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THE "HOW-TO-DO-IT" BOOKS

PRACTICAL MECHANICS FOR BOYS




THE "HOW-TO-DO-IT" BOOKS

PRACTICAL MECHANICS
FOR BOYS

In language which every boy can understand
and so arranged that he may readily carry
out any work from the instructions given.

WITH MANY ORIGINAL ILLUSTRATIONS

By J. S. ZERBE, M.E.

_Author of_

CARPENTRY FOR BOYS
ELECTRICITY FOR BOYS


M. A. DONOHUE & COMPANY

CHICAGO :: NEW YORK

COPYRIGHT, 1914, BY
THE NEW YORK BOOK COMPANY

Made in U. S. A.




CONTENTS


INTRODUCTORY                                                    Page 1

I. ON TOOLS GENERALLY                                           Page 7

 Varied Requirements. List of Tools. Swivel Vises. Parts of Lathe.
 Chisels. Grinding Apparatus. Large Machines. Chucks. Bench Tools.
 Selecting a Lathe. Combination Square. Micrometers. Protractors.
 Utilizing Bevel Protractors. Truing Grindstones. Sets of Tools. The
 Work Bench. The Proper Dimensions. How Arranged.

II. HOW TO GRIND AND SHARPEN TOOLS                             Page 26

 Importance of the Cutting Tool. The Grinder. Correct Use of Grinder.
 Lathe Bitts. Roughing Tools. The Clearance. The Cutting Angle. Drills.
 Wrong Grinding. Chisels. Cold Chisels. System in Work. Wrong Use of
 Tools.

III. SETTING AND HOLDING TOOLS                                 Page 34

 Lathe Speed. The Hack-saw. Hack-saw Frame. The Blade. Files.
 Grindstones. Emery and Grinding Wheels. Carelessness in Holding Tools.
 Calipers. Care in Use of Calipers. Machine Bitts. The Proper Angle for
 Lathe Tools. Setting the Bitt. The Setting Angle. Bad Practice. Proper
 Lathe Speeds. Boring Tools on Lathe. The Rake of the Drill. Laps. Using
 the Lap. Surface Gages. Uses of the Surface Gage.

IV. ON THE FIRST USE OF THE FILE                               Page 48

 The First Test. Filing an Irregular Block. Filing a Bar Straight.
 Filing Bar with Parallel Sides. Surfacing Off Disks. True Surfacing.
 Precision Tools. Test of the Mechanic. Test Suggestions. Use of the
 Dividers. Cutting a Key-way. Key-way Difficulties. Filing Metal Round.
 Kinds of Files. Cotter-file. Square. Pinion. Half-round. Round.
 Triangular. Equalizing. Cross. Slitting. Character of File Tooth.
 Double Cut. Float-cut. Rasp Cut. Holding the File. Injuring Files.
 Drawing Back the File.

V. HOW TO COMMENCE WORK                                        Page 61

 Familiarity with Tools. File Practice. Using the Dividers. Finding
 Centers. Hack-saw Practice. Cutting Metal True. Lathe Work. First
 Steps. Setting the Tool. Metals Used. The Four Important Things.
 Turning Up a Cylinder. Turning Grooves. Disks. Lathe Speeds.

VI. ILLUSTRATING SOME OF THE FUNDAMENTAL DEVICES               Page 68

 Belt Lacing. Gears. Crown Wheel. Grooved Friction Gearing. A Valve
 which Closes by the Water Pressure. Cone Pulleys. Universal Joint.
 Trammel for Making Ellipses. Escapements. Simple Device to Prevent a
 Wheel or Shaft from Turning Back. Racks and Pinions. Mutilated Gears.
 Simple Shaft Coupling. Clutches. Ball and Socket Joints. Tripping
 Devices. Anchor Bolt. Lazy Tongs. Disk Shears. Wabble Saw. Crank Motion
 by a Slotted Yoke. Continuous Feed by Motion of a Lever. Crank Motion.
 Ratchet Head. Bench Clamp. Helico-volute Spring. Double helico-volute.
 Helical Spring. Single Volute Helix Spring. Flat Spiral, or Convolute.
 Eccentric Rod and Strap. Anti-dead Center for Lathe.

VII. PROPERTIES OF MATERIALS                                   Page 79

 Elasticity. Traction. Torsion. Flexure. Tenacity. The Most Tenacious
 Metal. Ductility. Malleability. Hardness. Alloys. Resistance.
 Persistence. Conductivity. Equalization. Reciprocity. Molecular Forces.
 Attraction. Cohesion. Adhesion. Affinity. Porosity. Compressibility.
 Elasticity. Inertia. Momentum. Weight. Centripetal Force. Centrifugal
 Force. Capillary Attraction. The Sap of Trees. Sound. Acoustics. Sound
 Mediums. Vibration. Velocity of Sound. Sound Reflections. Resonance.
 Echos. Speaking Trumpet. The Stethoscope. The Vitascope. The
 Phonautograph. The Phonograph. Light. The Corpuscular Theory.
 Undulatory Theory. Luminous Bodies. Velocity of Light. Reflection.
 Refraction. Colors. The Spectroscope. The Rainbow. Heat. Expansion.

VIII. HOW DRAUGHTING BECOMES A VALUABLE AID                    Page 95

 Lines in Drawing. Shading. Direction of Shade. Perspectives. The Most
 Pronounced Lines. Direction of Light. Scale Drawings. Degree, and What
 it Means. Memorizing Angles. Section Lining. Making Ellipses and
 Irregular Curves. Focal Points. Isometric and Perspective. The
 Protractor. Suggestions in Drawing. Holding the Pen. Inks. Tracing
 Cloth. Detail Paper. How to Proceed. Indicating Material by Section
 Lines.

IX. TREATMENT AND USE OF METALS                               Page 112

 Annealing. Toughness and Elasticity. The Process. Tempering. Tempering
 Contrasted with Annealing. Materials Used. Gradual Tempering. Fluxing.
 Uniting Metals. Alloying Method. Welding. Sweating. Welding Compounds.
 Oxidation. Soldering. Soft Solder. Hard Solder. Spelter. Soldering
 Acid. The Soldering Iron.

X. ON GEARING, AND HOW ORDERED                                Page 121

 Spur and Pinion. Measuring a Gear. Pitch. Diametral Pitch. Circular
 Pitch. How to Order a Gear. Bevel and Miter Gears. Drawing Gears.
 Sprocket Wheels.

XI. MECHANICAL POWER                                          Page 128

 The Lever. Wrong Inferences from Use of Lever. The Lever Principle.
 Powers vs. Distance Traveled. Power vs. Loss of Time. Wrongly-Directed
 Energy. The Lever and the Pulley. Sources of Power. Water Power.
 Calculating Fuel Energy. The Pressure or Head. Fuels. Power from Winds.
 Speed of Wind and Pressure. Varying Degrees of Pressure. Power from
 Waves and Tides. A Profitable Field.

XII. ON MEASURES                                              Page 139

 Horse Power. Foot Pounds. Energy. How to Find Out the Power Developed.
 The Test. Calculations. The Foot Measure. Weight. The Gallon. The
 Metric System. Basis of Measurement. Metrical Table, Showing
 Measurements in Feet and Inches.

XIII. USEFUL INFORMATION FOR THE WORKSHOP                     Page 148

 Finding the Circumference of a Circle. Diameter of a Circle. Area of a
 Circle. Area of a Triangle. Surface of a Ball. Solidity of a Sphere.
 Contents of a Cone. Capacity of a Pipe. Capacity of Tanks. To Toughen
 Aluminum. Amalgams. Prevent Boiler Scaling. Diamond Test. Making Glue
 Insoluble in Water. Taking Glaze Out of Grindstone. To Find Speeds of
 Pulleys. To Find the Diameters Required. To Prevent Belts from
 Slipping. Removing Boiler Scale. Gold Bronze. Cleaning Rusted Utensils.
 To Prevent Plaster of Paris from Setting Quickly. The Measurement of
 Liquids with Spoons.

XIV. SIMPLICITY OF GREAT INVENTIONS AND OF NATURE'S MANIFESTATION
                                                              Page 152

 Invention Precedes Science. Simplicity in Inventions.
 The Telegraph. Telephone. Transmitter. Phonograph.
 Wireless Telegraphy. Printing Telegraph. Electric Motor.
 Explosions. Vibrations in Nature. Qualities of
 Sound. The Photographer's Plate. Quadruplex Telegraphy.
 Electric Harmony. Odors. Odophone. A Bouquet
 of Vibrations. Taste. Color.

XV. WORKSHOP RECIPES AND FORMULAS                             Page 160

 Adhesives for Various Uses. Belt Glue. Cements. Transparent Cement. U.
 S. Government Gum. To Make Different Alloys. Bell-metal. Brass.
 Bronzes. Boiler Compounds. Celluloid. Clay Mixture for Forges. Modeling
 Clay. Fluids for Cleaning Clothes, Furniture, etc. Disinfectants.
 Deodorants. Emery for Lapping Purposes. Explosives. Fulminates. Files,
 and How to Keep Clean. Renewing Files. Fire-proof Materials or
 Substances. Floor Dressings. Stains. Foot Powders. Frost Bites. Glass.
 To Frost. How to Distinguish. Iron and Steel. To Soften Castings.
 Lacquers. For Aluminum and Brass. Copper. Lubricants. Paper.
 Photography. Plasters. Plating, Coloring Metals. Polishes. Putty. Rust
 Preventives. Solders. Soldering Fluxes. Steel Tempering. Varnishes.
 Sealing Wax.

XVI. HANDY TABLES                                             Page 178

 Table of Weights for Round and Square Steel. Table of Weight of Flat
 Steel Bars. Avoirdupois Weight. Troy Weight. Apothecaries' Weight.
 Linear Measure. Long Measure. Square Measure. Solid or Cubic Measure.
 Dry Measure. Liquid Measure. Paper Measure. Table of Temperatures.
 Strength of Various Metals. Freezing Mixtures. Ignition Temperatures.
 Power and Heat Equivalents.

XVII. INVENTIONS AND PATENTS, AND INFORMATION ABOUT THE
      RIGHTS AND DUTIES OF INVENTORS AND WORKMEN,
                                                              Page 188

 The Machinist's Opportunities. What is an Inventor? Idea Not Invention.
 What an Invention Must Have. Obligation of the Model Builder. Paying
 for Developing Devices. Time for Filing an Application. Selling an
 Unpatented Invention. Joint Inventors. Joint Owners Not Partners.
 Partnerships in Patents. Form of Protection Issued by the Government.
 Life of a Patent. Interference Proceedings. Concurrent Applications.
 Granting Interference. Steps in Interference. First Sketches. First
 Model. First Operative Machine. Preliminary Statements. Proving
 Invention. What Patents Are Issued For. Owner's Rights. Divided and
 Undivided Patents. Assignments. How Made. What an Invention Must Have.
 Basis for Granting Patent in the United States. Reasons for Granting
 Abroad. Original Grants of Patents. International Agreement.
 Application for Patents. Course of Procedure. Costs. Filing a Matter of
 Secrecy.




LIST OF ILLUSTRATIONS

  FIG.                                                            PAGE
   1. Bench vise                                                     8
   2. Pipe grip for vise                                             9
   3. Swivel vise                                                   10
   4. Speed lathe                                                   11
   5. Calipers                                                      12
   6. Engine lathe                                                  13
   7. Center gage                                                   14
   8. Pocket screw and wire gage                                    15
   9. Handy bench vise                                              16
  10. Combination square                                            17
  11. Uses of the combination square                                18
  12. A quick adjusting micrometer                                  19
  13. Universal bevel protractor                                    20
  14. Uses of universal bevel protractor                            21
  15. Grindstone truing device                                      22
  16. Set of tools and case                                         23
  17. The work bench                                                24
  18. Hook tool                                                     28
  19. Parting tool                                                  28
  20. Knife tool                                                    28
  21. Right-hand side tool                                          28
  22. Internal tool                                                 28
  23. Left-hand side tool                                           28
  24. Tool for wrought iron                                         29
  25. Tool for cast iron                                            29
  26. End view of drill                                             31
  27. Side view of drill                                            31
  28. Hack-saw frame                                                35
  29. Hack-saw blade                                                35
  30. Plain hook tool                                               38
  31. Plain straight tool                                           38
  32. Proper angles for tools                                       39
  33. Angles for tools                                              39
  34. Angles for tools                                              39
  35. Set of the bitt                                               40
  36. Correct angle                                                 41
  37. Wrong angle                                                   41
  38. Too low                                                       42
  39. Improper set                                                  42
  40. Internal set                                                  43
  41. Set for brass                                                 43
  42. Surface gage                                                  44
  43. Uses of surface gage                                          46
  44. Rounded surface                                               49
  45. Winding surface                                               49
  46. Hexagon nut                                                   51
  47. Laying off hexagon nut                                        51
  48. Cutting key-way                                               52
  49. Key-seat rule                                                 54
  50. Filing metal round                                            54
  51. Filing metal round                                            54
  52. Making a round bearing                                        55
  53. Making a round bearing                                        55
  54. Cross section of file                                         56
  55. Files                                                         58
  56. Correct file movement                                         59
  57. Incorrect file movement                                       60
  58. Belt lacing                                                   69
  59. Belt lacing                                                   69
  60. Belt lacing                                                   69
  61. Belt lacing                                                   69
  62. Bevel gears                                                   71
  63. Miter gears                                                   71
  64. Crown wheel                                                   71
  65. Grooved friction gears                                        71
  66. Valve                                                         71
  67. Cone pulleys                                                  71
  68. Universal joint                                               71
  69. Trammel                                                       73
  70. Escapement                                                    73
  71. Device for holding wheel                                      73
  72. Rack and pinion                                               73
  73. Mutilated gears                                               73
  74. Shaft coupling                                                73
  75. Clutches                                                      75
  76. Ball and socket joints                                        75
  77. Fastening ball                                                75
  78. Tripping devices                                              75
  79. Anchor bolt                                                   75
  80. Lazy tongs                                                    75
  81. Disc shears                                                   75
  82. Wabble saw                                                    76
  83. Continuous crank motion                                       76
  84. Continues feed                                                76
  85. Crank motion                                                  76
  86. Ratchet head                                                  76
  87. Bench clamp                                                   76
  88. Helico-volute spring                                          77
  89. Double helico-volute                                          77
  90. Helical spring                                                77
  91. Single volute-helix                                           77
  92. Flat spiral or convolute                                      77
  93. Eccentric rod or strap                                        77
  94. Anti dead-centers for lathes                                  77
  95. Plain circle                                                  95
  96. Ring                                                          96
  97. Raised surface                                                96
  98. Sphere                                                        96
  99. Depressed surface                                             96
 100. Concave                                                       97
 101. Forms of cubical outlines                                     98
 102. Forms of cubical outlines                                     98
 103. Forms of cubical outlines                                     98
 104. Forms of cubical outlines                                     98
 105. Shading edges                                                 99
 106. Shading edges                                                 99
 107. Illustrating heavy lines                                     100
 108. Illustrating heavy lines                                     100
 109. Lines on plain surfaces                                      101
 110. Lines on plain surfaces                                      101
 111. Illustrating degrees                                         102
 112. Section lining                                               103
 113. Drawing an ellipse                                           104
 114. Perspective at angles                                        106
 115. Perspective of cube                                          107
 116. Perspective of cube                                          107
 117. Perspective of cube                                          107
 118. Protractor                                                   108
 119. Using the protractor                                         109
 120. Section-lining metals                                        110
 121. Spur gears                                                   122
 122. Miter gear pitch                                             123
 123. Bevel gears                                                  124
 124. Laying of miter gears                                        125
 125. Sprocket wheel                                               128
 126. Simple lever                                                 129
 127. Lever action                                                 130
 128. The pulley                                                   132
 129. Change of direction                                          133
 130. Change of direction                                          133
 131. Steam pressure                                               135
 132. Water pressure                                               135
 133. Prony brake                                                  141
 134. Speed indicator                                              142




PRACTICAL MECHANICS FOR BOYS




INTRODUCTORY


The American method of teaching the mechanical arts has some
disadvantages, as compared with the apprentice system followed in
England, and very largely on the continent.

It is too often the case that here a boy or a young man begins work in a
machine shop, not for the avowed purpose of learning the trade, but
simply as a helper, with no other object in view than to get his weekly
wages.

Abroad, the plan is one which, for various reasons, could not be
tolerated here. There he is bound for a certain term of years, and with
the prime object of teaching him to become an artisan. More often than
otherwise he pays for this privilege, and he knows it is incumbent on
him "to make good" right from the start.

He labors under the disadvantage, however, that he has a certain tenure,
and in that course he is not pushed forward from one step to the next on
account of any merit of his own. His advancement is fixed by the time he
has put in at each part of the work, and thus no note is taken of his
individuality.

Here the boy rises step after step by virtue of his own qualifications,
and we recognize that one boy has the capacity to learn faster than
another. If he can learn in one year what it requires three in another
to acquire, in order to do it as perfectly, it is an injury to the apt
workman to be held back and deterred from making his way upwardly.

It may be urged that the apprentice system instills thoroughness. This
may be true; but it also does another thing: It makes the man a mere
machine. The true workman is a thinker. He is ever on the alert to find
easier, quicker and more efficient means for doing certain work.

What is called "Efficiency" in labor methods, can never obtain in an
apprenticeship system for this reason. In a certain operation, where
twelve motions are required to do a certain thing, and a minute to
perform the twelve operations, a simplified way, necessitating only
eight motions, means a difference in saving one-third of the time. The
nineteen hundred fewer particular movements in a day's work, being a
less strain on the operator, both physically and mentally, to say
nothing whatever of the advantages which the proprietor of the shop
would gain.

I make this a leading text in the presentation of this book; namely,
that individual merit and stimulus is something of such extreme
importance that it should be made the keynote for every boy who tries to
become a mechanic.

The machinist easily occupies a leading place in the multitude of trades
and occupations. There is hardly an article of use but comes to the
market through his hands. His labor is most diverse, and in his
employment doing machine work he is called upon to do things which vary
widely in their character.

These require special knowledge, particular tools, and more frequently
than otherwise, a high order of inventive ability to enable him to
accomplish the task.

The boy should be taught, at the outset, that certain things must be
learned thoroughly, and that habits in a machine shop can be bad as well
as good. When he once becomes accustomed to putting a tool back in its
rightful place the moment he is through with it, he has taken a long
step toward efficiency.

When he grasps a tool and presents it to the work without turning it
over several times, or has acquired the knack of picking up the right
tool at the proper place, he is making strides in the direction of
becoming a rapid and skilled workman.

These, and many other things of like import, will require our attention
throughout the various chapters.

It is not the intention of the book to make every boy who reads and
studies it, a machinist; nor have we any desire to present a lot of
useful articles as samples of what to make. The object is to show the
boy what are the requirements necessary to make him a machinist; how to
hold, handle, sharpen and grind the various tools; the proper ones to
use for each particular character of work; how the various machines are
handled and cared for; the best materials to use; and suggest the
numerous things which can be done in a shop which will pave the way for
making his work pleasant as well as profitable.

It also analyzes the manner in which the job is laid out; how to set the
tools to get the most effective work; and explains what is meant by
making a finished piece of workmanship. These things, properly acquired,
each must determine in his own mind whether he is adapted to follow up
the work.

Over and above all, we shall try to give the boy some stimulus for his
work. Unless he takes an interest in what he is doing, he will never
become an artisan in the true sense of the word.

Go through the book, and see whether, here and there, you do not get
some glimpses of what it means to take a pleasure in doing each
particular thing, and you will find in every instance that it is a
satisfaction because you have learned to perform it with ease.

I do not know of anything which has done as much to advance the arts and
manufactures, during the last century, as the universal desire to
improve the form, shape and structure of tools; and the effort to invent
new ones. This finds its reflection everywhere in the production of new
and improved products.

In this particular I have been led to formulate a homely sentence which
expresses the idea: Invention consists in doing an old thing a new way;
or a new thing any way.

THE AUTHOR.




CHAPTER I

ON TOOLS GENERALLY


Judging from the favorable comments of educators, on the general
arrangement of the subject matter in the work on "Carpentry for Boys," I
am disposed to follow that plan in this book in so far as it pertains to
tools.

In this field, as in "Carpentry," I do not find any guide which is
adapted to teach the boy the fundamentals of mechanics. Writers usually
overlook the fact, that as the boy knows nothing whatever about the
subject, he could not be expected to know anything about tools.

To describe them gives a start in the education, but it is far short of
what is necessary for one in his condition. If he is told that the
chisel or bit for a lathe has a diamond point, or is round-nosed, and
must be ground at a certain angle, he naturally wants to know, as all
boys do, _why_ it should be at that angle.

So in the setting of the tools with relation to the work, the holding
and manipulation of the file, of the drill for accurate boring, together
with numerous little things, are all taken for granted, and the boy
blunders along with the ultimate object in sight, without having the
pathway cleared so he may readily reach the goal.

VARIED REQUIREMENTS.--The machinist's trade is one which requires the
most varied tools of all occupations, and they are by all odds the most
expensive to be found in the entire list of vocations.

[Illustration: _Fig. 1. Bench Vise._]

This arises from the fact that he must work with the most stubborn of
all materials. He finds resistance at every step in bringing forth a
product.

LIST OF TOOLS.--With a view of familiarizing the boy with this great
variety the following list is compiled, from which we shall select the
ones essential in the initial equipment of a small shop.

VISES.--One small, good vise is infinitely preferable to two bad ones.
For ordinary work a 3-inch jaw is preferable, and it should be firmly
mounted on the bench. So many kinds are now made that it would be a
costly thing to purchase one for each special use, therefore the boy
will find it profitable to make some attachments for the ordinary vise.

[Illustration: _Fig. 2. Pipe Grip for Vise._]

SWIVEL VISES.--A swivel vise is always a good tool, the cost being not
excessive over the ordinary kind. Then a pair of grips for holding pipe,
or round material which is to be threaded, can readily be made.

The drawing (Fig. 2) shows a serviceable pair of grips, made to fit the
jaws of a vise, and will be acceptable in much of the work. Then, the
vise should be provided with copper caps for the jaws to be used when
making up articles which would otherwise be injured by the jaws.

[Illustration: _Fig. 3. Swivel Vise._]

Let us get a comprehensive view of the different kinds of tools
necessary in a fully equipped shop.

PARTS OF LATHE.--The first thing of importance is the lathe, and of
these there is quite a variety, and among the accompaniments are the
slide rest, mandrel, back gear, division plate, angle plate, cone plate
and various chucks.

There must also be change wheels, studs and quadrant plates, self-acting
feed for surfacing and cross slide, and clamping nuts.

Drilling machines, both hand and power, hand and ratchet braces and
breast-drill stocks.

[Illustration: _Fig. 4--Speed Lathe._]

CHISELS.--Chisels of various kinds, for chipping and cross-cutting;
round-nosed, centering, set punches, tommies and drifts.

Back, tee and centering square; bevels, spirit level, inside and outside
calipers, straight edges, rules and surface plates.

Gages for boring, scribing blocks, steel and brass scribes, stocks and
dies, screw-plates, taps for bolts, reamers.

[Illustration: _Fig. 5. Calipers_]

Files for various descriptions, countersinks, frame and hack saws.

GRINDING APPARATUS.--Emery wheel, cloth and paper, paper, flour emery,
polishing powders, laps and buffs, and polishing sticks.

[Illustration: _Fig. 6. Engine Lathe._
 _A. Lathe Bed_
 _B. Rack Gear_
 _C. Live Center_
 _D. Dead Center_
 _E. Dead Spindle_
 _F. Face Plate_
 _G. Feed Screw_
 _H. Train of Gears_
 _I. Head Stock_
 _J. Mandrel_
 _K. Cone Pulley_
 _L. Angle Plate for Tool Holder_
 _M. Tool Post_
 _N. Tail Stock_
 _O. Wheel for Slide Rest Mechanism_
 _P. Locking Lever for Tail Stock._]

Forge, anvils, tongs, swages, punches, bolt tools, hot and cold chisels,
blow-pipe, soldering iron, hard and soft solders, borax, spirits of
salts, oil, resin and spelter.

To this may be added an endless variety of small bench tools,
micrometers, protractors, arbors, collets, box tools and scrapers.

[Illustration: _Fig. 7. Center Gage._]

LARGE MACHINES.--The list would not be complete without the planer,
shaper and milling machine, with their variety of chucks, clamps and
other attachments, too numerous to mention.

The foregoing show what a wonderful variety of articles are found in a
well-equipped shop, all of which can be conveniently used; but to the
boy who has only a small amount of money, a workable set is indicated as
follows:

A small lathe, with an 8-inch swing, can be obtained at a low cost,
provided with a countershaft complete.

CHUCKS.--With this should go a small chuck, and a face-plate for large
work, unless a large chuck can also be acquired. This, with a dozen
tools of various sizes, and also small bits for drilling purposes.

The lathe will answer all purposes for drilling, but small drilling
machines are now furnished at very low figures, and such a machine will
take off a great deal of duty from the lathe.

[Illustration: _Fig. 8. Pocket Screw and Wire Gage._]

As the lathe is of prime importance, never use it for drilling, if you
have a driller, as it always has enough work to do for tuning up work.

BENCH TOOLS.--Of bench tools, a 3-inch vise, various files, center
punch, two hammers, round and A-shaped peons, hack saw, compasses,
inside and outside calipers, screw driver, cold chisels, metal square,
level, straight edge, bevel square, reamers, small emery wheel and an
oil stone, make a fairly good outfit to start with, and these can be
added to from time to time.

Everything in the machine shop centers about the lathe. It is the king
of all tools. The shaper and planer may be most efficient for surfacing,
and the milling machine for making grooves and gears, or for general
cutting purposes, but the lathe possesses a range of work not possible
with either of the other tools, and for that reason should be selected
with great care.

[Illustration: _Fig. 9. Handy Bench Vise._]

SELECTING A LATHE.--The important things about a lathe are the spindle
bearings and the ways for the tool-holder. The least play in either will
ruin any work. Every other part may be defective, but with solidly
built bearing-posts and bearings, your lathe will be effective.

For this reason it will not pay to get a cheap tool. Better get a small,
6-inch approved tool of this kind, than a larger cheap article. It may
pay with other tools, but with a lathe never.

Never do grinding on a lathe. The fine emery, or grinding material, is
sure to reach the bearings; it matters not what care is exercised. There
is only one remedy for this--overhauling.

[Illustration: _Fig. 10.--Combination Square._]

COMBINATION SQUARE.--A tool of this kind is most essential, however
small. It can be used as a try-square, and has this advantage, that the
head can be made to slide along the rule and be clamped at any point. It
has a beveling and a leveling device, as well.

[Illustration: _Fig. 11.--Uses of the Combination Square._]

The combination square provides a means for doing a great variety of
work, as it combines the qualities of a rule, square, miter, depth gage,
height gage, level and center head.

[Illustration: _Fig. 12.--A Quick Adjusting Micrometer._]

The full page illustration (Fig. 11) shows some of the uses and the
particular manner of holding the tool.

MICROMETERS.--Tools of this description are made which will accurately
measure work in dimensions of ten-thousandths of an inch up to an inch.

The illustration (Fig. 12) shows an approved tool, and this is so
constructed that it can instantly be changed and set by merely pressing
the end of the plunger as shown.

[Illustration: _Fig. 13.--A Universal Bevel Protractor._]

PROTRACTORS.--As all angles are not obtainable by the square or bevel, a
protractor is a most desirable addition to the stock of tools. As one
side of the tool is flat it is convenient for laying on the paper when
drafting, as well as for use on the work.

The protractor has a graduated disk, and is adjustable so it can be
disposed at any angle.

[Illustration: _Fig. 14.--Universal Bevel Protractor, showing its
uses._]

All special tools of this kind are serviceable, and the boy should
understand their uses, even though he is not able for the time being to
acquire them. To learn how they are applied in daily use is an education
in itself.

UTILIZING BEVEL PROTRACTOR.--Examine the full-page illustration (Fig.
14), and see how the bevel protractor is utilized to measure the angles
of work, whether it is tapering heads or different kinds of nuts, or end
and side surfacing, and it will teach an important lesson.

[Illustration: _Fig. 15.--Grindstone Truing Device._]

TRUING GRINDSTONES.--Devices for truing up grindstones are now made, and
the illustration (Fig. 15) shows a very efficient machine for this
purpose. It can be applied instantly to the face of the stone, and it
works automatically, without interfering with the use of the stone.

It is frequently the case that an emery wheel will become glazed, due to
its extreme hardness. This is also caused, sometimes, by running it at
too high a speed. If the glazing continues after the speed is reduced,
it should be ground down an eighth of an inch or so. This will, usually,
remedy the defect.

[Illustration: _Fig. 16.--Set of Tools and Case._]

SETS OF TOOLS.--A cheap and convenient set of precision tools is shown
in Fig. 16, which is kept in a neat folding leather case. The set
consists of a 6-inch combination square, complete center punch, 6-inch
flexible steel rule center gage, 4-inch calipers, 4-inch outside caliper
with solid nut, 4-inch inside caliper with solid nut, and a 4-inch
divider with a solid nut.

[Illustration: _Fig. 17. The Work Bench._]

THE WORK BENCH.--This is the mechanic's fort. His capacity for work will
depend on its arrangement. To the boy this is particularly interesting,
and for his uses it should be made full three inches lower than the
standard height.

A good plan to judge of the proper height is to measure from the jaws of
the vise. The top of the jaw should be on a level with the elbows. Grasp
a file with both hands, and hold it as though in the act of filing
across the work; then measure up from the floor to the elbows, when they
are held in that position.

THE PROPER DIMENSIONS.--This plan will give you a sure means of
selecting a height that is best adapted for your work. The regulation
bench is about 38 inches high, and assuming that the vise projects up
about 4 inches more, would bring the top of the jaws about 42 to 44
inches from the floor. It is safe to fix the height of the bench at not
less than 34 inches.

