silver vary. The simplest consists of
a large glass vessel containing the silver solution, which is closed
by a glass stopper, and terminates below in a funnel running to a fine
point. This funnel-shaped bottle fits into an opening specially made for
it in the lid of the kettle, and while revolving sends a fine stream
into the gelatine. When it is wished to interrupt it, it is only
necessary to raise the glass stopper in order to see the stream dry up
after a short time.

Another arrangement consists of a contrivance constructed on the
principle of the common India-rubber inhaling apparatus, and sends
the silver solution into the gelatine in the form of the minutest
air-bubbles. After the emulsion is boiled in such a kettle it is allowed
to stand until cool, when the ammonia is added. With such a great
quantity of emulsion and so large a water bath sufficient heat is
retained as to allow the action of the ammonia to take place. As soon
as the time set apart for that reaction has elapsed the water bath is
emptied and filled with pieces of ice and iced water, and the kettle
replaced in it.

If the stirring apparatus be now set in motion, even this large quantity
of emulsion will stiffen in at least an hour and a half. It may be
further remarked that, the outside of the kettle being black, the lid
being light-tight, and all the apertures in it being firmly closed,
nearly the whole process can be conducted by daylight, from the mixing
to the stiffening, so that it is very convenient to be able to keep the
emulsion in the same vessel during all these operations.


II.--DIGESTIVE APPARATUS.

It is very desirable that those who do not prepare their emulsion by
boiling, but by prolonged digestion, should possess a regulator which
will keep the temperature at a given point. Such an apparatus would also
be very useful for warming the emulsion for the preparation of plates,
as then one would have no further occasion to pay attention to the
thermometer and gas stove. In the accompanying diagram a simple
contrivance is shown. The gas which feeds the stove passes through
a narrow glass tube, a b, into the wider tube, c d e, which is made
air-tight at e. This latter tube has an exit tube at f, by which the gas
is supplied to the gas stove. At e it is hermetically closed, and at its
deepest part it contains mercury, upon which a little sulphuric ether
floats in the hermetically-closed limb, e.g. Lastly, there is a minute
opening in the narrowest tube at i. The whole apparatus, or, at least,
the under part of it, is dipped into the water bath warmed by the gas
boiler. It acts thus: As the temperature rises the ethereal vapor in the
shorter limb expands and drives the mercury up the longer tube until
it closes the opening of the narrow tube, a b, and thereby impedes the
power of the stream of gas. Still, the Bunsen burner does not go out,
being always fed by the small opening, i, with sufficient gas to support
a small flame until the water bath has so far cooled as to leave the
opening at b free, when the burner again burns with a strong flame. By
removing the cork, c, from the tube the temperature of the water bath is
raised, while by pushing it in it is lowered. The apparatus never goes
wrong, and is very cheap. It was first made by Herr C. Braun, of Berlin.

[Illustration: FIG. 1.]


III.--TRITURATING APPARATUS.

The apparatus hereafter described is in general use, and was invented
by Herr Paul Grundner, of Berlin. It is particularly adapted for finely
dividing large quantities of emulsion. It consists essentially of a
wooden lid, a b, fitting upon a large stone pot, to the under side of
which two strong trapezoid pieces of wood, e d and e f, are fixed, in
the under part of which semicircular incisions are cut and held together
by two leather straps, supporting a strong, easily-removable iron
transverse bar, g h. Through the center of the lid, and turned by the
crank, m, passes the axle i, which ends under the lid in the long ring,
n.

The stiffened emulsion is then placed in the bag, o p q r, made of
fine but strong canvas, with meshes about 0.5 mm. (such as is used for
working upon with Berlin wool). The iron rod, g h, is then slipped
through the four loops at the bottom of the bag, the open end is slung
upon the ring, n, and bound tightly to it by the ribbons, r1. The loops
upon the iron bar are then pushed as close together in the middle as
possible, and the stone vessel is filled with water until o p q r is
completely covered. The crank is then turned, by which the bag is wrung,
and the emulsion squeezed through the meshes immediately into the water.
When this process is continued until the purse between n and g h feels
like a metal rod, the best part of the emulsion has been squeezed
through, and if one now take out the bag and dissolve its contents, it
will be found that the loss of emulsion is almost _nil_.

[Illustration: FIG. 2.]

It may be remarked that the whole apparatus, with the exception of the
crank, must be coated with asphalt varnish; also that the corners, r and
q, must be separated off from the purse, as shown by the dotted line, s
s s s, otherwise the emulsion would lodge there without being squeezed
through. Instead of g h a strong glass rod may be used for small
apparatus; but for large apparatus it is indispensable, as the power
that requires to be exerted would be far too great for glass.


IV.--WASHING APPARATUS.

The fundamental idea of the apparatus shown in Fig. 3 first occurred
to Herr Jos. Junk, of Berlin. In the present form all the subsequent
improvements made by Herren Carl Such, Paul Grundner, and others are
incorporated. It may be described as follows:

A tin vessel, the bottom of which sinks at e into the shape of a funnel,
rests upon strong iron feet, f f, and is covered with a lid, having a
double edge closing it light-tight. Through the center of the lid passes
the tube, g h, by which the water enters. In the interior of the vessel
upon iron hooks stands a wooden vessel saturated with paraffine, open at
the ends, and over one end of which the finest hair cloth is stretched
at o p. The water which enters the vessel runs off through the siphon.
The proceedings are as follows: Turn the granulated gelatine and the
water in which it is contained into the horsehair sieve, m n o p. Place
the lid upon the apparatus and turn on the water. The whole apparatus
fills with water until the siphon begins to act. If the diameter of
the siphon be properly measured--one inch should be sufficient for the
largest apparatus--and the cock by which the water is turned on properly
adjusted, more water will run out by the siphon than runs in through the
supply pipe, and the apparatus becomes completely empty.

The siphon has then performed its function, the apparatus fills again,
and the play begins anew. The tube, g h, which reaches right down nearly
to the bottom of the sieve, takes the water so deep into the vessel
that, as long as the water in the apparatus stands high enough above o
p, the gelatine nodules are in continuous motion. In order to prevent
the finest particles of the emulsion from stopping up the pores of the
sieve too much, and thereby incurring the danger of the water in the
sieve overflowing its upper edge, thus occasioning loss of emulsion,
the tube, g h, is now sometimes omitted and replaced by a supply pipe,
represented in the diagram by the dotted lines, x y. In this way
every possibility of loss is excluded, and yet a very careful washing
provided. Then when, after being emptied by the siphon, the apparatus
fills again, every particle of the emulsion which might have formerly
been pressed down into the interstices of the sieve would now be driven
up again by the upward pressure of the water entering from below, and
thus the sieve would always be kept clear and open.

[Illustration: FIG. 3.]

The great advantages of this apparatus are as follows: 1. From the
moment the lid is closed one can work by daylight. 2. The method of
washing in moving water is combined with that of complete change of
water. 3. The emulsion never comes in contact with metal. 4. Whoever
wishes to prepare dry gelatine only requires, when the washing is over
and the vessel perfectly emptied, to leave the emulsion to drip for a
time, and then to lift out the sieve and its contents and place it in
a suitable vessel with absolute alcohol. The latter should be changed
once, and when sufficient water has been extracted the sieve should be
withdrawn from the vessel and the emulsion allowed to dry spontaneously.
In this way all trouble occasioned by changing from vessel to vessel is
avoided, and there is no loss of material.

This apparatus is principally valuable in dealing with large quantities,
since it saves a great deal of labor, and affords perfect certainty of
the emulsion being well washed. It may not be unnecessary to maintain
that the difficulties of perfect washing--particularly if one do not
wash with running water--increase at least in quadruple proportion to
the quantity of emulsion manipulated.--_Franz Stoke, Ph.D., in Br. Jour,
of Photography_.

       *       *       *       *       *




HOW TO MAKE EMULSION IN HOT WEATHER.

By A. L. HENDERSON.


Numerous complaints have reached me within the last few weeks of the
difficulty experienced in preparing emulsion and coating plates; one is
very likely to blame everything but the right, but doubtless the weather
is the culprit.

I have always held that to boil gelatine is to spoil it, and, even when
emulsification is made with a few grains to the ounce and cooled down
before adding the bulk, the damage is done to the smaller quantity,
so that when mixed it contaminates the whole mass; moreover, it is
impossible to set and wash the gelatine without the aid of ice.

I have lately made several batches (with the thermometer at 92° in the
shade, and the washing water at 78°) as follows:

  Hard gelatine...............,......    ½  ounce.
  Water..............................  2    ounces.
  Alcohol............................  2      "
  Bromide ammonia....................150    grains.
  Liquor ammonia, 880................ 60    drops.

When all is thoroughly dissolved and of about 120° temperature, add,
stirring all the time,

  Nitrate silver..................... 60    grains,
  Water..............................    ¾  ounce.
  Alcohol............................    ¾    "

Then again add,

  Nitrate silver.....................140    grains.
  Water..............................  1    ounce.
  Alcohol............................  1      "

Both solutions being warmed to about 120°.

My object is adding the silver in two quantities will be obvious to
many--viz., when the first portion of silver is mixed, nitrate of
ammonia is liberated (which is a powerful restrainer), and the bulk of
the solution being increased, the remainder of the silver may be added
in a much more concentrated state.

The alcohol, both in the gelatine and silver solutions, plays a most
important part: (1) It prevents decomposition of the gelatine. (2) It
allows the gelatine to be precipitated with a much smaller quantity of
alcohol (say about 10 ounces).

After letting the emulsion stand for a few minutes to ripen, I pour in
slowly about eight ounces of alcohol, stirring all the time, and keeping
the emulsion warm; the emulsion will adhere to the stirring-rod and the
bottom of the vessel in a soft mass, and all that is now required is to
pour away the alcohol, allow the emulsion to cool, tear it into small
pieces, wash in several changes of cold water, make up the quantity to
ten ounces, and strain; it is then ready for coating.

By this formula I have no difficulties whatever; my plates set in about
five minutes, and their quality is such that, "unless a better method is
devised," I intend to adopt it in all weathers.

One word more as to the alcohol. It will prevent the decomposition of
gelatine when boiling goes on, or when in the presence of foreign salts;
no flocculent deposit is noticed in the alcohol after the emulsion has
been precipitated.--_Photographic News_.

       *       *       *       *       *




THE DISTILLATION AND RECTIFICATION OF ALCOHOLS BY THE RATIONAL USE OF
LOW TEMPERATURES.

By RAOUL PICTET.


The industrial problem of the rectification of alcohols is based
entirely upon the properties of volatile liquids, upon the laws of the
maximum tensions of the vapors of these liquids, and upon the influence
of temperature upon those different elements which find themselves in
presence of each other in an alembic.

If we desire to follow, in their least details, all the phenomena which
succeed one another in a rectifying column, and which are connected with
one another by a continuous chain of reciprocal influences, the problem
becomes exceedingly complex.

[Illustration: PICTET'S APPARATUS FOR THE RECTIFICATION OF ALCOHOL BY
COLD.]

In order that the new applications of the mechanical theory of heat may
be readily understood, we shall divide this problem into a series of
propositions, which we shall examine separately, and which collectively
constitutes in its general features the methodical rectification of
liquids.

I. Knowing the maximum tensions of pure water and pure alcohol, can we
calculate directly the tensions of the vapors of any mixture whatever of
alcohol and water?

Yes, we can calculate this tension by a general formula, provided we
take into account the affinity of water for alcohol, which increases the
value of the total latent heat of evaporation of the liquid. The results
of the calculation are fully confirmed by experience. We thus establish
the following laws:

a. For any temperature whatever, the maximum tension of the vapors of a
mixture of water and alcohol is always comprised between that of pure
water and that of pure alcohol.

b. The tension of the vapors of a mixture of water and alcohol
approaches the tension of alcohol so much the nearer in proportion as
the proof is higher; and, reciprocally, if water is in excess, the
tension of the vapors approaches the tension of the vapors of water.

c. The curves of the maximum tensions of vapors formed by all mixtures
of alcohol and water are represented by the same general formula, one
factor only of which is a function of the richness of the alcoholic
solution.

It results, then, from these laws that we may determine with the
greatest exactness the richness of a solution containing alcohol and
water, if we know the tension of the vapors that it gives off at a
certain temperature. Such indications are confirmed by the centigrade
alcoholmeter.

We see likewise that, for these solutions of alcohol and water, the
laws of Dalton are completely at fault, since the total pressure of the
vapors is never equal to the sum of the tensions of the two liquids,
water and alcohol.

II. Being given a solution of water and alcohol, mixed in equal volumes,
what will be the quality of the vapors emitted from it?

In other terms, do the vapors which escape from a definite mixture of
water and alcohol also contain volumes of vapor of water and alcohol in
the same proportion as the liquids?

We have discovered the following laws:

d. The quality of the vapors emitted by a mixture of water and alcohol
varies according to the alcoholic richness of the solution, but is not
in simple proportion thereto.

e. The quality of the vapors emitted by a definite mixture of water and
alcohol varies according to the temperature.

f. In a same solution of water and alcohol, it is at low temperatures
that the vapors emitted by the mixture contain the largest proportion of
alcohol.

g. The more the temperature rises the more the tensions of the two
liquids tend to become equalized.

We have been able to verify these different laws experimentally, and
to find an interesting confirmation of our general formula of maximum
tensions, in the following way:

Let us take a test tube containing a 50 per cent. solution of alcohol
and water, plunge it into water of 20°C., and put its interior in
hermetic communication with the receiver of a mercurial air-pump.

We vaporize at 20° a certain quantity of the liquid, and the vapors
fill the known capacity of the pump. The pressure of the gases in the
interior is ascertained by a pressure gauge, and this pressure should be
constant if care is taken to act upon a sufficient mass of liquid and
with moderate speed. When the receiver of the air-pump is full of
vapors, communication between it and the test-tube is shut off, and
communication is effected with a second test-tube, like the first,
plunged into the same water at 20°. Care must be taken beforehand to
create a perfect vacuum in this test-tube.

