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[Illustration: PATENT GRANTED TO THE AUTHOR]




                               INVENTING
                               FOR BOYS

                                  BY

                         A. FREDERICK COLLINS

                  INVENTOR OF THE WIRELESS TELEPHONE

                   _WITH NUMEROUS ILLUSTRATIONS AND
                               DIAGRAMS_

                            [Illustration]

                               NEW YORK
                      FREDERICK A. STOKES COMPANY
                              PUBLISHERS




  _Copyright, 1916, by_
  FREDERICK A. STOKES COMPANY

  _All rights reserved_




  TO
  JOHN ROLLER COLLINS
  A THINKER OF THOUGHTS
  NEW AND NOVEL




A WORD TO THE BOY


Every boy is a born inventor.

And since you are a boy it follows as the night the day that you have
your share of inventive ability and you ought to make good use of it.

To find out some new way of making or doing a thing--for this is what
inventing means--is the most fascinating game that I know of to take up
a fellow’s time and thought and energy.

You may say how about wireless, or star-gazing, or baseball, or
shooting, or chess, or any one of a dozen other pastimes and sports and
I shall be bound to admit that all of them are highly entertaining and
some of them instructive but inventing is all that the others are and
besides it is _constructive_ while they are not.

By constructive I mean that you take an idea that had its origin in
your brain and this vague, intangible conception, which takes up no
space, has no weight and is not bound by time, you build up step by
step of wood and steel and like materials until at last you have
created something out of nothing, or as nearly as it can be done.

To watch your invention grow, especially if you build it with your own
hands, from the time you make the first rough sketch of your idea
until it stands completed and in working order, gives you a wonderful
feeling of pride and satisfaction for you are the _creator_ of it and
this means that you are more than a mere boy, greater than an ordinary
man--that you are in very truth a _demi-god_.

These are the real pleasures of inventing but to make a success of it
you have to drop back to earth again and take up the mean, the sordid
part, and that is to try to make money out of it. And if you have an
invention of merit you will have to forget that you are a demi-god and
become a hard and fast mortal again or it will not be long before some
other body owns it lock, barrel and stock; and then you will have a
chance to start another idea rolling and to build up another invention.

In this book I have tried to point out to you not only how to invent,
but how to make money out of your invention as well, and so, I say unto
you, from the moment the big idea strikes you be as gentle as a dove
and as wise as a serpent, to the end that your days as an inventor may
be long and that any profits which may accrue from your invention will
be yours instead of some one’s else. And now may peace be with you.

  A. FREDERICK COLLINS.

  Lyndon Arms,
  524 Riverside Drive,
  New York City.




CONTENTS


  CHAPTER                                                           PAGE

  PREFACE                                                            vii

  I. GETTING AN IDEA                                                   1

   HOW TO GET AN IDEA

    The First Raw Idea.--Accidental Discoveries.--Thought
    out Ideas.--Reading up Your Subject.--Working
    out Ideas by Experiment.--Ideas for
    Inventions in General.--Ideas for Mechanical
    Inventions.--Ideas for Electrical Inventions.--Ideas
    for Electro-Mechanical Inventions.--Ideas
    for Chemical Inventions.--Ideas for Electro-Chemical
    Inventions.

   PROTECTING YOUR RAW IDEAS

  II. WORKING IT OUT ON PAPER                                         19

   TOOLS FOR MAKING SIMPLE DRAWINGS

   HOW TO MAKE SIMPLE WORKING DRAWINGS

   A SIMPLE WAY TO DRAW IN PERSPECTIVE

    How to Make Isometric Paper.--Drawing Tools
    you Need.

   HOW TO DRAW ISOMETRIC ELLIPSES

    An Easy, Rough Way and a Hard, Accurate Way.