This should have a drawer, preferably near the right-hand end of the
bench. The vise should be at the left side, and the bench in your front
should be free of any fixed tools.

HOW ARRANGED.--Have a rack above the bench at the rear, for the various
tools when not in use, and the rear board of the bench should be
elevated above the front planks several inches, on which the various
tools can be put, other than those which are suspended on the rack
above.

The advantage of this is, that a bench will accumulate a quantity of
material that the tools can hide in, and there is nothing more annoying
than to hunt over a lot of trash to get what is needed. It is necessary
to emphasize the necessity of always putting a tool back in its proper
place, immediately after using.




CHAPTER II

HOW TO GRIND AND SHARPEN TOOLS


It is singular, that with the immense variety of tools set forth in the
preceding chapter, how few, really, require the art of the workman to
grind and sharpen. If we take the lathe, the drilling machine, as well
as the shaper, planer, milling machine, and all power-driven tools, they
are merely mechanism contrived to handle some small, and, apparently,
inconsequential tool, which does the work on the material.

IMPORTANCE OF THE CUTTING TOOL.--But it is this very fact that makes the
preparation of that part of the mechanism so important. Here we have a
lathe, weighing a thousand pounds, worth hundreds of dollars,
concentrating its entire energies on a little bit, weighing eight
ounces, and worth less than a dollar. It may thus readily be seen that
it is the little bar of metal from which the small tool is made that
needs our care and attention.

This is particularly true of the expensive milling machines, where the
little saw, if not in perfect order, and not properly set, will not only
do improper work, but injure the machine itself. More lathes are ruined
from using badly ground tools than from any other cause.

In the whole line of tools which the machinist must take care of daily,
there is nothing as important as the lathe cutting-tool, and the
knowledge which goes with it to use the proper one.

Let us simplify the inquiry by considering them under the following
headings:

1. The grinder.

2. The grinding angle.

THE GRINDER.--The first mistake the novice will make, is to use the tool
on the grinder as though it were necessary to grind it down with a few
turns of the wheel. Haste is not conducive to proper sharpening. As the
wheel is of emery, corundum or other quickly cutting material, and is
always run at a high rate of speed, a great heat is evolved, which is
materially increased by pressure.

Pressure is injurious not so much to the wheel as to the tool itself.
The moment a tool becomes heated there is danger of destroying the
temper, and the edge, being the thinnest, is the most violently
affected. Hence it is desirable always to have a receptacle with water
handy, into which the tool can be plunged, during the process of
grinding down.

CORRECT USE OF GRINDER.--Treat the wheel as though it is a friend, and
not an enemy. Take advantage of its entire surface. Whenever you go into
a machine shop, look at the emery wheel. If you find it worn in creases,
and distorted in its circular outline, you can make up your mind that
there is some one there who has poor tools, because it is simply out of
the question to grind a tool correctly with such a wheel.

[Illustration: _Fig. 18. Hook Tool._]

[Illustration: _Fig. 19. Parting Tool._]

[Illustration: _Fig. 20. Knife Tool._]

[Illustration: _Fig. 21. Right-hand Side Tool._]

[Illustration: _Fig. 22. Internal Tool._]

[Illustration: _Fig. 23. Left-hand Side Tool._]

Coarse wheels are an abomination for tool work. Use the finest kinds
devised for the purpose. They will keep in condition longer, are not so
liable to wear unevenly, and will always finish off the edge better than
the coarse variety.

LATHE BITS.--All bits made for lathes are modifications of the foregoing
types (Figs. 18, 19, 20, 21, 22, 23).

As this chapter deals with the sharpening methods only, the reader is
referred to the next chapter, which deals with the manner of setting
and holding them to do the most effective work.

When it is understood that a cutting tool in a lathe is simply a form of
wedge which peels off a definite thickness of metal, the importance of
proper grinding and correct position in the lathe can be appreciated.

ROUGHING TOOLS.--The most useful is the roughing tool to take off the
first cut. As this type of tool is also important, with some
modifications, in finishing work, it is given the place of first
consideration here.

[Illustration: _Fig. 24. Tool for Wrought iron._ _Fig. 25. Tool for Cast
iron._]

Fig. 24 shows side and top views of a tool designed to rough off wrought
iron, or a tough quality of steel. You will notice, that what is called
the top rake (A) is very pronounced, and, as the point projects
considerably above the body of the tool itself, it should, in practice,
be set with its cutting point above the center.

THE CLEARANCE.--Now, in grinding, the important point is the clearance
line (B). As shown in this figure, it has an angle of 10 degrees, so
that in placing the tool in the holder it is obvious it cannot be placed
very high above the center, particularly when used on small work. The
top rake is ground at an angle of 60 degrees from the vertical. The arc
of the curved end depends on the kind of lathe and the size of the work.

The tool (Fig. 25), with a straight cutting edge, is the proper one to
rough off cast iron. Note that the top rake (C) is 70 degrees, and the
clearance 15 degrees.

THE CUTTING ANGLE.--Wrought iron, or mild steel, will form a ribbon when
the tool wedges its way into the material. Cast iron, on the other hand,
owing to its brittleness, will break off into small particles, hence the
wedge surface can be put at a more obtuse angle to the work.

In grinding side-cutters the clearance should be at a less angle than 10
degrees, rather than more, and the top rake should also be less;
otherwise the tendency will be to draw the tool into the work and swing
the tool post around.

DRILLS.--Holders for grinding twist drills are now furnished at very low
prices, and instructions are usually sent with the machines, but a few
words may not be amiss for the benefit of those who have not the means
to purchase such a machine.

Hand grinding is a difficult thing, for the reason that through
carelessness, or inability, both sides of the drill are not ground at
the same angle and pitch. As a result the cutting edge of one side will
do more work than the other. If the heel angles differ, one side will
draw into the work, and the other resist.

[Illustration: _Fig. 26. End view._ _Fig. 27. Side view._]

WRONG GRINDING.--When such is the case the hole becomes untrue. The
sides of the bit will grind into the walls, or the bit will have a
tendency to run to one side, and particularly if boring through metal
which is uneven in its texture or grain.

Figs. 26 and 27 show end and side views of a bit properly ground. If a
bit has been broken off, first grind it off square at the end, and then
grind down the angles, so that A is about 15 degrees, and be sure that
the heel has sufficient clearance--that is, ground down deeper than the
cutting point.

CHISELS.--A machine shop should always have a plentiful supply of cold
chisels, and a particular kind for each work, to be used for that
purpose only. This may seem trivial to the boy, but it is really a most
important matter.

Notice the careless and incompetent workman. If chipping or cutting is
required, he will grasp the first chisel at hand. It may have a curved
end, or be a key-way chisel, or entirely unsuited as to size for the
cutting required.

The result is an injured tool, and unsatisfactory results. The rule
holds good in this respect as with every other tool in the kit. _Use a
tool for the purpose it was made for_, and for no other. Acquire that
habit.

COLD CHISELS.--A cold chisel should never be ground to a long, tapering
point, like a wood chisel. The proper taper for a wood chisel is 15
degrees, whereas a cold chisel should be 45 degrees. A drifting chisel
may have a longer taper than one used for chipping.

It is a good habit, particularly as there are so few tools which require
grinding, to commence the day's work by grinding the chisels, and
arranging them for business.

SYSTEM IN WORK.--Then see to it that the drills are in good shape; and
while you are about it, look over the lathe tools. You will find that it
is better to do this work at one time, than to go to the emery wheel a
dozen times a day while you are engaged on the job.

Adopt a system in your work. Don't take things just as they come along,
but form your plans in an orderly way, and you will always know how to
take up and finish the work in the most profitable and satisfactory way.

WRONG USE OF TOOLS.--Never use the vise as an anvil. Ordinary and proper
use of this tool will insure it for a lifetime, aside from its natural
wear. It may be said with safety that a vise will never break if used
for the purpose for which it was intended. One blow of a hammer may ruin
it.

Furthermore, never use an auxiliary lever to screw up the jaws. If the
lever which comes with it is not large enough to set the jaws, you may
be sure that the vise is not large enough for your work.




CHAPTER III

SETTING AND HOLDING TOOLS


Some simple directions in the holding and setting of tools may be of
service to the novice. Practice has shown the most effective way of
treating different materials, so that the tools will do the most
efficient work.

A tool ground in a certain way and set at a particular angle might do
the work admirably on a piece of steel, but would not possibly work on
aluminum or brass.

LATHE SPEED.--If the lathe should run at the same speed on a piece of
cast iron as with a brass casting, the result would not be very
satisfactory, either with the tool or on the work itself.

Some compositions of metal require a high speed, and some a hooked tool.
These are things which each must determine as the articles come to the
shop; but there are certain well-defined rules with respect to the
ordinary metals that should be observed.

THE HACK SAW.--Our first observation should be directed to the hand
tools. The hack saw is one of the most difficult tools for the machinist
to handle, for the following reasons:

First, of the desire to force the blade through the work. The blade is a
frail instrument, and when too great a pressure is exerted it bends, and
as a result a breakage follows. To enable it to do the work properly, it
must be made of the hardest steel. It is, in consequence, easily
fractured.

[Illustration: _Fig. 28.--Hack Saw Frame._]

[Illustration: _Fig. 29.--Hack Saw Blade._]

Second. The novice will make short hacking cuts. This causes the teeth
to stick, the saw bends, and a new blade is required. Take a long
sweeping cut, using the entire length of the blade. Do not oscillate the
blade as you push it through the work, but keep the tooth line
horizontal from one end of the stroke to the other. The moment it begins
to waver, the teeth will catch on the metal on the side nearest to you,
and it will snap.

Third. The handle is held too loosely. The handle must be firmly held
with the right hand, and the other held by the fingers lightly, but in
such a position that a steady downward pressure can be maintained. If
loosely held, the saw is bound to sag from side to side during the
stroke, and a short stroke accentuates the lateral movement. A long
stroke avoids this.

The hack saw is one of the tools which should be used with the utmost
deliberation, combined with a rigid grasp of the handle.

FILES.--For remarks on this tool see Chapter IV, which treats of the
subject specially.

GRINDSTONES, EMERY AND GRINDING WHEELS.--A good workman is always
reflected by his grinding apparatus. This is true whether it has
reference to a grindstone, emery, corundum wheel, or a plain oil stone.
Nothing is more destructive of good tools than a grooved, uneven, or
wabbly stone. It is only little less than a crime for a workman to hold
a tool on a revolving stone at one spot.

CARELESSNESS IN HOLDING TOOLS.--The boy must learn that such a habit
actually prevents the proper grinding, not only of the tool he has on
the stone, but also of the one which follows. While it is true that all
artificially made grinders will wear unevenly, even when used with the
utmost care, due to uneven texture of the materials in the stone,
still, the careless use of the tool, while in the act of grinding, only
aggravates the trouble.

Another fault of the careless workman is, to press the bit against the
stone too hard. This cuts the stone more than it wears off the tool, and
it is entirely unnecessary. Furthermore, it heats up the tool, which
should be avoided.

CALIPERS.--A true workman, who endeavors to turn out accurate work, and
preserve his tools, will never test the work with his calipers while the
piece is turning in the lathe. A revolving cast iron disk will cut ruby,
the hardest substance next to the diamond, so it is not the hardness of
the material which resists wear, but the conditions under which it is
used.

CARE IN USE OF CALIPERS.--The calipers may be of the most hardened
steel, and the work turned up of the softest brass, the latter, when
revolving, will grind off the point of the tool, for the reason that the
revolving piece constantly presents a new surface to the point of the
calipers, and when tests are frequently made, it does not take long to
change the caliper span so that it must be reset.

As stated elsewhere, the whole energy of the lathe is concentrated on
the bit or cutting tool, hence, in order to get the most effective work
out of it requires care; first, in grinding; and, second, in setting.

MACHINE BITS.--It does not always matter so much whether you use a
square, pointed, or a round-nosed bit, provided it is properly ground
and set in the tool holder. As a rule, the more brittle the metal the
less the top rake or angle should be.

In the chapter relating to the grinding of tools, references were made
as to the most serviceable bits for the various metals. We are concerned
here with the setting or holding of these articles.

[Illustration: _Fig. 30. Plain Hook Tool_ _Fig. 31. Plain Straight
Tool._]

The two illustrations here given show a pair of plain bits, in which
Fig. 30 represents a hook-shaped formation, and Fig. 31 a straight
grind, without any top rake. The hooked bit would do for aluminum, or
steel, but for cast iron the form shown in Fig. 31 would be most
serviceable.

Then the side bits, such as the round-nosed, Fig. 32 and the square end,
Fig. 33, may be ground hooked, or with a top rake, or left flat.

The too common mistake is to grind the lower or clearance side at too
great an angle. Fig. 34 shows the correct angle, and the dotted line A
illustrates the common tendency to grind the clearance.

THE PROPER ANGLE FOR LATHE TOOLS.--Now there is a reason why the angle
of from 10 to 15 should be maintained in the clearance. The point of the
tool must have suitable support for the work it is required to do, so it
will not chatter or yield in the slightest degree. A bit ground along
the dotted line has a cutting edge which will spring down, and
consequently break or produce a rough surface.

[Illustration: _Fig. 32. Fig. 33. Fig. 34. Proper Angles for Tools_]

Then, again, the angle of the clearance acts as a guide, or rather, a
guard, to prevent the tool from going in too far, as will now be
explained.

SETTING THE BIT.--In order to understand the correct setting, examine
the work A, in Fig. 35.

A is a cylinder being turned up in the lathe, and B the cutting tool,
which approaches it on a horizontal line, C, extending out from the
center of the cylinder A. This setting is theoretically correct, and in
practice has been found most advantageous.

In this case let us assume that the clearance angle D is 15 degrees, as
well as in the following figures.

[Illustration: _Fig. 35. Set of the Bit_]

Suppose we have a piece of tough steel, and the tool holder is raised so
that the point of the tool is at the 15 degree line E, as shown in Fig.
36, in which case the clearance line D is at right angles to the line E.
The line E is 15 degrees above the center line C.

THE SETTING ANGLE.--Now, it is obvious that if the tool should be raised
higher than the line E it would run out of work, because the clearance
surface of the tool would ride up over the surface cut by the edge of
the tool.

If, on the other hand, the tool should be placed lower, toward the line
C, the tendency would be to draw in the tool toward the center of the
work A.

In Fig. 37 the tool has its point elevated, in which case it must be
lowered so the point will touch the work nearer the center line C.

The foregoing arrangement of the tools will be found to be effective
where the material is soft and not too tough as with aluminum.

BAD PRACTICE.--Figs. 38 and 39 show illustrations of bad practice which
should never be resorted to. Fig. 38 shows the tool, held in a
horizontal position, but with its point below the center line C. With
any rough metal the tool could not possibly work, except to act as a
scraper, and if it should be used in that position on cast iron, the
tool itself would soon be useless.

[Illustration: _Fig. 36. Correct Angle_ _Fig. 37. Wrong Angle_]

Fig. 39 is still worse, and is of no value for any purpose except in
polishing brass, where it would be serviceable. It would make a sorry
looking job with aluminum. Brass requires a tool with very little top
rake, and the point should be set near the center line C.

LATHE SPEED.--It is often a question at what speeds to run the lathe for
different work. If you know the speeds of your lathe at low and high
gear, you must also consider the diameter of the work at the cutting
point.

The rule is to have the bit cut from 15 to 20 feet per minute for
wrought iron; from 11 to 18 feet for steel; from 25 to 50 for brass; and
from 40 to 50 for aluminum.

[Illustration: _Fig. 38. Too Low_ _Fig. 39. Improper Set_]

As a result, therefore, if, at low speed, a piece 10 inches in diameter,
runs at the proper speed to cut at that distance from the center, it is
obvious that a piece 5 inches in diameter should ran twice as fast. This
is a matter which time and practice will enable you to judge with a fair
degree of accuracy.

Observe this as a maxim: "Slow speed, and quick feed."

BORING TOOLS ON LATHE.--The lathe is a most useful tool for boring
purposes, better for some work than the drilling machine itself. The
work which can be done better on a lathe than on a drilling machine, may
be classified as follows:

1. When straight and true holes are required.

2. In long work, where the lathe is used to turn up the article, and
where the drilling can be done at the same time.

3. Anything that can be chucked in a lathe.

4. Where the work is long and cannot be fixed in a drilling machine. The
long bed of the lathe gives room for holding such work.

[Illustration: _Fig. 40. Internal Set_ _Fig. 41. Set for Brass_]

THE RAKE OF THE DRILL.--A boring tool requires some knowledge in
setting. It should have a greater top rake than for the outside work,
and the cutting edge should also be keener, as a rule.

[Illustration: _Fig. 42.--Surface Gage._]

In this class of work the material bored must be understood, as well as
in doing outside work.

The hooked tool, Fig. 40, is shown to be considerably above the center
line, and at that point it will do the most effective cutting on steel.
If, on the other hand, brass is operated on there should be no top
rake, as illustrated in Fig. 41, thus assuring a smooth job.

LAPS.--This is a tool which is very useful, particularly for grinding
and truing up the cylinders of internal combustion engines, as well as
for all kinds of bores of refractory material which cannot be handled
with the cutting tool of the lathe.

It is made up of a mandrel or rod of copper, with lead cast about it,
and then turned up true, so that it is but the merest trifle larger than
the hole it is to true up.

USING THE LAP.--The roller thus made is turned rapidly in a lathe, and
the cylinder to be trued is brought up to it and the roller supplied
freely with emery powder and oil. As rapidly as possible the cylinder is
worked over on the roller, without forcing it, and also turned, so as to
prevent even the weight from grinding it unduly on one side.

More or less of the emery will embed itself in the lead, and thus act as
an abrasive. The process is called "lapping."

SURFACE GAGES.--Frequently, in laying out, it is necessary to scribe
lines at a given distance from some part of the work; or, the conditions
are such that a rule, a caliper, or dividers will not permit accurate
measurement to be made.

For such purposes, what is called a surface gage was devised. This is
merely a heavy base, provided with a pivoted upright on which is
mounted a scribe that is held by a clamp so it may be turned to any
angle.

[Illustration: _Fig. 43.--Showing uses of the Surface Gage._]

SURFACE GAGE.--The clamp holding the scriber is vertically movable on
the pivoted upright. By resting the base of the surface gage on the line
to be measured from, and swinging one point of the scriber to the place
where the work is to be done, accuracy is assured. One end of the
scriber is bent, so it can be adapted to enter recesses, or such places
as could not be reached by the straight end.




CHAPTER IV

ON THE USE OF THE FILE


The most necessary tool in a machine shop is a file. It is one of the
neglected tools, because the ordinary boy, or workman, sees nothing in
it but a strip or a bar with a lot of cross grooves and edges, and he
concludes that the only thing necessary is to rub it across a piece of
metal until he has worn it down sufficiently for the purpose.

THE FIRST TEST.--The fact is, the file is so familiar a tool, that it
breeds contempt, like many other things closely associated in life.

Give the boy an irregular block of metal, and tell him to file it up
square, and he will begin to realize that there is something in the
handling of a file that never before occurred to him.

He will find three things to astonish him:

First: That of dimensions.

Second: The difficulty of getting it square.

Third: The character of the surface when he has finished it.

FILING AN IRREGULAR BLOCK.--To file a block of an irregular character so
that the dimensions are accurate, is a good test for an accomplished
workman. The job is made doubly difficult if he is required to file it
square at the same time. It will be found, invariably, that the sides
will not be parallel, and by the time it is fully trued up the piece
will be too small. See Figs. 44 and 45.

Then, unless the utmost care is taken, the flat sides _will not_ be
flat, but rounded.

FILING A BAR STRAIGHT.--The next test is to get the boy to file a bar
straight. He has no shaper or planer for the purpose, so that it must be
done by hand. He will find himself lacking in two things: The edge of
the bar will not be straight; nor will it be square with the side of the
bar.

[Illustration: _Fig. 44. Rounded Surface_ _Fig. 45. A Winding Face_]

FILING BAR WITH PARALLEL SIDES.--Follow up this test by requiring him to
file up a bar, first, with two exactly parallel sides, and absolutely
straight, so it will pass smoothly between the legs of a pair of
calipers, and then file the two other sides in like manner.

SURFACING OFF DISKS.--When the foregoing are completed there is still
another requirement which, though it appears simple, is the supreme
test. Set him to work at surfacing off a pair of disks or plates, say
one and a half inches in diameter, so that when they are finished they
will fit against each other perfectly flat.

A pair of such disks, if absolutely true, will hold together by the
force of cohesion, even in a dry state, or they will, as it were, float
against each other.

TRUE SURFACING.--Prior to about 1850 the necessity of true surfacing was
not so important or as well known as at the present time. About that
period Sir J. Whitworth, an eminent English engineer and mechanic,
called the attention of machinists to the great advantage arising from
true surfaces and edges for all types of machinery, and he laid the
foundation of the knowledge in accurating surfacing.

PRECISION TOOLS.--Due to his energy many precision tools were made, all
tending to this end, and as a result machines became better and more
efficient in every way.

It had this great advantage: It taught the workman of his day how to use
the file and scraper, because both must be used conjunctively to make an
absolutely flat plate.

Contrary to general beliefs, shapers and planers do not make absolutely
accurate surfaces. The test of this is to put together two plates so
planed off. There is just enough unevenness to permit air to get between
the plates. If they were perfectly true they would exclude all air, and
it would be a difficult matter to draw them apart.

TEST OF THE MECHANIC.--To make them perfectly flat, one plate has chalk
rubbed over it, and the two plates are then rubbed together. This will
quickly show where the high spots are, and the file and scraper are then
used to cut away the metal.

[Illustration: _Fig. 46. Fig. 47. Hexagon Nut_]

In England the test of the mechanic used to be determined by his ability
to file a piece of metal flat. It was regarded as the highest art. This
is not the most desirable test at the present time, and it is recognized
that a much severer test is to file a narrow piece exactly flat, and so
that it will not have a trace of roundness, and be square from end to
end.

TEST SUGGESTIONS.--In a shop which does not have the advantage of a
planer or shaper, there are so many articles which must be filed up,
that it is interesting to know something of how the various articles are
made with a file.

To file a hexagon, or six-sided nut will be a good test with a file. To
do this a little study in geometrical lines will save a vast amount of
time. In beginning the work, measure the radius with a divider, and then
step off and make six marks equidistant from each other on the round
surface.

[Illustration: _Fig. 48. Cutting Key-way_]

USE OF THE DIVIDERS.--The distance between each of these points is equal
to the radius, or half the diameter, of the round bar. See Fig. 46,
which shows this. The marks should be scribed across the surface, as
shown in Fig. 47, where the lines show the ends of the facets of the
outside of the nut.

Do not let the file obliterate the lines at the rough cutting, but
leave enough material so you can make a good finish at the line.

CUTTING A KEY-WAY.--Another job you may have frequent occasion to
perform, is to cut a way for a key in a shaft and in a wheel hub.
Naturally, this will be first roughed out with a cold chisel narrower
than the key is to be, and also slightly shallower than the dimensions
of the key.

A flat file should be used for the purpose, first a heavy rough one, for
the first cutting. The better way is to have the key so it can be
frequently tried while the filing process is going on, so that to fit
the key in this way is a comparatively easy task.

KEY-WAY DIFFICULTIES.--But the trouble commences when the groove is
filed for the depth. Invariably, the mistake will be made of filing the
width first, so the key will fit in. As a result, in deepening the
groove the file will contact with the walls, and you have a key-way too
wide for the key.

To avoid this, file the depth, or nearly so, and then with a fine file
cut in the corners in the direction indicated by the dart, Fig. 48.

A proper key is square in cross section. In such a case the depth of the
key-way, at each side wall, is just half the width of the key-way.

An excellent key-seat rule can be made by filing out two right-angled
pieces, as shown in Fig. 49, which can be attached to the ordinary
six-inch metal rule, and this will enable you to scribe the line
accurately for the key-way on the shaft.

[Illustration: _Fig. 49. Key-seat Rule_]

[Illustration: _Fig. 50. Fig. 51. Filing Metal Round_]

FILING METAL ROUND.--It is sometimes necessary to file a piece of metal
round. This is a hard job, particularly where it is impossible to scribe
the end of the piece. Suppose it is necessary to file up a bearing
surface, or surfaces, intermediate the ends of a square bar.

You have in that case four sides to start from, the opposite sides
being parallel with each other, so that you will have two dimensions,
and four equal sides, as shown in Fig. 50.

The first step will be to file off accurately the four corners 1, 2, 3,
4, so as to form eight equal sides or faces, as shown in Fig. 51. If you
will now proceed to file down carefully the eight corners, so as to make
sixteen sides, as in Fig. 52, the fourth set of corners filed down will
make the filed part look like the illustration Fig. 53 with thirty-two
faces.

[Illustration: _Fig. 52. Fig. 53. Making a Bar Round_]

This may be further filed down into sixty-four faces, and a few cuts of
the finishing file will take off the little ridges which still remain.
By using emery cloth, and wrapping it around the bearing portion, and
changing it continually, while drawing it back and forth, will enable
you to make a bearing which, by care, will caliper up in good shape.

KINDS OF FILES.--Each file has five distinct properties; namely: the
length, the contour, the form in cross section, the kind of teeth, and
the fineness of the teeth.

There are nine well-defined shapes for files. These may be enumerated as
follows:

[Illustration: _Fig. 54. Cross Sections of Files._]

No. 1. The cotter file. The small kind is called a verge or pivot file.

No. 2. Square file, which may be tapering from end to end, or have
parallel sides throughout.

No. 3. Watch pinion file. This may have its sides parallel or tapering,
to make a knife-shaped file.

No. 4. Clock-pinion; which may be used for either nicking, piecing, or
squaring-off purposes.

No. 5. Round, with parallel sides for gulleting purposes, or rat-tail
when it tapers.

No. 6. Triangular, or three equally-sided body for saw filing.

No. 7. Equalizing file. This is parallel when used for making
clock-pinions or endless screws; or for slitting, entering, warding, or
making barrel holes, when the body of the file tapers.

No. 8. Cross, or double-round, half-file.

No. 9. Slitting file; which has parallel sides only. A cant file.

CHARACTER OF THE FILE TOOTH.--Files are distinguished principally by the
character of the oblique, or cross grooves and ridges which do the
cutting and abrading when the file is drawn across the surface.

This is really more important than the shape, because the files, by
their cuttings, are adapted for the various materials which they are to
be used upon.

The files are classified as _Double Cut_, of which there are the
_rough_, _middle_, _bastard_, _second cut_, _smooth_, and _dead smooth_.

The _Float Cut_, which is either _rough_, _bastard_ or _smooth_; and

The _Rasp Cut_, either _rough_, _bastard_ or _smooth_.

Several types are illustrated in Fig. 55, which show the characteristics
of the various cuts.

The rasps are used principally for soft material, such as wood or for
hoofs, in horse shoeing, hence they need not be considered in connection
with machine-shop work.

[Illustration: _Fig. 55. Files._]

HOLDING THE FILE.--The common mistake on the part of the beginner is to
drag the file across the work at an angle. The body of the file should
move across straight and not obliquely.

Note this movement in Fig. 56 where the dash shows the correct movement
of the file with relation to the work. Also observe that the file
cutting ridges are not straight across the file, but at an angle to the
direction of the dart.

[Illustration: _Fig. 56. Correct File Movement_]

INJURING FILES.--Now the frequent practice is to use the file as shown
in Fig. 57, in which case it is moved across obliquely. The result is
that the angle of the file cut is so disposed that the teeth of the file
do not properly aid in the cutting, but in a measure retard the
operation.

File teeth are disposed at an angle for the purpose of giving them a
shearing cut, which is the case when the file moves across the work on a
line with its body.

To use a file as shown in Fig. 57 injures the file without giving it an
opportunity to cut as fast as it would when properly used.

[Illustration: _Fig. 57. Incorrect File Movement_]

DRAWING BACK THE FILE.--In drawing back a file it is always better to
allow it to drag over the work than to raise it up. It is frequently the
case that some of the material will lodge in the teeth, and the back
lash will serve to clear out the grooves.

This is particularly true in filing copper, aluminum, lead, and like
metals, but it is well to observe this in all cases.




CHAPTER V

HOW TO COMMENCE WORK


The question is often asked: Where and how shall the novice commence
work?

When the shop is equipped, or partially so, sufficient, at least, to
turn out simple jobs, the boy will find certain tools which are
strangers to him. He must become acquainted with them and not only learn
their uses, but how to use them to the best advantage.

FAMILIARITY WITH TOOLS.--Familiarity with the appearance of tools, and
seeing them in the hands of others will not be of any value. Nothing but
the immediate contact with the tool will teach how to use it.

FILE PRACTICE.--The file is a good tool to pick up first. Select a piece
of metal, six or eight inches long, and follow the instructions laid
down in the chapter relating to the use of the file.

Practice with several kinds and with different varieties of material
will soon give an inkling of the best kind to use with the metal you
have. Use the straight edge and the square while the filing process is
going on, and apply them frequently, to show you what speed you are
making and how nearly true you are surfacing up the piece.

USING THE DIVIDERS.--Then try your hand using the dividers, in
connection with a centering punch. As an example, take two pieces of
metal, each about a foot long, and set the dividers to make a short
span, say an inch or so, and step off the length of one piece of metal,
and punch the last mark. Then do likewise with the other piece of metal,
and see how nearly alike the two measurements are by comparing them.

You will find a variation in the lengths of the two measurements at the
first trials, and very likely will not be able to make the two pieces
register accurately after many trials, even when using the utmost care.

Sooner or later you will learn that you have not stepped paths along the
two bars which were exactly straight, and this will account for the
variations. In order to be accurate a line should be drawn along each
piece of metal, and the dividers should step off the marks on that line.

FINDING CENTERS.--By way of further experiment, it might be well to find
the exact center of the ends of a square bar, putting in the punch marks
and then mounting it in the lathe centers to see how accurately this has
been done.