On causing the mercury to rise into the space that it previously
occupied, the vapors are made to condense in the second test-tube at the
same temperature as that at which they were formed.

We immediately ascertain that the pressure-gauge shows an elevation
of pressure; moreover, the proof of the condensed alcohol has very
perceptibly risen.

If, instead of causing these vapors to condense in the second test-tube,
we leave the first communication open, the vapors recondense in the
first test-tube without any elevation of pressure; and we do not see the
least trace of liquid forming in the second test tube.

This difference of pressure in the two foregoing experiments must be
attributed, then, to the specific action of the water on the vapors of
alcohol. Now we can calculate the difference of the work of the pump,
and put at 1 kilogramme of condensed liquid the difference of mechanical
work represented in kilogrammeters. What is remarkable is that this
difference is absolutely the equivalent of the heat disengaged when the
condensed liquid and the old liquid are remixed; there is a complete
identity. Thus the affinity of the water for the alcohol modifies the
tension of the vapors which form or condense upon the free surface of
the mixture. The two phenomena are closely connected by the law of
equivalence.

It results from all the laws that we have cited that by properly
regulating the tensions of the vapors of a mixture of alcohol and water,
and the temperature of the liquid, we shall be able to obtain a liquid
of a desired richness by the condensation of these vapors.

III. It was likewise indispensable to make sure of one important fact:
When the temperature of a liquid like alcohol is considerably lowered,
can the distillation of a given weight of this substance be effected
with sufficient rapidity for industrial requirements? Repeated
experiments with a host of volatile liquids have demonstrated the
following laws:

If we introduce a volatile liquid into two spherical receivers connected
by a wide tube, and if these be kept at different temperatures after
driving out all the air from the apparatus, the liquid distills from the
warmer into the cooler receiver, and we ascertain that:

h. The weight of the liquid which distills in the unit of time increases
with the deviation of temperature between the two receivers.

i. The weight of the liquid which distills in the unit of time is
constant for a same deviation of temperature between the receivers,
whatever be, moreover, the absolute temperature of the receivers.

k. The weight of the liquid distilled in the unit of time is
proportional to the active surfaces of the receivers; that is to say,
to the surfaces which are the seat of passage of heat through their
thickness.

l. The least trace of a foreign gas in the vapors left in the apparatus
throws the preceding laws into confusion, and checks distillation to a
considerable degree, especially at low temperatures.

Thus, water distilling between 100° and 60° will pass over as quickly
as that which is distilling between 40° and 0°. Absolute temperature is
without influence, provided every trace of air or foreign gas be got rid
of.

The distillatory apparatus should be provided with an excellent
air-pump, capable of preventing all those entrances of air which are
inevitable in practice.

The following is the industrial application that we have endeavored to
make of these theoretical views: The rectification of alcohols is one
of the most complex of operations; it looks toward several results
simultaneously. Alcohol derived from the fermentation of grain, sugar,
and of all starchy matters in general, contains an innumerable host of
different products, which may be grouped under four principal heads:

1. Empyreumatic essential oils, characteristic of the source of the
alcohol, and having a powerful odor which infects the total mass of
the crude spirits. 2. A considerable quantity of water. 3. A certain
quantity of pure alcohol. 4. A variable proportion of volatile
substances, composed in great part of ethers, different alcohols, and
bodies as yet not well defined. These latter affect the quality of
the alcohol by an odor which is entirely different from that of the
essential oils.

The object of rectification is to bring out No. 3 all alone; that is
to say, to extract the alcohol in a pure state by ridding it of oils,
water, ether, and foreign alcohols.

The alcohol industry never realizes this operation in an absolutely
complete manner. All the rectifying apparatus in operation at the
present day are based on the use of high temperatures varying between
78.5° and 100°. The successive condensation and vaporization of the
vapors issuing from the spirits effect in the rectifying columns a
partial separation of these liquids, and there are received successively
as products of rectification:

1. Bad tasting alcohols, containing the majority of the ethers and
impure alcohols.

2. Fine alcohol.

3. Alcohols contaminated by notable proportions of empyreumatic oils.

Industry knows only one means of obtaining an excellent product, and
that is to diminish the quantity of fine alcohol which comes from a same
lot of spirits, and to make a large number of successive distillations.
Hence the large expenses attending rectification, which produce fine
alcohols necessarily at an elevated price. We may remark, in passing,
that the toxic action of commercial alcohols is in great part caused by
the presence of essential oils, amylic alcohol, and ethers, absolutely
pure alcohol, as compared with these, being relatively innocent.

Why is it that our present apparatus cannot produce good results in
rectifying alcohol? Because they are limited by the temperature at which
they must operate. Between 78° and 100° the tension of the vapors of all
the liquids mixed in the spirits is considerable for each of them; they
all pass over, then, in certain proportions during the operation of
rectification.

We have been led, by examining the theoretical question, to ascertain
that the proportion of alcohol which evaporates from a mixture is
maximum at low temperatures; consequently, we should seek to establish
some arrangement which can realize the following conditions: (1) Render
variable, at will, the temperature of the boiling liquid; and (2),
render variable the pressure of the vapors which act on the liquid.

Thus, to effect the rectification of alcohol it suffices to cause its
ebullition at very low temperatures, and to keep up the ebullition
without changing such temperatures when once obtained.

It is exactly these two conditions that we have fulfilled in the
apparatus that we have just installed in our factory in Rue Immeubles
Industriels, at Paris.

By their arrangement, which is shown in the opposite figure, they form
a mechanical system permitting of the rectification of alcohols at
temperatures as low as -40° or even -50°. They verify experimentally, by
their operation, the theoretical deductions which precede. The boilers,
A, which, in an industrial application, may be more numerous, receive
their supply of spirits from the country distilleries in the vicinity of
the factory. There may even be introduced directly into them _vinasses_,
or washes, that is to say, liquids, such as are obtained by alcoholic
fermentation.

Above the boiler rises a rectifying column composed of superposed plates
inclined one over the other, and surmounted by a tubular condenser,
which serves to effect the retrogression of the first condensation by
means of a current of water supplied by the reservoir placed above.

On leaving this condenser, the vapors which have escaped condensation
pass into the refrigerator, C, where they are totally condensed by a
current of water which goes to the reservoir above.

The first products obtained contain ethers and impure alcohols, which
are collected in the reservoir, E.

When the first products have been thus introduced into the reservoir,
and it is ascertained by tasting that good alcohol is passing over,
the liquid produced is directed into the second boiler, F. The sliding
valve, operated by a screw having a very fine pitch, establishes a
communication between the refrigerator, C, and the second boiler, F. The
office of this valve we shall learn further on. This first rectification
is performed in a vacuum, for a system of metallic pipes connects the
entire apparatus with an air-pump, O. The temperature at which the
liquids shall enter into ebullition in the boilers, A A, may, then, be
regulated in advance.

The operations will be carried on with a more or less complete vacuum,
according to the nature of the products to be rectified. The distiller
will have to be guided in this by practice alone.

The good tasted products are received in boiler No. 2, F, and there the
liquids are submitted to the action of an almost absolute vacuum. As we
have before said, their temperature falls immediately and spontaneously.
The vapors which issue from this liquid contain almost solely pure
alcohol. The other substances, which passed over in the first
distillation, no longer emit vapors at temperatures ranging between -10°
and +5°. Their temperature is shown by a thermometer running into the
boiler, F.

These vapors, purified by ebullition at a low temperature, rise into a
second rectifying column, G, which terminates in the refrigerator, H,
filled with liquid sulphurous anhydride. This refrigerator is like those
which we employ in our sulphurous anhydride frigorific apparatus. Under
the action of a special pump, M, this liquid produces and maintains a
constant temperature of -25° to -30° in the refrigerator. The vapors of
alcohol condense therein at this low temperature, and the cold liquid
alcohol flows into the lower part of the refrigerator.

By the action of a return cock, a portion of this liquid falls upon
the plates of the column, G, and descends, while the vapors are rising
therein. The other portion of the liquid obtained flows into the
reservoir, K, at the beginning of the operation, and into the reservoir,
L, during all the remainder of the rectification. The ice-making machine
keeps up of itself alone the two operations.

In fact, the exhaust of the steam engine which actuates the sulphurous
anhydride pump is directed into a worm which circulates through the
first boiler, A, and the refrigerator, H, of the frigorific machine
keeps up the second rectification, which was brought about below the
surrounding temperature, and which for this reason takes place without
necessitating any combustion of coal. It suffices to cause the current
of water which issues from the condenser of the frigorific machine to
pass into the worm of the boiler.

We have, then, two results, two like operations, both produced by
the working of a single machine. Moreover, these two operations are
performed _in vacuo_, and we know that under these conditions they are
effected at lower temperatures. Owing to this fact, likewise, the weight
of the water that must be evaporated diminishes just so much. Now, one
kilogramme of water requires 636 heat units to cause it to pass from the
liquid to the gaseous state, while one kilogramme of alcohol requires
only 230 heat units to vaporize it. Thus every decrease of temperature
in rectification has for an immediate corollary an important economy of
fuel, which is proved by the diminution of radiation, and by the less
quantity of water to be distilled.

Between the boilers, A, in which is maintained a temperature bordering
on +50° to +60°, and the refrigerator, H, in which is easily obtained
a temperature of -30° to -40°, there is at our disposal a range of
temperature of nearly 100°, an immense difference compared with that
which can be made use of in ordinary apparatus. Thanks to this powerful
factor, which is manageable at will, we can take directly from the
apparatus alcohols marking 98 and 99 degrees by the centigrade
alcoholmeter. Such results are unobtainable by the usual methods.

We have likewise ascertained that at low temperatures the ebullition of
alcohol is as active as at near 100°.

For a same range of temperature between the boiler and the refrigerator,
the weight of alcohol which distills in an hour is constant. By the
operation of the valve, D, it becomes easy to allow all the liquid
condensed in the first refrigerator to pass into the second boiler;
and thus the second rectification, which is effected in a more perfect
vacuum, is supplied with exactness. The object of this valve, then, is
to allow the liquid to pass, and yet to cut off the pressure in such
a way as to have a double fall of temperature throughout the whole
apparatus; from 60° to 20° in the first operation, and from 0° to -40°
in the second. We may add that the regulation of the valve is extremely
easy, because of the screw which actuates it.

To sum up the commercial advantages that our process procures, we may
say that it realizes the following _desiderata_: 1. With the cost of a
single distillation we have, at once, distillation and rectification,
or a single expense for two results. 2. With one operation at a low
temperature we obtain products which are almost impossible to get even
by an indefinite number of rectifications at a high temperature, the
temperature having an intrinsic value in the operation. 3. The alcohols
obtained are wholesome, and can be put on the market without danger. 4.
Their superior quality gives these alcohols an extra value difficult
to calculate, but which is very notable. 5. The whole operation being
performed in closed vessels, there is absolutely no waste. 6. For the
same reason there is scarcely any danger of fire. 7. The management of
the works and the service are performed by the pressure of the gases
entirely; there are only a few cocks to be turned to perform all the
interior maneuvers, empty and fill the vessels, etc. Hence economy in
_personnel_.

       *       *       *       *       *




ELECTROLYTIC DETERMINATIONS AND SEPARATIONS.

[Footnote: NOTE.--Each of these determinations was accompanied by a
series of results in which the practical determinations obtained from
the method described were compared with the theoretical contents of the
solutions of the various elements. These, however, would take up too
much room for insertion in these columns.]

By ALEX. CLASSEN and M.A. VON REIS; translated by M. BENJAMIN, Ph.B.,
F.C.S.


Ever since the electrolytic method for the estimation of copper came
into general use, numerous chemists have endeavored to adapt this
peculiarly simple and elegant method to the determination of other
metals. According to the experiments which have been made up to the
present time, it has been found that the separation of copper is best
effected in a nitric acid solution, while that of nickel and cobalt
takes place most readily in an ammoniacal solution, and for the
precipitation of zinc and cadmium a potassium cyanide solution is the
best. The accuracy of the results depend chiefly upon the following of
certain fixed rules, such as, for instance, that the precipitation of
copper only takes place when there is a definite amount of nitric acid
in the solution; that of cobalt and nickel when a certain quantity of
ammonium hydrate and ammonium sulphate is present. The electrolytic
decomposition of the chlorides has not yet been successfully
accomplished, so that prior to the operation it is necessary to convert
them into sulphates. The experiments which have been made for the
purpose of investigating the application of the electric current in
quantitative analyses are very few, about the only exception being the
separation of copper from the metals which are not precipitated from a
nitric acid solution, or which are deposited as peroxides at the other
electrode. We shall endeavor to show in that which follows, that copper,
zinc, nickel, and cobalt, and even iron, manganese, cadmium, bismuth,
and tin, whether they be present as sulphates, chlorides, or nitrates,
may be precipitated and separated from each other by electrolytic
methods much more rapidly than by any previously known process.


DETERMINATION OF COBALT.