   HOW TO SHADE DRAWINGS

   HOW TO MAKE ELECTRICAL SYMBOLS

   HOW TO READ ELECTRICAL DIAGRAMS

   SOME AIDS TO DRAWING

   MAKING CARDBOARD MODELS

  III. THE STATE OF THE ART                                           45

   WHAT IS MEANT BY THE STATE OF THE ART

   USE OF THE STATE OF THE ART

   HOW TO LEARN THE STATE OF THE ART

   HAVING A PATENT ATTORNEY LOOK IT UP

   HOW TO LOOK IT UP YOURSELF

   WHAT TO DO WHEN YOU FIND

    (a) There are no other improvements like yours.--(b)
    That there is a resemblance to yours.--(c)
    When others are exactly like yours.

  IV. HOW TO EXPERIMENT                                               58

   HOW TO EXPERIMENT WITH MACHINES

    Work, Energy and Power.--Work Against Friction.--Forms
    of Energy.

   MACHINES AND THE PRINCIPLES OF MACHINERY

   THE USES OF MACHINES

   THE SIX MECHANICAL POWERS

   COMPOUND MACHINES.--BOOKS

   HOW TO EXPERIMENT WITH ELECTRICITY

   FORMS OF ELECTRICITY

    Static Electricity.--Current Electricity.--Magnetism.--Radiation.

   YOUR ELECTRICAL EQUIPMENT.--BOOKS

   HOW TO EXPERIMENT WITH CHEMISTRY

   YOUR CHEMICAL EQUIPMENT.--BOOKS

   HOW TO EXPERIMENT WITH ELECTRO-CHEMISTRY

  V. MAKING A MODEL                                                   91

   KINDS OF MODELS

    Rough Models.--Scale Models.--Working
    Models.

   WAYS TO MAKE A MODEL

    Making a Model Yourself.--Having a Model
    Maker Make It.

   THE TOOLS YOU NEED

    The Vernier.--The Micrometer.--A and S Wire
    Gage.--Drill Press.--Screw Cutting Lathe.

   BUYING MATERIALS

   ABOUT MAKING PATTERNS

   CASTING IN BRASS AND IRON

  VI. HOW TO PATENT YOUR INVENTION                                   112

   WHAT A PATENT IS

   CHOOSING A PATENT ATTORNEY

   APPLYING FOR A PATENT YOURSELF

   APPLYING FOR A PATENT THROUGH A PATENT ATTORNEY

   WHAT YOU MAY PATENT

   LOOKING AHEAD

   WHAT A PATENT CONSISTS OF

    The Petition.--The Drawings.--The Specifications.--The
    Claims.--The Oath.

   WHILE YOUR PATENT IS PENDING

   INTERFERENCE

   WHEN YOUR PATENT IS GRANTED

   ABOUT PAPER PATENTS

  VII. MAKING YOUR INVENTION PAY                                     131

   HOW TO RAISE THE INITIAL FUNDS

   ABOUT AN INTEREST IN A PATENT

    Royalties, Shop Rights, etc.

   FORMING A PARTNERSHIP

   WHERE THE PROMOTER COMES IN

   WHAT A STOCK COMPANY IS

   HOW A STOCK COMPANY IS ORGANIZED

    The Fees of the State.--Outfit Needed.

   HOW A STOCK COMPANY IS OPERATED

   ABOUT RETAINING A LAWYER

  VIII. SOME HINTS OF MANUFACTURING                                  146

   PROBLEMS OF MANUFACTURING

    Farming out the Work.--Starting Your Own
    Shop.--Buying Machine Tools.--Buying the
    Stock.--Organizing a Shop Force.--The Stock
    Room.--The Finished Product.--Overhead
    Charges.

   WHERE YOUR PROFITS COME IN

  IX. PUTTING IT ON THE MARKET                                       166

   HOW BEST TO DO IT

    Agents Wanted.--The Mail Order Business.--A
    Series of Follow-Up Letters.--Selling Through
    Sales Agents.--Selling Direct from Factory to
    Consumer.--Selling Through the Trade.

   GETTING PUBLICITY

   ADVERTISING

  X. THINGS FOR YOU TO INVENT                                        180

   SOME LITTLE THINGS NEEDED

    For the Person.--For the House.--For the
    Farm.--For the Office.--For Fun.