If either end is out of true the punch marks can be corrected by
inclining the punch, so that when it is struck it will move over the
point in the direction of its true center. This may be followed up by
centering the end of a round bar so as to make it true. This will be
found to be a more difficult job, unless you have a center head, a tool
made for that purpose.

It is good practice, however, to make trials of all this work, as it
will enable you to judge of measurements. It can be done with the
dividers by using care in scribing the centers.

HACK-SAW PRACTICE.--Practice with the hack-saw should be indulged in
frequently. Learn to make a straight cut through a bar. Try to do this
without using a square to guide you. One of the tests of a good mechanic
is ability to judge a straight cut.

The following plan is suggested as a test for the eye. Use a bar of iron
or steel one inch square, and make a cut an eighth of an inch deep
across it; then turn it around a quarter, so as to expose the nest face,
and continue the cut along the side, the same depth, and follow this up
with the remaining two sides, and see how near the end of the first cut
and the finish cut come together. The test will surprise you.

CUTTING METALS TRUE.--When you saw off the end of such a bar for trial
purposes, use a square, after the cut is made, and note how much it is
out of true in both directions. It is a curious fact that most mechanics
are disposed to saw or cut crooked in one direction, either to the right
or to the left. In tests made it is found that this defect is persisted
in.

It is practice only which will remedy this, and it would be well for the
boy to learn this for himself as early in his career as possible, and
correct the tendency to veer in either direction.

The test of sawing around a round bar is also commended. After a few
trials you will be surprised to see how your judgment will improve in
practice.

LATHE WORK.--Learn the uses of the chuck. As you have, probably,
economized as much as possible, a universal chuck is not available,
hence the first experience will be with an independent chuck, where the
three dogs move independently of each other. This will give you some
work to learn how you can get the job true.

Now, before attempting to cut the material, thoroughly learn all the
parts of the feed mechanism, and how to reverse, as well as to cross
feed. Learn the operation of the operative parts so that your hand will
instinctively find them, while the eye is on the work.

FIRST STEPS.--See to it that your tools are sharp, and at the first
trials make light cuts. Practice the feeds by manually moving the tool
holder, for surface cutting as well as for cross cutting.

SETTING THE TOOL.--Set the cutting tool at various angles, and try the
different tools, noting the peculiarities of each, at the different
speeds. Do not, by any means, use refractory metals for your first
attempt. Mild steel is a good test, and a light gray iron is admirable
for practice lessons.

METALS USED.--Brass is good for testing purposes, but the difficulty is
that the tendency of the boy, at first, is to try to do the work too
rapidly, and brass encourages this tendency. Feed slowly and regularly
until you can make an even finish.

Then chuck and re-chuck to familiarize yourself with every operative
part of the lathe, and never try to force the cutting tool. If it has a
tendency to run into the work, set it higher. If, on the other hand, you
find, in feeding, that it is hard to move the tool post along, the tool
is too high, and should be lowered.

THE FOUR IMPORTANT THINGS.--Constant practice of this kind will soon
enable you to feel instinctively when the tool is doing good work. While
you are thus experimenting do not forget the speed. This will need your
attention.

Remember, you have several things to think about in commencing to run
the lathe, all of which will take care of themselves when it becomes
familiar to you. These may be enumerated as follows:

First: The kind of tool best to use.

Second: Its proper set, to do the best work.

Third: The speed of the work in the lathe.

Fourth: The feed, or the thickness of the cut into the material.

TURNING UP A CYLINDER.--The first and most important work is to turn up
a small cylinder to a calipered dimension. When it is roughed down ready
for the finish cut, set the tool so it will take off a sufficient amount
to prevent the caliper from spanning it, and this will enable you to
finish it off with emery paper, or allow another small cut to be taken.

TURNING GROOVES.--Then follow this up by turning in a variety of annular
grooves of different depths and widths; and also V-shaped grooves, the
latter to be performed by using both the longitudinal and transverse
feeds. This will give you excellent practice in using both hands
simultaneously.

The next step would be to turn out a bore and fit a mandrel into it.
This will give you the opportunity to use the caliper to good advantage,
and will test your capacity to use them for inside as well as for
outside work.

DISCS.--A job that will also afford good exercise is to turn up a disc
with a groove in its face, and then chuck and turn another disk with an
annular rib on its face to fit into the groove. This requires delicacy
of measurement with the inside as well as the outside calipers.

The groove should be cut first, and the measurement taken from that, as
it is less difficult to handle and set the tool for the rib than for the
groove.

LATHE SPEEDS.--Do not make the too common mistake of running the mandrel
at high speeds in your initial tests. It is far better to use a slow
speed, and take a heavy cut. This is good advice at all times, but it is
particularly important with beginners.




CHAPTER VI

ILLUSTRATING SOME OF THE FUNDAMENTAL DEVICES


There are numerous little devices and shop expedients which are
desirable, and for which the boy will find uses as he progresses.

We devote this chapter to hints of this kind, all of which are capable
of being turned out or utilized at various stages.

LACING BELTS.--To properly lace a belt is quite an art, as many who have
tried it know. If a belt runs off the pulley it is attributable to one
of three causes: either the pulleys are out of line or the shafts are
not parallel or the belt is laced so it makes the belt longer at one
margin than the other.

In Fig. 58 the lacing should commence at the center hole (A) of one belt
end and lace outwardly, terminating at the hole (B) in the center of the
other belt end, as shown in Fig. 58.

In Fig. 59 the lacing commences at A, and terminates at the hole (B) at
the edge. This will be ample for all but the widest belts.

Fig. 60 is adapted for a narrow belt. The lacing commences at one margin
hole (A), and terminates at the other margin hole (Z).

Fig. 61 shows the outside of the belt.

Fig. 62. GEARS.--This is something every boy ought to know about. Fig.
62 shows a pair of intermeshing bevel gears. This is the correct term
for a pair when both are of the same diameter.

[Illustration: _Inside Fig. 58. Belt Lacing_
 _Outside Fig. 58. Belt Lacing_
 _Fig. 59. Belt Lacing_
 _Fig. 60. Belt Lacing_
 _Fig. 61. Belt Lacing_]

MITER GEARS.--In Fig. 63 we have a pair of miter gears, one being larger
than the other. Remember this distinction.

Fig. 64. CROWN WHEEL.--This is a simple manner of transmitting motion
from one shaft to another, when the shafts are at right angles, or
nearly so, without using bevel or miter gears.

Fig. 65. GROOVED FRICTION GEARING.--Two grooved pulleys, which fit each
other accurately, will transmit power without losing too much by
friction. The deeper the grooves the greater is the loss by friction.

Fig. 66. A VALVE WHICH CLOSES BY THE WATER PRESSURE.--The bibb has
therein a movable valve on a horizontal stem, the valve being on the
inside of the seat. The stem of the handle has at its lower end a crank
bend, which engages with the outer end of the valve stem. When the
handle is turned in either direction the valve is unseated. On releasing
the handle the pressure of the water against the valve seats it.

Fig. 67. CONE PULLEYS.--Two cone pulleys of equal size and taper provide
a means whereby a change in speed can be transmitted from one shaft to
another by merely moving the belt to and fro. The slightest change is
available by this means.

Fig. 68. UNIVERSAL JOINT.--A wheel, with four projecting pins, is placed
between the U-shaped yokes on the ends of the approaching shafts. The
pins serve as the pivots for the angles formed by the two shafts.

Fig. 69. TRAMMEL FOR MAKING AN ELLIPSE.--This is a tool easily made,
which will be of great service in the shop. In a disc (A), preferably
made of brass, are two channels (B) at right angles to each other. The
grooves are undercut, so that the blocks (C) will fit and slide in the
grooves and be held therein by the dove-tailed formation. Each block is
longer than the width of the groove, and has an outwardly projecting pin
which passes through a bar (D). One pin (E) is movable along in a slot,
but is adjustable at any point so that the shape of the ellipse may be
varied. The end of the bar has a series of holes (G) for a pencil, so
that the size of the ellipse may also be changed.

[Illustration: _Fig. 62. Bevel Gears_
 _Fig. 63. Miter Gears_
 _Fig. 64. Crown Wheel_
 _Fig. 65. Grooved Friction Gears_
 _Fig. 66. Valve_
 _Fig. 67. Cone Pulleys_
 _Fig. 68. Universal Joint_]

Fig. 70. ESCAPEMENTS.--Various forms of escapements may be made, but the
object of all is the same. The device is designed to permit a wheel to
move intermittingly or in a step by step movement, by the swinging
motion of a pendulum. Another thing is accomplished by it. The teeth of
the escapement are cut at such an angle that, as one of the teeth of the
escapement is released from one tooth of the escapement wheel, the
spring, or the weight of the clock, will cause one of the teeth of the
escapement wheel to engage the other tooth of the escapement, and give
the pendulum an impulse in the other direction. In the figure, A is the
escapement, B the escapement wheels and _a_, _b_, the pallets, which
are cut at suitable angles to actuate the pendulum.

Fig. 71. SIMPLE DEVICE TO PREVENT A WHEEL OR SHAFT FROM TURNING
BACK.--This is a substitute for a pawl and ratchet wheel. A is a drum or
a hollow wheel and B a pulley on a shaft, and this pulley turns loosely
with the drum (A). Four tangential slots (C) are cut into the perimeter
of the pulley (B), and in each is a hardened steel roller (D). It
matters not in what position the wheel (B) may be, at least two of the
rollers will always be in contact with the inside of the drum (A), and
thus cause the pulley and drum to turn together. On reversing the
direction of the pulley the rollers are immediately freed from binding
contact.

Fig. 72. RACKS AND PINIONS.--The object of this form of mechanism is to
provide a reciprocating, or back-and-forth motion, from a shaft which
turns continually in one direction. A is the rack and B a mutilated
gear. When the gear turns it moves the rack in one direction, because
the teeth of the gear engage the lower rack teeth, and when the rack has
moved to the end its teeth engage the teeth of the upper rack, thus
reversing the movement of the rack.

Fig. 73. MUTILATED GEARS.--These are made in so many forms, and adapted
for such a variety of purposes, that we merely give a few samples to
show what is meant by the term.

[Illustration: _Fig. 69. Trammel_
 _Fig. 70. Escapement_
 _Fig. 71. Device for Holding Wheel_
 _Fig. 72. Rack and Pinion_
 _Fig. 73. Mutilated Gears_
 _Fig. 74. Shaft Coupling_]

Fig. 74. SIMPLE SHAFT COUPLING.--Prepare two similarly formed discs (A,
B), which are provided with hubs so they may be keyed to the ends of the
respective shafts. One disc has four or more projecting pins (C), and
the other disc suitable holes (D) to receive the pins.

Fig. 75. CLUTCHES.--This is a piece of mechanism which is required in so
many kinds of machinery, that we show several of the most approved
types.

Fig. 76. BALL AND SOCKET JOINTS.--The most practical form of ball and
socket joints is simply a head in which is a bowl-shaped cavity the
depth of one-half of the ball. A plate with a central opening small
enough to hold in the ball, and still large enough at the neck to
permit the arm carrying the ball to swing a limited distance, is secured
by threads, or by bolts, to the head. The first figure shows this.

Fig. 77 illustrates a simple manner of tightening the ball so as to hold
the standard in any desired position.

Fig. 78. TRIPPING DEVICES.--These are usually in the form of hooks, so
arranged that a slight pull on the tripping lever will cause the
suspended articles to drop.

Fig. 79. ANCHOR BOLT.--These are used in brick or cement walls. The bolt
itself screws into a sleeve which is split, and draws a wedge nut up to
the split end of the sleeve. As a result the split sleeve opens or
spreads out and binds against the wall sufficiently to prevent the bolt
from being withdrawn.

Fig. 80. LAZY TONGS.--One of the simplest and most effective instruments
for carrying ice, boxes or heavy objects, which are bulky or
inconvenient to carry. It grasps the article firmly, and the heavier the
weight the tighter is its grasp.

Fig. 81. DISC SHEARS.--This is a useful tool either for cutting tin or
paper, pasteboard and the like. It will cut by the act of drawing the
material through it, but if power is applied to one or to both of the
shafts the work is much facilitated, particularly in thick or hard
material.

[Illustration:
 _Fig. 75. Clutches_
 _Fig. 76. Ball and Socket Joints_
 _Fig. 77. Fastening Ball_
 _Fig. 78. Tripping Devices_
 _Fig. 79. Anchor Bolt_
 _Fig. 80. Lazy Tongs._
 _Fig. 81. Disc Shears._]

Fig. 82. WABBLE SAW.--This is a most simple and useful tool, as it will
readily and quickly saw out a groove so that it is undercut. The saw is
put on the mandrel at an angle, as will be seen, and should be run at a
high rate of speed.

Fig. 83. CRANK MOTION BY A SLOTTED YOKE.--This produces a straight
back-and-forth movement from the circular motion of a wheel or crank. It
entirely dispenses with a pitman rod, and it enables the machine, or the
part of the machine operated, to be placed close to the crank.

Fig. 84. CONTINUOUS FEED BY THE MOTION OF A LEVER.--The simple lever
with a pawl on each side of the fulcrum is the most effective means to
make a continuous feed by the simple movement of a lever. The form shown
is capable of many modifications, and it can be easily adapted for any
particular work desired.

[Illustration: _Fig. 82. Wabble Saw_
 _Fig. 83. Continuous Crank Motion_
 _Fig. 84. Continuous Feed_
 _Fig. 85. Crank Motion_
 _Fig. 86. Ratchet Head_
 _Fig. 87. Bench Clamp_]

Fig. 85. CRANK MOTION.--By the structure shown, namely, a slotted lever
(A), a quick return can be made with the lever. B indicates the fulcrum.

Fig. 86. RATCHET HEAD.--This shows a well-known form for common ratchet.
It has the advantage that the radially movable plugs (A) are
tangentially disposed, and rest against walls (B) eccentrically
disposed, and are, therefore, in such a position that they easily slide
over the inclines.

Fig. 87. BENCH CLAMP.--A pair of dogs (A, B), with the ends bent toward
each other, and pivoted midway between the ends to the bench in such a
position that the board (C), to be held between them, on striking the
rear ends of the dogs, will force the forward ends together, and thus
clamp it firmly for planing or other purposes.

[Illustration:
 _Fig. 88. Helico-Volute Spring_
 _Fig. 89. Double Helico-Volute_
 _Fig. 90. Helical Spring_
 _Fig. 91. Single Volute Helix-Spring_
 _Fig. 92. Flat Spiral or Convolute_
 _Fig. 93. Eccentric Rod and Strap_
 _Fig. 94. Anti-Dead Center for Foot-Lathes_]

Fig. 88. HELICO-VOLUTE SPRING.--This is a form of spring for tension
purposes. The enlarged cross-section of the coil in its middle portion,
with the ends tapering down to the eyes, provides a means whereby the
pull is transferred from the smaller to the larger portions, without
producing a great breaking strain near the ends.

Fig. 89. DOUBLE HELICO-VOLUTE.--This form, so far as the outlines are
considered, is the opposite of Fig. 88. A compression spring of this
kind has a very wide range of movement.

Fig. 90. HELICAL SPRING.--This form of coil, uniform from end to end, is
usually made of metal which is square in cross-section, and used where
it is required for heavy purposes.

Fig. 91. SINGLE VOLUTE HELIX-SPRING.--This is also used for compression,
intended where tremendous weights or resistances are to be overcome, and
when the range of movement is small.

Fig. 92. FLAT SPIRAL, OR CONVOLUTE.--This is for small machines. It is
the familiar form used in watches owing to its delicate structure, and
it is admirably adapted to yield to the rocking motion of an arbor.

Fig. 93. ECCENTRIC ROD AND STRAP.--A simple and convenient form of
structure, intended to furnish a reciprocating motion where a crank is
not available. An illustration of its use is shown on certain types of
steam engine to operate the valves.

Fig. 94. ANTI-DEAD CENTER FOR FOOT-LATHES.--A flat, spiral spring (A),
with its coiled end attached to firm support (B), has its other end
pivotally attached to the crank-pin (C), the tension of the spring being
such that when the lathe stops the crack-pin will always be at one side
of the dead-center, thus enabling the operator to start the machine by
merely pressing the foot downwardly on the treadle (D).




CHAPTER VII

PROPERTIES OF MATERIALS


A workman is able to select the right metals because he knows that each
has some peculiar property which is best adapted for his particular use.
These with their meaning will now be explained.

ELASTICITY.--This exists in metals in three distinct ways: First, in the
form of _traction_. Hang a weight on a wire and it will stretch a
certain amount. When the weight is removed the wire shrinks back to its
original length.

Second: If the weight on the wire is rotated, so as to twist it, and the
hand is taken from the weight, it will untwist itself, and go back to
its original position. This is called _torsion_.

Third: A piece of metal may be coiled up like a watch spring, or bent
like a carriage spring, and it will yield when pressure is applied. This
is called _flexure_.

Certain kinds of steel have these qualities in a high degree.

TENACITY.--This is a term used to express the resistance which the body
opposes to the separation of its parts. It is determined by forming the
metal into a wire, and hanging on weights, to find how much will be
required to break it. If we have two wires, the first with a transverse
area only one-quarter that of the second, and the first breaks at 25
pounds, while the second breaks at 50 pounds, the tenacity of the first
is twice as great as that of the second.

To the boy who understands simple ratio in mathematics, the problem
would be like this:

25 × 4 : 50 × 1, or as 2 : 1.

THE MOST TENACIOUS METAL.--Steel has the greatest tenacity of all
metals, and lead the least. In proportion to weight, however, there are
many substances which have this property in a higher degree. Cotton
fibers will support millions of times their own weight.

There is one peculiar thing, that tenacity varies with the form of the
body. A solid cylindrical body has a greater strength than a square one
of the same size; and a hollow cylinder more tenacity than a solid one.
This principle is well known in the bones of animals, in the feathers of
birds, and in the stems of many plants.

In almost every metal tenacity diminishes as the temperature increases.

DUCTILITY.--This is a property whereby a metal may be drawn out to form
a wire. Some metals, like cast iron, have absolutely no ductility. The
metal which possesses this property to the highest degree, is platinum.
Wires of this metal have been drawn out so fine that over 30,000 of them
laid side by side would measure only one inch across, and a mile of such
wire would weigh only a grain, or one seven-thousandth of a pound.

MALLEABILITY.--This is considered a modification of ductility. Any
metal which can be beaten out, as with a hammer, or flattened into
sheets with rollers, is considered malleable. Gold possesses this
property to the highest degree. It has been beaten into leaves one
three-hundred-thousandth of an inch thick.

HARDNESS.--This is the resistance which bodies offer to being scratched
by others. As an example, the diamond has the capacity to scratch all,
but cannot be scratched by any other.

ALLOYS.--Alloys, that is a combination of two or more metals, are harder
than the pure metals, and for this reason jewelry, and coins, are
usually alloyed.

The resistance of a body to compression does not depend upon its
hardness. Strike a diamond with a hammer and it flies to pieces, but
wood does not. One is brittle and the other is tough.

The machinist can utilize this property by understanding that velocity
enables a soft material to cut a harder one. Thus, a wrought iron disc
rotating rapidly, will cut such hard substances as agate or quartz.

RESISTANCE.--All metals offer more or less resistance to the flow of an
electric current. Silver offers the least resistance, and German silver
the greatest. Temperature also affects the flow. It passes more easily
over a cold than a warm conductor.

PERSISTENCE.--All metals on receiving heat, will retain it for a certain
length of time, and will finally cool down to the temperature of the
surrounding atmosphere. Some, like aluminum, retain it for a long time;
others, as iron, will give it off quickly.

CONDUCTIVITY.--All metals will conduct heat and cold, as well as
electricity. If one end of a metal bar is heated, the heat creeps along
to the other end until it has the same temperature throughout. This is
called _equalization_.

If a heated bar is placed in contact with another, the effect is to
increase the temperature of the cold bar and lower that of the warm bar.
This is called _reciprocity_.

MOLECULAR FORCES.--_Molecular_ attraction is a force which acts in such
a way as to bring all the particles of a body together. It acts in
three ways, dependent on the particular conditions which exist.

First: _Cohesion_. This exists between molecules which are of the same
kind, as for instance, iron. Cohesion of the particles is very strong in
solids, much weaker in liquids, and scarcely exists at all between the
particles in gases.

Second: _Adhesion_ is that property which exists between the surfaces of
bodies in contact. If two flat surfaces are pressed together, as for
instance, two perfectly smooth and flat pieces of lead, they will
adhere. If, for instance, oil should be put on the surfaces, before
putting them together, they would adhere so firmly that it would be
difficult to pull them apart.

Third: _Affinity_. This is another peculiarity about materials. Thus,
while cohesion binds together the molecules of water, it is chemical
affinity which unites two elements, like hydrogen and oxygen, of which
water is composed.

POROSITY.--All matter has little hollows or spaces between the
molecules. You know what this is in the case of a sponge, or pumice
stone. Certain metals have the pores so small that it is difficult to
see them except with a very powerful glass. Under great pressure water
can be forced through the pores of metals, as has been done in the case
of gold. Water also is porous, but the spaces between the molecules are
very small.

COMPRESSIBILITY.--It follows from the foregoing statement, that if there
are little interstices between the molecules, the various bodies can be
compressed together. This can be done in varying degrees with all
solids, but liquids, generally, have little compressibility. Gases are
readily reduced in volume by compression.

ELASTICITY.--This is a property by virtue of which a body resumes its
original form when compressed. India rubber, ivory and glass are
examples of elasticity; whereas, lead and clay do not possess this
property. Air is the most elastic of all substances.

INERTIA.--This is a property of matter by virtue of which it cannot of
itself change its state of motion or of rest.

Newton's first law of motion is, in substance, that matter at rest will
eternally remain at rest, and matter in motion will forever continue in
motion, unless acted on by some external force.

A rider is carried over the head of a horse when the latter suddenly
stops. This illustrates the inertia of movement. A stone at rest will
always remain in that condition unless moved by some force. That shows
the inertia of rest.

MOMENTUM.--This is the term to designate the quantity of motion in a
body. This quantity varies and is dependent on the mass, together with
the velocity. A fly wheel is a good example. It continues to move after
the impelling force ceases; and a metal wheel has greater momentum than
a wooden wheel at the same speed, owing to its greater mass.

If, however, the wooden wheel is speeded up sufficiently it may have the
same momentum as the metal one.

WEIGHT.--All substances have what is called _weight_. This means that
everything is attracted toward the earth by the force of gravity.
Gravity, however, is different from weight. All substances attract each
other; not only in the direction of the center of the earth, but
laterally, as well.

Weight, therefore, has reference to the pull of an object toward the
earth; and gravity to that influence which all matter has for each other
independently of the direction.

CENTRIPETAL FORCE.--This attraction of the earth, which gives articles
the property of weight, is termed centripetal force--that is, the
drawing in of a body.

CENTRIFUGAL FORCE.--The direct opposite of centripetal, is centrifugal
force, which tends to throw outwardly. Dirt flying from a rapidly
moving wheel illustrates this.

CAPILLARY ATTRACTION.--There is a peculiar property in liquids, which
deserves attention, and should be understood, and that is the name given
to the tendency of liquids to rise in fine tubes.

It is stated that water will always find its level. While this is true,
we have an instance where, owing to the presence of a solid, made in a
peculiar form, causes the liquid, within, to rise up far beyond the
level of the water.

This may be illustrated by three tubes of different internal diameters.
The liquid rises up higher in the second than in the first, and still
higher in the third than in the second. The smaller the tube the greater
the height of the liquid.

This is called _capillary attraction_, the word capillary meaning a
hair. The phenomena is best observed when seen in tubes which are as
fine as hairs. The liquid has an affinity for the metal, and creeps up
the inside, and the distance it will thus move depends on the size of
the tube.

THE SAP OF TREES.--The sap of trees goes upwardly, not because the tree
is alive, but due to this property in the contact of liquids with a
solid. It is exactly on the same principle that if the end of a piece of
blotting paper is immersed in water, the latter will creep up and
spread over the entire surface of the sheet.

In like manner, oil moves upwardly in a wick, and will keep on doing so,
until the lighted wick is extinguished, when the flow ceases. When it is
again lighted the oil again flows, as before.

If it were not for this principle of capillary attraction, it would be
difficult to form a bubble of air in a spirit level. You can readily see
how the liquid at each end of the air bubble rounds it off, as though it
tried to surround it.

SOUND.--Sound is caused by vibration, and it would be impossible to
convey it without an elastic medium of some kind.

_Acoustics_ is a branch of physics which treats of sounds. It is
distinguished from music which has reference to the particular kinds.

_Sounds_ are distinguished from _noises_. The latter are discordant and
abrupt vibrations, whereas the former are regular and continuous.

SOUND MEDIUMS.--Gases, vapors, liquids and solids transmit vibrations,
but liquids and solids propagate with greater velocity than gases.

VIBRATION.--A vibration is the moving to and fro of the molecules in a
body, and the greater their movement the more intense is the sound. The
intensity of the sound is affected by the density of the atmosphere, and
the movement of the winds also changes its power of transmission.

Sound is also made more intense if a sonorous body is near its source.
This is taken advantage of in musical instruments, where a
sounding-board is used, as in the case of the piano, and in the violin,
which has a thin shell as a body for holding the strings.

Another curious thing is shown in the speaking tube, where the sound
waves are confined, so that they are carried along in one line, and as
they are not interfered with will transmit the vibrations to great
distances.

VELOCITY OF SOUND.--The temperature of the air has also an effect on the
rate of transmission, but for general purposes a temperature of 62
degrees has been taken as the standard. The movement is shown to be
about 50 miles in 4 minutes, or at the rate of 1,120 feet per second.

In water, however, the speed is four times greater; and in iron nearly
fifteen times greater. Soft earth is a poor conductor, while rock and
solid earth convey very readily. Placing the ear on a railway track will
give the vibrations of a moving train miles before it can be heard
through the air.

SOUND REFLECTIONS.--Sound waves move outwardly from the object in the
form of wave-like rings, but those concentric rings, as they are
called, may be interrupted at various points by obstacles. When that is
the case the sound is buffeted back, producing what is called echoes.

RESONANCE.--Materials have a quality that produces a very useful result,
called _resonance_, and it is one of the things that gives added effect
to a speaker's voice in a hall, where there is a constant succession of
echoes. A wall distant from the speaker about 55 feet, produces an
almost instantaneous reflection of the sound, and at double that
measurement the effect is still stronger. When the distance is too short
for the reflecting sound to be heard, we have _resonance_. It enriches
the sound of the voice, and gives a finer quality to musical
instruments.

ECHOES.--When sounds are heard after the originals are emitted they tend
to confusion, and the quality of resonance is lost. There are places
where echoes are repeated many times. In the chateau of Simonetta,
Italy, a sound will be repeated thirty times.

SPEAKING TRUMPET.--This instrument is an example of the use of
reflection. It is merely a bell-shaped, or flaring body, the large end
of which is directed to the audience. The voice talking into the small
end is directed forwardly, and is reflected from the sides, and its
resonance also enables the vibrations to carry farther than without the
use of the solid part of the instrument.

The ear trumpet is an illustration of a sound-collecting device, the
waves being brought together by reflection.

THE STETHOSCOPE.--This is an instrument used by physicians, and it is so
delicate that the movements of the organs of the body can be heard with
great distinctness. It merely collects the vibrations, and transmits
them to the ears by the small tubes which are connected with the
collecting bell.

THE VITASCOPE.--Numerous instruments have been devised to determine
the rate of vibration of different materials and structures, the most
important being the _vitascope_, which has a revolvable cylinder,
blackened with soot, and this being rotated at a certain speed, the
stylus, which is attached to the vibrating body, in contact with the
cylinder, will show the number per second, as well as the particular
character of each oscillation.

THE PHONAUTOGRAPH.--This instrument is used to register the vibration of
wind instruments, as well as the human voice, and the particular forms
of the vibrations are traced on a cylinder, the tracing stylus being
attached to a thin vibrating membrane which is affected by the voice or
instrument.

THE PHONOGRAPH.--This instrument is the outgrowth of the stylus forms of
the apparatus described, but in this case the stylus, or needle, is
fixed to a metallic diaphragm, and its point makes an impression on
suitable material placed on the outside of a revolvable cylinder or
disc.

Light.-Light is the agent which excites the sensation of vision in the
eye. Various theories have been advanced by scientists to account for
the phenomenon, and the two most noted views are the _corpuscular_,
promulgated by Sir Isaac Newton, and the _undulatory_, enunciated by
Huygens and Euler.

The _corpuscular_ theory conceives that light is a substance of
exceedingly light particles which are shot forth with immense velocity.
The _undulatory_ theory, now generally accepted, maintains that light is
carried by vibrations in ether. Ether is a subtle elastic medium which
fills all space.

_Luminous_ bodies are those like the sun, which emit light. Rays may
_diverge_, that is, spread out; _converge_, or point toward each other;
or they may be _parallel_ with each other.

VELOCITY OF LIGHT.--Light moves at the rate of about 186,000 miles a
second. As the sun is about 94,000,000 miles from the earth, it takes
8-1/2 minutes for the light of the sun to reach us.

REFLECTION.--One of the most important things connected with light is
that of reflection. It is that quality which is utilized in telescopes,
microscopes, mirrors, heliograph signaling and other like apparatus and
uses. The underlying principle is, that a ray is reflected, or thrown
back from a mirror at the same angle as that which produces the light.

When the rays of the sun, which are, of course, parallel, strike a
concave mirror, the reflecting rays are converged; and when the rays
strike a convex mirror they diverge. In this way the principle is
employed in reflecting telescopes.

REFRACTION.--This is the peculiar action of light in passing through
substances. If a ray passes through water at an angle to the surface the
ray will bend downwardly in passing through, and then again pass on in a
straight line. This will be noticed if a pencil is stood in a glass of
water at an angle, when it will appear bent.

Refraction is that which enables light to be divided up, or analyzed. In
this way white light from the sun is shown to be composed of seven
principal colors.