Neutral potassium oxalate is added in excess to the solution of a cobalt
salt, and the clear solution of cobalt potassium oxalate submitted to
electrolysis. The intense red color of this solution is soon changed
into a dark green; the latter diminishing in intensity as the metal is
deposited at the negative electrode. The electric current decomposes the
potassium oxalate into the carbonate, so that a precipitate of cobalt
carbonate is simultaneously formed with the separation of the metallic
cobalt. This precipitate may be dissolved by adding oxalic acid or
dilute sulphuric acid; the further action of the current will change the
solution to an alkaline reaction, upon which the treatment with acid is
repeated until all the cobalt has been separated out in its metallic
condition. The electrolytic separation of cobalt is much more easily
and rapidly effected when the potassium oxalate is substituted by the
corresponding ammonium salt, as the latter forms a soluble double
salt with the cobalt compounds. If the ammonium oxalate added is just
sufficient to form the double salt, a red cobalt oxalate (_which is only
slowly reduced by the current_) will separate out in addition to the
cobalt. In order to obviate this difficulty, the solution to which the
ammonium oxalate had been added in excess is heated, and then three
or four grammes more of solid ammonium oxalate are added. The _hot_
solution, when exposed to the action of the current, deposits the cobalt
as a closely adhering gray film. By the aid of two Bunsen's elements,
0.2 gramme cobalt can be separated in an hour's time. When the reduction
has been completed, and this is best determined by testing a small
sample (removed by a pipette) with ammonium sulphide, the positive
electrode[1] is removed from the solution, and the liquid poured off.
The dish is immediately rinsed several times with water, and the excess
of water removed at first with alcohol, and then with absolute ether.
The cobalt in the dish is dried in the air bath at 100° C., and in the
course of a few minutes a constant weight is obtained.

[Footnote 1: A piece of platinum foil, 4.5 cm. in diameter, is used
for the positive electrode, and a deep platinum dish as the negative
electrode.--_Vide_ "Classen's Quantitative Analysis," 3d Edition, p.
46.]


DETERMINATION OF NICKEL.

This process is precisely identical with the previously described method
for cobalt. The ammonium oxalate is added in excess to the solution,
which is then heated, and four more grammes of the solid salt added. The
separation of the nickel is as rapid as that of the cobalt. The nickel
is precipitated as a gray, compact mass, tightly adhering to the
electrode.


DETERMINATION OF IRON.

For this estimation, solutions of the chloride as well as those of the
sulphate (ammonium, iron, alum) may be used in the manner previously
described. The electrolysis is best effected in the presence of a
sufficient quantity of ammonium oxalate; no separation of any iron
compound takes place. The iron is deposited in the form of a bright,
steel gray, firmly-adhering mass on the platinum dish. The iron may be
exposed to the air for several days without any noticeable oxidation
taking place.


DETERMINATION OF ZINC.

Zinc may be separated from a solution of the double salt fully as easily
and rapidly as the previously mentioned metals were. The reduced zinc
has a dark gray color, and adheres very firmly to the electrode. The
separated metal is dissolved by using dilute acids and heating. It is
only removed with difficulty, and generally leaves a dark coating on the
dish, which is separated by repeated ignitions and treatment with acid.


DETERMINATION OF MANGANESE.

It is already known that manganese may be separated as the peroxide from
its nitric acid solution. We find, however, that the precipitation is
only completely effected when the quantity present is small; the amount
of nitric acid must also be slight, and it is necessary to wash the dish
without interrupting the current. If the manganese is converted into
the soluble double salt, prepared by adding an excess of potassium, and
submitted to the electric current, the whole of the manganese will be
deposited at the positive electrode. When ammonium oxalate is used, the
complete precipitation does not take place. As the separated peroxide
does not adhere firmly to the electrode, it is necessary to filter it
and convert it, by ignition, into the trimangano-tetroxide (Mn_3O_4).


DETERMINATION OF BISMUTH.

This separation presents considerable difficulty, because the metal
is not precipitated as a compact mass on the platinum. The bismuth is
always obtained in the same form, no matter whether it is precipitated
from an acid solution, or from the double ammonium oxalate, or, finally,
from a solution to which potassium tartrate has been added. As large a
surface as possible must be used, and the dish piled to the rim; then,
if the quantity of bismuth is small, the washing with water, alcohol,
and ether may be effected without any loss of the element. If small
quantities of the metal separate from the dish, they must be collected
on a tared filter, and determined separately. In our experiments, an
excess of ammonium oxalate was added to a nitric acid solution of
bismuth. During the electrolytic decomposition, a separation of the
peroxide was observed at the positive electrode, which, however, slowly
disappeared. In order to prevent the reduced metal from oxidation, the
last traces of water are completely removed by repeated washings with
alcohol and anhydrous ether.


DETERMINATION OF LEAD.

The nitric solution of lead acts similarly to that of manganese. When
the amount of peroxide separated is so large that it does not adhere
firmly, and becomes mechanically precipitated on the negative electrode,
it becomes impossible to complete the estimation without loss from the
solution of the peroxide, and the results cannot be accepted.

If the double oxalate is submitted to electrolysis, the whole of the
lead is separated out in its metallic state, but it is so rapidly
oxidized by the air that it is very seldom that it can be dried without
decomposition even when the operation is conducted in a current of
illuminating gas. The electrolytic estimation of this element cannot be
recommended.


DETERMINATION OF COPPER.

The copper may be very easily and rapidly separated from the double
ammonium oxalate salt, provided a sufficient excess of ammonium oxalate
is present. Weak currents cannot be employed for the determination of
this element when it is present in large quantities, for under such
circumstances the metal does not adhere with sufficient firmness to the
electrode. We employed a current which corresponded to an evolution of
330 c.c. of gas per hour, and we were able to precipitate 0.15 gramme
metallic copper in about twenty-five minutes.


DETERMINATION OF CADMIUM.

When the cadmium ammonium oxalate is submitted to the action of the
electric current, the metal is thrown down in the form of a gray
coating, which does not adhere very firmly to the electrode, but,
however, sufficiently so as not to become separated on careful washing.


DETERMINATION OF TIN.

Tin may be easily estimated by electrolysis; it can be separated from
its hydrochloric acid solution, or from its double salt with ammonium
oxalate, as a beautiful silver gray coating on the platinum. When the
ammonium oxalate is substituted by the potassium salt, the operation
becomes more difficult, as a basic salt is formed at the opposite
pole, and is not easily reduced. If the tin is separated from an acid
solution, the current must not be interrupted while the washing takes
place, a precaution which it is not necessary to follow when the
ammonium oxalate is used. When the tin is dissolved from the platinum
dish, it acts like the zinc; that is to say, a black coating is left on
the electrode.


DETERMINATION OF ANTIMONY.

Antimony may be precipitated in its metallic state from a hydrochloric
acid solution, but it does not adhere very firmly to the electrode.
If potassium oxalate is added to a solution of the trichloride, the
antimony may be readily reduced, but the metal adheres still less firmly
to the electrode than it did in the first instance. An adherent coating
may be obtained by adding an alkaline tartrate, but in that case the
separation takes place too slowly. The precipitation of antimony may be
very readily effected from solutions of its sulpho salts.

To a liquid, which may contain free hydrochloric acid, hydrogen sulphide
is added, then neutralized with ammonium hydrate, and saturated with
ammonium sulphide in excess. The reduction may be accelerated by the
addition of some ammonium sulphate. The antimony separates out as a
fine, light gray precipitate on the electrode, and which adheres very
firmly, provided the precipitation has not been carried on too rapidly,
_i. e._, if the current employed for the reduction was not too strong.

When the reduction has been completed, the supernatant liquid is poured
off, and the residue washed in the ordinary manner.


DETERMINATION OF ARSENIC.

Arsenic cannot be completely separated from either its aqueous
hydrochloric acid, or from a solution to which ammonium oxalate has been
added in excess. From its aqueous as well as from its oxalate solution,
a portion of the metal may be separated, but if the current is passed
through its hydrochloric acid solution for a sufficient length of time,
all the arsenic will be volatilized as arsenious hydride (AsH_3).


SEPARATION OF IRON FROM MANGANESE.

If a solution of ferric oxide and manganese ammonium oxalate is
submitted to electrolysis, without the previous addition of ammonium
oxalate, the characteristic color of permanganic acid immediately makes
its appearance, and the peroxide gradually precipitates itself on the
positive, while the iron is deposited on the negative electrode. When
the examination is made in the above manner, it is impossible to
separate the two metals, for the peroxide will bring down with it a
considerable quantity of ferric hydrate. The separation of the two
metals is only possible when the precipitation of the manganese peroxide
is prevented, until the greater portion of the iron has been deposited.
This result may be attained by adding sodium phosphate, or, better
still, by the addition of ammonium oxalate in great excess. In both
cases the characteristic coloration from permanganic acid is developed
by the action of the current at the positive pole; this, however,
disappears in the direction of the negative electrode. After the greater
portion of the ammonium oxalate has been converted into carbonate, the
coloration and necessarily the formation of manganese peroxide begins.

Ammonium oxalate is added to the solution, and heat applied; then three
or four grammes more of ammonium oxalate are dissolved in the liquid,
which is then immediately submitted to electrolysis. When the amount of
manganese is small, the separation of the two elements takes place very
rapidly, and the results are accurate. If the amount of manganese is
more than double that of iron, the separation of the latter will take a
much longer time. Then, in order to effect a complete separation of the
two elements, it is necessary to redissolve the deposited manganese in
oxalic acid (the acid is added, without interrupting the current, until
the liquid becomes red), and the current is allowed to continue its
action.

It was found desirable, in effecting this separation, not to employ
too strong a current (two Bunsen elements will suffice), and only
to increase the strength of the current when it is necessary, in
consequence of a large amount of manganese being present, to redissolve
the peroxide.

When the process is completed, it is not advisable to allow the current
to act any longer, for otherwise some of the peroxide may adhere firmly
to the iron, and the latter (after previously having poured off the
liquid) must be redissolved in oxalic acid, that is to say, the
electrolysis must be repeated. As has been already mentioned in the
determination of manganese as peroxide, its precipitation from ammonium
oxalate is not complete. The solution which contains the greater portion
of manganese, suspended as peroxide, must first, therefore, be boiled to
decompose the ammonium carbonate; the remainder of the ammonium oxalate
is neutralized with nitric acid, and the manganese converted into the
sulphide by ammonium sulphide. The manganese sulphide is then ignited in
a current of hydrogen, and weighed as such.


SEPARATION OF IRON AND ALUMINUM.

The quantitative separation of iron from aluminum, which presented many
difficulties according to the older methods, may be easily performed
by electrolysis. If a solution of iron ammonium oxalate and aluminum
oxalate, to which an excess of ammonium oxalate has been added, be
submitted to the action of the electric current, the iron will be
deposited as a firmly adhering coat on the negative electrode, while
the aluminum oxide remains in solution, just so long as the quantity
of ammonium oxalate is in excess of the quantity of ammonium carbonate
produced. When, finally, a precipitation of aluminum oxide takes place
the liquid is almost free from iron. From time to time, the solution, in
which the aluminum oxide is suspended, is tested for iron by ammonium
sulphide, and the current is interrupted when no further reaction is
observed. The best method of procedure is to add ammonium oxalate in
excess to a neutral, a slightly acid solution, or to one which has been
neutralized by the addition of ammonium hydrate (a hydrochloric acid
solution is not well adapted for this purpose); then as much more solid
ammonium oxalate is added until for every 0.1 gramme there is 2 to
3 grammes of the oxalate present. The hot solution is then directly
submitted to the action of the electric current. After the iron has been
precipitated, it is best to stop the action of the current before all
the aluminum oxide is thrown down, for otherwise a portion of the latter
may adhere firmly to the iron, and be difficult to remove.

In such a case, as was mentioned previously in the separation of iron
from manganese, it is necessary to redissolve the iron (after previously
having poured off the liquid) in oxalic acid, and then the electrolysis
is continued.

In order to effect the complete precipitation of the aluminum oxide from
the solution which was poured from the iron, ammonium hydrate is added,
and the solution boiled for some time, and then the aluminum oxide is
determined in the usual manner. When the quantity of aluminum is less
than that of iron, this method may be relied upon to give exact results.
With the reverse (_i. e._, an excess of iron) the precipitate
of aluminum oxide must be dissolved in oxalic acid (without the
interruption of the current), and the electrolysis continued.--_Berichte
der Deutschen Chemischen Gesellschaft_, 14, 1662.

       *       *       *       *       *




THE CULTIVATION OF PYRETHRUM AND MANUFACTURE OF THE POWDER.


In accordance with an announcement in the March number of the
_Naturalist_, the editor of this department has sent out the seed of two
species of pyrethrum, viz. _P. roseum_ and _P. cinerarioefolium_, to
a large number of correspondents in different parts of North America.
Every mail brings us some inquiries for further particulars and
directions to guide in the cultivation of the plant and preparation of
the powder. We have concluded, therefore, that such information as is
obtainable on these heads will prove of public interest, and we shall
ask Professor Bessey's pardon for trenching somewhat on his domain.

There are very few data at hand concerning the discovery of the
insecticide properties of pyrethrum. The powder has been in use for many
years in Asiatic countries south of the Caucasus mountains. It was sold
at a high price by the inhabitants, who successfully kept its nature a
secret until the beginning of this century, when an Armenian merchant,
Mr. Jumtikoff, learned that the powder was obtained from the dried
and pulverized flower-heads of certain species of pyrethrum growing
abundantly in the mountain region of what is now known as the Russian
province of Transcaucasia. The son of Mr. Jumtikoff began the
manufacture of the article on a large scale in 1828, after which year
the pyrethrum industry steadily grew, until to-day the export of the
dried flower-heads represents an important item in the revenue of those
countries.

Still less seems to be known of the discovery and history of the
Dalmatian species of pyrethrum (_P. cinerarioefolum_), but it is
probable that its history is very similar to that of the Asiatic
species. At the present time the pyrethrum flowers are considered by far
the most valuable product of the soil of Dalmatia.

There is also very little information published regarding either the
mode of growth or the cultivation of pyrethrum plants in their native
home. As to the Caucasian species we have reasons to believe that they
are not cultivated, at least not at the present time, statements to the
contrary notwithstanding.[1]

[Footnote 1: Report Comm. of Patents, 1857, Agriculture, p. 130.]