   SOME BIG INVENTIONS NEEDED

    Safety First.--Automobiles.--Aviation.--Chemistry.--
    Electricity.--Electro-Chemistry.--Building.--Mining
    and Metallurgy.--Printing.--Moving Pictures.

   WHAT NOT TO INVENT

  XI. WHAT SOME INVENTIONS HAVE PAID                                 200

   A TOUR OF THE INVENTIVE WORLD

   LITTLE INVENTIONS

   SIMPLE INVENTIONS

   REAL INVENTIONS

   GREAT INVENTIONS

    The Steam Engine, Locomotive, and Steamboat.--The
    Telegraph.--The Perfecting Press.--The
    Sewing Machine.--The Ice Machine.--The
    Steel Process.--The Gas Engine.--The Dynamo
    and Motor.--The Air Brake.--The Telephone.--The
    Typewriter.--The Phonograph.--The Storage
    Battery.--The Snap-shot Camera.--The
    Steam Turbine.--The Automobile.--The Incandescent
    Light.--The Trolley Car.--The Electric
    Locomotive.--The Linotype.--Moving Pictures.--The
    Wireless Telegraph.--The Wireless
    Telephone.--The Aeroplane.

  XII. PROFITABLE INFORMATION                                        216

   DESIGN PATENTS

   ASSIGNMENTS

   CAVEATS

   PATENT OFFICE FEES

   TRADE MARKS

   COPYRIGHTS

   GOVERNMENT FEES FOR PATENTS AND LEAST CHARGES
   OF PATENT ATTORNEYS

   FOREIGN PATENTS

  APPENDICES                                                     229-252

  SOME WORDS AND TERMS USED IN THIS BOOK                         253-260

  INDEX                                                          261-270




ILLUSTRATIONS


                                                                    PAGE

  Patent granted to the author                            _Frontispiece_

  A popular idea of an inventive genius                                2

  Where the big idea really originates                                 3

  A model self-inking printing press                                   9

  A velocipede scroll saw with boring attachment                      10

  A standard single cylinder air pump                                 11

  A horizontal steam engine                                           12

  A fireless cooker                                                   13

  A loud speaking telephone largely used on ship-board                14

  A common electric bell                                              15

  An ordinary telegraph sounder                                       16

  A telautograph                                                      17

  The gyro compass of a ship                                          18

  A twelve inch rule                                                  19

  A pair of cheap compasses                                           19

  An isometric perspective drawing of a box                           20

  Top, side and end view of same                                      20

  Cross-section of same; drawing of hook                              21

  Side view of a steam engine                                         22

  End view of same                                                    23

  Top view of same                                                    24

  Cross-section of same                                               24

  The side valve shown in detail                                      25

  An isometric perspective drawing of a steam engine                  25

  A sheet of isometric drawing paper                                  26

  First step in isometric perspective drawing                         27

  The next step in isometric perspective drawing                      27

  A crank shaft drawn on isometric paper                              28

  A drawing board; a triangular scale                                 29

  A set of inexpensive drawing instruments; a protractor              30

  The position of the protractor on paper                             31

  The proportion of an isometric ellipse                              32

  How ellipses stand out in relief                                    33

  How an isometric ellipse is drawn                                   34

  Shading and lettering chart for drawings                            35

  Chart of electrical symbols                                     37, 38

  A simple wiring diagram                                             39

  Aids to drawing a manikin; proportions drawn on cross-section
  paper; trial positions of manikin                                40-42

  Cardboard model of a gyro engine                                    44

  The Official Gazette; Patent specifications; Index to Patents       53

  A lever of the first class; a pair of pliers                        63

  A lever of the second class; wire splicing clamps                   63

  A lever of the third class; a pair of sugar tongs                   64

  A bent lever                                                        65

  A compound lever                                                    65

  Wheel and axle                                                      66

  A train of wheels or wheel works                                    66

  A fixed pulley                                                      67

  An incline plane and one of its uses                                67

  A simple wedge; a printer’s quoin                                   68

  The theory of a screw; a screw clamp                                68

  Some useful mechanical movements                                 70-73

  A steady direct current; an interrupted direct current; a
  pulsating direct current; an alternating current; alternating
  current changed into an interrupted direct current;
  a periodic oscillating current; a sustained oscillating current  76-78