COLORS.--If the light is passed through a prism, which is a triangularly
shaped piece of glass, the rays on emerging will diverge from each
other, and when they fall on a wall or screen the colors red, orange,
yellow, green, blue, indigo and violet are shown.

The reason for this is that the ray in passing through the prism has the
different colors in it refract at different angles, the violet bending
more than the red.

THE SPECTROSCOPE.--The ability to make what is thus called a _spectrum_,
brought forth one of the most wonderful instruments ever devised by man.
If any metal, or material, is fused, or put in such a condition that a
ray of light can be obtained from it, and this light is passed through a
prism, it will be found that each substance has its own peculiar
divisions and arrangements of colors.

In this way substances are determined by what is called _spectrum
analysis_, and it is by means of this instrument that the composition of
the sun, and the planets and fixed stars are determined.

THE RAINBOW.--The rainbow is one of the effects of refraction, as the
light, striking the little globular particles of water suspended in the
air, produces a breaking up of the white light into its component
colors, and the sky serves as a background for viewing the analysis thus
made.

HEAT.--It is now conclusively proven, that heat, like light, magnetism
and electricity, is merely a mode of motion.

The _mechanical_ theory of heat may be shown by rubbing together several
bodies. Heat expands all substances, except ice, and in expanding
develops an enormous force.

EXPANSION.--In like manner liquids expand with heat. The power of
mercury in expanding may be understood when it is stated that a pressure
of 10,000 pounds would be required to prevent the expansion of mercury,
when heated simply 10 degrees.

Gases also expand. While water, and the different solids, all have their
particular units of expansion, it is not so with gases, as all have the
same coefficient.




CHAPTER VIII

HOW DRAUGHTING BECOMES A VALUABLE AID


The ability to read drawings is a necessary part of the boy's education.
To know how to use the tools, is still more important. In conveying an
idea about a piece of mechanism, a sketch is given. Now, the sketch may
be readable in itself, requiring no explanation, or it may be of such a
nature that it will necessitate some written description.

[Illustration: _Fig. 95. Plain Circle_]

LINES IN DRAWING.--In drawing, lines have a definite meaning. A plain
circular line, like Fig. 95, when drawn in that way, conveys three
meanings: It may represent a rim, or a bent piece of wire; it may
illustrate a disk; or, it may convey the idea of a ball.

Suppose we develop them to express the three forms accurately. Fig. 96,
by merely adding an interior line, shows that it is a rim. There can be
no further doubt about that expression.

Fig. 97 shows a single line, but it will now be noticed that the line is
thickened at the lower right-hand side, and from this you can readily
infer that it is a disk.

SHADING.--Fig. 98, by having a few shaded lines on the right and lower
side, makes it have the appearance of a globe or a convex surface.

[Illustration: _Fig. 96. Ring_
_Fig. 97. Raised Surface_
_Fig. 98. Sphere_]

Shading or thickening the lines also gives another expression to the
same circular line.

In Fig. 99, if the upper and left-hand side of the circle is heavily
shaded, it shows that the area within the circle is depressed, instead
of being raised.

DIRECTION OF SHADE.--On the other hand, if the shading lines, as in Fig.
100, are at the upper left-hand side, then the mind at once grasps the
idea of a concave surface.

The first thing, therefore, to keep in mind, is this fact: That in all
mechanical drawing, the light is supposed to shine down from the upper
left-hand corner and that, as a result, the lower vertical line, as well
as the extreme right-hand vertical line, casts the shadows, and should,
therefore, be made heavier than the upper horizontal, and the left-hand
vertical lines.

[Illustration: _Fig. 99. Depressed Surface_ _Fig. 100. Concave_]

There are exceptions to this rule, which will be readily understood by
following out the illustrations in the order given below.

PERSPECTIVES.--The utility of the heavy lines will be more apparent when
drawing square, rectangular, or triangular objects.

Let us take Fig. 101, which appears to be the perspective of a cube.
Notice that all lines are of the same thickness. When the sketch was
first brought to me I thought it was a cube; but the explanation which
followed, showed that the man who made the sketch had an entirely
different meaning.

He had intended to convey to my mind the idea of three pieces, A, B, C,
of metal, of equal size, joined together so as to form a triangularly
shaped pocket as shown in Fig. 101. The addition of the inner lines,
like D, quickly dispelled the suggestion of the cube.

[Illustration: _Fig. 101. Fig. 102. Fig. 103. Fig. 104.
 Forms of Cubical Outlines_]

"But," he remarked, "I want to use the thinnest metal, like sheets of
tin; and you show them thick by adding the inner lines."

Such being the case, if we did not want to show thickness as its
structural form, we had to do it by making the lines themselves and the
shading give that structural idea. This was done by using the single
lines, as in Fig. 103, and by a slight shading of the pieces A, B, C.

[Illustration: _Fig. 105. Fig. 106. Shading Edges_]

THE MOST PRONOUNCED LINES.--If it had been a cube, or a solid block, the
corners nearest the eye would have been most pronounced, as in Fig. 104,
and the side next to the observer would have been darkest.

This question of light and shadow is what expresses the surface
formation of every drawing. Simple strokes form outlines of the object,
but their thickness, and the shading, show the character enclosed by the
LINES. DIRECTION OF LIGHT.--Now, as stated, the casting of the shadow
downward from the upper left-hand corner makes the last line over which
it passes the thickest, and in Figs. 105 and 106 they are not the
extreme lines at the bottom and at the right side, because of the close
parallel lines.

In Figs. 109 and 110 the blades superposed on the other are very thin,
and the result is the lines at the right side and bottom are made much
heavier.

[Illustration: _Fig. 107. Fig. 108. Illustrating Heavy Lines_]

This is more fully shown in Figs. 107 and 108. Notice the marked
difference between the two figures, both of which show the same set of
pulleys, and the last figure, by merely having the lower and the
right-hand lines of each pulley heavy, changes the character of the
representation, and tells much more clearly what the draughtsman sought
to convey.

SCALE DRAWINGS.--All drawings are made to a scale where the article is
large and cannot be indicated the exact size, using parts of an inch to
represent inches; and parts of a foot to represent feet.

In order to reduce a drawing where a foot is the unit, it is always best
to use one-and-a-half inches, or twelve-eighths of an inch, as the
basis. In this way each eighth of an inch represents an inch. If the
drawing should be made larger, then use three inches, and in that way
each inch would be one-quarter of an inch.

[Illustration: _Fig. 109. Fig. 110. Lines on Plain Surfaces_]

The drawing should then have marked, in some conspicuous place, the
scale, like the following: "Scale, 1-1/2" = 1'"; or, "Scale 3" = 1'."

DEGREE, AND WHAT IT MEANS.--A degree is not a measurement. The word is
used to designate an interval, a position, or an angle. Every circle has
360 degrees, and when a certain degree is mentioned, it means a certain
angle from what is called a _base line_.

[Illustration: _Fig. 111. Illustrating Degrees_]

Look at Fig. 111. This has a vertical line A, and a horizontal line B.
The circle is thus divided into four parts, and where these lines A, B,
cross the circle are the cardinal points. Each of the four parts is
called a quadrant, and each quadrant has 90 degrees.

Any line, like C, which is halfway between A and B, is 45 degrees.
Halfway between A and C, or between B and C, like the line D, is 22-1/2
degrees.

MEMORIZING ANGLES.--It is well to try and remember these lines by fixing
the angles in the memory. A good plan is to divide any of the quadrants
into thirds, as shown by the points E, F, and then remember that E is 30
degrees from the horizontal line B, and that F is 60 degrees. Or, you
might say that F is 30 degrees from the vertical line A, and E 60
degrees from A. Either would be correct.

[Illustration: _Fig. 112. Section Lining_]

SECTION LINING.--In representing many parts of a machine, or article, it
is necessary to show the parts cut off, which must be illustrated by
what is called "section lining." Adjacent parts should have the section
lines running at right angles to each other, and always at 45 degrees.

Look at the outside and then the inside views of Fig. 112, and you will
see how the contiguous parts have the angles at right angles, and
clearly illustrate how every part of the wrench is made. Skill in
depicting an article, for the purpose of constructing it from the
drawing, will make the actual work on the bench and lathe an easy one.

[Illustration: _Fig. 113. Drawing an Ellipse_]

MAKING ELLIPSES AND IRREGULAR CURVES.--This is the hardest thing to do
with drawing tools. A properly constructed elliptical figure is
difficult, principally, because two different sized curves are
required, and the pen runs from one curve into the other. If the two
curves meet at the wrong place, you may be sure you will have a
distorted ellipse.

Follow the directions given in connection with Fig. 113, and it will
give you a good idea of merging the two lines.

First. Draw a horizontal line, A, which is in the direction of the major
axis of the ellipse--that is, the longest distance across. The narrow
part of the ellipse is called the minor axis.

Second. Draw a perpendicular line, B, which we will call the center of
the ellipse, where it crosses the line A. This point must not be
confounded with the _focus_. In a circle the focus is the exact center
of the ring, but there is no such thing in an ellipse. Instead, there
are two focal points, called the _foci_, as you will see presently.

Third. Step off two points or marking places, as we shall term them,
equidistant from the line B, and marked C, C. These marks will then
represent the diameter of the ellipse across its major axis.

Fourth. We must now get the diameter of the minor axis, along the line
B. This distance will depend on the perspective you have of the figure.
If you look at a disk at an angle of about 30 degrees it will be half of
the distance across the major axis.

So you may understand this examine Fig. 114. The first sketch shows the
eye looking directly at the disk 1. In the second sketch the disk is at
30 degrees, and now the lines 2 2, from the eye, indicate that it is
just half the width that it was when the lines 3 3 were projected. The
marks D D, therefore, indicate the distance across the minor axis in
Fig. 113.

[Illustration: _Fig. 114. Perspection in Angles_]

Fifth. We must now find the focal points of the ellipse. If the line A
on each side of the cross line B is divided into four parts, the outer
marks E may be used for the foci, and will be the places where the point
of the compass, or bow pen, is to be placed.

Sixth. Describe a circle F, so it passes through the mark C, and move
the point of the compass to the center of the ellipse, at the star, and
describe a circle line G, from the mark C to the line B. This will give
a centering point H. Then draw a line I from H to E, and extend it
through the circle F.

Seventh. If the point of the compass is now put at H, and the pencil or
pen on the circle line F, the curve J can be drawn, so the latter curve
and the curve F will thus merge perfectly at the line I.

THE FOCAL POINTS.--The focal points can be selected at any arbitrary
point, between C and the line B, and the point H may be moved closer to
or farther away from the line A, and you will succeed in making the
ellipse correct, if you observe one thing, namely: The line I, which
must always run from H to E, and intersects the circle F, is the
starting or the ending point for the small curve F or the large circle
J.

[Illustration: _Fig. 115. Fig. 116. Fig. 117. Perspectives of Cubes_]

ISOMETRIC AND PERSPECTIVE.--A figure may be drawn so as to show an
isometric or a perspective view. Thus, a cube can be drawn so as to make
an isometric figure, as in Fig. 115, where the three sides are equal to
each other.

Isometric means a method of drawing any object in such a manner that the
height, length and breadth may be shown in the proportion they really
bear to each other. Fig. 115 has the sides not only equal to each other,
in appearance to the eye, but they have the same outlines and angles.

Contrast this figure with Figs. 116 and 117. In Fig. 116 two of the
sides are equal in angles and outline; and in Fig. 117 each side has a
different outline, and different angles. Nevertheless, all the cubes
are, in reality, of the same dimension.

THE PROTRACTOR.--This is a most useful tool for the draughtsman. It
enables the user to readily find any angle. Fig. 118 shows an approved
form of the tool for this purpose.

[Illustration: _Fig. 118. Protractor. Section Lining Metals_]

SUGGESTIONS IN DRAWING.--As in the use of all other tools, so with the
drawing instrument, it must be kept in proper order. If the points are
too fine they will cut the paper; if too blunt the lines will be ragged.
In whetting the points hold the pen at an angle of 12 degrees. Don't
make too long an angle or slope, and every time you sharpen hold it at
the same angle, so that it is ground back, and not at the point only.

[Illustration: _Fig. 119. Using the Protractor._]

HOLDING THE PEN.--The drawing pen should be held as nearly vertical as
possible. Use the cleaning rag frequently. If the ink does not flow
freely, after you have made a few strokes, as is frequently the case,
gently press together the points. The least grit between the tines will
cause an irregular flow.

INKS.--As prepared liquid inks are now universally used, a few
suggestions might be well concerning them. After half the bottle has
been used, add a half teaspoonful of water, shake it well, and then
strain it through a fine cotton cloth. This will remove all grit and
lint that is sure to get into the bottle however carefully it may be
corked.

[Illustration: _Fig. 120. Section Lining Metals_]

TRACING CLOTH.--It is preferable to use the dull side of the tracing
cloth for the reasons that, as the cloth is rolled with the glossy side
inside, the figure when drawn on the other side will be uppermost, and
will thus lie flat; and on the other hand, the ink will take better on
the dull side.

If the ink does not flow freely, use chalk, fine pumice stone, or talc,
and rub it in well with a clean cloth, and then wipe off well before
beginning to trace.

DETAIL PAPER.--The detail paper, on which the drawing is first made in
pencil, should show the figure accurately, particularly the points where
the bow pen are to be used, as well as the measurement points for the
straight lines.

HOW TO PROCEED.--Make the circles, curves, and irregular lines first,
and then follow with the straight lines. Where the point of the circle
pen must be used for a large number of lines, as, for instance, in
shading, the smallest circles should be made first, and the largest
circles last, because at every turn the centering hole becomes larger,
and there is liability to make the circles more or less irregular. Such
irregularity will not be so noticeable in the large curves as in the
smaller ones.

INDICATING MATERIAL BY THE SECTION LINES.--In section lining different
materials can be indicated by the character of the lines, shown in Fig.
120.




CHAPTER IX

TREATMENT AND USE OF METALS


ANNEALING.--A very important part of the novice's education is a
knowledge pertaining to the annealing of metals. Unlike the artisan in
wood, who works the materials as he finds them, the machinist can, and,
in fact, with many of the substances, must prepare them so they can be
handled or cut by the tools.

Annealing is one of the steps necessary with all cutting tools, and it
is an absolute requirement with many metals for ordinary use, as well as
for many other articles like glass. This is particularly true in the use
of copper.

TOUGHNESS AND ELASTICITY.--It means the putting of metals in such a
condition that they will not only be less brittle, but also tougher and
more elastic. Many substances, like glass, must be annealed before they
can be put in condition for use, as this material when first turned out
is so brittle that the slightest touch will shatter it, so that it must
be toughened.

Malleable or wrought iron, if subjected to pressure, becomes brittle,
and it is necessary to anneal it. Otherwise, if used, for instance, for
boiler plates, from the rolled sheets, it would stand but little
pressure.

The most immediate use the boy will have is the treatment of steel. He
must learn the necessity of this process, and that of tempering, in all
his cutting tools, and in the making of machinery where some parts are
required to be constructed of very hard metal.

THE PROCESS.--To anneal steel it must be heated to a bright cherry red
and then gradually cooled down. For this purpose a bed of fine charcoal,
or iron filings and lime, is prepared, in which the article is embedded,
and permitted to remain until it is cold.

There are many ways of doing the work, particularly in the use of
substances which will the most readily give up their carbon to the tool.
Yellow prussiate of potash is an excellent medium, and this is sprinkled
over the cherry-heated article to be annealed. The process may be
repeated several times.

TEMPERING.--This is the reverse of annealing as understood in the art.
The word itself does not mean to "harden," but to put into some
intermediate state. For instance, "tempered clay" means a clay which has
been softened so it can be readily worked.

On the other hand, a tempered steel tool is put into a condition where
it is hardened, but this hardness is also accompanied by another
quality, namely, _toughness_. For this reason, the word _temper_, and
not _hardness_, is referred to. A lathe tool, if merely hardened, would
be useless for that purpose.

TEMPERING CONTRASTED WITH ANNEALING.--It will be observed that in
annealing three things are necessary: First, heating to a certain
temperature; second, cooling slowly; third, the particular manner of
cooling it.

In tempering, on the other hand, three things are also necessary:

First: The heating temperature should be a dull red, which is less than
the annealing heat.

Second: Instead of cooling slowly the article tempered is dipped into a
liquid which suddenly chills it.

Third: The materials used vary, but if the article is plunged into an
unguent made of mercury and bacon fat, it will impart a high degree of
toughness and elasticity.

MATERIALS USED.--Various oils, fats and rosins are also used, and some
acids in water are also valuable for this purpose. Care should be taken
to have sufficient amount of liquid in the bath so as not to evaporate
it or heat it up too much when it receives the heated body.

Different parts of certain articles require varying degrees of hardness,
like the tangs of files. The cutting body of the file must be extremely
hard, and rather brittle than tough. If the tang should be of the same
hardness it would readily break.

_Gradual Tempering._--To prevent this, some substance like soap suds may
be used to cool down the tang, so that toughness without hardness is
imparted.

The tempering, or hardening, like the annealing process, may be repeated
several times in succession, and at each successive heating the article
is put at a higher temperature.

If any part of a body, as, for instance, a hammerhead, should require
hardening, it may be plunged into the liquid for a short distance only,
and this will harden the pole or peon while leaving the other part of
the head soft, or annealed.

Glycerine is a good tempering substance, and to this may be added a
small amount of sulphate of potash.

FLUXING.--The word _flux_ means to fuse or to melt, or to put into a
liquid state. The office of a flux is to facilitate the fusion of
metals. But fluxes do two things. They not only aid the conversion of
the metal into a fluid state, but also serve as a means for facilitating
the unity of several metals which make up the alloy, and aid in uniting
the parts of metals to be joined in the welding of parts.

UNITING METALS.--Metals are united in three ways, where heat is used:

First: By heating two or more of them to such a high temperature that
they melt and form a compound, or an alloy, as it is called.

Second: By heating up the points to be joined, and then lapping the
pieces and hammering the parts. This is called forge work or welding.

Third: By not heating the adjacent parts and using an easily fusible
metal, which is heated up and run between the two, by means of a
soldering iron.

The foreign material used in the first is called a flux; in the second
it is termed a welding compound; and in the third it is known as a
soldering acid, or soldering fluid.

The boy is not so much interested in the first process, from the
standpoint of actual work, but it is necessary that he should have some
understanding of it.

It may be said, as to fluxes, generally, that they are intended to
promote the fusion of the liquefying metals, and the elements used are
the alkalis, such as borax, tartar, limestone, or fluor spar.

These substances act as reducing or oxidizing agents. The most important
are carbonate of soda, potash, and cyanide of potassium. Limestone is
used as the flux in iron-smelting.

WELDING COMPOUNDS.--Elsewhere formulas are given of the compounds most
desirable to use. It is obvious that the application of these substances
on the heated surfaces, is not only to facilitate the heating, but to
prepare the articles in such a manner that they will more readily adhere
to each other.

OXIDATION.--Oxidation is the thing to guard against in welding. The
moment a piece of metal, heated to whiteness, is exposed, the air coats
it with a film which is called an _oxide_. To remove this the welding
compound is applied.

The next office of the substance thus applied, is to serve as a medium
for keeping the welding parts in a liquid condition as long as possible,
and thus facilitate the unity of the joined elements.

When the hammer beats the heated metals an additional increment of heat
is imparted to the weld, due to the forcing together of the molecules of
the iron, so that these two agencies, namely, the compound and the
mechanical friction, act together to unite the particles of the metal.

SOLDERING.--Here another principle is involved, namely, the use of an
intermediate material between two parts which are to be united. The
surfaces to be brought together must be thoroughly cleaned, using such
agents as will prevent the formation of oxides.

The parts to be united may be of the same, or of different materials,
and it is in this particular that the workman must be able to make a
choice of the solder most available, and whether hard or soft.

SOFT SOLDER.--A soft solder is usually employed where lead, tin, or
alloys of lead, tin and bismuth are to be soldered. These solders are
all fusible at a low temperature, and they do not, as a result, have
great strength.

Bismuth is a metal which lowers the fusing point of any alloy of which
it forms a part, while lead makes the solder less fusible.

HARD SOLDER.--These are so distinguished because they require a
temperature above the low red to fuse them. The metals which are alloyed
for this purpose are copper, silver, brass, zinc and tin. Various alloys
are thus made which require a high temperature to flux properly, and
these are the ones to use in joining steel to steel, the parts to be
united requiring an intense furnace heat.

SPELTER.--The alloy used for this purpose is termed "spelter," and
brass, zinc and tin are its usual components. The hard solders are used
for uniting brass, bronze, copper, and iron.

Whether soft or hard solder is used, it is obvious that it must melt at
a lower temperature than the parts which are to be joined together.

There is one peculiarity with respect to alloys: They melt at a lower
temperature than either of the metals forming the alloys.

SOLDERING ACID.--Before beginning the work of soldering, the parts must
be cleaned by filing or sandpapering, and coated with an acid which
neutralizes the oxygen of the air.

This is usually muriatic acid, of which use, say, one quart and into
this drop small pieces of zinc. This will effervesce during the time the
acid is dissolving the zinc. When the boiling motion ceases, the liquid
may be strained, or the dark pieces removed.

The next step is to dissolve two ounces of sal ammoniac in a third of a
pint of water, and in another vessel dissolve an ounce of chloride of
tin.

Then mix the three solutions, and this can be placed in a bottle, or
earthen jar or vessel, and it will keep indefinitely.

THE SOLDERING IRON.--A large iron is always better than a small one,
particularly for the reason that it will retain its heat better. This
should always be kept tinned, which can be done by heating and plunging
it into the soldering solution, and the solder will then adhere to the
iron and cover the point, so that when the actual soldering takes place
the solder will not creep away from the tool.

By a little care and attention to these details, the work of uniting
metals will be a pleasure. It is so often the case, however, that the
apparatus for doing this work is neglected in a shop; the acid is
allowed to become dirty and full or foreign matter, and the different
parts separated.




CHAPTER X

ON GEARING AND HOW ORDERED


The technical name for gears, the manner of measuring them, their pitch
and like terms, are most confusing to the novice. As an aid to the
understanding on this subject, the wheels are illustrated, showing the
application of these terms.

SPUR AND PINION.--When a gear is ordered a specification is necessary.
The manufacturer will know what you mean if you use the proper terms,
and you should learn the distinctions between spur and pinion, and why a
bevel differs from a miter gear.

If the gears on two parallel shafts mesh with each other, they both may
be of the same diameter, or one may be larger than the other. In the
latter case, the small one is the pinion, and the larger one the spur
wheel.

Some manufacturers use the word "gear" for "pinion," so that, in
ordering, they call them _gear_ and _pinion_, in speaking of the large
and small wheels.

MEASURING A GEAR.--The first thing to specify would be the diameter. Now
a spur gear, as well as a pinion, has three diameters; one measure
across the outer extremities of the teeth; one measure across the wheel
from the base of the teeth; and the distance across the wheel at a point
midway between the base and end of the teeth.

These three measurements are called, respectively, "outside diameter,"
"inside diameter," and "pitch diameter." When the word _diameter_ is
used, as applied to a gear wheel, it is always understood to mean the
"pitch diameter."

[Illustration: _Fig. 121. Spur Gears_]

PITCH.--This term is the most difficult to understand. When two gears of
equal size mesh together, the pitch line, or the _pitch circle_, as it
is also called, is exactly midway between the centers of the two
wheels.

Now the number of teeth in a gear is calculated on the pitch line, and
this is called:

[Illustration: _Fig. 122. Miter Gear Pitch_]

DIAMETRAL PITCH.--To illustrate: If a gear has 40 teeth, and the pitch
diameter of the wheel is 4 inches, there are 10 teeth to each inch of
the pitch diameter, and the gear is then 10 _diametral pitch_.

CIRCULAR PITCH.--Now the term "circular pitch" grows out of the
necessity of getting the measurement of the distance from the center of
one tooth to the center of the next, and it is measured along the pitch
line.

Supposing you wanted to know the number of teeth in a gear where the
pitch diameter and the diametral pitch are given. You would proceed as
follows: Let the diameter of the pitch circle be 10 inches, and the
diameter of the diametral pitch be 4 inches. Multiplying these together
the product is 40, thus giving the number of teeth.

[Illustration: _Fig. 123. Bevel Gears._]

It will thus be seen that if you have an idea of the diametral pitch and
circular pitch, you can pretty fairly judge of the size that the teeth
will be, and thus enable you to determine about what kind of teeth you
should order.

HOW TO ORDER A GEAR.--In proceeding to order, therefore, you may give
the pitch, or the diameter of the pitch circle, in which latter case the
manufacturer of the gear will understand how to determine the number of
the teeth. In case the intermeshing gears are of different diameters,
state the number of teeth in the gear and also in the pinion, or
indicate what the relative speed shall be.

[Illustration: _Fig. 124. Miter Gears._]

This should be followed by the diameter of the hole in the gear and also
in the pinion; the backing of both gear and pinion; the width of the
face; the diameter of the gear hub; diameter of the pinion hub; and,
finally, whether the gears are to be fastened to the shafts by key-ways
or set-screws.

Fig. 122 shows a sample pair of miter gears, with the measurements to
indicate how to make the drawings. Fig. 123 shows the bevel gears.

BEVEL AND MITER GEARS.--When two intermeshing gears are on shafts which
are at right angles to each other, they may be equal diametrically, or
of different sizes. If both are of the same diameter, they are called
bevel gears; if of different diameters, miter gears.

[Illustration: _Fig. 125. Sprocket Wheel._]

It is, in ordering gears of this character, that the novice finds it
most difficult to know just what to do. In this case it is necessary to
get the proper relation of speed between the two gears, and, for
convenience, we shall, in the drawing, make the gears in the relation of
2 to 1.

DRAWING GEARS.--Draw two lines at right angles, Fig. 124, as 1 and 2,
marking off the sizes of the two wheels at the points 3, 4. Then draw a
vertical line (A) midway between the marks of the line 2, and this will
be the center of the main pinion.

Also draw a horizontal line (B) midway between the marks on the vertical
line (1), and this will represent the center of the small gear. These
two cross lines (A, B) constitute the intersecting axes of the two
wheels, and a line (5), drawn from the mark (3 to 4), and another line
(6), from the axes to the intersecting points of the lines (1, 2), will
give the pitch line angles of the two wheels.

SPROCKET WHEELS.--For sprocket wheels the pitch line passes centrally
through the rollers (A) of the chain, as shown in Fig. 125, and the
pitch of the chain is that distance between the centers of two adjacent
rollers. In this case the cut of the teeth is determined by the chain.




CHAPTER XI

MECHANICAL POWERS


THE LEVER.--The lever is the most wonderful mechanical element in the
world. The expression, _lever_, is not employed in the sense of a stick
or a bar which is used against a fulcrum to lift or push something with,
but as the type of numerous devices which employ the same principle.

Some of these devices are, the wedge, the screw, the pulley and the
inclined plane. In some form or other, one or more of these are used in
every piece of mechanism in the world.

Because the lever enables the user to raise or move an object hundreds
of times heavier than is possible without it, has led thousands of
people to misunderstand its meaning, because it has the appearance, to
the ignorant, of being able to manufacture power.

WRONG INFERENCES FROM USE OF LEVER.--This lack of knowledge of first
principles, has bred and is now breeding, so-called perpetual motion
inventors (?) all over the civilized world. It is surprising how many
men, to say nothing of boys, actually believe that power can be made
without the expenditure of something which equalizes it.

The boy should not be led astray in this particular, and I shall try to
make the matter plain by using the simple lever to illustrate the fact
that whenever power is exerted some form of energy is expended.

In Fig. 126 is a lever (A), resting on a fulcrum (B), the fulcrum being
so placed that the lever is four times longer on one side than on the
other. A weight (C) of 4 pounds is placed on the short end, and a
1-pound weight (D), called the _power_, on the short end. It will thus
be seen that the lever is balanced by the two weights, or that the
_weight_ and the _power_ are equal.

[Illustration: _Fig. 126. Simple Lever_]

THE LEVER PRINCIPLE.--Now, without stopping to inquire, the boy will
say: "Certainly, I can understand that. As the lever is four times
longer on one side of the fulcrum than on the other side, it requires
only one-fourth of the weight to balance the four pounds. But suppose I
push down the lever, at the point where the weight (D) is, then, for
every pound I push down I can raise four pounds at C. In that case do I
not produce four times the power?"

I answer, yes. But while I produce that power I am losing something
which is equal to the power gained. What is that?

[Illustration: _Fig. 127. Lever Action_]

First: Look at Fig. 127; the distance traveled. The long end of the
lever is at its highest point, which is A; and the short end of the
lever is at its lowest point C. When the long end of the lever is pushed
down, so it is at B, it moves four times farther than the short end
moves upwardly, as the distance from C to D is just one-fourth that from
A to B. The energy expended in moving four times the distance balances
the power gained.

POWER VS. DISTANCE TRAVELED.--From this the following law is deduced:
That whatever is gained in power is lost in the distance traveled.

Second: Using the same figure, supposing it was necessary to raise the
short end of the lever, from C to D, in one second of time. In that case
the hand pressing down the long end of the lever, would go from A to B
in one second of time; or it would go four times as far as the short
end, in the same time.

POWER VS. LOSS IN TIME.--This means another law: That what is gained in
power is lost in time.

Distinguish clearly between these two motions. In the first case the
long end of the lever is moved down from A to B in four seconds, and it
had to travel four times the distance that the short end moves in going
from C to D.

In the second case the long end is moved down, from A to B, in one
second of time, and it had to go that distance in one-fourth of the
time, so that four times as much energy was expended in the same time to
raise the short end from C to D.

WRONGLY DIRECTED ENERGY.--More men have gone astray on the simple
question of the power of the lever than on any other subject in
mechanics. The writer has known instances where men knew the principles
involved in the lever, who would still insist on trying to work out
mechanical devices in which pulleys and gearing were involved, without
seeming to understand that those mechanical devices are absolutely the
same in principle.