The well-known Dr. Gustav Radde, director of the Imperial Museum of
Natural History at Tiflis, Transcaucasia, who is the highest living
authority on everything pertaining to the natural history of that
region, wrote us recently as follows: "The only species of its genus
_Pyrethrum roseum_, which gives a good, effective insect powder, is
nowhere cultivated, but grows wild in the basal-alpine zone of our
mountains at an altitude of from 6,000 to 8,000 feet." From this it
appears that this species, at least, is not cultivated in its native
home, and Dr. Radde's statement is corroborated by a communication of
Mr. S. M. Hutton, Vice-Consul General of the U. S. at Moscow, Russia, to
whom we applied for seed of this species. He writes that his agents were
not able to get more than about half a pound of the seed from any one
person. From this statement it may be inferred that the seeds have to be
gathered from the wild and not from the cultivated plants.

As to the Dalmatian plant it is also said to be cultivated in its native
home, but we can get no definite information on this score, owing to the
fact that the inhabitants are very unwilling to give any information
regarding a plant the product of which they wish to monopolize. For
similar reasons we have found great difficulty in obtaining even small
quantities of the seed of _P. cinerarioefolium_ that was not baked or in
other ways tampered with to prevent germination. Indeed, the people
are so jealous of their plant that to send the seed out of the country
becomes a serious matter, in which life is risked. The seed of
_Pyrethrum roseum_ is obtained with less difficulty, at least in small
quantities, and it has even become an article of commerce, several
nurserymen here, as well as in Europe, advertising it in their
catalogues. The species has been successfully grown as a garden plant
for its pale rose or bright pink flower-rays. Mr. Thomas Meehan, of
Germantown, Pa., writes us: "I have had a plant of _Pyrethrum roseum_ in
my herbaceous garden for many years past, and it holds its own without
any care much better than many other things. I should say from this
experience that it was a plant which will very easily accommodate itself
to culture anywhere in the United States." Peter Henderson, of New York,
another well-known and experienced nurseryman, writes: "I have grown the
plant and its varieties for ten years. It is of the easiest cultivation,
either by seeds or divisions. It now ramifies into a great variety of
all shades, from white to deep crimson, double and single, perfectly
hardy here, and I think likely to be nearly everywhere on this
continent." Dr. James C. Neal, of Archer, Fla., has also successfully
grown _P. roseum_ and many varieties thereof, and other correspondents
report similar favorable experience. None of them have found a special
mode of cultivation necessary. In 1856 Mr. C. Willemot made a serious
attempt to introduce and cultivate the plant[1] on a large scale in
France. As his account of the cultivation of pyrethrum is the best
we know of we quote here his experience in full, with but few slight
omissions: "The soil best adapted to its culture should be composed of
pure ground, somewhat silicious and dry. Moisture and the presence of
clay are injurious, the plant being extremely sensitive to an excess of
water, and would in such case immediately perish. A southern exposure is
the most favorable. The best time for putting the seeds in the ground is
from March to April. It can be done even in the month of February if the
weather will permit it. After the soil has been prepared and the seeds
are sown they are covered by a stratum of ground mixed with some
vegetable mould, when the roller is slightly applied to it. Every five
or six days the watering is to be renewed, in order to facilitate the
germination. At the end of about thirty or forty days the young plants
make their appearance, and as soon as they have gained strength enough
they are transplanted at a distance of about six inches from each other.
Three months after this operation they are transplanted again at a
distance of from fourteen to twenty inches, according to their strength.
Each transplantation requires, of course, a new watering, which,
however, should only be moderately applied. The blossoming of the
pyrethrum commences the second year, toward the end of May, and
continues to the end of September." Mr. Willemot also states that the
plant is very little sensitive to cold, and needs no shelter, even
during severe winters.

[Footnote 1: Mr. Willemot calls his plant _Pyrèthre du Caucase (P.
Willemoti._ Duchartre), but it is more than probable that this is only
a synonym of _P. roseum_. We have drawn liberally from Mr. Willemot's
paper on the subject, a translation of which may be found in the Report
of the Commissioner of Patents for the year 1861, Agriculture, pp.
223-331.]

The above quoted directions have reference to the climate of France, and
as the cultivation of the plant in many parts of North America is yet
an experiment, a great deal of independent judgment must be used. The
plants should be treated in the same manner as the ordinary Asters of
the garden or other perennial Compositae.

As to the Dalmatian plant, it is well known that Mr. G. N. Milco, a
native of Dalmatia, has of late years successfully cultivated _Pyrethrum
cinerarioefolium_ near Stockton, Cal., and the powder from the
California grown plants, to which Mr. Milco has given the name of
"Buhach," retains all the insecticide qualities and is far superior to
most of the imported powder, as we know from experience. Mr. Milco
gives the following advice about planting--advice which applies more
particularly to the Pacific coast: "Prepare a small bed of fine, loose,
sandy, loamy soil, slightly mixed with fine manure. Mix the seed with
dry sand and sow carefully on top of the bed. Then with a common rake
disturb the surface of the ground half an inch in depth. Sprinkle the
bed every evening until sprouted; too much water will cause injury.
After it is well sprouted, watering twice a week is sufficient. When
about a month old, weed carefully. They should be transplanted to loamy
soil during the rainy season of winter or spring."

Our own experience with _P. roseum_ as well as _P. cinerarioefolium_
in Washington, D. C., has been so far quite satisfactory. Some that we
planted last year in the fall came up quite well in the spring and will
perhaps bloom the present year. The plants from sound seed which we
planted this spring are also doing finely, and as the soil is a rather
stiff clay and the rains have been many and heavy, we conclude that Mr.
Willemot has overstated the delicacy of the plants.

In regard to manufacturing the powder, the flower heads should be
gathered during fine weather when they are about to open, or at the time
when fertilization takes place, as the essential oil that gives the
insecticide qualities reaches, at this time, its greatest development.
When the blossoming has ceased the stalks may be cut within about four
inches from the ground and utilized, being ground and mixed with the
flowers in the proportion of one-third of their weight. Great care must
be taken not to expose the flowers to moisture, or the rays of the sun,
or still less to artificial heat. They should be dried under cover and
hermetically closed up in sacks or other vessels to prevent untimely
pulverization. The finer the flower-heads are pulverized the more
effectually the powder acts and the more economical in its use. Proper
pulverization in large quantities is best done by those who make a
business of it and have special mill facilities. Lehn & Fink, of New
York, have furnished us with the most satisfactory powder. For his own
use the farmer can pulverize smaller quantities by the simple method of
pounding the flowers in a mortar. It is necessary that the mortar be
closed, and a piece of leather through which the pestle moves, such
as is generally used in pulverizing pharmaceutic substances in a
laboratory, will answer. The quantity to be pulverized should not exceed
one pound at a time, thus avoiding too high a degree of heat, which
would be injurious to the quality of the powder. The pulverization being
deemed sufficient, the substance is sifted through a silk sieve, and
then the remainder, with a new addition of flowers, is put in the mortar
and pulverized again.

The best vessels for keeping the powder are fruit jars with patent
covers or any other perfectly tight glass vessel or tin box.--_American
Naturalist_.

       *       *       *       *       *




THE REMOVAL OF NOXIOUS VAPORS FROM ROASTING FURNACE GASES.


In a paper read before the Aix-la-Chapelle section of the _Verein
deutscher Ingenieure_, Herr Robert Hasenclever presents a summary of
the results obtained with various methods for the absorption of the
sulphurous acid generated during the roasting of zinc-blende and other
sulphurets. Though most of our own metallurgical works are not so
located as to be forced to pay much attention to the removal of noxious
vapors, the efforts made abroad possess some interest for American
metallurgists. Besides containing sulphurous acid, the gases from the
roasting furnaces hold varying quantities of sulphuric acid, and Dr.
Bernoulli describes a process applied on a large scale in Silesian zinc
works, where the gases were passed through towers filled with lime. It
was found that there was no trouble on account of the absorption of
carbonic acid by the lime, and that the latter acted very efficiently
in reducing the quantity of sulphurous acid. Before entering the tower,
they contained 0.258 per cent. by volume of sulphurous acid and 2.45 per
cent. of carbonic acid; while, after their passage through it, they
held 0.017 and 2.478 per cent, respectively. The process, however, is
declared by Herr Hasenclever to be too costly for ordinary working,
although he does not deny its value under special circumstances.

The removal of anhydrous sulphuric acid from the gases from
roasting-furnaces has hitherto, as at the Waldmeister works, near
Stolberg, been effected by means of water trickling down in a tower
filled with coke, the gases entering below and moving upward. Herr
Hasenclever tested the Freytag method, in which the water is replaced
by sulphuric acid, and obtained favorable results, as shown by the
following analyses of the gases before and after treatment. The figures
given are grammes per 1,000 liters:

   BEFORE.              AFTER.
 SO_2.   SO_3.       SO_2.   SO_3.
 8.24    0.63        5.74    0.00
 8.29    0.37        6.74    0.07
 9.36    0.69        6.96    0.00
 9.46    0.63        7.38    0.05
10.03    1.08        7.69    0.09
16.52    2.97       14.39    0.23
17.90    1.97       13.32    0.11
17.80    2.46       16.18    0.69

The average absorption for the first set of four analyses when three
roasting-furnaces were discharging into the tower was 95 per cent. of
the sulphuric acid, and that of the second set of four or five furnaces
was 90 per cent. The amount of sulphuric acid charged per twenty-four
hours was about 5,000 kilogrammes of 50 degrees Baumé, which flowed off
with a density of from 56 to 58 degrees Baumé. The quantity of acid
condensed varied according to the nature of the ores and the number of
furnaces working. It ranged between 300 and 1,000 kilogrammes of 60
degrees Baumé per twenty-four hours. The condensation of anhydrous
sulphuric acid would pay, according to estimates submitted by Herr
Hasenclever; but to pass the gases through a tower filled with lime,
in order to get rid of the remaining sulphurous acid, would prove too
expensive at Stolberg. An attempt to use milk of lime proved partially
successful; but it was not followed up, because it was decided to
experiment with the process suggested by Prof. Cl. Winkler, of Freiberg,
who proposes to pass the gases through a tower filled with iron in
some suitable shape, over which water trickles. From the solution thus
obtained, sulphurous acid pure enough to be used for the manufacture
of sulphuric acid, sulphur, and a solution of green vitriol is made.
Experiments with this process are making at Freiberg and at the Rhenania
Works, near Stolberg. The trouble with the majority of methods thus
far is, that the draught of the furnaces is so much impeded by the
absorption towers that fans, blowers, or steam jets must be used to
carry the gases through it.

The experience of Herr Hasenclever has proved how difficult it is to
find a satisfactory means of removing the noxious vapors from furnace
gases without incurring too serious an expense. Thus far the value of
the products obtained by absorption of sulphurous acid has not been
equal to the cost of producing them. Herr C. Landsberg, who is general
manager of the Stolberg Company, has had similar experience, though his
experiments were made to test methods suggested at various times by Dr.
E. Jacob and Dr. Aarland. Both are very ingenious, and were successful
on a small scale, but failed when tried in actual working.--_Engineering
and Mining Journal_.

       *       *       *       *       *




NEW GAS EXHAUSTER.


In common practice, the new exhauster at the Old Kent Road passes
about five million cubic feet of gas per day of twenty-four hours, and
requires the attention of two men and two boys for driving and stoking,
at the following cost:

                                     s.  d.
Wages--2 men,  at 5s. 6d             11  0
Wages--2 boys, at 3s. 6d              7  0
                                     -----
                                 £ 0 18  0
Oil, 1 gallon                      0  3  6
Waste, 5 lb                        0  1  0
                                  --------
Total                            £ 1  2  6

for five million cubic feet, or 0.054d. per 1,000 feet. The boiler
burns a mixture of coke and breeze, chiefly the latter, of small value,
costing 0.0174d. per 1,000 feet of gas exhausted; therefore the total
cost of exhausting gas by the new system is--

Fuel                         0.0174d
Wages, oil, and waste        0.0540
                             --------
Total                        0.07l4d.

per 1,000 cubic feet of gas, exclusive of repairs, which will be
decidedly less for the new exhauster than for that on the older system,
from the friction being so much less. The feed water evaporated is at
the rate of about 7.4 lb. per pound of breeze, and 7.5 lb. per pound of
coke.

[Illustration: IMPROVED GAS EXHAUSTER.]

It will be seen that the exhausting arrangements at the Old Kent Road
are extremely economical, the cost of fuel being reduced to a minimum;
while a man and boy by day, and their reliefs for the night, attend to
the machinery inside the exhauster-house, and also to the pumps outside,
and stoke the boiler as well.--_Journal of Gas Lighting_.

       *       *       *       *       *




ADVANCE IN THE PRICE OF GLYCERINE


The continued advance in the price of glycerine continues to excite
comment among those who deal in or use it, and no one seems to know
exactly where or when the advance is likely to stop, or by what means a
retrograde movement will probably be brought about.

As we have heretofore stated, the rise has been brought about by a
combination of two causes--a falling off in production and a great
increase in the demand, owing to the discovery of new uses for it, and
the extension of the branches of manufactures in which it has been
heretofore employed.

In pharmacy, it is coming more and more into use daily, and in various
other branches of manufacture the same tendency is observable. It
has proved itself so elegant and so convenient a vehicle for the
administration of various medicinal substances, is so easily miscible
with both water and alcohol, and is so pleasant to the taste, that it
seems almost a wonder that it should have been so long in attaining the
rank among the articles of the _Materia Medica_ which it now occupies.
The two manufactures, however, which seem to lead in the demand for
glycerine are of nitro-glycerine and of oleomargarine.

The uses to which it is put for the former are well known, but precisely
what the latter could want of the article is not, at first glance,
quite so obvious. We are informed, however, that it is valued for its
antiseptic properties, and also for its softening effect on the _quasi_
butter. Be this as it may, it seems that both here and in Europe the
makers of these two articles are buying largely of both crude and
refined glycerine.