  Some useful electro-mechanical devices                           80-81

  An ammeter; a voltmeter                                             82

  A resistance box                                                    83

  Side and end view of a winding device                               84

  Making a ruby by chemistry; ruby boules as they come from
  the furnace; synthetic rubies after they are cut                    85

  Some useful chemical apparatus                                      87

  An electric furnace showing parts and in operation               88-89

  Rough model of an electric motor drive for a locomotive             92

  A scale model of an aeroplane                                       93

  A toy helicopter                                                    94

  A working model of a locomotive                                     95

  Some useful jewelers’ and machinists’ tools                        101

  A small hand drill press                                           102

  A foot power screw-cutting lathe                                   103

  A vernier for accurate measurement                                 103

  A micrometer                                                       105

  A standard wire gage                                               106

  Useful stock materials made by automatic machinery                 107

  A standard for a telegraph sounder                                 109

  Pouring a mould                                                    110

  Rules of Practice of the Patent Office                             116

  A page of drawings                                                 121

  Specification of one of Mr. Collins’ patents                       123

  The Claims of the same patent                                      123

  The U. S. Patent Office, Washington, D. C.                         129

  Certificate of Incorporation                                       139

  Stock certificate                                                  141

  A seal press                                                       142

  A gas furnace                                                      150

  A grinder and polisher                                             151

  A plain lathe for turning metal with hand tools                    152

  An engine lathe                                                    153

  Pillar type of power drill                                         154

  A planer for surfacing metal work                                  154

  A shaper for shaping up metal work                                 155

  A universal milling machine                                        156

  A jig saw                                                          157

  A band saw                                                         158

  A time stamp                                                       162

  A high frequency machine                                           163

  From manufacturer to canvasser, to consumer                        167

  From manufacturer to order agent, to consumer                      169

  From manufacturer to his agent, to consumer                        172

  Selling direct from factory to consumer                            173

  Selling through the trade                                          174

  Old style and improved tooth brush                                 182

  The old and the new way in sweeping carpets                        183

  A labor saving painting machine                                    184

  A quick figuring and bookkeeping machine                           185

  A rubber dagger                                                    186

  Bumping-the-bumps                                                  187

  A novel, life-saving gun                                           188

  The Owen magnetic clutch                                           189

  A gyro stabilizer                                                  189

  A liquid air machine                                               190

  The cheapest form of light                                         190

  A tube system of electric light                                    191

  The high tension electric generator                                192

  Cutting steel girders with oxy-acetylene                           193

  Apparatus for prevention of mine disasters                         194

  A steel plate engraving machine                                    195

  An attempt to improve the movies                                   196

  Tesla’s tower at Wardencliffe, L. I.                               197

  A perpetual motion machine                                         198

  Perpetual motion as seen by a patent attorney                      199

  The first telephone                                                205

  The first typewriter                                               206

  The first phonograph                                               207

  The first incandescent light                                       210

  Collins wireless telephone                                         214

  Design patent                                                      216

  A registered trade mark                                            220

  Application blank for copyright of a book                      222-223

  Cross-section of gear                                              238

  The four chief thermometric scales                                 251




INVENTING FOR BOYS




CHAPTER I

GETTING AN IDEA


Almost every one has had, at some time or other an _idea_ for a new
_invention_ or of how some old _device_ could be improved.

To get an original idea for an invention is in itself a mark of genius,
but it is not enough to make it a success and if you do not know how to
develop it you are almost certain to give up before you have completed
it.

And to give up a good idea and then find that some one else has thought
of the same thing later, worked it up and made money out of it gives a
fellow a most uncomfortable feeling about what might have been.

Now my purpose is not to tell you _what_ to invent as much as it is to
tell you _how_ to invent and, if when you get an idea that you believe
worth while you will follow it up step by step as I have outlined in
this book you will at least save yourself time, worry and money and you
stand a chance of winning fame, glory, and a bank account.