This will be made plain by a few illustrations. In Fig. 128, A is a
pulley four times larger, diametrically, than B, and C is the pivot on
which they turn. The pulleys are, of course, secured to each other. In
this case we have the two weights, one of four pounds on the belt, which
is on the small pulley (B), and a one-pound weight on the belt from the
large pulley (A).

[Illustration: _Fig. 128. The Pulley_]

THE LEVER AND THE PULLEY.--If we should substitute a lever (D) for the
pulleys, the similarity to the lever (Fig. 127) would be apparent at
once. The pivot (C) in this case would act the same as the pivot (C) in
the lever illustration.

In the same manner, and for like reasons, the wedge, the screw and the
incline plane, are different structural applications of the principles
set forth in the lever.

Whenever two gears are connected together, the lever principle is used,
whether they are the same in size, diametrically, or not. If they are
the same size then no change in power results; but instead, thereof, a
change takes place in the direction of the motion.

[Illustration: _Fig. 129. Fig. 130. Change of Direction_]

When one end of the lever (A) goes down, the other end goes up, as shown
in Fig. 129; and in Fig. 130, when the shaft (C) of one wheel turns in
one direction, the shaft of the other wheel turns in the opposite
direction.

It is plain that a gear, like a lever, may change direction as well as
increase or decrease power. It is the thorough knowledge of these facts,
and their application, which enables man to make the wonderful machinery
we see on every hand.

SOURCES OF POWER.--Power is derived from a variety of sources, but what
are called the _prime movers_ are derived from heat, through the various
fuels, from water, from the winds and from the tides and waves of the
ocean. In the case of water the power depends on the head, or height, of
the surface of the water above the discharging orifice.

WATER POWER.--A column of water an inch square and 28 inches high gives
a pressure at the base of one pound; and the pressure at the lower end
is equal in all directions. If a tank of water 28 inches high has a
single orifice in its bottom 1" x 1" in size, the pressure of water
through that opening will be only one pound, and it will be one pound
through every other orifice in the bottom of the same size.

CALCULATING FUEL ENERGY.--Power from fuels depends upon the expansion of
the materials consumed, or upon the fact that heat expands some element,
like water, which in turn produces the power. One cubic inch of water,
when converted into steam, has a volume equal to one cubic foot, or
about 1,700 times increase in bulk.

Advantage is taken of this in steam engine construction. If a cylinder
has a piston in it with an area of 100 square inches, and a pipe one
inch square supplies steam at 50 pounds pressure, the piston will have
50 pounds pressure on every square inch of its surface, equal to 5,000
pounds.

THE PRESSURE OR HEAD.--In addition to that there will also be 50 pounds
pressure on each square inch of the head, as well as on the sides of the
cylinder.

Fig. 131 shows a cylinder (A), a piston (B) and a steam inlet port (C),
in which is indicated how the steam pressure acts equally in all
directions. As, however, the piston is the only movable part, the force
of the steam is directed to that part, and the motion is then
transmitted to the crank, and to the shaft of the engine.

[Illustration: _Fig. 131. Steam Pressure_]

[Illustration: _Fig. 132. Water Pressure_]

This same thing applies to water which, as stated, is dependent on its
head. Fig. 132 represents a cylinder (D) with a vertically movable
piston (E) and a standpipe (F). Assuming that the pipe (F) is of
sufficient height to give a pressure of 50 pounds to the square inch,
then the piston (E) and the sides and head of the cylinder (D) would
have 50 pounds pressure on every square inch of surface.

FUELS.--In the use of fuels, such as the volatile hydrocarbons, the
direct expansive power of the fuel gases developed, is used to move the
piston back and forth. Engines so driven are called _Internal Combustion
Motors_.

POWER FROM WINDS.--Another source of power is from the wind acting
against wheels which have blades or vanes disposed at such angles that
there is a direct conversion of a rectilinear force into circular
motion.

In this case power is derived from the force of the moving air and the
calculation of energy developed is made by considering the pressure on
each square foot of surface. The following table shows the force exerted
at different speeds against a flat surface one foot square, held so that
the wind strikes it squarely:

--------------------------------------------------------------------
-----------------+--------------++-------------------+--------------
SPEED OF WIND    |   PRESSURE   || SPEED OF WIND     |   PRESSURE
-----------------+--------------++-------------------+--------------
5 Miles per hour |        2 oz. || 35 miles per hour |  6 lb. 2 oz.
10 "        "    |        8  "  || 40   "       "    |  8  "
15 "        "    |  1 lb. 2  "  || 45   "       "    | 10  "  2  "
20 "        "    |  2  "        || 50   "       "    | 12  "  2  "
25 "        "    |  3  "  2  "  || 55   "       "    | 15  "  2  "
30 "        "    |  4  "  8  "  || 60   "       "    | 18  "
-----------------+--------------++-------------------+--------------

VARYING DEGREES OF PRESSURE.--It is curious to notice how the increase
in speed changes the pressure against the blade. Thus, a wind blowing 20
miles an hour shows 2 pounds pressure; whereas a wind twice that
velocity, or 40 miles an hour, shows a pressure of 8 pounds, which is
four times greater than at 20 miles.

It differs, therefore, from the law with respect to water pressure,
which is constant in relation to the height or the head--that is, for
every 28 inches height of water a pound pressure is added.

POWER FROM WAVES AND TIDES.--Many attempts have been made to harness the
waves and the tide and some of them have been successful. This effort
has been directed to the work of converting the oscillations of the
waves into a rotary motion, and also to take advantage of the to-and-fro
movement of the tidal flow. There is a great field in this direction for
the ingenious boy.

A PROFITABLE FIELD.--In no direction of human enterprise is there such
a wide and profitable field for work, as in the generation of power. It
is constantly growing in prominence, and calls for the exercise of the
skill of the engineer and the ingenuity of the mechanic. Efficiency and
economy are the two great watchwords, and this is what the world is
striving for. Success will come to him who can contribute to it in the
smallest degree.

Capital is not looking for men who can cheapen the production of an
article 50 per cent., but 1 per cent. The commercial world does not
expect an article to be 100 per cent, better. Five per cent. would be an
inducement for business.




CHAPTER XII

ON MEASURES


HORSE-POWER.--When work is performed it is designated as horse-power,
usually indicated by the letters H. P.; but the unit of work is called a
_foot pound_.

If one pound should be lifted 550 feet in one second, or 550 pounds one
foot in the same time, it would be designated as one horse-power. For
that reason it is called a foot pound. Instead of using the figure to
indicate the power exerted during one minute of time, the time is taken
for a minute, in all calculations, so that 550 multiplied by the number
of seconds, 60, in a minute, equals 33,000 foot pounds.

FOOT POUNDS.--The calculation of horse-power is in a large measure
arbitrary. It was determined in this way: Experiments show that the heat
expended in vaporizing 34 pounds of water per hour, develops a force
equal to 33,000 foot pounds; and since it takes about 4 pounds of coal
per hour to vaporize that amount of water, the heat developed by that
quantity of coal develops the same force as that exercised by an average
horse exerting his strength at ordinary work.

All power is expressed in foot pounds. Suppose a cannon ball of
sufficient weight and speed strikes an object. If the impact should
indicate 33,000 pounds it would not mean that the force employed was one
horse-power, but that many foot pounds.

If there should be 60 impacts of 550 pounds each within a minute, it
might be said that it would be equal to 1 horse-power, but the correct
way to express it would be foot pounds.

So in every calculation, where power is to be calculated, first find out
how many foot pounds are developed, and then use the unit of measure,
33,000, as the divisor to get the horse-power, if you wish to express it
in that way.

It must be understood, therefore, that horse-power is a simple unit of
work, whereas a foot pound is a compound unit formed of a foot paired
with the weight of a pound.

ENERGY.--Now _work_ and _energy_ are two different things. Work is the
overcoming of resistance of any kind, either by causing or changing
motion, or maintaining it against the action of some other force.

Energy, on the other hand, is the power of doing work. Falling water
possesses energy; so does a stone poised on the edge of a cliff. In the
case of water, it is called _kinetic_ energy; in the stone _potential_
energy. A pound of pressure against the stone will cause the latter, in
falling, to develop an enormous energy; so it will be seen that this
property resides, or is within the thing itself. It will be well to
remember these definitions.

HOW TO FIND OUT THE POWER DEVELOPED.--The measure of power produced by
an engine, or other source, is so interesting to boys that a sketch is
given of a Prony Brake, which is the simplest form of the Dynamometer,
as these measuring machines are called.

[Illustration: _Fig. 133. Prony Brake_]

In the drawing (A) is the shaft, with a pulley (A´), which turns in the
direction of the arrow (B). C is a lever which may be of any length.
This has a block (C´), which fits on the pulley, and below the shaft,
and surrounding it, are blocks (D) held against the pulley by a chain
(E), the ends of the chain being attached to bolts (F) which pass
through the block (C´) and lever (C).

Nuts (G) serve to draw the bolts upwardly and thus tighten the blocks
against the shaft. The free end of the lever has stops (H) above and
below, so as to limit its movement. Weights (I) are suspended from the
end of the lever.

[Illustration: _Fig. 134. Speed Indicator_]

THE TEST.--The test is made as follows: The shaft is set in motion, and
the nuts are tightened until its full power at the required speed is
balanced by the weight put on the platform.

The following calculation can then be made:

For our present purpose we shall assume that the diameter of the pulley
(A´) is 4 inches; the length of the lever (C), 3 feet; the speed of the
shaft (A) and the pulley, 210 revolutions per minute; and the weight 600
pounds.

Now proceed as follows:

(1) Multiply the diameter of the pulley (A´) (4 inches) by 3.1416, and
this will give the circumference 12.5664 inches; or, 1.0472 feet.

(2) Multiply this product (1.0472) by the revolutions per minute. 1.0472
× 210 = 219.912. This equals the _speed_ of the periphery of the pulley.

(3) The next step is to get the length of the lever (C) from the center
of the shaft (A) to the point from which the weights are suspended, and
divide this by one-half of the diameter of the pulley (A´). 36" ÷ 2" =
18", or 1-1/2 feet. This is the _leverage_.

(4) Then multiply the _weight_ in pounds by the _leverage_. 600 × 1-1/2
= 900.

(5) Next multiply this product (900) by the _speed_, 900 × 219.912 =
197,920.8, which means _foot pounds_.

(6) As each horse-power has 33,000 foot pounds, the last product should
be divided by this figure, and we have 197,920.8 ÷ 33,000 = 5.99 H. P.

THE FOOT MEASURE.--How long is a foot, and what is it determined by? It
is an arbitrary measure. The human foot is the basis of the measurement.
But what is the length of a man's foot? It varied in different countries
from 9 to 21 inches.

In England, in early days, it was defined as a measure of length
consisting of 12 inches, or 36 barleycorns laid end to end. But
barleycorns differ in length as well as the human foot, so the standard
adopted is without any real foundation or reason.

WEIGHT.--To determine weight, however, a scientific standard was
adopted. A gallon contains 8.33 pounds avoirdupois weight of distilled
water. This gallon is divided up in two ways; one by weight, and the
other by measurement.

Each gallon contains 231 cubic inches of distilled water. As it has four
quarts, each quart has 57-3/4 cubic inches, and as each quart is
comprised of two pints, each pint has nearly 29 cubic inches.

THE GALLON.--The legal gallon in the United States is equal to a
cylindrical measure 7 inches in diameter and 6 inches deep.

Notwithstanding the weights and dimensions of solids and liquids are
thus fixed by following a scientific standard, the divisions into
scruples, grains, pennyweights and tons, as well as cutting them up into
pints, quarts and other units, is done without any system, and for this
reason the need of a uniform method has been long considered by every
country.

THE METRIC SYSTEM.--As early as 1528, Fernal, a French physician,
suggested the metric system. Our own government recognized the value of
this plan when it established the system of coinage.

The principle lies in fixing a unit, such as a dollar, or a pound, or a
foot, and then making all divisions, or addition, in multiples of ten.
Thus, we have one mill; ten mills to make a dime; ten dimes to make a
dollar, and so on.

BASIS OF MEASUREMENT.--The question arose, what to use as the basis of
measurement, and it was proposed to use the earth itself, as the
measure. For this purpose the meridian line running around the earth at
the latitude of Paris was selected.

One-quarter of this measurement around the globe was found to be
393,707,900 inches, and this was divided into 10,000,000 parts. Each
part, therefore, was a little over 39.37 inches in length, and this was
called a meter, which means _measure_.

A decimeter is one-tenth of that, namely, 3.937 inches; and a decameter
39.37, or ten times the meter, and so on.

For convenience the metrical table is given, showing lengths in feet and
inches, in which only three decimal points are used.

Metrical Table, showing measurements in feet and inches:

METRICAL TABLE, SHOWING MEASUREMENTS IN FEET
AND INCHES

------------------------------------------
------------+--------------+--------------
   Length   |    Inches    |    Feet
------------+--------------+--------------
Millimeter  |       0.039  |      0.003
Centimeter  |       0.393  |      0.032
Decimeter   |       3.937  |      0.328
Meter       |      39.370  |      3.280
Decameter   |     393.707  |     32.808
Hectometer  |    3937.079  |    328.089
Kilometer   |   39370.790  |   3280.899
Myriameter  |  393707.900  |  32808.992
------------+--------------+--------------

METRIC SYSTEM, SHOWING THE EQUIVALENTS
IN OUR MEASURES

1 Myriameter            = 5.4 nautical miles, or 6.21 statute
                            miles.

1 Kilometer             = 0.621 statute mile, or nearly 5/8
                            mile.

1 Hectometer            = 109.4 yards.

1 Decameter             = 0.497 chain, 1.988 rods.

1 Meter                 = 39.37 inches, or nearly 3 ft. 3-3/8
                            inches.

1 Decimeter             = 3.937 inches.

1 Centimeter            = 0.3937 inch.

1 Millimeter            = 0.03937 inch.

1 Micron                = 1/25400 inch.

1 Hectare               = 2.471 acres.

1 Arc                   = 119.6 square yards.

1 Centaire, or square
meter                   = 10.764 square feet.

1 Decastere             = 13 cubic yards, or about 2-3/4
                            cords.

1 Stere, or cubic meter = 1.308 cubic yards, or 35.3 cubic
                            feet.

1 Decistere             = 3-1/2 cubic feet.

1 Kiloliter             = 1 ton, 12 gal., 2 pints, 2 gills
                            old wine measure.

1 Hectoliter            = 22.01 Imperial gals., or 26.4
                            U. S. gals.

1 Decaliter             = 2 gallons, 1 pint, 2-2/5 gills, imperial
                            measure, or 2 gals., 2
                            qts., 1 pt., 1/2 gill, U. S.

1 Liter                 = 1 pint, 3 gills, imperial, or 1 qt.,
                            1/2 gill U. S. measure.

1 Decileter             = 0.704 gill, imperial, or 0.845 gill
                            U. S. measure.

1 Millier               = 2,204.6 pounds avoirdupois.

1 Metric quintal        = 2  hundredweight, less 3-1/2
                            pounds, or 220 pounds, 7
                            ounces.

1 Kilogram              = 2  pounds, 3 ounces, 4-3/8
                            drams avoirdupois.

1 Hectogram             = 3 ounces, 8-3/8 drams avoirdupois.

1 Decagram              = 154.32 grains Troy.

1 Gram                  = 15.432 grains.

1 Decigram              = 1.542 grain.

1 Centigram             = 0.154 grain.

1 Milligram             = 0.015 grain.




CHAPTER XIII

USEFUL INFORMATION FOR THE WORKSHOP


To find the circumference of a circle: Multiply the diameter by 3.1416.

To find the diameter of a circle: Multiply the circle by .31831.

To find the area of a circle: Multiply the square of the diameter by
.7854.

To find the area of a triangle: Multiply the base by one-half the
perpendicular height.

To find the surface of a ball: Multiply the square of the diameter by
3.1416.

To find the solidity of a sphere: Multiply the cube of the diameter by
.5236.

To find the cubic contents of a cone: Multiply the area of the base by
one-third the altitude.

Doubling the diameter of a pipe increases its capacity four times.

To find the pressure in pounds per square inch of a column of water:
Multiply the height of the column in feet by .434.

Standard Horse-power: The evaporation of 30 pounds of water per hour
from a feed water temperature of 1,000 degrees Fahrenheit into steam at
70 pounds gauge pressure.

To find the capacity of any tank in gallons: Square the diameter in
inches, multiply by the length, and then by .0034.

In making patterns for aluminum castings provision must be made for
shrinkage to a greater extent than with any other metal or alloy.

The toughness of aluminum can be increased by adding a small per cent.
of phosphorus.

All alloys of metals having mercury are called _amalgams_.

A sheet of zinc suspended in the water of a boiler will produce an
electrolytic action and prevent scaling to a considerable extent.

Hydrofluoric acid will not affect a pure diamond, but will dissolve all
imitations.

A strong solution of alum put into glue will make it insoluble in water.

A grindstone with one side harder than the other can have its flinty
side softened by immersing that part in boiled linseed oil.

One barrel contains 3-3/4 cubic feet.

One cubic yard contains 7-1/4 barrels.

To find the speed of a driven pulley of a given diameter: Multiply the
diameter of the driving pulley by its speed or number of revolutions.
Divide this by the diameter of the driven pulley. The result will be the
number of revolutions of the driven pulley.

To find the diameter of a driven pulley that shall make any given number
of revolutions in the same time: Multiply the diameter of the driving
pulley by its number of revolutions, and divide the product by the
number of revolutions of the driven pulley.

A piece of the well-known tar soap held against the inside of a belt
while running will prevent it from slipping, and will not injure the
belt.

Boiler scale is composed of the carbonate or the sulphate of lime. To
prevent the formation it is necessary to use some substance which will
precipitate these elements in the water. The cheapest and most
universally used for this purpose are soda ash and caustic soda.

Gold bronze is merely a mixture of equal parts of oxide of tin and
sulphur. To unite them they are heated for some time in an earthen
retort.

Rusted utensils may be cleaned of rust by applying either turpentine or
kerosene oil, and allowing them to stand over night, when the excess may
be wiped off. Clean afterwards with fine emery cloth.

Plaster of paris is valuable for many purposes in a machine shop, but
the disadvantage in handling it is, that it sets so quickly, and its use
is, therefore, very much limited. To prevent quick setting mix a small
amount of arrow root powder with the plaster before it is mixed, and
this will keep it soft for some time, and also increase its hardness
when it sets.

For measuring purposes a tablespoon holds 1/2 ounce; a dessertspoon 1/4
ounce; a teaspoon 1/8 ounce; a teacupful of sugar weighs 1/2 pound; two
teacupsful of butter weigh 1 pound; 1-1/3 pints of powdered sugar weigh
1 pound; one pint of distilled water weighs 1 pound.

Ordinarily, 450 drops of liquid are equal to 1 ounce; this varies with
different liquids, some being thicker in consistency than others, but
for those of the consistency of water the measure given is fairly
accurate.




CHAPTER XIV

THE SIMPLICITY OF GREAT INVENTIONS, AND OF NATURE'S MANIFESTATIONS


If there is anything in the realm of mechanics which excites the wonder
and admiration of man, it is the knowledge that the greatest inventions
are the simplest, and that the inventor must take advantage of one law
in nature which is universal in its application, and that is vibration.

There is a key to every secret in nature's great storehouse. It is not a
complicated one, containing a multiplicity of wards and peculiar angles
and recesses. It is the very simplicity in most of the problems which
long served as a bar to discovery in many of the arts. So extremely
simple have been some of the keys that many inventions resulted from
accidents.

INVENTION PRECEDES SCIENCE.--Occasionally inventions were brought about
by persistency and energy, and ofttimes by theorizing; but science
rarely ever aids invention. The latter usually precedes science. Thus,
reasoning could not show how it might be possible for steam to force
water into a boiler against its own pressure. But the injector does
this.

If, prior to 1876, it had been suggested that a sonorous vibration could
be converted into an electrical pulsation, and transformed back again to
a sonorous vibration, science would have proclaimed it impossible; but
the telephone does it. Invention shows how things are done, and science
afterwards explains the phenomena and formulates theories and laws which
become serviceable to others in the arts.

SIMPLICITY IN INVENTIONS.--But let us see how exceedingly simple are
some of the great discoveries of man.

THE TELEGRAPH.--The telegraph is nothing but a magnet at each end of a
wire, with a lever for an armature, which opens and closes the circuit
that passes through the magnets and armature, so that an impulse on the
lever, or armature, at one end, by making and breaking the circuit, also
makes and breaks the circuit at the other end.

TELEPHONE.--The telephone has merely a disk close to but not touching
the end of a magnet. The sonorous vibration of the voice oscillates the
diaphragm, and as the diaphragm is in the magnetic field of the magnet,
it varies the pressure, so called, causing the diaphragm at the other
end of the wire to vibrate in unison and give out the same sound
originally imparted to the other diaphragm.

TRANSMITTER.--The transmitter is merely a sensitized instrument. It
depends solely on the principle of light contact points in an electric
circuit, whereby the vibrations of the voice are augmented.

PHONOGRAPH.--The phonograph is not an electrical instrument. It has a
diaphragm provided centrally with a blunt pin, or stylus. To make the
record, some soft or plastic material, like wax, or tinfoil, is caused
to move along so that the point of the stylus makes impressions in it,
and the vibrations of the diaphragm cause the point to traverse a groove
of greater or smaller indentations. When this groove is again presented
to the stylus the diaphragm is vibrated and gives forth the sounds
originally imparted to it when the indentations were made.

WIRELESS TELEGRAPHY.--Wireless telegraphy depends for its action on what
is called induction. Through this property a current is made of a high
electro-motive force, which means of a high voltage, and this disturbs
the ether with such intensity that the waves are sent out in all
directions to immense distances.

The great discovery has been to find a mechanism sensitive enough to
detect the induction waves. The instrument for this purpose is called a
coherer, in which small particles cohere through the action of the
electric waves, and are caused to fall apart mechanically, during the
electrical impulses.

PRINTING TELEGRAPH.--The printing telegraph requires the synchronous
turning of two wheels. This means that two wheels at opposite ends of a
wire must be made to turn at exactly the same rate of speed. Originally,
this was tried by clock work, but without success commercially, for the
reason that a pendulum does not beat with the same speed at the equator,
as at different latitudes, nor at altitudes; and temperature also
affects the rate. The solution was found by making the two wheels move
by means of a timing fork, which vibrates with the same speed
everywhere, and under all conditions.

ELECTRIC MOTOR.--The direct current electric motor depends for its
action on the principle that likes repel, and unlikes attract. The
commutator so arranges the poles that at the proper points, in the
revolution of the armature, the poles are always presented to each other
in such a way that as they approach each other, they are opposites, and
thus attract, and as they recede from each other they repel. A dynamo is
exactly the same, except that the commutator reverses the operation and
makes the poles alike as they approach each other, and unlike as they
recede.

Steel is simply iron, to which has been added a small per cent of
carbon.

Quinine is efficient in its natural state, but it has been made
infinitely more effectual by the breaking up or changing of the
molecules with acids. Sulphate of quinine is made by the use of
sulphuric acid as a solvent.

EXPLOSIONS.--Explosions depend on oxygen. While this element does not
burn, a certain amount of it must be present to support combustion.
Thus, the most inflammable gas or liquid will not burn or explode unless
oxygenized. Explosives are made by using a sufficient amount, in a
concentrated form, which is added to the fuel, so that when it is
ignited there is a sufficient amount of oxygen present to support
combustion, hence the rapid explosion which follows.

VIBRATION IN NATURE.--The physical meaning of vibration is best
illustrated by the movement of a pendulum. All agitation is vibration.
All force manifests itself in this way.

The painful brilliancy of the sun is produced by the rapid vibrations of
the rays; the twinkle of the distant star, the waves of the ocean when
ruffled by the winds; the shimmer of the moon on its crested surface;
the brain in thinking; the mouth in talking; the beating of the heart;
all, alike, obey the one grand and universal law of vibratory motion.

QUALITIES OF SOUND.--Sound is nothing but a succession of vibrations of
greater or less magnitude. Pitch is produced by the number of
vibrations; intensity by their force; and quality by the character of
the article vibrated.

Since the great telephone controversy which took place some years ago
there has been a wonderful development in the knowledge of acoustics, or
sounds. It was shown that the slightest sound would immediately set into
vibration every article of furniture in a room, and very sensitive
instruments have been devised to register the force and quality.

THE PHOTOGRAPHER'S PLATE.--It is known that the chemical action of an
object on a photographer's plate is due to vibration; each represents a
force of different intensity, hence the varying shades produced. Owing
to the different rates of vibrations caused by the different colors, the
difficulty has been to photograph them, but this has now been
accomplished. Harmony, or "being in tune," as is the common expression,
is as necessary in light, as in music.

Some chemicals will bring out or "develop," the pictures; others will
not. Colors are now photographed because invention and science have
found the harmonizing chemicals.

QUADRUPLEX TELEGRAPHY.--One of the most remarkable of all the wonders of
our age is what is known as duplex and quadruplex telegraphy. Every atom
and impulse in electricity is oscillation. The current which transmits
a telegram is designated in the science as "vibratory."

But how is it possible to transmit two or more messages over one wire at
the same time? It is by bringing into play the harmony of sounds. One
message is sent in one direction in the key of A; another message in the
other direction in B; and so any number may be sent, because the
electrical vibrations may be tuned, just like the strings of a violin.

ELECTRIC HARMONY.--Every sound produces a corresponding vibration in
surrounding objects. While each vibrates, or is capable of transmitting
a sound given to it by its vibratory powers, it may not vibrate in
harmony.

When a certain key of a piano is struck every key has a certain
vibration, and if we could separate it from the other sounds, it would
reflect the same sound as the string struck, just the same as the walls
of a room or the air itself would convey that sound.

But as no two strings in the instrument vibrate the same number of times
each second, the rapid movement of successive sounds of the keys do not
interfere with each other. If, however, there are several pianos in a
room, and all are tuned the same pitch, the striking of a key on one
instrument will instantly set in vibration the corresponding strings in
all the other instruments.

This is one reason why a piano tested in a music wareroom has always a
more beautiful and richer sound than when in a drawing-room or hall,
since each string is vibrated by the other instrument.

If a small piece of paper is balanced upon the strings of a violin,
every key of the piano may be struck, except the one in tune, without
affecting the paper; but the moment the same key is struck the vibration
of the harmonizing pitch will unbalance the paper.

The musical sound of C produces 528 vibrations per second; D 616, and so
on. The octave above has double the number of vibrations of the lower
note. It will thus be understood why discord in music is not pleasant to
the ear, as the vibrations are not in the proper multiples.

ODORS.--So with odors. The sense of smell is merely the force set in
motion by the vibration of the elements. An instrument called the
_odophone_ demonstrates that a scale or gamut exists in flowers; that
sharp smells indicate high tones and heavy smells low tones. Over fifty
odors have thus been analyzed.

The treble clef, note E, 4th space, is orange; note D, 1st space below,
violet; note F, 4th space above clef, ambergris. To make a proper
bouquet, therefore the different odors must be harmonized, just the
same as the notes of a musical chord are selected.

A BOUQUET OF VIBRATIONS.--The odophone shows that santal, geranium,
orange flower and camphor, make a bouquet in the key of C. It is easy to
conceive that a beautiful bouquet means nothing more than an agreeable
vibratory sensation of the olfactory nerves.

TASTE.--So with the sense of taste. The tongue is covered with minute
cells surrounded by nervous filaments which are set in motion whenever
any substance is brought into contact with the surface. Tasting is
merely the movement of these filaments, of greater or less rapidity.

If an article is tasteless, it means that these filaments do not
vibrate. These vibrations are of two kinds. They may move faster or
slower, or they may move in a peculiar way. A sharp acute taste means
that the vibrations are very rapid; a mild taste, slow vibrations.

When a pleasant taste is detected, it is only because the filaments are
set into an agreeable motion. The vibrations in the tongue may become so
rapid that it will be painful, just as a shriek becomes piercing to the
ear, or an intense light dazzling to the eye; all proceed from the same
physical force acting on the brain.

COLOR.--Color, that seemingly unexplainable force, becomes a simple
thing when the principles of vibration are applied, and this has been
fully explained by the spectroscope and its operation.

When the boy once appreciates that this force, or this motion in nature
is just as simple as the great inventions which have grown out of this
manifestation, he will understand that a knowledge of these things will
enable him to utilize the energy in a proper way.




CHAPTER XV

WORKSHOP RECIPES AND FORMULAS


In a work of this kind, dealing with the various elements, the boy
should have at hand recipes or formulas for everything which comes
within the province of his experiments. The following are most carefully
selected, the objects being to present those which are the more easily
compounded.

ADHESIVES FOR VARIOUS USES.--Waterproof glue. Use a good quality of
glue, and dissolve it in warm water, then add one pound of linseed oil
to eight pounds of the glue. Add three ounces of nitric acid.

Leather or Card-board Glue. After dissolving good glue in water, to
which a little turpentine has been added, mix it with a thick paste of
starch, the proportion of starch to glue being about two to every part
of glue used. The mixture is used cold.

A fine Belt Glue. Dissolve 50 ounces of gelatine in water, and heat
after pouring off the excess water. Then stir in five ounces of
glycerine, ten ounces of turpentine, and five ounces of linseed oil
varnish. If too thick add water to suit.

For cementing Iron to Marble. Use 30 parts of Plaster of Paris, 10 parts
of iron filings, and one half part of sal ammoniac. These are mixed up
with vinegar to make a fluid paste.

To cement Glass to Iron. Use 3 ounces of boiled linseed oil and 1 part
of copal varnish, and into this put 2 ounces of litharge and 1 ounce of
white lead and thoroughly mingle so as to make a smooth paste.

Water-proof Cement. Boiled linseed oil, 6 ounces; copal, 6 ounces;
litharge, 2 ounces; and white lead, 16 ounces. To be thoroughly
incorporated.