So it appears that the willingness of the people to eat artificial
butter, and the progress in schemes for internal improvement, such as
the De Lesseps Canal, for instance, to say nothing of the European
revolutionists, are responsible to a great extent for the scarcity of an
important article of pharmaceutical use.

On the other hand, while there is a notable increase in the demand for
the article, there is a gradual but very sure and noticeable falling off
in the production.

At present the supply for the whole world comes from the candlemakers
of Europe--chiefly France and Germany--and, as improved methods of
illumination push candles out of the drawing rooms of the wealthier as
well as the cabins of the poor, and consequently out of the markets, the
production of glycerine naturally grows less. In France, for instance,
candles are coming to be regarded among the wealthy chiefly as articles
of luxury, and are lighted only for display at festivals of especial
magnificence and ceremony, while among the poor the kerosene lamp is
coming into almost as universal use as here.

To be sure, the inexorable inn-keeper still keeps up, we believe, the
inevitable _bougie_, but even that is fast becoming more of a fiction
than ever. Even in the churches, it is said, the use of candles is
gradually falling off. To these causes must be attributed the decreasing
supply of the crude material, but it may be doubted whether this
decrease would be sufficient to materially affect the price for some
time to come were it not for the increased demand for the two industries
to which we have alluded. Obviously, there must be found eventually some
substitute for glycerine, or else some new source from which it may be
procured. The natural place to look for this would be in the waste
lye from the soapmakers' boilers, but so far no one has succeeded in
obtaining from this substance the glycerine it undoubtedly contains by
any process sufficiently cheap to allow of its profitable employment.

We are assured by a veteran soap-boiler who has experimented much in
this direction that it is impossible to recover a marketable article of
glycerine from the lees of soap in which resin is an ingredient. In his
words, it "kills the glycerine," and, as none but a few of the finest
soaps are now made without resin, it would seem that the search for
glycerine in this direction must be a hopeless one. It is a curious
commentary in the present state of affairs that previous to about 1857,
when candles were largely manufactured in this country, there was little
or no demand for glycerine, and millions of pounds of it were run
into the sewers. Even then, however, the use of it as a wholesome and
pleasant article of diet was known to the workmen employed in the candle
factories, who were accustomed to drink freely of the mingled glycerine
and water which constituted the waste from the candles. Yet with this
fact under their noses, as it were, it is only recently that members of
the medical profession have begun to recommend the same use of glycerine
as a substitute for cod liver oil.--_Pharmacist_.

       *       *       *       *       *




ANALYSIS OF OILS, OR MIXTURES OF OILS, USED FOR LUBRICATING PURPOSES.


Oils, fats, waxes, and bodies somewhat similar in nature, may--according
to the substance of a paper recently read before the Chemical Society,
by Mr. A. H. Allen, of Sheffield, and Mr. Thomson, of Manchester--be
divided into two great classes, viz., those which combine with soda,
potash, or other alkalies to form soaps, and those which do not; and
as those two classes of bodies differ materially in their actions on
substances such as iron, copper, etc., with which they come in contact,
it often becomes a question of great importance to the users of oils
for lubricating purposes to know what proportions of these different
substances are contained in any oil or mixture of oils. The object of
the authors was to give accurate methods for determining the percentages
of these bodies contained in any sample. Hydrocarbon or mineral oils are
now much used for lubricating the cylinders of engines, and especially
of condensing engines, and that for two reasons--first, because they are
neutral bodies, which have no action on metals; and, second, that they
are not liable to deposit on the boilers, if they should happen to be
introduced with the condensed water so as to produce burning of the
ironwork over the flues.

Animal or vegetable oils or fats are composed of fatty acids in
combination with glycerine, and these, under the influence of
high-pressure steam, are decomposed or dissociated, the fatty acids
being liberated from the glycerine, leaving the former to act upon or
corrode the iron of the cylinder. But here their objectionable influence
does not end. They form with the iron hard, insoluble compounds called
iron soaps, which increase the friction between the cylinder and piston,
and in some cases gradually collect into the form of hard balls inside
the cylinder.

When the water is used over and over again a considerable proportion of
the fatty acids of the oils used for lubricating the piston is carried
over with the steam and is found in the condensed water which is
introduced into the boiler along with the water. Here it commences
action, which proves quite as injurious to the boiler as it does to the
cylinder, but in a different way. It acts upon the iron of the boiler
and on some of the lime salts which constitute the incrustation, forming
greasy iron and lime soaps, which prevent the water from coming into
absolute contact with it. Thus the heat cannot be drawn away quickly
enough by the water, and the plates thus coated above the flues are
liable to become burdened and weakened. This action has in many cases
gone on to such an extent that the flues have collapsed under the
pressure of the steam inside.

The authors give two different processes for the determination of animal
or vegetable oils or fats and hydrocarbon or other neutral oils. They
take a certain weight of the sample and boil it with twice its weight
of an eight per cent, solution of caustic soda in alcohol. The soda
combines with the fatty acids of the animal or vegetable oils forming
soaps; bicarbonate of soda is then added to neutralize the excess of
caustic soda; and, lastly, sand; and the whole is evaporated to dryness
at the temperature of boiling water. The dry mixture is then transferred
to a large glass tube, having a small hole in the bottom plugged with
glass wool to act as a filter, and light petroleum spirit--which boils
at about 150° to 180° Fahr.--is poured over it, till all the neutral or
unsaponifiable oil is dissolved out. In the other process no sand is
used, but the dry mixture is dissolved in water, and the soap solution
which holds the neutral oils in solution is treated with ether, which
dissolves out the neutral oil and then floats to the surface of the
liquid. The ether solution is then drawn off, and the ether in the one
case and petroleum spirit in the other are separated from the dissolved
oils by distillation, the last traces of these volatile liquids being
separated by blowing a current of filtered air through the flask
containing the neutral oil, which is then weighed and its percentage on
the original sample calculated.

All animal and vegetable oils yield a small quantity--about one per
cent.--of unsaponifiable fatty matter, which must be deducted from the
result obtained. Sperm oil, however, was found to be an exception,
because from its peculiar chemical constitution it yields nearly half
its weight of a greasy substance to the ether or to the petroleum
spirit. The substance, however, dissolved from sperm oil after
saponification has the appearance of jelly, when the ether or petroleum
spirit solution is concentrated and allowed to cool, and the presence of
sperm oil can thus be readily detected. Solid paraffin, heavy petroleum
or paraffin oils, and rosin oil--which is produced by the destructive
distillation of rosin--are not saponifiable, and yield about the whole
of the amount employed to the petroleum spirit or ether. Japan wax is
almost entirely saponifiable, while beeswax and spermaceti yield about
half their weights to the petroleum spirit or ether.

       *       *       *       *       *




NITRITE OF AMYL.


Dr. Edgar Kurtz, of Florence, has found this medicament so useful in the
various aches and pains of every-day life that he has persuaded many
families of his acquaintance to keep it on hand as a domestic remedy. It
is an excellent external application for stomach-ache, colic, tooth ache
(whether nervous or arising from caries), neuralgia of the trigeminus,
of the cervico-brachial plexus, etc. It is superior to anything else
when inhaled in so-called angio-spastic hemicrania, giving rapid relief
in the individual paroxysms and prolonging the intervals between the
latter. No trial was made in cases of angio paralytic hemicrania, since
in this affection the drug would be physiologically contraindicated. It
has a very good effect in dysmenorrhoea, especially when occurring in
chlorotic girls; in mild cases external applications suffice, otherwise
the drug should be inhaled (when complicated with inflammatory
conditions of the uterus or appendages the results were doubtful or
negative). Its physiological action being that of a paralyzing agent of
the muscular tissue of the blood vessels, with consequent dilatation of
their caliber (most marked in the upper half of the body), nitrite of
amyl is theoretically indicated in all conditions of cerebral anaemia.
Practically it was found to be of much value in attacks of dizziness and
faintness occurring in anæmic individuals, as also in a fainting-fit
from renal colic, and in several cases of collapse during anaesthesia by
chloroform.

It has been recommended in asphyxia from drowning, hanging, and in
asphyxia of the new born, but the first indication in these cases is the
induction of artificial respiration, after the successful initiation of
which inhalations of nitrite of amyl doubtless assist in overcoming the
concomitant spasm of the smaller arteries.

One of the most important indications for the use of the drug is
threatening paralysis of the heart from insufficient compensation. In
such cases it is necessary to gain time until digitalis and alcoholics
can unfold their action, and here nitrite of amyl stands pre-eminent. A
single case in point will suffice to illustrate this. The patient was
suffering from mitral insufficiency, with irregular pulse, loss of
appetite, enlargement of the liver, and mild jaundice. Temporary relief
had been several times afforded by infusion of digitalis. In February,
1879, the condition of the patient suddenly became aggravated. The pulse
became very irregular and intermittent. The condition described as
delirium cordis presented itself, together with epigastric pulsation
and vomiting. Vigorous counter-irritation, by means of hot bottles
and sinapisms to the extremities, etc., proved useless. Digitalis and
champagne, when administered, were immediately vomited. The pulse ran up
from seventy until it could no longer be counted at the wrist, while
the beats of the heart increased to one hundred and twenty and more per
minute. The extremities grew cold, and the face became covered with
perspiration. The urine was highly albuminous. Nitrite of amyl was then
administered by inhalation: at first, three to five drops; then, ten to
twenty; and finally, more or less was poured on the handkerchief without
being measured. During each inhalation the condition of the patient
rapidly improved, but as quickly grew worse, so that the drug was
continued at short intervals all night, ten grammes in all having been
used. In the morning the patient was better, and 0.5 gramme of digitalis
was then given in infusion per rectum, and repeated on the following
day, after which the patient remained comparatively well until a year
and a half later, when a second attack of the kind just described was
quickly cut short by similar treatment.

Another noteworthy case was that of a robust man of thirty years, who
was attacked with acute gastro intestinal catarrh. The patient had
as many as one hundred watery evacuations in forty-eight hours, with
fainting fits, violent cramps in the calves of the legs, two attacks
of general convulsions--in short, he presented the picture of a person
attacked with cholera. Opium, champagne, hypodermic injections of
sulphuric ether, counter-irritation, etc., proved useless. The doctor
was on the point of injecting dilute liquor ammonii into the veins, but,
none being obtainable, it occurred to him to try nitrite of amyl as a
last resort. A considerable amount was poured on a handkerchief and held
before the patient's mouth and nose, while the legs were also rubbed
energetically with the same agent. Respiration soon became deeper and
more regular, while the pulse gradually returned at the wrist. These
procedures were repeated again and again, without regard to the quantity
of the drug used, as soon as the radial pulse became weaker, and kept
up until the patient complained of a sense of fullness in the head, and
requested the discontinuance of the drug. The evacuations became less
frequent, and in a week the patient was able to be up. Resuming then,
Kurz concludes that nitrite of amyl is indicated in cardiac affections
when the capillary circulation is obstructed and the cardiac muscle is
threatened with paralysis from overwork; further, in cases of impeded
circulation occasioned by cholera or severe diarrhea, particularly in
the so-called hydrocephaloid (false hydrocephalus) of children. It
is worthy of trial in tetanic and eclamptic seizures, and in tonic
angiospasms such as occur during the chill of malarial fevers, although
in the last-mentioned condition pilocarpine is perhaps more suitable,
provided the energy of the heart be unimpaired.

As regards the dose, Kurz's experience demonstrates that we need not
restrict ourselves to a few drops. The quantity may be increased, if
necessary, until symptoms of cerebral congestion show themselves, when
the drug should be momentarily or permanently discontinued. Usually from
three to five or ten drops are sufficient, sometimes even less. Kurz has
met with no unpleasant consequences, much less serious complications,
from the application of nitrite of amyl. But the drug is contraindicated
in cases associated with cerebral hyperaemia, in atheromatous conditions
of the arteries, and in the so-called plethoric state--_Beta's
Memoabilien, March 24, 1881_.

       *       *       *       *       *




THE TREATMENT OF ACUTE RHEUMATISM.

By ALFRED STILLÉ, M.D.