~How to Get an Idea.--~There is only one way to invent a new thing or
to make an improvement on something that has already been invented and
that is to get an idea.

[Illustration: FIG. 1. A POPULAR IDEA OF AN INVENTIVE GENIUS]

And what, you may wonder, is an idea? It is easy to say that it is a
_notion_ that comes into your head, or a thought that springs into your
mind. But I doubt if even a _psychologist_ could explain just what an
idea is or how one originates in the mind any more than a _biologist_
could tell how the germ of life is retained in a seed and how it grows
when it is planted.

One good thing about an idea, though, is that we don’t have to know
what the mysterious thing is or how it springs into being in the mind.
In this way an idea is very much like electricity--we don’t know
exactly what it is but we do know a good deal about how it works and
this is enough for our present purpose.


~The First Raw Idea.--~There are several ways by which you may get an
idea for an invention but in any case the first raw idea, or _inductive
discovery_, as it is called in _philosophy_, must and does come from
something outside the mind, something that you have seen, heard,
smelled, tasted or felt, and when your mind is in the right condition
to receive an idea of this kind you will know it when it comes and
grasp it very quickly, that is if you are a real inventor.

[Illustration: FIG. 2. WHERE THE BIG IDEA REALLY ORIGINATES]

There are many kinds of raw, or original ideas and they show themselves
in various ways. You may get a very vague idea of an invention, or
of an improvement, or it may be a clean cut one on the jump; it may
be a very valuable idea or it may be a wholly worthless one, but it
is generally easy after you get one to enlarge upon it, as we shall
presently see, and to build up in the mind’s eye a structure so
that you can guess pretty nearly whether you will have a palace, an
architectural monstrosity or a chicken-coop when it is done.

A first, or raw idea may come to a fellow, who is on inventing bent,
in any one of several ways but chiefly when (1) he is conjuring up
in his mind something which he has seen or heard; (2) when something
happens by accident which shows him an effect or a result that is new,
and (3) when he is looking at or working on some device or machine; and
this last way is the one that is most productive of ideas for useful
improvements.

As an example of getting an idea behold a young man rocking in a chair
with closed eyes; he is thinking of nothing in particular but of a
good many things quite vaguely. A thought of his sister packing her
trunk--in the way a woman usually packs a trunk--comes into his mind
and then an idea strikes him that it would be a good scheme for a trunk
to have drawers in it like a bureau. The result of this raw idea is the
_wardrobe trunk_ as we know it to-day.


~Accidental Discoveries.--~Once in a long while some one hits upon an
invention purely by accident.

A good illustration which covers the point was the discovery of
_vulcanized rubber_. The story goes that Charles Goodyear happened to
drop some crude rubber and sulphur on a hot stove at the same time with
the result that it was made much stronger and more elastic than before.

Experiment showed that the vulcanized rubber could be made as soft or
as hard as desired by using more or less sulphur and applying more or
less heat. From this discovery of Goodyear’s has sprung the gigantic
rubber industry of to-day.

Discoveries of this kind were often made in the early days of invention
but the principles which underlie all of the sciences are now so well
known that invention itself has been brought down to a scientific
basis; and instead of inventors being long-haired, dreaming Micawbers
they are generally men of education and genius too, trained along the
lines they are working in and who look like clean-cut business men;
and if they are successful inventors you may depend upon it they are
business men.

When I say that they are men of learning I do not mean that it takes
a college professor to be a big inventor; indeed very few college
professors have the genius to be inventors and too many inventors have
too little knowledge along the line in which they are working. Of the
two genius is the greatest for it is bred in the bone while any one can
educate himself.

To make the point clear here are three famous men of genius and who
were largely self-taught.

Faraday who made the dynamo and motor possible was a poor, uneducated
boy with a burning thirst for knowledge when he was apprenticed to
Davy at the Royal Institution in London. Edison had about as little
schooling as the law allows, but he taught himself science and he now
stands head and shoulders above all the rest of the great inventors.
And Marconi, a young fellow of 23, invented the wireless telegraph
while the greatest scientists of the world could not do it until he
showed them how.