To unite rubber or leather to hard substances. One ounce of pulverized
gum shellac dissolved in 9-1/2 ounces of strong ammonia, will make an
elastic cement. Must be kept tightly corked.

For uniting iron to iron. Use equal parts of boiled oil, white lead,
pipe clay and black oxide of manganese, and form it into a paste.

Transparent Cement. Unite 1 ounce of india rubber, 67 ounces of
chloroform, and 40 ounces of mastic. This is to be kept together for a
week, and stirred at times, when it will be ready for use.

To Attach Cloth to Metal. Water 100 parts, sugar 10 parts, starch 20
parts, and zinc chloride 1 part. This must be first stirred and made
free of lumps, and then heated until it thickens.

United States Government Gum. Dissolve 1 part of gum arabic in water and
add 4 parts of sugar and 1 part of starch. This is then boiled for a
few minutes, and thinned down as required.

TO MAKE DIFFERENT ALLOYS.--Silver-aluminum. Silver one-fourth part, and
aluminum three-fourth parts.

Bell-metal. Copper, 80 parts; tin, 20 parts. Or, copper, 72 parts; tin,
26 parts; zinc, 2 parts. Or, copper 2; 1 of tin.

Brass. Copper, 66 parts; zinc, 32 parts; tin, 1 part; lead, 1 part.

Bronzes. Copper, 65 parts; zinc, 30 parts; tin, 5 parts. Or, copper, 85
parts; zinc, 10 parts; tin, 3 parts; lead, 2 parts.

German Silver. 52 parts of copper; 26 parts zinc; 22 parts nickel.

For Coating Mirrors. Tin, 70 parts; mercury, 30 parts.

BOILER COMPOUNDS.--To prevent scaling. Use common washing soda, or
Glauber salts.

TO DISSOLVE CELLULOID.--Use 50 parts of alcohol and 5 parts of camphor
for every 5 parts of celluloid. When the celluloid is put into the
solution it will dissolve it.

To Soften Celluloid. This may be done by simply heating, so it will
bend, and by putting it in steam, it can be worked like dough.

CLAY MIXTURE FOR FORGES.--Mix dry 20 parts of fire clay, 20 parts
cast-iron turnings, one part of common salt, and 1/2 part sal ammoniac,
and then add water while stirring, so as to form a mortar of the proper
consistency. The mixture will become very hard when heat is applied.

A Modeling Clay. This is made by mixing the clay with glycerine and
afterwards adding vaseline. If too much vaseline is added it becomes too
soft.

FLUIDS FOR CLEANING CLOTHES, FURNITURE, ETC.--For Delicate Fabrics. Make
strong decoction of soap bark, and put into alcohol.

Non-inflammable Cleaner. Equal parts of acetone, ammonia and diluted
alcohol.

Taking dried paint from clothing. Shake up 2 parts of ammonia water with
1 part of spirits of turpentine.

Cleaning Furniture, etc. Unite 2.4 parts of wax; 9.4 parts of oil of
turpentine; 42 parts acetic acid; 42 parts citric acid; 42 parts white
soap. This must be well mingled before using.

Removing Rust from Iron or Steel. Rub the surface with oil of tartar.
Or, apply turpentine or kerosene, and after allowing to stand over
night, clean with emery cloth.

For Removing Ink Stains from Silver. Use a paste made of chloride of
lime and water.

To clean Silver-Plated Ware. Make a mixture of cream of tartar, 2 parts;
levigated chalk, 2 parts; and alum, 1 part. Grind up the alum and mix
thoroughly.

Cleaning a Gas Stove. Make a solution of 9 parts of caustic soda and 150
parts of water, and put the separate parts of the stove in the solution
for an hour or two. The parts will come out looking like new.

Cleaning Aluminum. A few drops of sulphuric acid in water will restore
the luster to aluminum ware.

Oil Eradicator. Soap spirits, 100 parts; ammonia solution, 25; acetic
ether, 15 parts.

DISINFECTANTS.--Camphor, 1 ounce; carbolic acid (75 per cent.), 12
ounces; aqua ammonia, 10 drachms; soft salt water, 8 drachms.

Water-Closet Deodorant. Ferric chloride, 4 parts; zinc chloride, 5
parts; aluminum chloride, 4 parts; calcium chloride, 5 parts; magnesium
chloride, 3 parts; and water sufficient to make 90 parts. When all is
dissolved add to each gallon 10 grains of thymol and a quarter-ounce of
rosemary that had been previously dissolved in six quarts of alcohol.

Odorless Disinfectants. Mercuric chloride, 1 part; cupric sulphate, 10
parts; zinc sulphate, 50 parts; sodium chloride, 65 parts; water to make
1,000 parts.

Emery for Lapping Purposes. Fill a pint bottle with machine oil and
emery flour, in the proportion of 7 parts oil and 1 part emery. Allow it
to stand for twenty minutes, after shaking up well, then pour off half
the contents, without disturbing the settlings, and the part so poured
off contains only the finest of the emery particles, and is the only
part which should be used on the lapping roller.

EXPLOSIVES.--Common Gunpowder. Potassium nitrate, 75 parts; charcoal, 15
parts; sulphur, 10 parts.

Dynamite. 75 per cent. nitro-glycerine; 25 per cent. infusorial earth.

Giant Powder. 36 per cent. nitro-glycerine; 48 per cent. nitrate of
potash; 8 per cent. of sulphur; 8 per cent. charcoal.

Fulminate. Chlorate of potassia, 6 parts; pure lampblack, 4 parts;
sulphur, 1 part. A blow will cause it to explode.

FILES.--How to Keep Clean. Olive oil is the proper substance to rub over
files, as this will prevent the creases from filling up while in use,
and preserve the file for a longer time, and also enable it to do better
cutting.

To Renew Old Files. Use a potash bath for boiling them in, and
afterwards brush them well so as to get the creases clean. Then stretch
a cotton cloth between two supports, and after plunging the file into
nitric acid, use the stretched cloth to wipe off the acid. The object is
to remove the acid from the ridges of the file, so the acid will only
eat out or etch the deep portions between the ridges, and not affect the
edges or teeth.

FIRE PROOF MATERIALS OR SUBSTANCES.--For Wood. For the kind where it is
desired to apply with a brush, use 100 parts sodium silicate; 50 parts
of Spanish white, and 100 parts of glue. It must be applied hot.

Another good preparation is made as follows: Sodium silicate, 350 parts;
asbestos, powdered, 350 parts; and boiling water 1,000 parts.

For Coating Steel, etc. Silica, 50 parts; plastic fire clay, 10 parts;
ball clay, 3 parts. To be thoroughly mixed.

For Paper. Ammonium sulphate, 8 parts; boracic acid, 3 parts; borax, 2
parts; water, 100 parts. This is applied in a liquid state to the paper
surface.

FLOOR DRESSINGS.--Oil Stain. Neats' foot oil, 1 part; cottonseed oil, 1
part; petroleum oil, 1 part. This may be colored with anything desired,
like burnt sienna, annatto, or other coloring material.

Ballroom Powder. Hard paraffine, 1 pound; powdered boric acid, 7 pounds;
oil of lavender, 1 drachm; oil of neroli, 20 minims.

FOOT POWDERS.--For Perspiring Feet. Balsam Peru, 15 minims; formic
acid, 1 drachm; chloral hydrate, 1 drachm; alcohol to make 3 ounces.

For Easing Feet. Tannaform, 1 drachm; talcum, 2 drachms; lycopodium, 30
grains.

Frost Bites. Carbolized water, 4 drachms; nitric acid, 1 drop; oil of
geranium, 1 drop.

GLASS.--To cut glass, hold it under water, and use a pair of shears.

To make a hole through glass, place a circle of moist earth on the
glass, and form a hole in this the diameter wanted for the hole, and in
this hole pour molten lead, and the part touched by the lead will fall
out.

To Frost Glass. Cover it with a mixture of 6 ounces of magnesium
sulphate, 2 ounces of dextrine, and 20 ounces of water. This produces a
fine effect.

To imitate ground glass, use a composition of sandarac, 2-1/2 ounces;
mastic, 1/2 ounce; ether, 24 ounces; and benzine, 16 ounces.

IRON AND STEEL.--How to distinguish them. Wash the metal and put it into
a solution of bichromate of potash to which has been added a small
amount of sulphuric acid. In a minute or so take out the metal, wash and
wipe it. Soft steel and cast iron will have the appearance of an
ash-gray tint; tempered steels will be black; and puddled or refined
irons will be nearly white and have a metallic reflection.

To Harden Iron or Steel. If wrought iron, put in the charge 20 parts, by
weight, of common salt, 2 parts of potassium cyanide, .3 part of
potassium bichromate, .15 part of broken glass.

To harden cast iron, there should be added to the charge the following:
To 60 parts of water, add 2-1/2 parts of vinegar, 3 parts of common
salt, and .25 part of hydrochloric acid.

To soften castings: Heat them to a high temperature and cover them with
fine coal dust and allow to cool gradually.

LACQUERS.--For Aluminum. Dissolve 100 parts of gum lac in 300 parts of
ammonia and heat for an hour moderately in a water bath. The aluminum
must be well cleaned before applying. Heat the aluminum plate
afterwards.

For Brass. Make a compound as follows; Annatto, 1/4 ounce; saffro, 1/4
ounce; turmeric, 1 ounce; seed lac, 3 ounces; and alcohol, 1 pint. Allow
the mixture to stand for three days, then strain in the vessel which
contains the seed lac, and allow to stand until all is dissolved.

For Copper. Heat fine, thickly liquid amber varnish so it can be readily
applied to the copper, and this is allowed to dry. Then heat the coated
object until it commences to smoke and turn brown.

LUBRICANTS.--Heavy machinery oils. Use paraffine, 8 pounds; palm oil, 20
pounds; and oleonaptha, 12 pounds. Dissolve the paraffine in the
oleonaptha at a temperature of 160 degrees and then stir in the palm oil
a little at a time.

For Cutting Tools. Heat six gallons of water and put in three and a half
pounds of soft soap and a half gallon of clean refuse oil. It should be
well mixed.

For high-speed bearings. Use flaky graphite and kerosene oil. Apply this
as soon as there is any indication of heating in the bearings.

For lathe centers, one part of graphite and four parts of tallow
thoroughly mixed and applied will be very serviceable.

For Wooden Gears. Use tallow, 30 parts; palm oil; 20 parts; fish oil, 10
parts; and graphite, 20 parts.

PAPER.--FIRE PROOF PAPER.--Make the following solution: Ammonium
sulphate, 8 parts; boracic acid, 3 parts; water, 100 parts. Mix at a
temperature of 120 degrees. Paper coated with this will resist heat.

Filter Paper. Dip the paper into nitric acid of 1.433 specific gravity,
and subsequently wash and dry it. This makes a fine filtering body.

Carbon Paper. A variety of substances may be used, such as fine soot or
ivory black, ultramarine or Paris blue. Mix either with fine grain
soap, so it is of a uniform consistency and then apply to the paper with
a stiff brush, rubbing it in until it is evenly spread over the surface.

Tracing Paper. Take unsized paper and apply a coat of varnish made of
equal parts of Canada balsam and oil of turpentine. To increase the
transparency give another coat. The sheets must be well dried before
using.

PHOTOGRAPHY.--Developers.

1. Pure water, 30 ounces; sulphite soda, 5 ounces; carbonate soda, 2-1/2
ounces.

2. Pure water, 24 ounces; oxalic acid, 15 grains; pyrogallic acid, 1
ounce.

To develop use of solution 1, 1 ounce; solution 2, 1/2 ounce; and water,
3 ounces.

Stock solutions for developing: Make solution No. 1 as follows: water,
32 ounces; tolidol, I ounce; sodium sulphate, 1-1/2 ounces.

Solution No. 2: Water, 32 ounces; sodium sulphate.

Solution No. 3: Water, 32 ounces; sodium carbonate, from 4 to 6 ounces.

Fixing bath. Add two ounces of S. P. C. clarifier (acid bisulphate of
sodium) solution to one quart of hypo solution 1 in 5.

Clearing solution. Saturated solution of alum, 20 ounces; and
hydrochloric acid, 1 ounce. Varnish. Brush over the negative a solution
of equal parts of benzol and Japanese gold size.

PLASTERS.--Court Plaster. Use good quality silk, and on this spread a
solution of isinglass warmed. Dry and repeat several times, then apply
several coats of balsam of Peru. Or,

On muslin or silk properly stretched, apply a thin coating of smooth
strained flour paste, and when dry several coats of colorless gelatine
are added. The gelatine is applied warm, and cooled before the fabric is
taken off.

PLATING.--Bronze coating. For antiques, use vinegar, 1,000 parts; by
weight, powdered bloodstone, 125 parts; plumbago, 25 parts. Apply with
brush.

For brass where a copper surface is desired, make a rouge with a little
chloride of platinum and water, and apply with a brush.

For gas fixtures. Use a bronze paint and mix with it five times its
volume of spirit of turpentine, and to this mixture add dried slaked
lime, about 40 grains to the pint. Agitate well and decant the clear
liquid.

COLORING METALS.--Brilliant black for iron. Selenious acid, 6 parts;
cupric sulphate, 10 parts; water 1,000 parts; nitric acid, 5 parts.

Blue-black. Selenious acid, 10 parts; nitric acid, 5 parts; cupric
sulphate; water, 1,000 parts. The colors will be varied dependent on
the time the objects are immersed in the solution.

Brass may be colored brown by using an acid solution of nitrate of
silver and bismuth; or a light bronze by an acid solution of nitrate of
silver and copper; or black by a solution of nitrate of copper.

To copper plate aluminum, take 30 parts of sulphate of copper; 30 parts
of cream of tartar; 25 parts of soda; and 1,000 parts of water. The
article to be coated is merely dipped into the solution.

POLISHERS.--Floor Polish. Permanganate of potash in boiling water,
applied to the floor hot, will produce a stain, the color being
dependent on the number of coats. The floor may them be polished with
beeswax and turpentine.

For Furniture. Make a paste of equal parts of plaster of paris, whiting,
pumice stone and litharge, mixed with Japan dryer, boiled linseed oil
and turpentine. This may be colored to suit. This will fill the cracks
of the wood. Afterwards rub over the entire surface of the wood with a
mixture of 1 part Japan, 2 of linseed oil, and three parts of
turpentine, also colored, and after this has been allowed to slightly
harden, rub it off, and within a day or two it will have hardened
sufficiently so that the surface can be polished.

Stove Polish. Ceresine, 12 parts; Japan wax, 10 parts; turpentine oil,
100 parts; lampblack, 12 parts; graphite, 10 parts. Melt the ceresine
and wax together, and cool off partly, and then add and stir in the
graphite and lampblack which were previously mixed up with the
turpentine.

PUTTY.--Black Putty. Whiting and antimony sulphide, and soluble glass.
This can be polished finely after hardening.

Common Putty. Whiting and linseed oil mixed up to form a dough.

RUST PREVENTIVE.--For Machinery. Dissolve an ounce of camphor in one
pound of melted lard. Mix with this enough fine black lead to give it an
iron color. After it has been on for a day, rub off with a cloth.

For tools, yellow vaseline is the best substance.

For zinc, clean the plate by immersing in water that has a small amount
of sulphuric acid in it. Then wash clean and coat with asphalt varnish.

SOLDERS.--For aluminum. Use 5 parts of tin and 1 part of aluminum as the
alloy, and solder with the iron or a blow pipe.

Yellow hard solder. Brass, 3-1/2 parts; and zinc, 1 part.

For easily fusing, make an alloy of equal parts of brass and zinc.

For a white hard solder use brass, 12 parts; zinc, 1 part; and tin, 2
parts.

SOLDERING FLUXES.--For soft soldering, use a solution of chloride of
zinc and sal ammoniac. Powdered rosin is also used.

For hard soldering, borax is used most frequently.

A mixture of equal parts of cryolite and barium chloride is very good in
soldering bronze or aluminum alloys.

Other hard solders are alloyed as follows: brass, 4 parts; and zinc, 5
parts. Also brass, 7 parts; and zinc, 2 parts.

Steel Tempering-.-Heat the steel red hot and then plunge it into sealing
wax.

For tempering small steel springs, they may be plunged into a fish oil
which has a small amount of rosin and tallow.

VARNISHES.--Black Varnish. Shellac, 5 parts; borax, 2 parts; glycerine,
2 parts; aniline black, 6 parts; water, 45 parts. Dissolve the shellac
in hot water and add the other ingredients at a temperature of 200
degrees.

A good can varnish is made by dissolving 15 parts of shellac, and adding
thereto 2 parts of Venice turpentine, 8 parts of sandarac, and 75 parts
of spirits.

A varnish for tin and other small metal boxes is made of 75 parts
alcohol, which dissolves 15 parts of shellac, and 3 parts of turpentine.

SEALING WAX.--For modeling purposes. White wax, 20 parts; turpentine, 5
parts; sesame oil, 2 parts; vermilion, 2 parts.

Ordinary Sealing. 4 pounds of shellac, 1 pound Venice turpentine, add 3
pounds of vermilion. Unite by heat.




CHAPTER XVI

HANDY TABLES


TABLE OF WEIGHTS FOR ROUND AND SQUARE STEEL.

The Estimate is on the basis of Lineal Feet. 1 cu. ft. of Steel--490
lbs.

==========+===================+==========+===================
          |                   |          |
          | Weight in Pounds  |          | Weight in Pounds
 Sizes in |                   | Sizes in |
  Inches  +---------+---------+  Inches  +---------+---------
          |  Round  | Square  |          |  Round  | Square
----------+---------+---------+----------+---------+---------
   1/16   |   .110  |   .013  |  1-1/16  |  3.014  |  3.400
   1/8    |   .042  |   .053  |  1-1/8   |  3.379  |  3.838
   3/16   |   .094  |   .119  |  1-3/16  |  3.766  |  4.303
   1/4    |   .167  |   .212  |  1-1/4   |  4.173  |  4.795
   5/16   |   .261  |   .333  |  1-5/16  |  4.600  |  5.312
   3/8    |   .375  |   .478  |  1-3/8   |  5.049  |  5.857
   7/16   |   .511  |   .651  |  1-7/16  |  5.518  |  6.428
   1/2    |   .667  |   .850  |  1-1/2   |  6.008  |  7.650
   9/16   |   .845  |  1.026  |  1-9/16  |  6.520  |  7.650
   5/8    |  1.043  |  1.328  |  1-5/8   |  7.051  |  8.301
  11/16   |  1.262  |  1.608  |  1-11/16 |  7.604  |  8.978
   3/4    |  1.502  |  1.913  |  1-3/4   |  8.178  | 10.41
  13/16   |  1.773  |  2.245  |  1-13/16 |  8.773  | 11.17
   7/8    |  2.044  |  2.603  |  1-7/8   |  9.388  | 11.95
  15/16   |  2.347  |  2.989  |  1-15/16 | 10.02   | 12.76
    1     |  2.670  |  3.400  |  2       | 10.68   | 13.60
----------+---------+---------+----------+---------+---------

WEIGHT OF FLAT STEEL BARS.

=========+=============================================================
Thickness|
   in    |                             Width
 Inches  |
---------+------+------+------+------+------+------+-----+------+------
   1/16  |  .212|  .265|  .32 |  .372|  .425|  .477|  .53|  .588|  .63
   1/8   |  .425|  .53 |  .64 |  .745|  .85 |  .955| 1.06| 1.17 | 1.27
   3/16  |  .638|  .797|  .957| 1.11 | 1.28 | 1.44 | 1.59| 1.75 | 1.91
   1/4   |  .85 | 1.06 | 1.28 | 1.49 | 1.70 | 1.91 | 2.12| 2.34 | 2.55
   5/16  | 1.06 | 1.33 | 1.59 | 1.86 | 2.12 | 2.39 | 2.65| 2.92 | 3.19
   3/8   | 1.28 | 1.59 | 1.92 | 2.23 | 2.55 | 2.87 | 3.19| 3.51 | 3.83
   7/16  | 1.49 | 1.85 | 2.23 | 2.60 | 2.98 | 3.35 | 3.72| 4.09 | 4.46
   1/2   | 1.70 | 2.12 | 2.55 | 2.98 | 3.40 | 3.83 | 4.25| 4.67 | 5.10
   9/16  | 1.92 | 2.39 | 2.87 | 3.35 | 3.83 | 4.30 | 4.78| 5.26 | 5.74
   5/8   | 2.12 | 2.65 | 3.19 | 3.72 | 4.25 | 4.78 | 5.31| 5.84 | 6.38
  11/16  | 2.34 | 2.92 | 3.51 | 4.09 | 4.67 | 5.26 | 5.84| 6.43 | 7.02
   3/4   | 2.55 | 3.19 | 3.83 | 4.47 | 5.10 | 5.75 | 6.38| 7.02 | 7.65
  13/16  | 2.76 | 3.45 | 4.14 | 4.48 | 5.53 | 6.21 | 6.90| 7.60 | 8.29
   7/8   | 2.98 | 3.72 | 4.47 | 5.20 | 5.95 | 6.69 | 7.44| 8.18 | 8.93
  15/16  | 3.19 | 3.99 | 4.78 | 5.58 | 6.38 | 7.18 | 7.97| 8.77 | 9.57
    1    | 3.40 | 4.25 | 5.10 | 5.95 | 6.80 | 7.65 | 8.50| 9.35 |10.20
---------+------+------+------+------+------+------+-----+------+------

AVOIRDUPOIS WEIGHT.

For Merchandise of all kinds.

   16 Drams (dr.) make            1 Ounce (oz.)
   16 Ounces make                 1 Pound (pd.)
   25 Pounds make                 1 Quarter (qr.)
    4 Quarters, or 100 lbs., make 1 Hundredweight (cwt.)
   20 Hundredweights make         1 Ton (T.)
2,240 Pounds make                 1 Long ton (L. T.)


TROY WEIGHT.

For Gold, Silver, and Precious Metals.

24 Grains (gr.) make    1 Pennyweight (pwt.)
20 Pennyweights make    1 Ounce (oz.)
12 Ounces make          1 Pound (pd.)


APOTHECARIES WEIGHT.

For Drugs, Medicals and Chemicals.

20 Grains (gr.) make     1 Scruple (sc.)
 3 Scruples make         1 Dram (dr.)
 8 Drams make            1 Ounce (oz.)
12 Ounces make           1 Pound (pd.)

LINEAR MEASURE.

For Surveyors' Use.

12 Inches make         1 Foot
3 Feet make            1 Yard
5-1/2 Yards make       1 Rod
40 Rods make           1 Furlong
8 Furlongs             1 Mile


LONG MEASURE.

12 Inches make      1 Foot
3 Feet make         1 Yard
6 Feet make         1 Fathom
5-1/2 Yards make    1 Rod or pole
40 Poles make       1 Furlong
8 Furlongs make     1 Mile
3 Miles make        1 League
69-1/2 Miles make   1 Degree


SQUARE MEASURE.

144 square inches make      1 square foot
9 square feet make          1 square yard
30-1/2 square yards make    1 square pole
40 square poles make        1 square rod
4 square rods make          1 acre
640 square acres make       1 acre mile

SOLID OR CUBIC MEASURE.

1,728 Cubic inches make     1 Cubic foot
27 Cubic feet make          1 Cubic yard
128 Cubic feet make         1 Cord of wood
24-3/4 Cubic feet make      1 Perch of stone


DRY MEASURE.

2 Pints make        1 Quart (qt.)
8 Quarts make       1 peck (pk.)
4 Pecks make        1 Bushel (bu.)
36 Bushels make     1 Chaldron (ch.)


LIQUID MEASURE.

4 Gills (g.) make            1 Pint (pt.)
2 Pints make                 1 Quart (qt.)
4 Quarts make                1 Gallon (gal.)
31-1/2 Gallons make          1 Barrel (bbl.)
2 Bbls., or 63 gals., make.   1 Hogshead (hhd.)


PAPER MEASURE.

24 Sheets (sh.) make   1 Quire (qu.)
20 Quires make         1 Ream (r.)
10 Reams make          1 Bale (ba.) or bundle.

TABLE OF TEMPERATURES.

Greatest artificial cold   220   degrees below Fahr.
    "    natural      "     73.7    "      "      "
Mercury freezes             39      "      "      "
Mixture of snow and salt     4      "      "      "
Greatest density of water at 39.2   "    above    "
Blood Heat                   97.9   "      "      "
Alcohol boils               172.4   "      "      "
Water boils                 212     "      "      "
Mercury boils               662     "      "      "
Sulphur boils               824     "      "      "
Silver melts              1,749     "      "      "
Cast iron melts           2,786     "      "      "


STRENGTH OF VARIOUS METALS.

The tests are made by using a cubic inch of the metal and compressing
it, and by trying to draw apart a square inch of metal. Indicated in
pounds.

========================+=========+=============
                        | Tension | Compression
------------------------+---------+-------------
Aluminum                |  15,000 |   12,000
Brass, cast             |  24,000 |   30,000
Bronze, gun metal       |  32,000 |   20,000
  "     manganese       |  60,000 |  120,000
  "      phosphor       |  50,000 |   ......
Copper, cast            |  24,000 |   40,000
  "     wire annealed.  |  36,000 |   ......
  "       " unannealed  |  60,000 |   ......
Iron, cast              |  15,000 |   ......
  "     "  annealed     |  60,000 |   80,000
  "     "  unannealed   |  80,000 |   ......
  "   wrought           |  48,000 |   46,000
Lead, cast              |   2,000 |   ......
Steel castings          |  70,000 |   70,000
  "   plow              | 270,000 |   ......
  "   structural        |  60,000 |   60,000
  "   wire annealed     |  80,000 |   ......
  "   crucible          | 180,000 |   ......
Tin                     |   3,800 |    6,000
------------------------+---------+-------------

FREEZING MIXTURES

===============================================+=======================
                                               |Temperature Changes
                                               |in Degrees Fahrenheit
                                               +---------+------------
          Mixtures                             | From    |   To
-----------------------------------------------+---------+------------
Common salt, 1 part; snow, 3 parts             |   32    | zero .0
Common salt, 1 part; snow 1 part               |   32    |     -.4
Calcium chloride, 3 parts; snow 1 part         |   32    |     -27
Calcium chloride, 2 parts; snow 1 part         |   32    |     -44
Sal ammoniac, 5 parts; salt-peter 5 parts;     |         |
  water 16 parts.                              |   50    |     -10
Sal ammoniac, 1 part; salt-peter 1 part;       |         |
  water 1 part                                 |   46    |     -11
Ammonium nitrate, 1 part; water 1 part         |   50    |      -3
Potassium hydrate, 4 parts; snow 3 parts       |   32    |     -35
-----------------------------------------------+---------+------------

IGNITION TEMPERATURES.

Phosphorus                 120 degrees Fahrenheit
Bi-sulphide of carbon      300    "        "
Gun-cotton                 430    "        "
Nitro-glycerine            490    "        "
Phosphorus, amorphous      500    "        "
Rifle powder               550    "        "
Charcoal                   660    "        "
Dry pine wood              800    "        "
Oak                        900    "        "

POWER AND HEAT EQUIVALENTS.

In studying matters pertaining to power and heat, certain terms are
used, such as horsepower, horsepower-hours, watts, watt-hours, kilowatt,
kilowatt-hours, foot-pounds, joule, and B. T. U. (British Thermal Unit).

The following tables give a comprehensive idea of the values of the
different terms:

1 Horsepower-hour = 0.746 kilowatt-hour = 1,980,000 foot-pounds
                    of water evaporated at 212 degrees Fahrenheit,
                    raised from 62 degrees to 212 degrees.

1 Kilowatt-hour   = 1,000 watt-hours = 1.34 horse-power-hours
                    = 2,653,200 foot-pounds = 3,600,000 joules
                    = 3,420 B. T. U. = 3.54 pounds of water evaporated
                    at 212 degrees = 22.8 pounds of water raised from
                    62 to 212 degrees.

1 Horsepower      = 746 watts = 0.746 kilowatts.= 33,000 foot-pounds
                    per second = 2,550 B. T. U. per min. = 0.71
                    B. T. U. per second = 2.64 pounds of water
                    evaporated per hour at 212 degrees.

1 Kilowatt        = 1,000 watts = 1.34 horsepower = 2,653,200
                    foot-pounds per hour = 44,220 foot-pounds per
                    min. = 737 foot-pounds per second = 3,420
                    B. T. U. per hour = 57 B. T. U. per min. = 0.95
                    B. T. U. per second = 3.54 pounds of water
                    evaporated per hour at 212.

1 Watt            = 1 joule per second = 0.00134 horse-power = 0.001
                    kilowatt = 342 B. T. U. per hour = 44.22
                    foot-pounds per min. = 0.74 foot-pounds per second
                    = 0.0035 pounds of water evaporated per hour at
                    212 degrees.

1 B. T. U. (British Thermal Unit) = 1,052 watt-seconds = 778
                    foot-pounds = 0.252 calorie = 0.000292
                    kilowatt-hours = 0.000391 horsepower-hour
                    = 0.00104 pounds of water evaporated at 212
                    degrees.

1 Foot-pound      = 1.36 joule = 0.000000377 kilowatt-hour =
                    0.00129 B. T. U. = 0.0000005 horsepower-hour.

1 Joule           = 1 watt-second = 0.000000278 kilowatt-hour =
                    0.00095 B. T. U. = 0.74 foot-pounds.




CHAPTER XVII

INVENTIONS AND PATENTS, AND INFORMATION ABOUT THE RIGHTS AND DUTIES OF
INVENTORS AND WORKMEN


There is no trade or occupation which calls forth the inventive faculty
to a greater degree than the machinist's. Whether it be in the direction
of making some new tool, needed in some special work, or in devising a
particular movement, or mechanical expedient, the machinist must be
prepared to meet the issues and decide on the best structural
arrangement.

Opportunities also come daily to the workers in machine shops to a
greater extent than other artisans, because inventors in every line
bring inventions to them to be built and experimentally tested.