The treatment of simple acute articular rheumatism may be abandoned to
palliatives and nature. Apart from complications, such cases nearly
always recover under rest and careful nursing. Try and disabuse
yourselves of the idea that their cure is dependent upon medicines
alone; to help nature is often the best we can do. No treatment was ever
invented which stopped a case of acute articular rheumatism. It cannot
be stopped by bleeding, or sweating, or purging, by niter, by tartar
emetic, by guaiacum, by alkalies, by salines, by salicylic acid, or by
anything else. The physician can palliate the pain and perhaps shorten
the attack, can control and perhaps prevent complications and stiffness
of the joints, but he cannot arrest the disease. Where rest, proper
diet, and warmth are enjoined, most cases will get well just as soon
without as with the use of medicinal methods. Dr. Austin Flint, Sr.,
of New York, in support of this statement, subjected some patients, a
number of years ago, to the expectant treatment, and found that they
made just as rapid and just as complete recoveries as did those cases
under the most active medication. Purgatives have been used in all ages
in the treatment of this disease, because it was thought to be a fever.
We are all but too ready to put our necks into the yoke of a theory. In
old times they thought that the system ought to be reduced. Before the
time of purgatives depletion was employed. This mode of treatment I will
not even discuss. There is no evidence of which I am cognizant in favor
of purgatives. There are very good reasons indeed why they should not be
used: (1) Because they cannot possibly cure; (2) because they oblige the
patient to make painful movements; and (3) because they expose him to
the dangers of cold. A celebrated London physician had all his patients
packed in blankets, and did not allow them to move a finger. This was
going to the other extreme. There are certain cases in which purgatives
are alleged to be of use, viz.: Those in which the bowels are
constipated, and there is a bitter taste in the mouth. I have never seen
such cases except in habitual drunkards, and in such cases a purgative
does more harm than allowing the effete matter to remain in the system.
Opium was once vaunted as a specific, and it was claimed that it
diminished the tendency to complications in the course of the disease.
Dr. Corrigan, of Dublin, said that large doses of opium were well
borne--say from four to twelve grains in the course of twenty-four
hours, or sometimes he advised giving as much as one grain every hour.
Opium so employed does not produce narcotism, and does not constipate
the bowels. More recent experience has shown that opium, of all
remedies, is the most likely to cause heart complications. Some have
recommended colchicum, arguing that because it does good in gout, it
must, therefore, do good in rheumatism. But colchicum is not a remedy
for rheumatism. Many years ago it was very much the custom to administer
large doses of powdered Peruvian bark. The rationale of these large
doses was founded upon their sedative effect. Haygrath, Morton,
Heberden, and Fothergill were the first to employ this method. Later
still, a number of noted French physicians, among them Briquet, Andral,
Monerat, and Legroux, renewed the use of this medicine in the form of
quinia, but gave it in smaller doses, seeking only its tonic effect,
from five to fifteen grains being administered in the course of
twenty-four hours, and then it was still continued in smaller doses.
Still more recently, quinia taking the place of Peruvian bark, the old
plan of administering large doses has been resumed. From thirty all the
way up to one hundred grains have been administered in the course of
twenty-four hours. Never was there a more profligate waste of a precious
medicine. Even the physicians who so used it were obliged to acknowledge
that it only did good in sub-acute and mild cases. I believe that it has
also been fashionable in the so called cases of hyperpyrexia to immerse
the patient in a bath varying in temperature from 60° to 98° Fahr.
Although patients thus treated sometimes recovered, they also sometimes
perished from congestion of the lungs and brain.

Among cardiac and nervous sedatives, digitalis, veratrum album and
viride, veratria and aconite, have each, at one time or other, been
employed indiscriminately. Such treatment, of course, has only proven
itself to be a monument of rashness to those who employed it. Such
sedatives may reduce the pulse, but do not shorten the disease. Indeed,
if it is possible to prove the absurdity of anything more clearly by
mere enumeration of these medicines as cures for rheumatism, I do not
know of it. Do digitalis and aconite act in the same manner? This is
just one expression of the folly which surrounded the use of digitalis
at the time of its discovery. Then every affection of the heart was
treated with digitalis.

Within the last few years new remedies have been proclaimed in the shape
of salicylic acid and its sodium salt. I confess that I possess no
personal knowledge of their use in this disease, for I was at first
dissuaded from employing them by a prejudice against the grounds on
which they were recommended, and more recently by the contradictory
judgments respecting them, and the unquestionable mischief they have
sometimes caused. According to their eulogists, the arrest of the
disease is secured by them within four or five days, whether the attack
be febrile or not; its mortality was diminished; relapses do not occur
if the medicine is continued until full convalescence; it is without
influence on the heart complications already existing, but it tends
to prevent them as well as other serious inflammations. One of these
gentlemen assures us that to say it far excels any other method of
treatment would be to give it but scant praise. But, upon the other
hand, it is accused of producing disorders, and even grave accidents in
almost all the functions of the economy. In some cases it has produced
ringing in the ears or deafness, or a rapid pulse, or an excessively
high temperature, panting respiration, profuse perspiration,
albuminuria, delirium, and imminent collapse. In one published case this
anti-pyretic did not lower, but, on the contrary, seemed actually to
raise the temperature so high that immediately after death it stood at
110° F. Many, very many, analogous cases have been published. I repeat,
therefore, that I am personally unacquainted with the effects of this
medicine in acute articular rheumatism, and that I have not thus far
been tempted to employ it.

It may be difficult to see the connection between blisters and alkalies
in their power to influence the course of acute articular rheumatism,
and yet it is certain that they do so influence it, and in the same way,
_i. e._, by altering the condition of the blood from acid to alkaline.
If you ask me to explain to you how blisters act in this way I am
obliged to confess my ignorance. To produce this result they must be
applied over all the affected joints. Experience, if not science, has
decided conclusively in their favor. They do effect a cessation of the
local symptoms, render the urine alkaline, and diminish the amount of
fibrin in the blood.

This brings us to a consideration of the use of alkalies. Alkalies
neutralize the acids, act as diuretics, and eliminate the _materies
morbi_. Alone, and in small doses, they are unable to influence the
course of the disease; but when given in very large doses their effects
are marvelous; the pulse falls, the urine is increased in quantity and
becomes alkaline, and the inflammation subsides. The symptoms of the
disease are moderated, the duration of the attack is shortened, and the
cardiac complications are prevented. The dose of the alkalies must
be increased until the acid secretions are neutralized. A very good
combination of these remedies is the following:

Rx. Sodae bicarb              3 iss.
    Potas. acet               3 ss.
    Acid. cit              f. 3 ss.
    Aquae                  f. 3 ij. [1]

[Transcribers note 1: Could also be '2/3 ij.']

S. This dose should be repeated every three or four hours, until the
urine becomes alkaline. On the subsidence of the active symptoms two
grains of quinine may be added with advantage to each dose. The alkalies
must be gradually discontinued, but the quinia continued. The diet
should consist of beef tea or broth, with bread and milk; no solid food
should be allowed. Woolen cloths, moistened with alkaline solutions, may
with advantage be applied to the affected joints. To these laudanum
may be added for its anodyne effect. The patient must be sedulously
protected from vicissitudes of the temperature and be in bed between
blankets. The alkaline treatment relieves the pain, abates the fever,
and saves the heart by lessening the amount of fibrin in the blood. A
long time ago Dr. Owen Rees, of London, introduced the use of lemon
juice. This remedy was thought to convert uric acid into urea, and to
so help elimination. Though the treatment is practically correct, the
theory of it is all wrong. Lemon juice does good in mild cases, but
cannot be relied upon in severe attacks. During the febrile stage of
acute articular rheumatism the diet should consist mainly of farinaceous
and mucilaginous preparations, with lemonade and carbonic acid water as
drinks. The cloths applied to the joints should be changed when they
become saturated with sweat, and in changing them the patient should be
protected from the air. The sweating may be controlled by small doses
of atropia, from the one-sixtieth to the one-thirtieth of a grain. To
prevent subsequent stiffness the joints should be bathed with warm oil
and chloroform, and wrapped in flannel cloths. In the proper season this
condition is very well treated by sea-bathing. There is no specific plan
of treatment in acute articular rheumatism. The treatment pursued
must vary according to the intensity of the inflammation and the
peculiarities of the patients.--_Medical Gazette_.

       *       *       *       *       *




METHOD IN MADNESS.


No psychologist has hitherto been able, and probably it is impossible,
to define _madness_, or to give a clearly marked indication of the
boundary line between sanity and insanity. Mental soundness is merged
in unsoundness by degrees of decadence which are so small as to be
practically inappreciable. It is with the mind-state which precedes the
development of recognized form of insanity the therapeutist and the
social philosopher are chiefly interested. Although in individual cases
the subject of mental derangement may, as the phrase runs, "go mad"
suddenly, speaking generally insanity is a symptom occurring in the
course of disease, and, commonly, not until the malady of which it is
the expression has made some progress. Those mental disturbances which
consist in a temporary aberration of brain function, and which are the
accidents of instability, rather than the effects of developed or even
developing neuroses, can scarcely be classed as insanity; although it is
true, and in an important sense, that these passing storms of excitement
or spells of moody depression may--acting reflexly on the cerebral and
nervous centers, as all mind-states and mind-movements react--exert a
morbific influence and lay the physical bases of mental disease. The
consideration most practical to the community and germane to the
question of public safety is, that in any and every population there
must exist a dangerously large proportion of persons who are always in
a condition of mind to be injuriously influenced by any force which
powerfully affects them. As a matter of history, it would seem that the
majority of such persons are controlled rather than morbidly excited by
the opportunity of throwing themselves into any popular movement. They
may suffer afterward for the stimulation they receive at the time of
public commotions, but while these are in progress they link their own
consciousness with that of other minds, and the tendency to develop
individual eccentricities of mental action is thereby for the moment
repressed or exhausted. It is in the intervals of great public
excitement the peace is disturbed by the vagaries of criminals who are
more or less reasonably suspected of being "insane."

It would be premature to assume that the murderer of Mr. Gold, or the
man who attempted to assassinate the President of the United States of
America, is insane. There are circumstances in connection with each of
these tragedies which must suggest the reflection that the assailants
were possibly, or even probably, of unsound mind. We do not, however,
propose to discuss these features of the respective cases at this
juncture. The full facts are not, as yet, ascertained; but enough is
known to warrant an endeavor to clear the way for future remark by
disposing of the objection that the suspected perpetrator of the
Brighton outrage and the would-be assassin of the President both showed
"forethought" and "method." It is a common formula for the expression of
doubt as to the irresponsibility of an alleged lunatic, that there is
"method in his madness." Nothing can be farther from the truth than the
inference to which this observation is intended to point. It is not in
the least degree necessary that a madman should be unconscious of the
act he performs, or of its nature as a violation of the law of God
or man; nor is it necessary that he should do the deed under an
ungovernable impulse, or at the supposed bidding of God or devil, angel
or fiend. The forms of mental disease to which these presumptions apply
are coarse developments of insanity. Dr. Prichard was among the first of
English medico-psychologists to recognize the existence of a more subtle
form of disease, which he termed "moral insanity." Herbert Spencer
supplied the key-note to this mystery of madness when he propounded the
doctrine of "dissolution;" and Dr. Hughlings Jackson has since applied
that hypothesis to the elucidation of morbid mental states and their
correlated phenomena. When disorganizing--or, if we may borrow
an expression from the terminology of geological science,
_denuding_--disease attacks the mental organism, it, so to say, strips
off, layer by layer, the successive strata of "habit," "principle," and
"nature," which compose the character. First in order go the higher
moral qualities of the mind; next those which are the result of
personally formed habits; then the inherited principles of personal and
social life; at length the polish which civilization gives to humanity
is lost, and in the process of denudation the evolutionary elements of
man's nature are progressively destroyed, until he is reduced to the
level of a creature inspired by purely animal passions, and obeying the
lower brutish instincts. The term "moral insanity" is accurate as far
as it goes, but it expresses only the first stage in a process of
dissolution which is essentially the same throughout, but which has
unfortunately received different designations as its several features
have been recognized and studied apart. The difference between the
subject of "moral insanity" and the general paralytic, who has lost all
sense of decency and lives the life of a beast, is one of degree. The
practical difficulty is to convince the mere observer that forms of
insanity which seem to consist in the loss of moral qualities and
principles _only_, may be as directly the effect of brain disease as any
of those grosser varieties of mental disorder which he is perfectly well
able to recognize, and fully prepared to ascribe to their proper cause.

To the professional mind, at least, it will follow from what we have
said that the injury to mind properties or qualities inflicted by the
invasion of disease may be partial, and must in every case be determined
by laws or conditions governing the progress of disease, perhaps on
the lines and in the directions which have been least well guarded by
educationary influences. A man may lose his faculty of forming a wise
judgment long before he is deprived of the power of distinguishing
between right and wrong. This is so because it is a higher attainment in
moral culture to do right advisedly, than simply to perceive the right
thing to do. The application of principle to conduct is an advance on
the mere recognition of virtue in the concrete, or even the possession
of virtue in the abstract. The question whether any past act of
wrongdoing was an act of insanity does not so much depend upon the great
question whether the person doing it was insane as a whole being, or
whether the deed done was the outcome of passion or error, the direct
fruit of limited or special disease. In short, the insanity of the act
must be inferred from the morbid condition of the brain from which it
sprang, rather than from the act itself. A partially disorganized--or as
we prefer to say "denuded"--brain may be fully capable of sane thought,
except on some one topic, and able to exercise every intellectual
function except of a particular order. Or there may be mental weakness
and neurotic susceptibility in regard to a special class of impressions.
It would be difficult to name any form of act or submission which may
not be the outcome of incipient or limited disease. The practical
difficulty is to avoid, on the other hand, treating the fruits of
disease as willful offenses; while, on the other, we do not allow the
supposition or presumption of disease to be employed as an excuse for
wrongdoing. It is, of course, clear that there may be perfect method in
such madness as springs from partial or commencing brain disease; for
every element in the mental process which culminates in a mad act may be
sane except the inception of the idea in which the act took its rise.
Thus, in the case of the suspected murderer of Mr. Gold, there may have
been perfect sanity in respect to every stage of the process by which
the crime was planned and carried out, and yet insanity, the effect of
brain disease, in the idea by which the deed was suggested. For example,
when a man is suffering from morbid suspicion, and, fixing his distrust
on some individual, purposes to murder him, the intellectual processes
by which he lays his plans and fulfills his morbidly conceived
intention, are performed with perfect sanity, as by a sane will. It is
important to recognize this. There is no difference in _nature_ between
the mental operation by which a "sane" man contrives and executes a
crime, and that by which a known "lunatic" will commit the like offense.
There may be as much _method_ in the one instance as in the other, and
the faculties which exhibit this method may be as sound and effective,
but in the one case the idea behind the act is sane, while in the other
it is insane. The brain is not one large homogeneous organ to be
healthy or diseased, orderly or deranged, throughout at any one period.
Inflammations, and diseases generally, which affect the brain as a whole
do not commonly cause insanity properly so called. The organ of the
mind is a composite, or aggregate of cells, or molecules, any number
or series of which may be affected with disease while the rest remain
healthy. At present we are only on the threshold of investigation
concerning the physical causes of insanity, and have scarcely done more
than recognize the possibility of _molecular_ disease of the brain.
Hereafter science will, probably, succeed in unveiling the obscure facts
of molecular brain pathology, and enable the medical psychologist to
predicate disease of recognized classes of brain elements from the
special phenomena of mind disturbance. This is the line of inquiry, and
the result, to which the progress already made distinctly tends. For the
present, the inferences we can surely draw from known facts are
very few; but prominent among the number are certain which it is
all-important to recognize in view of the judgment which must hereafter
be formed on the two cases now engaging public attention on both sides
of the Atlantic. The existence of method in madness is no marvel, and
that characteristic cannot therefore be supposed, or alleged, to weigh
as evidence against the "insanity" of the criminal. The perpetrators of
these heinous offenses against common right and public safety may be
more or less responsible for their acts, and, so far as these are
concerned, more or less sane or insane. The measure of the morbid
element in their individual cases will be the health or disease of the
particular part or element of the brain from which the offense sprang.
The ultimate judgment formed must be determined upon the basis of
scientific tests to be applied to the action of the brain alleged to be
the subject of partial or incipient disease. There is nothing in the
facts as they stand to supply the materials for a judgment. Precise
scientific inquiry can alone solve the enigma each case presents.