~Thought Out Ideas.--~There are very few inventions which are complete
when the first idea of it comes into the mind, but instead nearly all
of them require thinking out, or _deductive proof_ as it is called in
philosophy.

This second process of thinking consists of turning the raw idea over
and over in your mind so that you can judge whether it is good or not,
how it will work out and other things about it, and to do this you must
know as many of the facts relating to it as you can and when you have
these all clear and catalogued in your mind your idea then takes on the
aspect of an invention.

The two usual ways to get the needed facts are (1) to read up on the
subject, and (2) to experiment along the line of your idea. Of course
if it is your regular work that has called forth your first idea it is
quite likely you will have all of the facts you need to go ahead and
work the thing out; but if your idea is about a device, or a machine,
or a compound you know nothing of your best plan is to read up on the
subject and follow up your reading by making a number of experiments.


~Reading up Your Subject.--~In this day of public libraries it is easy
to get books on any subject unless it is one on sunsets and sunsets
don’t count in inventing--in fact nothing counts except the big idea,
a shop or a laboratory to develop it in and burning the midnight
incandescent light.

It doesn’t matter very much what invention you are working on you ought
to read a _first book_ on _physics_ and one on _chemistry_ and what’s
more you should study them if you expect to ever invent anything of
magnitude.

A book on physics tells all you need to know in the beginning about
matter, force, motion, the principles of machines, the mechanics of
liquids and gases, electricity and magnetism, sound, heat and light.

Suppose you have an idea for an electrical device, if you will read the
chapters on electricity and magnetism in your book of _physics_ you
will learn what you ought to know first about these subjects and then
if you need to go deeper you can get a more advanced book.

A book of the elements of chemistry tells about gases, acids, alkalies
and metals and of their chemical changes, and you will find a little
knowledge of chemistry of considerable use in working out many ideas.
There are many books of physics and chemistry but _Avery’s Elements
of Physics_ published by the American Book Company of New York, and
_Remsen’s Elements of Chemistry_ published by Henry Holt and Company of
New York are good books for a beginner to read.


~Working Out Ideas by Experiment.--~Though you may think long and hard
and read everything you can find that has a bearing on your great idea,
you will soon reach a point where you feel you would like to try it
out, that is to build it up in reality so that you can see if it will
do the work you want it to do or if it won’t do the work where the
trouble comes in.

Generally speaking if it is a mechanical or an electro-mechanical
scheme you begin by drawing this brain-child of yours on paper and then
you make a model, or try to, and you add to it, take away from it, tear
it down sometimes and at others you scrap it and build an entirely new
one.

But usually it is some one part that needs patience and effort and
skill put upon it and as you try out idea after idea, plan after plan
and scheme after scheme you are not only almost sure to find just what
you are looking for but very often experimental work will lead you to
fresh ideas for other and even more important improvements.

Another curious thing I have found about experimenting is this: you may
start out on a certain line and find that the result you want is so
hard to get it seems hopeless to go ahead. Now if you quit it is all
off but if you go on and on trying everything you can think of, keeping
up your belief that the thing you are striving for must come and in
your own ability to do that which you want to do, after long hours,
or days, or weeks of constant work the result will come to you like a
flash and just as though the guardian angel of invention hovered over
you and put the desired thing right into your mind and hand. The moral
is that everything comes to the inventor who keeps on experimenting
and does not give up.


~Ideas for Inventions in General.--~Inventions may be divided into
three general classes and these are (1) _mechanical_, (2) _electrical_
and (3) _chemical_; and there are combinations of these classes as (a)
_electro-mechanical_ and (b) _electro-chemical_ inventions and your
idea may come under the head of any one of them.

[Illustration: FIG. 3. A MODEL SELF-INKING PRINTING PRESS]


~Ideas for Mechanical Inventions.--~Inventions of a mechanical kind
include nearly everything in the broad domain of physics but the term
_mechanical inventions_ is applied especially to devices that are
worked by means of pendulums, springs, weights, levers, wheels and
axles, pulleys and inclined planes, screws and pistons and which have
to do with force and motion.