A knowledge of the rights and duties of inventors, and of the men who
build the models, is very desirable; and for your convenience we append
the following information:

The inventor of a device is he who has conceived an idea and has put it
into some concrete form.

A mere idea is not an invention.

The article so conceived and constructed, must be both _new_ and
_useful_. There must be some utility. It may be simply a toy, or
something to amuse.

If A has an idea, and he employs and pays B to work out the device, and
put it into practical shape, A is the inventor, although B may have
materially modified, or even wholly changed it. B is simply the agent or
tool to bring it to perfection, and his pay for doing the work is his
compensation.

An inventor has two years' time within which he may apply for a patent,
after he has completed his device and begun the sale of it. If he sells
the article for more than two years before applying for a patent, this
will bar a grant.

Two or more inventors may apply for a patent, provided each has
contributed something toward bringing it to its perfected state. Each
cannot apply separately. The patent issued will be owned by them
jointly.

Joint owners of a patent are not partners, unless they have signed
partnership papers respecting the patent. Because they are partners in
some other enterprise, disconnected from the patent, that does not
constitute them partners in the patent. They are merely joint owners.

If they have no special agreement with respect to the patent each can
grant licenses to manufacture, independently of the others, without
being compelled to account to the others, and each has a right to sell
his interest without asking permission of the others.

An _inventor_ is one who has devised an invention. A _patentee_ is one
who owns a patent, or an interest in one, be he the inventor or not.

The United States government does not grant Caveats. The only protection
offered is by way of patent.

A patent runs for a period of seventeen years, and may be renewed by act
of Congress only, for a further term of seven years.

An interference is a proceeding in the Patent Office to determine who is
the first inventor of a device. The following is a brief statement of
the course followed:

When two or more applicants have applications pending, which, in the
opinion of the Examiner, appear to be similar, the Office may declare an
interference.

If an applicant has an application pending, and the Examiner rejects it
on reference to a patent already issued, the applicant may demand an
interference, and the Office will then grant a hearing to determine
which of the two is entitled to the patent.

The first step, after the declaration of interference, is to request
that each applicant file a preliminary statement, under oath, in which
he must set forth the following:

First: The date of conception of the invention.

Second: Date of the first reduction to writing, or the preparation of
drawings.

Third: Date of making of the first model or device.

Fourth: When a complete machine was first produced.

These statements are filed in the Patent Office, and opened on the same
day, and times are then set for the respective parties to take
testimony.

If one of the parties was the first to conceive and reduce to practice,
as well as the first to file his application, he will be adjudged to be
the first inventor, without necessitating the taking of testimony.

If, on the other hand, one was the first to conceive, and the other the
first to file, then testimony will be required to determine the question
of invention.

The granting of a patent is not conclusive that the patentee was, in
reality, the first inventor. The law is that the patent must issue to
the _first_ inventor, and if it can be proven that another party was the
first, a new patent will issue to the one who thus establishes his
right. The Commissioner of Patents has no right to take away the patent
first issued. Only the Courts are competent to do this.

A patent is granted for the right to _make_, to _use_ and to _vend_.

An owner of a patent cannot sell the right only to make, or to sell, or
to use. Such a document would be a simple license, only, for that
particular purpose.

A patent may be sold giving a divided, or an undivided right.

A divided right is where a State, or any other particular territorial
right is granted. An undivided right is a quarter, or a half, or some
other portion in the patent itself.

If an inventor assigns his invention, and states in the granting clause
that he conveys "all his right and title in and to the invention," or
words to that effect, he conveys all his rights throughout the world.

If the conveyance says, "all rights and title in and throughout the
United States," he thereby reserves all other countries.

If a patent is issued, and the number and date of the patent are given,
the assignment conveys the patent for the United States only, unless
foreign countries are specifically mentioned.

To convey an invention or patent, some definite number or filing date
must be given in the document, with sufficient clearness and certainty
to show the intent of the assignor.

An invention does not depend on quantity, but on quality. It is that
which produces a new and a useful _result_.

In the United States patents are granted for the purpose of promoting
the useful arts and sciences.

In England, and in many other foreign countries, patents are granted,
not on account of any merit on the part of the inventor, but as a favor
of the crown, or sovereign.

Originally patents were granted by the crown for the exclusive privilege
in dealing in any commodity, and for this right a royal fee was exacted.
>From this fact the term _royalty_ originated.

An international agreement is now in force among nearly all countries,
which respects the filing of an application in any country, for a period
of one year in the other countries.

In making an application for a patent, a petition is required, a
specification showing its object, use, and particular construction,
followed by a claim, or claims, and accompanied by a drawing, if the
invention will permit of it, (which must be made in black, with India
ink), and an oath.

The oath requires the following assertions: That the applicant is the
first and original inventor of the device, and that he does not know
and does not believe the same was ever known or used before his
invention or more than two years before his application.

He must also further allege that the invention was not patented or
described in any printed publication here or abroad, and not
manufactured more than two years prior to the application, and that he
has not made an application, nor authorized any one to do so more than
two years prior to his application.

The first Government fee is $15, payable at the time of filing, and the
second and final fee is $20, payable at the time the patent is ordered
to issue.

The filing of an application for patent is a secret act, and the Patent
Office will not give any information to others concerning it, prior to
the issue of the patent.




GLOSSARY OF WORDS

USED IN TEXT OF THIS VOLUME


Abrupt.          Suddenly; coming without warning.

Abrasive.        A material which wears away.

Actuate.         Influenced, as by sudden motive; incited to action.

Accumulate.      To bring together; to amass; to collect.

Acoustics.       The branch of physics which treats of sound.

Adhesion.        To hold together; a molecular force by means of
                 which particles stick together.

Affinity.        Any natural drawing together; the property or force
                 in chemicals to move toward each other.

Aggravate.       To incite; to make worse or more burdensome.

Alloy.           A combination of two or more metals.

Altitude.        Height; a vertical distance above any point.

Alkali.          Any substance which will neutralize an acid, as lime,
                 magnesia, and the like.

Amalgam.         Any compound of metal which has mercury as one
                 of the elements.

Amiss.           Wrong, fault, misdeed.

Annealing.       A process of gradually heating and cooling metals,
                 whereby hardness and toughness are brought about.

Angle plate.     A metal structure which has two bodies, or limbs,
                 at right angles to each other.

Analysis.        The separating of substances into their elementary
                 forms.

Anchor bolt.     A structure intended to be placed in a hole in a wall,
                 and held there by a brew which expands a part
                 of the structure.

Apprentice.      One who is learning a trade or occupation.

Artificial.      That which resembles the original; made in imitation
                 of.

Arbor.           A shaft, spindle, mandrel, or axle.

Armature.        A metallic body within the magnetic field of a magnet.

Arbitrary.       Stubborn determination. Doing a thing without regard
                 to consequences.

Artisan.         One skilled in any mechanical art.

Attributable.    That which belongs to or is associated with.

Automatically.   Operating by its own structure, or without outside
                 aid.

Augmented.       Added to; to increase.

Auxiliary.       To aid; giving or furnishing aid.

Avoirdupois.     The system of weights, of which the unit is sixteen
                 ounces.

Back-saw.        A saw which has a rib at its upper margin.

Barleycorn.      A grain of barley.

Bastard.         A coarse-grained file.

B. T. U.         British Thermal Unit.

Back-gear.       That gear on a lathe for changing the feed.

Bevel.           Not in a right line; slanting; oblique.

Bibb.            A form of water faucet.

Bit, or bitt.    A form of tool for cutting purposes on a lathe, planer,
                 shaper, or drilling machine.

Borax.           A white crystalline compound, of a sweetish taste.
                 Chemically it is sodium biborate.

Buffs.           Usually a wheel covered with leather or cloth, and
                 having emery dust on it, for fine polishing purposes.

Buffeted.        Thrown back.

Bronze.          An alloy of copper and tin.

Calcium.         Lime.

Cant.            A form of lever.

Carbonate.       A salt of carbonic acid.

Caustic.         Capable of corroding or eating away.

Capillary.       That quality of a liquid which causes it to move
                 upwardly or along a solid with which it is in contact.

Caliper.         An instrument for spanning inside and outside
                 dimensions.

Centripetal.     The force which tends to draw inwardly, or to the
                 center.

Centrifugal.     The outwardly-moving force from a body.

Centering.       To form a point equidistant from a circular line.

Chloride.        A compound of chlorine with one or more positive
                 elements, such as, for instance, salt.

Circular pitch.  The measurement around a gear taken at a point
                 midway between the base and end of the teeth.

Circumference.   The outside of a circular body.

Clef.            A character placed on a staff of music to determine
                 the pitch.

Clutch.          A mechanical element for attaching one part to another.

Chuck, Independent. A disk of metal to be attached to the live spindle
                 of a lathe, and which has on its face a set of dogs
                 which move radially independently of each other.

Chuck, Universal. A disk to be attached as above, provided with dogs
                 which are connected so they move radially in unison
                 with each other.

Classified.      Arranged in order, in such a manner that each of a
                 kind is placed under a suitable heading.

Clearance.       To provide a space behind the cutting edge of a tool
                 which will not touch the work being cut.

Consistency.     Harmonious; not contradictory.

Coherer.         That instrument in a wireless telegraphy apparatus
                 which detects the electrical impulses.

Commutator.      The cylindrical structure on the end of an armature,
                 which is designed to change the polarity of the
                 current.

Concentrated.    Brought together at one point.

Coinage.         The system of making money from metals.

Compound.        The unity of two or more elements.

Constant.        Being insistent and consistent; also a term to be
                 used in a problem which never varies.

Conversion.      The change from one state to another.

Cone.            A body larger at one end than at another; usually
                 applied to a form which is cylindrical in shape
                 but tapering, from end to end.

Compression.     The bringing together of particles, or molecules.

Convolute.       A spiral form of winding, like a watch spring.

Coiled.          A form of winding, like a string wound around a
                 bobbin.

Conductivity.    Applied generally to the quality of material which
                 will carry a current of electricity; also a quality
                 of a material to convey heat.

Cohesion.        The force by which the molecules of the same kind
                 are held together.

Concentric.      A line which is equidistant at all points from a
                 center.

Confined.        Held within certain bounds.

Corpuscular.     Molecular or atomic form.

Converge.        To come together from all points.

Concave.         A surface which is depressed or sunken.

Convex.          A surface which is raised, or projects beyond the
                 surface of the edges.

Component.       One of the elements in a problem or in a compound.

Coefficient.     A number indicating the degree or quality possessed
                 by a substance. An invariable unit.

Cube.            A body having six equal sides.

Cross-section.   A term used to designate that line which is at right
                 angles to the line running from the view point.

Cross slide.     The metal plate on a lathe which holds the tool post,
                 and which is controlled, usually, by a screw.

Contiguous.      Close to; near at hand.

Countersink.     The depression around a bore.

Collet.          A collar, clutch or clamping piece, which has jaws
                 to hold a bar or rod.

Countershaft.    A shaft which has thereon pulleys or gears to connect
                 operatively with the gears or pulleys on a
                 machine, and change the speed.

Conducive.       Tending to; promotive of a result.

Corundum.        An extremely hard aluminum oxide used for polishing.

Cold chisel.     A term applied to an extremely hard chisel used for
                 cutting and chipping metal.

Combustion.      The action or operation of burning.

Conjunctively.   Acting together.

Comparatively.   Similitude or resemblance, one with another.

Cotter.          A key to prevent a wheel turning on its shaft.

Dead center.     A term used to designate the inoperative point of
                 the crank.

Depicting.       Showing; setting forth.

Deodorant.       A substance which will decompose odors.

Developer.       A chemical which will bring out the picture in making
                 the film or plate in photography.

Decimeter.       The length of one-tenth of a meter in the metric
                 system.

Decameter.       The length of ten meters in the metric system.

Defective.       Not perfect; wrong in some particular.

Diaphragm.       A plate, such as used in a telephone system, to receive
                 and transmit vibrations.

Dissolving.      To change from a solid to a liquid condition.

Division plate.  A perforated plate in a gear-cutting machine, to aid
                 in dividing the teeth of a wheel.

Dispelled.       To drive away or scatter.

Disinfectant.    A material which will destroy harmful germs.

Diametral pitch. The number of teeth in a gear as calculated on the
                 pitch line.

Dimension.       Measurement; size.

Ductility.       That property of metal which permits it to be drawn
                 out, or worked.

Dividers.        An instrument, like a compass, for stepping off
                 measurements, or making circles.

Diverge.         Spreading out from a common point.

Drift.           A cutting tool for smoothing a hole in a piece of
                 metal.

Duplex.          Two; double.

Dynamite.        An explosive composed of an absorbent, like earth,
                 combined with nitro-glycerine.

Dynamometer.     An instrument for measuring power developed.

Eccentric.       Out of center.

Echoes.          The reflection of sound.

Effervesce.      The action due to the unity of two opposite chemicals.

Efficiency.      The term applied to the quality of effectiveness.

Ellipse.         A form which is oblong, or having a shape, more or
                 less, like the longitudinal section of an egg.

Electrolytic.    The action of a current of water passing through a
                 liquid, and decomposing it, and carrying elements
                 from one electrode to the other.

Elasticity.      The quality in certain substances to be drawn out
                 of their normal shape, and by virtue of which they
                 will resume their original form when released.

Embedded.        To be placed within a body or substance.

Emerge.          To come out of.

Emphasize.       To lay particular stress upon.

Emery.           A hard substance, usually some of the finely divided
                 precious stones, and used for polishing and grinding
                 purposes.

Enormous.        A large amount; great in size.

Enunciated.      Proclaimed; given out.

Equalization.    To put on an even basis; to make the same
                 comparatively.

Eradicator.      To take out; to cause to disappear.

Escapement.      A piece of mechanism devised for the purpose of giving
                 a uniform rate of speed to the movement of
                 wheels.

Essential.       The important feature; the principal thing.

Expansion.       To enlarge; growing greater.

Equidistant.     The same distance from a certain point.

Evolved.         Brought out of; the result of certain considerations.

Facet.           A face.

Facilitated.     Made easy.

Flux.            Any substance which will aid in uniting material under
                 heat. The act of uniting.

Fluid.           Any substance in which the particles freely interchange
                 positions.

Flour emery.     Emery which is finely ground.

Flexible.        The quality of any material which will permit bending.

Float cut.       The term when applied to a tool where the cut is an
                 easy one.

Flexure.         The springing yield in a substance.

Foot pound.      A unit, usually determined by the number of pounds
                 raised one foot in one second of time. 550 pounds
                 raised one foot in one second of time, means so
                 many foot pounds.

Formulate.       To arrange; to put in order from a certain
                 consideration of things.

Focus.           The center of a circle.

Foci.            One of the points of an ellipse.

Formation.       The structure of a machine or of a compound.

Fractured.       Broken.

Fundamental.     Basis; the first form; the original structure.

Fulcrum.         The resting place for a lever.

Fusion.          Melting. The change of a metal from a solid to a liquid
                 state by heat.

Fusible.         That which is capable of being melted.

Fulminate.       A substance that will ignite or explode by heat or
                 friction.

Gamut.           The scale of sound or light, or vibrations of any kind.

Gear.            A toothed wheel of any kind.

Gelatine.        A tasteless transparent substance obtained from animal
                 tissues.

Globular.        Having the form of a globe or ball.

Glazed.          Having a glossary appearance.

Graphite.        A metallic, iron-black variety of carbon.

Graduated.       To arrange in steps; a regular order or series.

Grinder.         Any mechanism which abrades or wears down a substance.

Gullet.          The curved notches or grooves between projecting parts
                 of mechanism.

Harmonizing.     To make the various parts act together in unison.

H. P.            The symbol for horse power.

Helico.          A form resembling that of the threads of a screw.

Hexagon.         Six-sided.

Heliograph.      The system of signaling by using flashlights.

Horizontal.      Things level with the surface of the earth; like the
                 surface of water.

Hydrogen.        The lightest of all the elements. A tasteless,
                 colorless substance.

Import.          To bear, or convey as a meaning.

Impulse.         The application of an impelling force.

Impact.          A collision; striking against.

Invariably.      Constant; without failing.

Inertia.         The quality of all materials to remain at rest, or to
                 continue in motion, unless acted on by some external
                 force.

Intersect.       To divide at a certain point. The crossing point of one
                 line over another.

Interval.        A space; a distance between.

Intensity.       Strained or exerted to a high degree.

Interstices.     The spaces between the molecules or atoms in a
                 substance.

Intermediate.    Between.

Intermeshing.    The locking together of gear wheels.

Internal.        That which is within.

Inability.       Unable to perform or do.

Initial.         The first; at the start.

Increment.       One of the parts which go to make up the whole.

Inference.       Drawing a conclusion from a certain state of things.

Insoluble.       A substance which cannot be liquefied by a liquid.

Indentations.    Recesses, or cut-out parts or places.

Induction.       The movement of electricity through the air from
                 one conductor to another.

Inflammable.     That which will burn.

Inclining.       At an angle; sloping.

Inconsequential. Not of much importance.

Isometric.       That view of a figure which will give the relation
                 of all the parts in their proper proportions.

Jaw.             The grasping part of a vise, or other tool.

Joule.           The practical unit of electrical energy.

Key-way.         A groove in a shaft and in the hub of a wheel, to
                 receive therein a locking key.

Kilowatt.        A unit of electrical power; one thousand watts.

Kinetic.         Consisting of motion.

Lacing.          The attaching of the ends of a belt to each other.

Lap.             A tool, usually of copper or lead, on which flour emery
                 is spread, with oil, and used to grind out the interior
                 of cylinders.

Lapping.         The act of using a lap to grind out cylinders.

Lacquer.         A varnish for either wood or metal.

Lazy-tongs.      A form of tool, by means of which a long range of
                 movement is attainable, and great grasp of power.

Levigated.       Reduced to a fine powder.

Litharge.        A form of lead used in paints for drying purposes.

Longitudinal.    Lengthwise.

Luminous.        That which has the capacity to light up.

Magnet.          A bar of iron or steel that has electricity in it
                 capable of attracting certain metals.

Manipulation.    Capable of being handled.

Mandrel.         The revolving part of a lathe; a rod or bar which
                 turns and carries mechanical elements thereon.

Manually.        Operated by hand.

Margin.          An edge.

Malleability.    Softness. The state of being formed by hammering.

Magnetism.       A quality of certain metals to receive and hold a
                 charge of electricity.

Major axis.      The measurement across the longest part of an ellipse.

Minor axis.      The distance across the narrowest part of an ellipse.

Meridian.        The time when the sun crosses the middle of the
                 heavens; midday.

Metric.          Measure; a system which takes the unit of its
                 measurement from the circumference of the earth.

Micrometer.      A tool for measuring small spaces or intervals.

Milling machine. A large tool for the purpose of cutting gears and
                 grooves or surfaces.

Miter.           A meeting surface between two right-angled pieces.

Momentum.        That quality of matter which is the combined energy
                 of mass and speed.

Molecular.       Any substance that is made up of any particles; the
                 component elements in any substance.

Modifications.   Changes; improved arrangements.

Multiplicity.    Many; numerous; a large quantity.

Mutilated.       As applied to a gear, one in which certain teeth are
                 removed.

Nautical.        Marine; applied to shipping, and the like.

Neutralizes.     Any substance, like a chemical, which, when added
                 to another chemical, will change them both.

Nitro-glycerine. An explosive made from glycerine and nitrogen.

Oblique.         At an angle; inclined.

Obliterate.      To wipe out.

Obvious.         That which can be seen; easily observed.

Obtuse.          A blunt angle; not noticeable.

Odophone.        An instrument for determining and testing odors.

Olfactory.       The nerves of the sense of smell.

Orifice.         An opening; a hole.

Oscillation.     A movement to and fro, like a pendulum.

Oxygen.          The most universal gas, colorless and tasteless; is
                 called the acid-maker of the universe and unites
                 with all known substances, producing an acid, an
                 alkali, or a neutral compound.

Oxidizing.       To impart to any substance the elements of oxygen.

Oxide.           Any substance which has oxygen added to it.

Pallet.          A part of a tooth or finger which acts on the teeth
                 of a wheel.

Parallel.        Lines or sides at equal distance from each other from
                 end to end.

Paraffine.       A light-colored substance, produced from refined
                 petroleum.

Perimeter.       The outer margin of a wheel; the bounding line of any
                 figure of two dimensions.

Periphery.       The outer side of a wheel.

Peen.            The nailing end of a hammer.

Persistence.     That quality of all matter to continue on in its
                 present condition.

Perpendicular.   A line drawn at right angles to another.

Perpetual.       Without end.

Perspective.     A view of an object which takes in all parts at one
                 side.

Physically.      Pertaining to the body.

Phonautograph.   An apparatus for recording sound.

Phonograph.      An apparatus for taking and sending forth sound
                 vibration.

Phenomena.       Any occurrence in nature out of the ordinary.

Pitman.          The rod or bar which connects the piston and crank.

Pivot.           A point or bar on which anything turns.

Pinion.          A small toothed wheel.

Pitch.           The number of vibrations. The term used to give the
                 number of teeth in a wheel.

Pitch diameter.  The point from which the measurements are made in
                 determining the pitch.

Pivoted.         A bar, lever, or other mechanical element, arranged to
                 turn on or about a point.

Plastic.         A substance in such a state that it may be kneaded or
                 worked.

Planer.          A large tool designed to cut or face off wood or metal.

Porosity.        The quality in all substances to have interstices,
                 or points of separation, between the molecules.

Potential.       The power.

Properties.      The qualities possessed by all elements.

Projecting.      The throwing forward. The sending out.

Promulgated.     Put forth; enunciated.

Protractor.      A mechanic's and draughtsman's tool by means of
                 which angles may be formed.

Promote.         To carry forward in a systematic way.

Precision.       Work done with care; observing correct measurements.

Prony brake.     A machine for determining horse power.

Punch.           A small tool to be struck by a hammer in order to
                 make an impression or indentation.

Quadrant.        One-fourth of a circle.

Quadrant plate.  A plate on which are placed lines and numbers
                 indicating degrees.

Quadruplex.      A term to designate that system of telegraphy in
                 which four messages are sent over a single wire at
                 the same time.

Ratchet.         A wheel having teeth at certain intervals to catch
                 the end of a pawl or finger.

Ratchet brace.   A tool to hold a drill, having a reversible ratchet
                 wheel.

Rasp cut.        A cut of a file which is rough, not smooth.

Rake.            The angle or inclination of the upper surface of the
                 cutting tool of a lathe.

Reverse.         To turn about; in the opposite direction.

Reciprocating.   To go back and forth.

Revolve.         To move in an orbit or circle, as a merry-go-round.

Reciprocity.     To give back in like measure.

Reflection.      The throwing back from a surface.

Resonance.       The quality of vibration which adds to the original
                 movement, and aids in perpetuating the sound.

Refraction.      The quality of light which causes it to bend in passing
                 through different substances.

Reducing.        Bringing it down to a smaller compass.

Rectilinear.     A straight line.

Retort.          A furnace of refractory material to take high heat.

Reamer.          A tool designed to enlarge or to smooth out holes.

Regulation.      To do things in an orderly way; a system which sets
                 forth certain requirements.

Refractory.      Difficult to work, and not easily fused.

Recess.          A hole, or a depression.

Rocking.         A lever which rotates only part way and then moves in
                 the opposite direction.

Rotate.          A spindle which turns round. Compare revolve.

Rosin.           Certain gums; particularly the sap of pine trees.

Roughing.        The taking off of the first coating with a tool.

Saturated.       A soluble substance which cannot be further dissolved
                 by a liquid.

Scribe.          To mark with a tool.

Screw plate.     A tool which has within it means for adjusting
                 different cutting tools.

Section lining.  The marks made diagonally across drawings to indicate
                 that the part is cut away.

Shaper.          A large tool for surfacing off material, cutting
                 grooves, and the like.

Shrinkage.       The term applied to metals when cast, as all will be
                 smaller when cold than when cast in the mold.

Slide rest.      The part of the lathe which holds the tool post.

Sonorous.        Having the quality of vibration.

Slotted.         Grooved, or channeled.

Solvent.         That which can be changed from a solid by liquids.

Spelter.         A combination of zinc and copper. A hard solder.

Soldering.       Uniting of two substances by a third, with heat.

Spindle.         A small shaft.

Spur.            The larger of two intermeshing gears.

Socket.          A depression or hole.

Sprocket.        Teeth in a wheel to receive a chain.

Spiral.          A form wound like the threads of a screw.

Surface plate.   A true surface made of metal, used as a means of
                 determining evenness of the article made.

Sulphate.        Any substance which is modified by sulphuric acid.

Substitute.      An element or substance used for another.

Superposed.      One placed above the other.

Swage.           Tool for the purpose of changing the form in a
                 material.

Swivel.          A point on which another turns.

Surfacing.       Taking off the outer coating or covering.

Tap.             A small drill.

Tapering.        An object with the sides out of parallel.

Tangential.      A line from the periphery of a circle which projects
                 out at an angle.

Tension.         The exertion of a force.

Tenacity.        The property of a material to hang together.

Tempering.       Putting metal in such condition that it will be not
                 only hard but tough as well.

Technical.       Pertaining to the strict forms and terms of an art.

Texture.         That of which the element or substance is composed.

Threads.         The ridges, spiral in form, which run around a bolt.

Theoretically.   The speculative form or belief in a subject.

Tinned.          The term applied to the coating on a soldering iron
                 with a fluxed metal.

Tines.           Small blades.

Torsion.         The force exerted around an object, like the action of
                 a crank on a shaft.

Tommy.           A lever to be inserted in a hole in a screw head for
                 turning a screw.

Transmitting.    Sending forth; to forward.

Trammel.         A tool for the purpose of drawing ellipses.

Traction.        Drawing; pulling power.

Tripping.        A motion applied to a finger, which holds a pivoted
                 arm, whereby the latter may be swung from its
                 locked position.

Triangular.      Having three sides and three angles.

Transverse.      Across; at right angles to the long direction.

Undercut.        A wall of a groove or recess which is sloping.

Undulatory.      A wave-like motion, applied generally to light and
                 electricity.

Unit.            A base for calculating from.

Unison.          Acting together; as one.

Unsized.         Generally applied to the natural condition of paper
                 or fabric which has no glue or other fixing substance
                 on it.

Vaporising.      To change from a liquid or solid to a gas.

Variation.       Changing into different conditions; unlike forms.

Verge.           The edge; usually applied to the shoulder of a watch
                 spindle, particularly to the escapement.

Vertical.        Up and down. The direction of a plumb line.

Velocity.        The speed of an article through space.

Vitascope.       An instrument for determining the rate of vibration of
                 different substances.

Vibration.       The movement to and fro of all elements, and by means
                 of which we are made sensitive of the different forces.

Vocation.        The business or the calling of a person.

Warding.         The act of cutting a projection or guard, such as is
                 usually found on the insides of locks, and the
                 correspondent detent in the key.

Watt.            In electricity the unit of the rate of working in a
                 circuit.  It is the electro-motive force of one volt
                 and the current intensity of one ampere.




INDEX

(Figures indicate the pages)


A

Acetone, 165.

Acid, 119, 120, 156, 168.

Acid, Acetic, 165.

Acid, Carbolic, 166.

Acid, Hydrofluoric, 170.

Acid, Muriatic, 119.

Acid, Nitric, 168, 169, 171, 173.

Acid, Oxalic, 172.

Acid, Pyrogallic, 172.

Acid, Sulphuric, 169.

Acoustics, 87, 157.

Adhesives, 162.

Affinity, 83, 86.

Agate, 82.

Air, 84.

Alcohol, 165, 166, 169, 170, 176, 183.

Alloy, 81, 115, 116, 118, 119, 149, 175.

Alum, 149, 166, 172.

Aluminum, 38, 41, 42, 60, 82, 149, 164, 166, 169, 170, 174, 175, 176,
          184.

Amalgams, 149.

Amber, 170.

Ambergris, 159.

Ammonia, 166, 170.

Ammonium Nitrate, 185.

Ammonium Sulphate, 168, 171.

Analysis, 93.

Analyzed, 159.

Angle cutting, 30.

Angle plate, 10.

Angles, 31, 39, 59, 72, 102, 103, 104, 107, 152.

Aniline, 176.

Annatto, 168, 170.

Annealing, 112, 113, 114, 115.

Annular, 67.

Anvils, 14, 15, 16.

Apothecaries, 180.

Application for patent, 191.

Arbor, 14.

Arc, 146.

Area, 148.

Armature, 153.

Arrow root, 150.

Artisan, 112.

Asbestos, 168.

Asphalt, 14, 175.

Assign, 191, 193.

Assignment, 192.

Atom, 157.

Attraction, 86.

Avoirdupois, 180.

Axis, 106, 127.

Axis, major, 105.

Axis, minor, 105, 106.


B

Ball, 75.

Ball and Socket, 74.

Balsam Peru, 168, 189, 173.

Barium Chloride, 176.

Bark, soap, 165.

Barleycorn, 143.

Barrel, 149.

Base line, 102.

B. T. U., 180, 181.

Beeswax, 174.

Bell metal, 164.

Belt, 68.

Belt, Lacing, 68, 69.

Bench, 77, 104.

Benzine, 169.

Benzol, 173.

Bevel, 69, 70, 125, 126.

Bibb, 70.

Bismuth, 118.

Bisulphate of carbon, 185.

Bisulphate of sodium, 172.

Bitt, 28, 42.

Bitts, machine, 38.

Bitts, plain, 38.

Bitts, round-nosed, 38.

Bitts, setting, 39.

Bitts, square, 38.

Black, ivory, 171.

Blade, hack-saw, 35, 36.

Bloodstone, 173.

Blue black, 173.

Boiler, 150, 152.

Boiler, compound, 161.

Bolt, 75.

Bolt, anchor, 7.

Boracic acid, 168.

Borax, 168, 176.

Brass, 41, 43, 44, 168, 170, 174, 175, 176, 184.