       *       *       *       *       *




SIMPLE METHODS TO STAUNCH ACCIDENTAL HEMORRHAGE.

By EDWARD BORCK, M.D., St. Louis, Mo.


At first sight it seems almost superfluous to write or say a word about
any method of arresting hemorrhage from wounds; for the practitioner,
as a rule, is well acquainted with all the different manipulations and
appliances for the purpose, and enough may be obtained from the text
books. Nevertheless, to call attention to some useful, or old, or
apparently forgotten matter occasionally, seems not to be amiss, for it
refreshes our memory, stimulates us to think about and keeps before
our eyes important subjects. A few hints on the above, I hope, will
therefore be well received.

The treatment of hemorrhage, viz., the arresting of the same from open
wounds, is not only important to the surgeon as the basis of surgery,
but it is also of great importance to the laity, and especially to
those workmen who are perpetually in danger of being injured. It is
astonishing how unknowing the people seem to be, with any method to
check bleeding from a wound temporarily; even the most simple method of
pressure is in the majority of such accidents not resorted to. The sight
of a little blood does not alone upset a timid, nervous woman, but many
times the strongest of men; and why? because it naturally creates a
feeling of awe and detestation. If a person is wounded by a machine, or
otherwise, a crowd of all his fellow workmen gather around him, and look
on the poor fellow bleeding; half a dozen or more will start out on a
run in different directions to hunt a doctor, or some old woman who has
a reputation for stopping bleeding by sympathy, either of whom they are
likely to find "not at home." In the meantime the vital fluid trickles
away; nobody knows what to do; everybody does something, but none the
right thing. Now, it is true, it does not often happen that any one
bleeds to death, wise mother nature, as a rule, coming to their
assistance, especially in lacerated wounds; but the anemic condition
produced by excessive loss of blood is followed by severe consequences,
and is to be dreaded, for it retards recovery. To save all the blood
possible ought to be apprehended as an important matter by every one.

Hardly a week passes that some unfortunate is not brought to my office,
who has been badly injured in some way; he has been bleeding, perhaps,
the distance of several blocks, and arrives almost faint. In the most of
such cases they have something tied around their wounds, but hardly ever
in any manner so as to be equal to stop the bleeding. In exceptional
cases you find a tourniquet or the Spanish windlass applied. This,
when applied by a surgeon, may answer very well, but when applied by a
non-professional person it is invariably screwed up so tight that the
pain produced thereby is so great and intolerable that the patient
prefers rather to bleed to death. This is a great objection.

Therefore I will call attention to the method of forcible flexion; and
though extreme flexion has been practiced by surgeons in isolated cases,
still to Professor Adelman, of Dorpat, is due the credit of first having
systematized the following method:


BLEEDING FROM THE UPPER ARM (ART. BRACHIALIS).

Bring the elbows of the patient as near as possible together upon the
back, and fasten them with a bandage. From this point let a doppelt
bandage pass down to and over the perineum; separate the bandages again
in front, let one end run over the left, the other over the right groin
back again to the elbows (see Fig. 1)

[Illustration: Fig. 1.]

"The illustrations will explain at a glance."


BLEEDING FROM THE ARTERIES IN THE UPPER THIRD OF THE ARM.

Acute flexion of the elbow, simple bending of the forearm upon the upper
arm, will suffice. But if there is bleeding from the arteries near the
joint of the hand or from any part of the hand, then the hand must also
be brought into flexion, and secured by a bandage. (See Fig. 2.) The
bandage must always be wrapped around the wound first.

[Illustration: Fig. 2.]


BLEEDING FROM THE THIGH (ART. FEMORALIS).

It needs no other explanation, as Fig. 3 shows the mode of stopping the
hemorrhage from that region temporarily.

Bleeding from the front part of the leg (Art. Tibialis Ant.), same as
Fig. 3.

[Illustration: FIG. 3.]

Bleeding from the posterior part of the leg (Art. Tibiailis Post, et
Peronea) same as above, with the addition of a tampon or compress under
the knee joint, or like Fig. 4.


BLEEDING FROM THE FOOT (ART. PLANTARIS ET DORSALIS PEDIS).

Flexion of the leg upon the thigh, and flexion of the foot upon the
front of the tibia.

Objections might also be raised to the above method on account of the
pain which it may produce; but the flexion never needs to be so forced
as to be unendurable to the patient; the position may be a little
uncomfortable to a very sensitive person, that is all. Furthermore, it
has been proven that a limb can be kept in a flexed position for several
days, "nine by some authors," without any injury, and with a complete
closure of the arteries. We do not expect, however, that this method of
arresting hemorrhage will ever be adopted as "the" method in surgery,
neither will it be necessary here to point out any cases where the
practitioner can have and under certain circumstances be obliged to have
to resort to this simple method. Military surgeons may also profit by
it, for it is certainly a valuable and admirable mode, and so easily
applied in cases of emergency by any one, if the unfortunate should be
distant from surgical aid. I also believe that it would be advisable and
certainly humane, to instruct the people in general, by popular lectures
or through the press, the manner of stopping hemorrhage temporarily.

[Illustration: Fig. 4.]

The simplest of all methods, however, to arrest hemorrhage is the
rubber bandage. It has displaced in surgery the old tourniquet almost
completely, which required a certain skill and anatomical knowledge to
apply it; not necessarily so with the rubber bandage. Any one can apply
it, for the amount of pressure needed to arrest the hemorrhage from a
wound suggests itself. The rubber bandage produces but little pain; the
patient is comparatively comfortable and out of immediate danger and
anxiety; while in the meantime the proper attention can be secured.

I think it would be well if our health officers would direct their
attention a little to the accidental hemorrhages, and if they do not
possess the power, to refer the matter to the proper tribunal to enact
a law that would compel all owners and corporations of factories, saw,
planing, and rolling mills, and, in fact, every establishment where
the laborers are constantly in danger of accidents, to keep on hand a
certain number of strong rubber bandages, according to the number of
men employed, and that at least several of the men, if not all in every
establishment of that kind, be instructed in the application of the
bandage. Steamboats and other vessels should carry a supply, and
railroad companies should be obliged to furnish all watchmen along their
respective roads with rubber bandages, and see that the men know how to
use them in case an accident should occur. Every train that goes out
should have some bandages on board in care of some employe, who knows
how to handle them when needed. Many pounds of precious blood may thus
be saved, and danger to life from this cause be averted.--_Indiana
Medical Reporter_.

       *       *       *       *       *




HOT WATER COMPRESSES IN TETANUS AND TRISMUS.


Sporer has successfully treated cases of tetanus by merely applying to
the nape of the neck and along the spine large pieces of flannel dipped
in hot water, of a temperature just bearable to the hand (50-55°
C.).--_Allg. med. cent. Zeit_., January 15, 1881.

       *       *       *       *       *




TRIALS OF STRING SHEAF BINDERS AT DERBY, ENGLAND.


After a week's postponement, rendered necessary by the unripe condition
of the crops on the first of the month, the trials of sheaf-binding
machines, using any other binding material than wire, instituted by the
Royal Agricultural Society of England, began on Monday morning, the 8th
of August. By nine o'clock, the time appointed for beginning operations,
there was a very large number of gentlemen interested in these trials
already collected on the farm of Mr. Hall, at Thulston, and the
distances that many of them had come testified to the importance of the
interests involved. The morning was perfect for reaping, though
ominous clouds in the southwest led many to hazard conjectures, which
unfortunately turned out too well founded, that the Royal Agricultural
Society would not on this occasion escape the fate which had visited
them so often. The corn stood ripe and upright in the various plots into
which the fields had been divided, and the ground was level and dry. The
published list of the competitors contained twenty entries, not by as
many firms, however, for many names appeared more than once; but the
rules of the society, which objects to different machines being used for
different kinds of corn in these trials, together with non-attendance
for unknown reasons, had reduced the actual list of competing machines
to seven. These were as follows: Mr. W. A. Wood, the McCormick
Harvesting Machine Company, the Johnston Harvester Company, Messrs.
Samuelson & Company, Messrs. J. & F. Howard, Messrs. Aultman & Company,
and Mr. H.J.H. King. All these machines were to be seen at the show,
except the second named, which was delayed by the stranding of
the steamship Britannic, and had only lately arrived in rather a
weather-beaten condition. The trials were to be made upon oats, barley,
and wheat, and the plots for the preliminary trials were about half an
acre in extent. Shortly after half-past nine o'clock, the judges and
engineers of the society having arrived upon the ground, a start was
made upon the oats by the three machines belonging to Mr. Wood, Messrs.
Samuelson & Co., and the Johnston Harvester Company. It should, perhaps,
be mentioned that the strength of this crop of oats varied a good deal
in different parts of the field. These three machines all belong to the
class which has the automatic trip--that is, the binding gear is thrown
into action by the pressure of the straw accumulated arriving at a
certain value, independently of any special action on the part of the
driver. The sheaves from Messrs. Samuelson's machines were extremely
neat and well separated from each other, a point to which farmers attach
great importance.

It would appear that it is impossible to secure the binding of every
single sheaf. Here and there, even with the best binders, an occasional
miss will occur, in which the corn is thrown out unbound. However, with
Messrs Samuelson's machine this was extremely rare, and the neatness of
the sheaves produced was remarkable. No doubt the shortness of the crop
in the portion allotted to this machine may have had something to do
with this, as a longer straw is more likely than a shorter one to
connect two sheaves and produce that hanging together which in other
machines is so often observed to precede a miss in the binding. Mr.
Wood's machine had a stronger crop and longer straw to deal with, and
the hanging together of the sheaves occurred far too frequently, and was
almost always followed by a loose sheaf. The Johnston harvester went
through a very fair performance; there was no hanging except at turning
the corners, and the piece of work was finished in a shorter time than
with the other machines. Notwithstanding the automatic character of the
gear for binding, we believe it will be found that the sheaves produced
in these machines vary very much in weight.

At about 10:20 the next lot of machines started. They were those of
the McCormick Harvesting Machine Company, Messrs. Howard, and Messrs.
Aultman & Co. Of these, the first-named only has the automatic trip. We
believe it made no miss in binding during this trial, and the sheaves
were neat, though, perhaps, rather too tightly bound. There was no
hanging together or check in this run. The machine of Messrs. Aultman &
Co. was not so successful in separating the sheaves, though this was
not so often followed by an unbound sheaf as in some other machines.
Sometimes as many as three sheaves, clinging closely together, were
ejected at one time. To avoid this a man walked by the machine, and
assisted the delivery of the sheaf. The tension of the string which
binds the sheaves varies a good deal in this machine, some of the
sheaves being rather too loosely held together, while at other times the
fault is in the other direction. In Messrs. Howard's machine there is a
tendency in the sheaves to cling together, but this is not accompanied
to any extent with missing the binding. Mr. King attempted a run after
the three last had finished their plots; but his machinery had not been
fully adjusted, and after one course the trial stopped. As far as one
could judge from this short performance, the chief fault in the sheaf
produced was the uncertain position of the string upon it. Sometimes
this was near the bottom of the straw, and sometimes among the corn.
Unfortunately at 11:25 the rain began, and experiments were stopped till
the afternoon. It was no light shower which could give a check to the
ardor of the judges and other officers of the society, but a heavy
downpour of some hours' duration, which soaked the crop through and
through. Indeed, we think it a pity that the experiments should have
been continued at all under circumstances in which practical harvesting
would have been out of the question. However, after a short lull in the
rain, the machines of Mr. Wood, Messrs. Samuelson, and the McCormick
Harvesting Company went into the wet barley. The machine of Mr. Wood
worked most rapidly, but the clinging of the sheaves and the failure to
bind were again very apparent. The stubble left by this machine was the
shortest and most even of the three. The machines of Messrs. Samuelson
and the McCormick Company left a very ragged, long, and uneven stubble
in this trial, though the delivery and binding of the sheaves seemed to
be as good as in the oats trial. The binding in the former was rather
too tight.

The remaining machines, with the exception of that of Mr. King, then
attempted a trial; but Messrs. Howard's machine having too smooth a
face to the driving wheel, was unable to drive all the gear in the wet
condition of the ground. The damp weather had no doubt tightened up the
canvas carriers, and thereby added to the work to be done; but this was
the only machine that was found incapacitated through the action of
the rain. Unfortunately the plots assigned to this machine and to the
Johnston harvester were in juxtaposition, so that the latter machine
was blocked by the former, and could not proceed, and that of Messrs.
Aultman alone went through with its work. There was no improvement in
the separation of the sheaves, and the misses were rather more frequent
than in the trials among the oats. The sheaves, too, that issued singly
were somewhat wanting in neatness. The whole of these barley trials must
be looked upon as unsatisfactory, on account of the condition of the
crop, and it is to be hoped that before the investigations are brought
to a conclusion all these machines may have a more favorable opportunity
of demonstrating the advantages which are claimed for them. It may be
here said that throughout these trials there has been as yet no wind
at all, which, as the investigations are in other respects to be so
thoroughly carried out, is a matter of regret. Probably Messrs. Howard's
machine was as well protected from the wind as any other of the seven
competitors.