To work out an idea for a mechanical device if the latter is a fairly
simple one, as a printing press, see Fig. 3, or a scroll saw, see Fig.
4, should not be a very hard thing to do because all of the parts
can be easily seen and if you add a few parts to it and it does not
work the fault can be readily picked and the part that is causing the
trouble can be redesigned and changed until the whole device is made
operative.

[Illustration: FIG. 4. A VELOCIPEDE SCROLL SAW WITH BORING ATTACHMENT]

Of course if the machine is a more complicated affair in which there
are pistons, valves and the like as in an air-pump, see Fig. 5, or an
ordinary engine, see Fig. 6, it is liable to develop internal--or
perhaps infernal would be more fitting--troubles that are sometimes
very pertinacious and hard to overcome.

[Illustration: FIG. 5. A STANDARD SINGLE CYLINDER AIR PUMP]

The easiest and best paying way to begin a career of inventing is to
hit on an idea to improve some simple device that either makes for
safety or for saving, for convenience or for lessening mental or manual
labor. But if you should happen to get an idea for something big and
hard don’t give it the go-by, but follow it up along the lines which I
have indicated in this book and you will stand a pretty good chance of
finally working it out to a successful conclusion.


~Ideas for Electrical Inventions.--~Ideas for inventions in which
electricity and magnetism are used are generally harder to work out
than those of a purely mechanical kind for the reason that the cause
in the first case which produces the result you want cannot be seen,
whereas the cause in the second case which sets up the effect you want
is always visible.

But electrical inventions are like mechanical inventions in that they
may be very simple, such as passing a current through the heating
element of an electric cooker as shown in Fig. 7, or it may be quite a
complex piece of apparatus as for instance a loud speaking telephone
for use on ship-board as shown in Fig. 8.

[Illustration: FIG. 6. A HORIZONTAL STEAM ENGINE]

Where an electric current is used for some simple device a thorough
knowledge of electricity may not be necessary but if your invention
requires that a _low voltage_ current be changed into _high frequency
oscillations_ which are in turn varied by the voice and these
oscillations are sent out from an _aerial wire_, all of which is done
in a wireless telephone, I should say that you ought to have a pretty
fair understanding of the theory of electricity before you begin your
experiments--that is if you expect to develop your invention into an
apparatus of utility and hence of worth.


~Ideas for Electro-Mechanical Inventions.--~There are many devices that
are partly electrical and partly mechanical, the _operation_ of the one
_actuating_ the other and the other way about.

[Illustration: FIG. 7. A FIRELESS COOKER. THE HEAT IS WHERE YOU WANT IT]

The electric bell, see Fig. 9, and the telegraph sounder, see Fig.
10, are types of simple electro-mechanical devices, while the
telautograph, see Fig. 11, and the electrical gyroscopic compass for
use on ship-board, see Fig. 12, are examples of the more complex
electro-mechanical devices.

To work out an idea by bringing both mechanics and electricity to bear
in the same device often makes the work much easier for sometimes the
armature of an _electromagnet_ or the plunger of a _solenoid_ will
operate to a better advantage than a combination of levers. But to use
mechanics and electricity in the same device you must of course have a
knowledge of them both.


~Ideas for Chemical Inventions.--~There is another class of ideas which
require neither mechanics nor electricity for their working out. They
are chemical compounds.

[Illustration: FIG. 8. A LOUD SPEAKING TELEPHONE LARGELY USED ON
SHIP-BOARD]

Suppose an idea comes to you to make a chemical solution for erasing
ink, or to make a new high explosive. While the idea might be a good
one you would have a long road to travel if you began experimenting and
had no knowledge of chemistry and your road in the latter case would
probably be straight up.

Trying out chemical compounds without knowing something of the
reactions they produce is far more wasteful of time and money than
puttering around with mechanical and electrical devices, especially
when one’s line of business is selling ribbons, and besides it’s more
or less dangerous too.

Should you get an idea for making an explosive more powerful than any
yet invented, either _dish_ the idea or pave the way by taking a course
in advanced chemistry and even then your idea is liable to perish with
you. Better let the Maxims or the du Ponts do it.