Bronze, 150, 164, 173, 176, 184.

Bulk, 134.


C

Calcium, 166.

Calcium Chloride, 185.

Calipers, 37, 45, 49, 66.

Calls, 160.

Camphor, 164, 166, 175.

Canada balsam, 172.

Capillary attraction, 86, 87.

Carbolic acid, 166.

Carbon, 113.

Carbonate, 150.

Carbonate of soda, 116, 172.

Carbon paper, 171.

Cardinal, 102.

Carbolized, 169.

Cast iron, 42, 64, 81, 169, 183.

Caustic soda, 106, 150.

Caveat, 190.

Celluloid, 164.

Cement, 162, 163.

Centaire, 146.

Center, dead, 78.

Center line, 41.

Centering, 111.

Centers, 62.

Centimeter, 146.

Centrifugal, 85.

Centripetal, 85.

Ceresine, 174.

Chalk, 165.

Channel, 71.

Charcoal, 113, 167, 185.

Chemical, 83, 157, 180.

Chisels, drifting, 32.

Chisels, key-way, 32.

Chisels, square, 53.

Chlorate of potash, 167, 169, 170.

Chloride of lime, 165.

Chloride of platinum, 173.

Chloride of tin, 119.

Chloride of zinc, 163, 176.

Chloral hydrate, 169.

Chloroform, 163.

Chromate of potash, 169, 170.

Chuck, 54.

Chuck, independent, 64.

Chuck, universal, 64.

Circle, 96, 106, 107, 111, 148, 169.

Circuit, 153, 154.

Circular pitch, 122, 124, 125.

Circumference, 148.

Citric, 165.

Clamp, 77.

Clay, 164, 185.

Clearance, 30, 38, 40.

Clef, 159.

Clutches, 74.

Coal, 139.

Coherer, 154.

Cohesion, 50, 83.

Color, 92, 157, 161.

Combination, 136, 156.

Commutator, 155.

Compass, 106.

Compound, Welding, 117.

Compression, 77, 84.

Compressibility, 84.

Concave, 92, 93.

Concentric, 88.

Conception, 191.

Conductivity, 82.

Conductor, 82, 88.

Cone, 70.

Conveyor, 91.

Convex, 92, 96.

Convolute, 78.

Copal varnish, 163.

Copper, 45, 60, 112, 118, 164, 170, 173, 174, 184.

Corpuscular, 91.

Corundum, 27.

Crank, 70, 76, 78, 135.

Cream of Tartar, 165, 174.

Crown wheel, 70.

Cryolite, 176.

Cube, 97, 98, 107, 149.

Current, 154, 158.

Curve, 104.

Cutter, side, 30.

Cutting tool, 171.

Cyanide of Potassium, 170.

Cylinder, 39, 40, 66, 80, 90, 134, 135, 136.


D

Decameter, 146, 106, 109, 183, 187.

Decimeter, 146.

Declaration of Interference, 190.

Degree, 40, 101, 102, 103, 104.

Deodorant, 166.

Dessertspoon, 151.

Detail, paper, 111.

Develop, 157.

Developer, 172.

Dextrine, 169.

Diameter, 52, 126, 140, 143, 144, 148, 149, 150.

Diameter, inside, 122.

Diameter, outside, 122.

Diameter, pitch, 122.

Diametral pitch, 123, 124.

Diamond, 81, 149.

Diaphragm, 90, 153, 154.

Disinfectant, 163.

Disks, 49, 50, 67, 71, 74, 75, 82, 91, 95, 96, 105.

Disk shears, 90, 153, 154.

Distilled, 144, 151.

Diverge, 91.

Divided, 192.

Dividers, 45, 52, 62, 63.

Dogs, 77.

Dollar, 144.

Drams, 180.

Drawing, 95, 97, 101, 108, 109, 129, 191.

Drill, 30, 31.

Drilling Machine, 43.

Driver, 73.

Dry measure, 182.

Ductility, 80, 81.

Dynamite, 167.

Dynamo, 155.


E

Eccentric, 78.

Echo, 89.

Effervesce, 119.

Elastic, 91.

Elasticity, 87, 112.

Electrical, 82, 153, 154, 155.

Electric current, 182.

Electric curves, 182.

Electricity, 78, 84, 93.

Electrolytic, 149.

Electro-motive force, 154.

Ellipse, 72, 104, 105, 106, 107.

Emery, 27, 36, 150, 165, 166, 167.

Emery cloth, 55.

Emery wheel, 22.

Energy, 140.

Engine, 45, 78, 134.

Equalization, 82.

Escapement, 72.

Ether, 91, 169.

Expansion, 93.

Explosions, 156, 167.


F

Facet, 52.

Fahrenheit, 148, 186.

Feed, longitudinal, 66.

Feed, transverse, 66.

Ferric chloride, 166.

Filament, 160.

File, cross, 57.

File, cutter, 56.

File, do-able end, 57, 58.

File, equalizing, 57.

File, float cut, 57.

File, half round, 56.

File, holding, 59.

File, middle, 57.

File, movement, 59, 80.

File, pinion, 56.

File, rasp cut, 57.

File, rat-tail, 56.

File, rough, 57.

File, round, 56.

File, saw, 56.

File, second cut, 57.

File, shearing cut, 59.

File, slitting, 57.

File, smooth, 57.

File, square, 56.

File, triangular, 56.

Files, 36, 48, 50, 52, 53, 56, 59, 60, 114, 167, 168.

Files, Hexagon, 51, 52.

Filing, 52, 53, 54, 55, 56, 61.

Filter paper, 171.

Fire clay, 164, 165.

Fish oil, 171,176.

Fire proof, 168, 171.

Flexure, 79.

Floor dressing, 168.

Fluid, 165.

Fluor spar, 116.

Fluxes, 115, 116, 118, 176.

Focal, 106, 107.

Focus, foci, 105.

Foot, 145.

Foot lathe, 78.

Foot pounds, 139, 140, 143, 181.

Force, 156, 157.

Forge work, 116.

Forges, 164.

Formic acid, 168.

Formula, 162.

Freezing mixtures, 185.

Friction, 70, 171.

Fuel, 134, 181.

Fulcrum, 76, 128, 129.

Fulminate, 167.

Furlong, 181.

Furniture, 164.

Fusible, 116.

Fusion, 115.


G

Gage, 45, 46, 47, 148.

Gage surface, 84, 87, 94.

Gallon, 144.

Gas stove, 166.

Gear, 42, 69, 70, 74, 121, 122, 123, 125, 126, 133, 171.

Gear, bevel, 70.

Gear, friction, 70.

Gearing, 121.

Gear, miter, 70, 123, 124, 125, 126.

Gear, mutilated, 72.

Gear, spur, 122.

Gelatine, 162, 173.

Geranium, 169.

German silver, 82.

Giant powder, 167.

Glass, 84, 92, 112, 163, 169.

Glauber salts, 164.

Glazing, 72.

Glue, 159, 162, 168.

Glycerine, 115, 162, 165, 176.

Gold, size, 173.

Grain, 81.

Grains, 180.

Graphite, 171, 175.

Gravity, 85.

Grinder, 27.

Grinder wheels, 36.

Grindstones, 22, 36, 149.

Groove, 71, 76.

Gum, 163.

Gum arabic, 163.

Gum lac, 170.

Guncotton, 188.

Gunpowder, 167.


H

Hack-saw, 34, 35, 36.

Hack-saw blade, 35, 36.

Hammer, 81, 115, 117.

Handy tables, 178.

Hardness, 81, 114, 115.

Harmony, 154, 158, 169, 160.

Head, 135.

Heat, 93, 186.

Hectare, 146.

Hectometer, 146.

Helical, 77.

Helical, double, 77.

Helix-volute, 77.

Hexagon, 51, 52.

Horizontal, 97, 102, 106.

Horse power, 139, 143, 146, 148, 186, 187.

Hours, H. P., 186, 187.

Hours, kilowatt, 186, 187.

Hub, 74.

Hub, key-way, 125.

Hydrochloric acid, 172.

Hydrofluoric acid, 149.

Hydrogen, 83.


I

Inches, 181.

Inclined plane, 123, 128.

Indentation, 154.

Indicator, speed, 140.

Induction, 154.

Inertia, 84.

Injector, 152.

Inks, 110.

Inside diameter, 122.

Instrument, 158, 159.

Internal, 86, 102.

International, 193.

Invention, 152, 153, 161, 188, 189, 190, 192, 193, 194.

Inventor, 157, 181, 190.

Iron, 42, 63, 155, 162, 165, 169, 175, 184.

Iron, wrought, 42, 82, 112.

Isinglass, interference, 190.

Isometric, 107.

Ivory, 84.

Ivory, black, 171.


J

Japan wax, 174.

Joint, ball and socket, 74.

Joint, universal, 70.

Joule, 174.


K

Kerosene, 150, 165, 171.

Key, 158.

Key-way, 125.

Kilometer, 146.

Kilowatt, 186, 187.

Kilowatt hour, 186, 187.

Kinetic, 140.


L

Lacquer, 170.

Lampblack, 167, 175.

Lapping, 166, 167.

Lathe, 28, 39, 42, 45, 64, 65, 67, 104, 171.

Lathe speed, 34.

Lathe tool, 33, 39.

Lavender, 168.

Lead, 60, 118, 163, 164,175.

Leather, 162, 163.

Level, 87.

Lever, 73, 75, 76, 128, 129, 130, 131, 132, 133, 140, 153.

Leverage, 143.

Licenses, 189.

Light, 100.

Lime, 173.

Linear measure, 181.

Lines, 95, 99, 110.

Lines, section, 84.

Linseed, 162.

Linseed oil, 149, 174,175.

Liquid measure, 182.

Liquids, 84.

Litharge, 163.

Long measure, 181.

Lubricant, 171.

Luminous, 91.

Lycopodium, 169.


M

Machine, 26.

Magnesium, 166.

Magnesium sulphate, 169.

Magnet, 153.

Magnetism, 93.

Major axis, 105.

Malleability, 81.

Malleable, 112.

Mandrel, 66, 76.

Manganese, 163.

Marble, 162.

Mass, 85.

Mastic, 169.

Measure, 139, 140, 143, 151.

Measure, liquid, 182.

Measure, long, 181.

Measurement, 145.

Measure, paper, 182.

Measure, solid, 82.

Measure, square, 181.

Membrane, 90.

Mercuric chloride, 166.

Mercury, 94, 114, 183.

Meridian, 145.

Metric, 144, 145, 146.

Metrical, 145.

Micron, 146.

Microscope, 91.

Millimeter, 146.

Milling machine, 26.

Minor, 164.

Minor axis, 105, 106.

Miter, 146.

Miter gear, 123, 124, 125, 126.

Molecular, 82, 117.

Molecular forces, 82.

Molecules, 83, 84, 146.

Momentum, 83, 85.

Motion, 84, 156.

Motor, 136, 155.


N

Neat's Foot oil, 168.

Neroli, 168.

Nickel, 164.

Nitrate of copper, 174.

Nitrate of potash, 167.

Nitrate of silver, 174.

Nitric acid, 162, 168, 169, 171, 173.

Nitro-glycerine, 167, 185.


O

Oath, 193.

Octave, 159.

Odophone, 159.

Odor, 159.

Oil, 83, 87, 167, 171.

Oil eradicator, 166.

Oleonaptha, 171.

Oscillations, 90, 157.

Ounce, 180.

Outlines, 99.

Oxalic acid, 172.

Oxidation, 117.

Oxide, 117, 163.

Oxidizing, 116.

Oxygen, 83, 119.


P

Palm oil, 171.

Paper, 168, 171.

Paraffine, 168, 171.

Parallel, 91, 100, 121.

Paris blue, 172.

Paste, 163, 173.

Patents, 188, 189, 190, 192, 194.

Pawl, 73, 76.

Pendulum, 73.

Parting tools, 28.

Perimeter, 73.

Periphery, 73.

Permanganate of potash, 178.

Perpendicular, 105.

Perpetual motion, 128.

Perspective, 97, 106, 107.

Petroleum, 168.

Phenomenon, 91, 153.

Phonautograph, 90.

Phonograph,-91, 154.

Phosphorus, 149.

Photographer, 157, 172.

Piano, 158, 159.

Pinion, 57, 74.

Pitch, 121, 125, 156.

Pitch, circle, 122, 124, 125.

Pitch, diameter, 123, 124.

Pitch, line, 123, 124, 127.

Pitman, 70.

Pivots, 70, 130.

Planer, 26, 50, 51, 126.

Plaster, 173.

Plaster of Paris, 150, 174.

Plate, 73.

Plates, 50.

Plating, 173.

Platinum, 81.

Plumbago, 173.

Poles, 155.

Polishes, 174.

Position, 102.

Potash, 116, 167.

Potash, prussiate, 113.

Potassium cyanide, 170.

Potassium nitrate, 167.

Pound, 145, 157, 180.

Power, 128, 129, 130, 131, 133, 134, 140, 158, 159, 186.

Power, horse, 139, 140.

Precision tools, 50.

Preliminary statement, 191.

Pressure, 134, 135, 137, 148, 152.

Prime mover, 134.

Printing telegraph, 155.

Prism, 92, 93.

Protractor, 108, 109.

Prussiate of potash, 113.

Pulley, 68, 70, 73, 128, 133, 140, 149, 150.

Pulsation, 153.

Pumice, 83.

Pumice stone, 110, 175.

Punch, 62, 63.

Punch, centering, 62.

Punch cutter, 24.

Putty, 175.


Q

Quadrant, 102, 103.

Quality, 157.

Quarter, 180.

Quartz, 182.


R

Racks, 73, 74.

Radius, 52.

Rake, 29, 30, 38, 42, 43,45.

Rainbow, 92.

Ratchet, 77.

Ratchet brace, 77.

Reciprocity, 82.

Reflected, 92.

Reflecting, 89.

Reflection, 88, 91.

Refraction, 92.

Resin, 176.

Resistance, 79, 82, 83.

Resonance, 89.

Rim, 96.

Ring, 96.

Rods, 180.

Rosemary, 166.

Royalty, 193.

Rubber, 84, 163.

Rule, 53.

Rule, key-seat, 53, 54.

Rust preventive, 175.


S

Saffro, 170.

Sal ammoniac, 119, 162, 165, 176, 185.

Salt, 165, 170, 183, 185.

Sandarac, 169, 176.

Saw, 26, 64, 76.

Saw, wabble, 76.

Scale, 100, 101.

Science, 157.

Scraper, 50, 51.

Scribe, 47, 53.

Scruples, 180.

Sealing wax, 176.

Section lining, 103, 104, 110.

Sense, 159.

Sesame oil, 176.

Shade, 96.

Shading, 96, 110.

Shaft, 68, 69, 70, 73, 74, 75.

Shaft coupling, 74.

Shaper, 26, 50, 51, 53.

Shellac, 163.

Side cutters, 30.

Sienna, 168.

Signals, 87.

Silicate, 168.

Silver, 82, 118, 164, 165, 180, 183.

Snow, 185.

Soap, 165, 172.

Soap spirits, 166.

Soda, sulphate, 172.

Sodium carbonate, 172.

Sodium silicate, 168.

Sodium sulphate, 172.

Solder, 118, 175.

Solder, hard, 118.

Solder, soft, 118.

Soldering, 116, 117, 119, 176.

Solids, 84.

Sonorous, 88.

Sound, 87.

Sounding-boards, 88.

Spanish white, 168.

Spectroscope, 90, 93, 161.

Spectrum, 93.

Speed, 43.

Spelter, 118.

Sphere, 97.

Spiral, 78.

Sponge, 83.

Spring, 72, 79, 176.

Square, 48, 61, 63.

Square combination, 24, 77, 81.

Starch, 162, 163, 164.

Steel, 39, 40, 42, 44, 63, 79, 113, 165, 168, 169, 170, 184.

Stethoscope, 90.

Stove polish, 174, 175.

Straight edge, 61.

Stylus, 90.

Sugar, 163.

Sulphate of copper, 174.

Sulphate of potash, 115.

Sulphate of soda, 172.

Sulphur, 167, 183.

Sulphuric acid, 165, 169, 175.

Surfacing, 49, 50, 63.


T

Table of weights, 178.

Talcum, 169.

Tallow, 176.

Tannaform, 169.

Taps, 45.

Taste, 160.

Teeth, 72.

Telegram, 158.

Telescope, 91, 92.

Temperature, 82, 88, 114, 116, 118, 119.

Temperature table, 180.

Tempering, 113, 114, 115,176.

Tenacity, 79, 80.

Thread, 74.

Thymol, 166.

Tin, 98, 118, 175, 176, 184.

Ton, 180.

Tongs, 75.

Tongs, lazy, 75.

Tool, 22, 28, 40, 41, 61, 64, 71, 108, 113, 175.

Tool boring, 43.

Tool cutting, 26, 29, 45, 64.

Tool holder, 64.

Tool hook, 28.

Tool, hooked, 44.

Tool knife, 28.

Tool, parting, 28.

Tool, roughing, 29.

Tools, precision, 50.

Torsion, 79.

Toughness, 114, 115.

Tracing cloth, 110.

Tracing paper, 172.

Traction, 79.

Transmitting, 158.

Transparent, 163.

Transverse, 80.

Treadle, 78.

Triangular, 97, 98.

Tripping driver, 78.

Turmeric, 170.

Turpentine, 162, 165, 172, 173, 174, 175.

Turpentine, Venice, 176, 177.


U

Ultramarine, 171.

Undivided, 192.

Undulatory, 91.

Unguent, 114.


V

Valve, 70.

Vapor, 87.

Varnish, 162, 170, 172, 175, 176.

Vaseline, 165, 175.

Velocity, 81, 87, 91.

Vermilion, 177.

Vertical, 97.

Vibrate, 160, 161.

Vibration, 87, 88, 90, 158.

Vibratory, 91.

Vinegar, 163, 170, 173.

Violin, 159.

Vise, 33.

Vitascope, 90.


W

Water, 165, 166, 168, 172, 183, 186, 187.

Waterproof, 162, 163.

Weight, 85.

Weight of steel, 179.

Weight, troy, 180.

Welding, 115, 116, 117.

Welding compound, 117.

Wheel, 27, 72, 73, 85, 86.

Whiting, 174.

Workshop, 162.

Wrench, 104.


Y

Yokes, 70, 76.


Z

Zinc, 118, 119, 164, 166, 175.

Zinc chloride, 163.




THE BOYS' ELITE SERIES

_12mo, cloth. Price 75c each._

Contains an attractive assortment of books for boys by standard and
favorite authors. Printed from large, clear type on a superior quality
of paper, bound in a superior quality of binders' cloth, ornamented with
illustrated original designs on covers stamped in colors from unique and
appropriate dies. Each book wrapped in attractive jacket.

1. Cudjo's Cave                              Trowbridge
2. Green Mountain Boys
3. Life of Kit Carson                   Edward L. Ellis
4. Tom Westlake's Golden Luck            Perry Newberry
5. Tony Keating's Surprises    Mrs. G. R. Alden (Pansy)
6. Tour of the World in 80 Days             Jules Verne


THE GIRLS' ELITE SERIES

_12mo, cloth. Price 75c each._

Contains an assortment of attractive and desirable books for girls by
standard and favorite authors. The books are printed on a good quality
of paper in large clear type. Each title is complete and unabridged.
Bound in clothene, ornamented on the sides and back with attractive
illustrative designs and the title stamped on front and back.

1. Bee and the Butterfly     Lucy Foster Madison
2. Dixie School Girl        Gabrielle E. Jackson
3. Girls of Mount Morris          Amanda Douglas
4. Hope's Messenger         Gabrielle E. Jackson
5. The Little Aunt           Marion Ames Taggart
6. A Modern Cinderella            Amanda Douglas


_For sale by all Booksellers, or sent postpaid on receipt of 75c_




THE "HOW-TO-DO-IT" BOOKS

By J. S. ZERBE


Carpentry for Boys

A book which treats, in a most practical and fascinating manner all
subjects pertaining to the "King of Trades"; showing the care and use of
tools; drawing; designing, and the laying out of work; the principles
involved in the building of various kinds of structures, and the
rudiments of architecture. It contains over two hundred and fifty
illustrations made especially for this work, and includes also a
complete glossary of the technical terms used in the art. The most
comprehensive volume on this subject ever published for boys.


Electricity for Boys

The author has adopted the unique plan of setting forth the fundamental
principles in each phase of the science, and practically applying the
work in the successive stages. It shows how the knowledge has been
developed, and the reasons for the various phenomena, without using
technical words so as to bring it within the compass of every boy. It
has a complete glossary of terms, and is illustrated with two hundred
original drawings.


Practical Mechanics for Boys

This book takes the beginner through a comprehensive series of practical
shop work, in which the uses of tools, and the structure and handling of
shop machinery are set forth; how they are utilized to perform the work,
and the manner in which all dimensional work is carried out. Every
subject is illustrated, and model building explained. It contains a
glossary which comprises a new system of cross references, a feature
that will prove a welcome departure in explaining subjects. Fully
illustrated.

_12mo, cloth. Price $1.00 each._


_For sale by all Booksellers, or sent postpaid on receipt of $1.00._




The American Boy's Sports Series

BY MARK OVERTON

12 Mo Cloth. Illustrated. Price 60c Each.

       *       *       *       *       *

These stories touch upon nearly every sport in which the active boy is
interested. Baseball, rowing, football, hockey, skating, ice-boating,
sailing, camping and fishing all serve to lend interest to an unusual
series of books. There are the following four titles:

1. Jack Winters' Baseball Team; or, The
   Mystery of the Diamond.

2. Jack Winters' Campmates; or, Vacation
   Days in the Woods.

3. Jack Winters' Gridiron Chums; or, When
   the Half-back Saved the Day.

4. Jack Winters' Iceboat Wonder; or, Leading
   the Hockey Team to Victory.

       *       *       *       *       *

Phil Bradley

Mountain Boy's Series

BY SILAS R. BOONE

12 Mo. Cloth. Illustrated. Price 60c Each

       *       *       *       *       *

These books describe with interesting detail the experience of a party
of boys among the mountain pines. They teach the young reader how to
protect themselves against the elements, what to do and what to avoid,
and above all to become self-reliant and manly. There are five titles:

1. Phil Bradley's Mountain Boys; or, The
   Birch Bark Lodge.

2. Phil Bradley at the Wheel; or, The Mountain
   Boys' Mad Auto Dash.

3. Phil Bradley's Shooting Box; or, The
   Mountain Boys on Currituck Sound.

4. Phil Bradley's Snow-shoe Trail; or, The
   Mountain Boys in the Canadian Wilds.

5. Phil Bradley's Winning Way.

       *       *       *       *       *

For sale by all Booksellers, or sent postpaid on receipt of 60c.




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Contains an assortment of attractive and desirable books for girls by
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of paper in large clear type. Each title is complete and unabridged.
Bound in clothene, ornamented on the sides and back with attractive
illustrative designs and the title stamped on front and back.

_12mo, clothene. Price 50c each._

 1. Camp Fire Girls on a Long Hike, or,
    Lost in the Great Northern Woods     Stella M. Francis

 2. Daddy's Girl                          Mrs. L. T. Meade

 3. Ethel Hollister's First Summer as
    a Camp Fire Girl                  Irene Elliott Benson

 4. Ethel Hollister's Second Summer   Irene Elliott Benson

 5. Flat Iron for a Farthing                    Mrs. Ewing

 6. Four Little Mischiefs                  Rose Mulholland

 7. Girls and I                            Mrs. Molesworth

 8. Girl from America                     Mrs. L. T. Meade

 9. Grandmother Dear                       Mrs. Molesworth

10. Irvington Stories                     Mary Mapes Dodge

11. Little Lame Prince                         Mrs. Muloch

12. Little Susie Stories                  Mrs. H. Prentiss

13. Mrs. Over the Way               Julianna Horatio Ewing

14. Naughty Miss Bunny                     Rose Mulholland

15. Sweet Girl Graduate                   Mrs. L. T. Meade

16. School Queens                         Mrs. L. T. Meade

17. Sue, A Little Heroine                 Mrs. L. T. Meade

18. Wild Kitty                            Mrs. L. T. Meade

       *       *       *       *       *

_For sale by all Booksellers, or sent postpaid on receipt of 50c_




THE WONDER ISLAND BOYS

By ROGER T. FINLAY

_12mo, cloth. Price 75c each, postpaid._

Thrilling adventures on land and sea of two boys and a man cast upon an
island in the South Seas without food or weapons; their experience in
fashioning clothing, tools and weapons, and in overcoming nature and
subduing and civilizing savage tribes; covers a wide range of subjects.

 1. The Castaways
 2. Exploring the Island
 3. The Mysteries of the Caverns
 4. The Tribesmen
 5. The Capture and Pursuit
 6. The Conquest of the Savages
 7. Adventures on Strange Islands
 8. Treasures of the Islands


THE BOY GLOBE TROTTERS

By ELBERT FISHER

_12mo, cloth. Price 75c each, postpaid._

This is a series of form books relating the adventures of two boys who
made a trip around the world, working their way as they go. They meet
with various peoples having strange habits and customs, and their
adventures from a medium for the introduction of much instructive matter
relative to the character and industries of the cities and countries
through which they pass. A description is given of the native sports of
boys in each of the foreign countries through which they travel. The
books are illustrated by decorative head and end pieces for each
chapter, there being 36 original drawings in each book, all by the
author, and four striking halftones.

 1. From New York to the Golden Crate
 2. From San Francisco to Japan
 3. From Tokio to Bombay
 4. From India to the War Zone

       *       *       *       *       *

_For sale by all Booksellers, or sent postpaid on receipt of 75c_




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Printed from large, clear type on a superior quality of paper,
embellished with original illustrations by eminent artists, and bound in
a superior quality of book binders' cloth, ornamented with illustrated
covers, stamped in colors from unique and appropriate dies, each book
wrapped in a glazed paper wrapper printed in colors.


MOTOR BOAT BOYS SERIES

By Louis Arundel

1. The Motor Club's Cruise Down the Mississippi; or, The Dash
   for Dixie.

2. The Motor Club on the St. Lawrence River; or, Adventures
   Among the Thousand Islands.

3. The Motor Club on the Great Lakes; or, Exploring the Mystic
   Isle of Mackinac.

4. Motor Boat Boys Among the Florida Keys; or, The Struggle for
   the Leadership.

5. Motor Boat Boys Down the Coast; or, Through Storm and
   Stress.

6. Motor Boat Boys' River Chase.

THE BIRD BOYS SERIES

By John Luther Langworthy

1. The Bird Boys; or, The Young Sky Pilots' First Air Voyage.

2. The Bird Boys on the Wing; or, Aeroplane Chums in the Tropics.

3. The Bird Boys Among the Clouds; or, Young Aviators in a
   Wreck.

4. Bird Boys' Flight; or, A Hydroplane Round-up.

5. Bird Boys' Aeroplane Wonder; or, Young Aviators on a Cattle
   Ranch.

CANOE AND CAMPFIRE SERIES

By St. George Rathborne

1. Canoe Mates in Canada; or, Three Boys Afloat on the Saskatchewan.

2. Young Fur Takers; or, Traps and Trails in the Wilderness.

3. The House Boat Boys; or, Drifting Down to the Sunny South.

4. Chums in Dixie; or, The Strange Cruise in the Motor Boat.

5. Camp Mates in Michigan; or, With Pack and Paddle in the Pine
   Woods.

6. Rocky Mountain Boys; or, Camping in the Big Game Country.
       *       *       *       *       *

For sale by all booksellers, or sent postpaid on receipt of 75c




BOYS' COPYRIGHTED BOOKS

Printed from large, clear type on a superior quality of paper,
embellished with original illustrations by eminent artists, and bound in
a superior quality of book binders' cloth, ornamented with illustrated
covers, stamped in colors from unique and appropriate dies, each book
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       *       *       *       *       *

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  9 Captain Bayley's Heir
 10 Cat of Bubastes
 11 Col. Thorndyke's Secret
 12 Cornet of Horse, The
 13 Dragon and the Raven
 14 Facing Death
 15 Final Reckoning, A
 16 For Name and Fame
 17 For the Temple
 18 Friends, Though Divided
 19 Golden Canon
 20 In Freedom's Cause
 21 In the Reign of Terror
 22 In Times of Peril
 23 Jack Archer
 24 Lion of St. Mark
 25 Lion of the North
 26 Lost Heir, The
 27 Maori and Settler
 28 One of the 28th
 29 Orange and Green
 30 Out on the Pampas
 31 Queen's Cup, The
 32 Rujub, the Juggler
 33 St. George for England
 34 Sturdy and Strong
 35 Through the Fray
 36 True to the Old Flag
 37 Under Drake's Flag
 38 With Clive in India
 39 With Lee in Virginia
 40 With Wolfe in Canada
 41 Young Buglers, The
 42 Young Carthaginians
 43 Young Colonists, The
 44 Young Franc-Tireurs
 45 Young Midshipman

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+------------------------------------------------------------------+
|                                                                  |
| Transcriber's Note:                                              |
|                                                                  |
| Every effort has been made to replicate this text as             |
| faithfully as possible, including obsolete and variant           |
| spellings and other inconsistencies. Obvious                     |
| spelling/typographical and punctuation errors have been          |
| corrected after careful comparison with other occurrences        |
| within the text and consultation of external sources. Minor      |
| punctuation errors have been amended without note.               |
|                                                                  |
| Page 137: Incorrect pressure of 88 oz. for wind speed of 10      |
| mph changed to 8 oz.                                             |
|                                                                  |
| Page 146: Micron incorrectly printed as 1.25400, changed to      |
| 1/24500.                                                         |
|                                                                  |
| Page 178: Corrected table entry for 1-7/8, printed as 1/7-16.    |
|                                                                  |
| Alphabetic order errors in the glossary retained.                |
|                                                                  |
+------------------------------------------------------------------+





End of Project Gutenberg's Practical Mechanics for Boys, by J. S. Zerbe