The following are the awards of the judges, which were made known
on Wednesday evening: Gold medal--Messrs. McCormick & Co. Silver
medals--Messrs. Samuelson, Messrs. Johnston & Co. Highly commended--Mr.
H. J. King, for principle of tying and separating sheaves. The only
gleaning binding machine which entered the field was that of Mr. J. G.
Walker, made by the Notts Fork Company, but no official trials of this
were made.--_The Engineer_.

       *       *       *       *       *




THE CULTURE OF STRAWBERRIES.


Messrs. Ellwanger & Barry, of the Mount Hope Nurseries, at Rochester,
give the following directions for setting out and cultivating
strawberries, the result of long and successful experience, in their
recently issued Strawberry Catalogue:

_The Soil and Its Preparation_.--The strawberry may be successfully
grown in any soil adapted to the growth of ordinary field or garden
crops. The ground should be _well_ prepared, by trenching or plowing at
least eighteen to twenty inches deep, and be _properly enriched_ as for
any garden crop. It is unnecessary to say that if the land is wet, it
must be thoroughly drained.

_Season for Transplanting_.--In the Northern States, the season for
planting in the spring is during the months of April and May. It may
then be done with safety from the time the plants begin to grow until
they are in blossom. This is the time we prefer for setting out _large
plantations_.

During the months of August and September, when the weather is usually
hot and dry, _pot-grown_ plants may be planted to the best advantage.
With the ball of earth attached to the roots, they can be transplanted
without any failures, and the trouble and annoyance of watering,
shading, etc., which are indispensable to the success of layer plants,
are thus in a great measure avoided.


GARDEN CULTURE.

_To Cultivate the Strawberry_.--For family use, we recommend planting
in beds four feet wide, with an alley two feet wide between. These beds
will accommodate three rows of plants, which may stand fifteen inches
apart each way, and the outside row nine inches from the alley. These
beds can be kept clean, and the fruit can be gathered from them without
setting the feet upon them.

_Culture in Hills_.--This is the best mode that can be adopted for the
garden. If you desire fine, large, high-flavored fruit, pinch off the
runners as fast as they appear, repeating the operation as often as may
be necessary during the summer. Every runner thus removed produces a new
crown at the center of the plant, and in the fall the plants will have
formed large bushes or stools, on which the finest strawberries may be
expected the following season. In the meantime, the ground among the
plants should be kept clear of weeds, and frequently stirred with a hoe
or fork.

_Covering in Winter_.--Where the winters are severe, with little snow
for protection, a slight covering of leaves or litter, or the branches
of evergreens, will be of great service. This covering should not be
placed over the plants till after the ground is frozen, usually from the
middle of November till the first of December in this locality. Fatal
errors are often made by putting on _too much_ and _too early_. Care
must also be taken to remove the covering in spring just as soon as the
plants begin to grow.

_Mulching to Keep the Fruit Clean_.--Before the fruit begins to ripen,
mulch the ground among the plants with short hay or straw, or grass
mowings from the lawn, or anything of that sort. This will not only keep
the fruit clean, but will prevent the ground from drying and baking, and
thus lengthen the fruiting season. Tan-bark can also be used as a mulch.

A bed managed in this way will give two full crops, and should then be
spaded or plowed down, a new one having been in the meantime prepared to
take its place.


FIELD CULTURE.

The same directions with regard to soil, time of planting, protection,
and mulching, as given above, are applicable when planting on a large
scale.

_The Matted Row System_.--The mode of growing usually pursued has its
advantages for field culture, but cannot be recommended for the garden.
In the field we usually plant in rows three to four feet apart, and the
plants a foot to a foot and a half apart in the row. In this case much
of the labor is performed with the horse and cultivator.

_How to Ascertain the Number of Plants Required for an Acre_.--The
number of plants required for an acre, at any given distance apart, may
be ascertained by dividing the number of square feet in an acre (43,560)
by the number of square feet given to each plant, which is obtained
by multiplying the distance between rows by the distance between the
plants. Thus strawberries planted three feet by one foot give each plant
three square feet, or 14,520 plants to the acre.

       *       *       *       *       *




SOME HARDY FLOWERS FOR MIDSUMMER.


Pretentious gardens are now gayly decorated with glowing masses
of pelargoniums and vincas, belts of rich coleuses and fiery
alternantheras, patchwork of feverfew and mesembryanthemum, and
scroll-work of house leeks, but amid this gay checkering it is wonderful
how few flowers there are for cutting for bouquets. As tender plants,
except the few that may have been wintered in windows and cellars, are
beyond the reach of most of our country folks, I will consider those
only that are perfectly hardy and in full blossom now, July 21.

Koempfer's irises, blue, white, purple, streaked, marbled, and otherwise
variegated, are in bloom; they are the grandest of their race, and as
different varieties succeed one another, they may be had in bloom
from June till August. They are easily raised from seed or by
division--prefer rich, moist land, and if in a partly shaded place,
their blossoms last longer than in full sunshine.

Trumpet lilies are bursting into bloom; the scarlet martagon is at its
best; _speciosum_, tiger, and American Turk's cap lilies are yet to
follow. I find the trumpet lilies have done better this year than any of
the other sorts in open places. Most of the yellow day lilies are past,
but the tawny one is at its best; they are all hardy, and seem to thrive
alike in wild or cultivated land. Seibold's funkia (called also day
lily) has pale bluish flowers, and large, handsome glaucous leaves: the
undulated-leaved funkia has beautifully variegated leaves, and pale
bluish blossoms; these, together with several others of their race,
are in bloom. They like to grow in undisturbed clumps in rich and
faintly-shaded nooks; if grown in full sunshine they bloom well enough,
but their leaves get "scorched."

The European meadow sweet (_Spiraea ulmaria_), two feet high, and the
Kamtchatka one, four feet high, are in bloom; the double varieties are
far finer, whiter, and more lasting than the single ones. They will grow
anywhere. There are many fine kinds of sedum or liveforever in season;
some of them like _album_ (white), _pulchellum_ (pink), _spurium
splendens_ (pink), _hispanicum_ (white), may more properly be called
stonecups, but the stronger-growing sorts, as _S. warscewiczii_
(yellow), should be regarded as liveforevers. They like open, sunny
places, and dislike artificial waterings.

_Dicentra eximia_ (pink-purple) is free, neat, copious, and a perpetual
bloomer, as is also _Corydalis lutea_ (yellow). The climbing fumitory
comes up of itself from seed every year, and is now running over bushes,
stakes, and strings, and is full of fern-like leaves and flesh-colored
flowers. The long, scarlet wands of _Pentstemon barbatus_ are
conspicuous in the borders; this should be in every garden, it is so
profuse and hardy. Many speedwells still remain in fine condition,
notably _Veronica longifolia;_ they are a hardy and a showy race of
plants, and will grow anywhere. The main lot of perennial larkspurs are
past, but by cutting them over now many flower spikes will be produced
during the fall months. The yucca or bear-grass is in perfection; its
massive flower scapes are very telling. It will grow anywhere, and once
established it is hard to get rid of.

Many kinds of perennial bell-flowers are in fine condition, as the
carpathian, peach-leaved (second crop), nettle-leaved, common harebell,
and vase harebell. In the case of many of the tall-growing kinds, better
results are obtained by treating them as biennials than perennials. No
garden should be without the double white feverfew; the more you cut it
the more it blooms. _Anthemis tinctoria_, yellow or white, the yellow is
by far the best, and the lance-leaved, large-flowered, larkspur-leaved
and eared coreopsises are fine, seasonable perennials, as are likewise
the yellow, white, and pink yarrows, double sneezewort, the cone
flowers, and large-flowered fleabanes, and all grow readily in
any ordinary garden soil, and with little care. Hollyhocks are in
perfection; feed them well and prevent many sprouts to each stool. Many
kinds of meadow rue, as garden plants, have a bold, graceful appearance;
they love moist soil.

In good soil and a partly shaded spot we have no handsomer plant in
bloom than the tall bugbane (_Cimicifuga racemosa_); from a bunch of
thrifty leaves arise a dozen scapes of racemes, creamy white, and six
feet high. The scarlet lychnis and its many varieties are nearly past,
but the large-flowered, Haag's, and others of that section, are in their
prime, and showy plants they are. They are true and lasting perennials,
bloom well the first season from seed, quite hardy, copious, and
effective; any ordinary garden soil. The pyrenean prunella has large
purple heads; the false dragonhead (_Physostegia_), pale rose-purple
spikes; centranthuses, cymes of red and white; centaureas, heads of
yellow, blue, and purple; pinks, divers shades of red and white; and
monkshoods, hoods of blue or white; and all are very hardy, ready
growers, and copious bloomers. The bee balm, one of our handsomest
perennials, has bright red whorls; it spreads upon the surface of the
ground like mint, and thus may be divided and increased to any extent.
It loves rich, moist land, but is not fastidious. Among the evening
primroses the Missouri one is the brightest and biggest; _speciosa_,
white, from Texas, of blossoms the most prolific; _glauca, riparia,
fruticera_, and _linearis_, all yellow; many others, though perennial,
are best treated as annual or biennial. The spiked loosestrife planted
by the water's edge of a pond is far finer than in the garden border. It
has hundreds of red spikes.

Add to these, everlasting peas, musk mallows, spiderwort, globe
thistles, bold senecios, the finer milkweeds, _Scabiosa, Gallium_,
Chinese _Astilbe_, various kinds of loosestrife (_Lysimachia_), and many
others as perennials, and _Coreopsis_, balsams, zinnias, marigolds,
stocks, Swan river daisy, mignonnette, sweet peas, sweet alyssum,
morning glories, larkspurs, canary flowers, cucumber-leaved sunflowers,
verbenas, petunias, corn flower, Drummond phlox, double and single
poppies, snapdragons, _Phacelia, Gilia, Clarkia_, candytuft, red flax,
tassel flowers, blue _Anchusa, Gaillardia_, and a multitude besides of
seasonable annuals, which can all be raised quite easily without a frame
or green-house, and what excuse has any farmer for having a flowerless
garden in midsummer?--_William Falconer, in Country Gentleman_.

       *       *       *       *       *




THE TIME-CONSUMING MATCH.


Mr. Edward Prince, splint manufacturer, of Horseshoe Bay, Buckingham
township, is authority for the statement that there are about twenty-two
match factories in the United States and Canada, and that the daily
production--and consequent daily consumption--is about twenty-five
thousand gross per day. It may seem a queer statement to make that one
hundred thousand hours of each successive day are spent by the people of
the two countries in striking a light, but such is undoubtedly the case.
In each gross of matches manufactured there are 144 boxes, so that the
25,000 gross produces 3,600,000 boxes. Each box, at least those made
in the States, where a duty of one cent upon every box of matches is
levied--contains 100 matches, so that the number of matches produced and
used daily amounts to 360,000,000. Counting that it takes a second to
light each match--and it is questionable whether it can be done in less
time than that, while some men occupy several minutes sometimes in
trying to strike a light, particularly when boozy--to light the
360,000,000 would take just that number of seconds. This gives 6,000,000
minutes, or 100,000 hours. In days of twenty-four hours each it figures
up to 4,166 2-3, and gives eleven years and five months with a couple of
days extra, as the time occupied during every twenty-four hours, by
the people of North America--not figuring on the Mexicans--in striking
matches. Figuring a little further it gives 4,159 years time in
each year. The fact may seem amazing, but it is undoubtedly quite
correct.--_Ottawa Free Press_.

       *       *       *       *       *

A catalogue, containing brief notices of many important scientific
papers heretofore published in the SUPPLEMENT, may be had gratis at this
office.

       *       *       *       *       *




THE SCIENTIFIC AMERICAN SUPPLEMENT.

PUBLISHED WEEKLY.

TERMS OF SUBSCRIPTION, $5 A YEAR.


Sent by mail, postage prepaid, to subscribers in any part of the United
States or Canada. Six dollars a year, sent, prepaid, to any foreign
country.

All the back numbers of THE SUPPLEMENT, from the commencement, January
1, 1876, can be had. Price, 10 cents each.

All the back volumes of THE SUPPLEMENT can likewise be supplied. Two
volumes are issued yearly. Price of each volume, $2.50, stitched in
paper, or $3.50, bound in stiff covers.

COMBINED RATES--One copy of SCIENTIFIC AMERICAN and one copy of
SCIENTIFIC AMERICAN SUPPLEMENT, one year, postpaid, $7.00.

A liberal discount to booksellers, news agents, and canvassers.

MUNN & CO., PUBLISHERS,

37 PARK ROW, NEW YORK, N. Y.

       *       *       *       *       *




PATENTS.


In connection with the SCIENTIFIC AMERICAN, Messrs. MUNN & Co. are
Solicitors of American and Foreign Patents, have had 35 years'
experience, and now have the largest establishment in the world. Patents
are obtained on the best terms.

A special notice is made in the SCIENTIFIC AMERICAN of all Inventions
patented through this Agency, with the name and residence of the
Patentee. By the immense circulation thus given, public attention is
directed to the merits of the new patent, and sales or introduction
often easily effected.

Any person who has made a new discovery or invention can ascertain, free
of charge, whether a patent can probably be obtained, by writing to MUNN
& Co.

We also send free our Hand Book about the Patent Laws, Patents, Caveats.
Trade Marks, their costs, and how procured, with hints for procuring
advances on inventions. Address

MUNN & CO., 37 PARK ROW, NEW YORK.

Branch Office, cor. F and 7th Sts., Washington, D. C.










End of Project Gutenberg's Scientific American Supplement No. 299, by Various