[Illustration: FIG. 9. A COMMON ELECTRIC BELL]


~Ideas for Electrochemical Inventions.--~Just as there are ideas that
call for the use of mechanics and electricity in a single device
so there are ideas for processes that combine both chemistry and
electricity.

The action of a common dry cell is electrochemical and so is
electroplating. But there are a large number of chemicals and chemical
substances that are produced by electricity such as _nitric acid_
from the air, _calcium carbide_ from which _acetylene gas_ is made,
_carborundum_ which is used as an _abrasive_ in the place of emery, and
then there is the _electrolytic_ refining of copper, the manufacture of
_aluminum_, besides a whole string of other electrochemical inventions.

[Illustration: FIG. 10. AN ORDINARY TELEGRAPH SOUNDER]

While it is quite safe to work along electrochemical lines still it
takes a considerable amount of technical knowledge in these days to
invent anything that the kultured German scientists haven’t thought of
and worked out.


~Protecting your Raw Ideas.--~Just as soon as you have an idea for an
invention write as clear a description of it as you can, read it to the
members of your family, have them sign it and file it away as this is
a record you may have to produce sometime in the future to prove your
_priority_, that is that you were the first in time to conceive the
idea.

As soon as you have your idea all thought out and have made a drawing,
an experiment, a cardboard or other model, in fact anything that will
show what it will do, at least to some extent, and so prove that you
have really made a new invention, invite two or three of your trusted
friends to see it.

[Illustration: FIG. 11. A TELAUTOGRAPH. A TELEGRAPH FOR REPRODUCING
WRITING AT A DISTANCE]

Having shown, explained and enthused over it have them go with you to
a _notary public_ and sign a statement to the effect that they have
seen it; then have him put his signature and his seal on it. You have
two years from the date you first showed it to develop and file an
application for a patent on it but should you fail to do this within
the above time limit any one else can take up your idea, if they know
of it, work it up and get a patent on it.

Finally keep a note book and write down every thought you have about
your invention, and every experiment you make in good black ink; draw
pictures and diagrams and make photographs if possible of your work
as you go along and put them in your book with the dates on them.
This kind of a record will furnish you with what patent attorneys
call the _evidence of conception_, and which will prove very useful
in establishing your prior rights if you should ever get into an
_infringement_ suit.

[Illustration: FIG. 12. THE GYRO COMPASS OF A SHIP. A GYROSCOPE TAKES
THE PLACE OF THE MAGNETIC NEEDLE]




CHAPTER II

WORKING IT OUT ON PAPER


The next step after, and sometimes even before, you have thought out
your great idea is to make a drawing of the invention it represents.

Nearly every one can do a little _free hand drawing_ and this is a
good way to make rough sketches to aid the mind in further developing
thought.

But if you can make a simple _working drawing_ of your device, that
is a picture in which all of the parts are drawn in proportion, or to
_scale_ as it is called, the whole thing will stand out clearly before
you and you can see where it is wrong and make the needed changes on
paper before you try to build a model.

[Illustration: FIG. 13. A TWELVE INCH RULE]

[Illustration: FIG. 14. A PAIR OF CHEAP COMPASSES]


~Tools for Making Simple Drawings.--~To make simple working drawings,
or _mechanical drawings_ as they are called, all the tools you need are
a good, straight 12-inch rule, as shown in Fig. 13, _compasses_ as
shown in Fig. 14, a medium hard lead pencil, a rubber eraser and some
smooth white paper.


~How to Make Simple Working Drawings.--~At A in Fig. 15 is shown a
drawing in perspective, that is as it would look to the eye, of a
_rectangular_ box, while B is a top view, C is a side view and D is an
end view of the same box; of course the bottom and the other end and
side cannot be seen but you can imagine pretty well that they are there
if you try to.

[Illustration: FIG. 15A. AN ISOMETRIC PERSPECTIVE DRAWING OF A BOX]

[Illustration: FIG. 15. B, A TOP PLAN VIEW OF THE BOX. C, A SIDE PLAN
VIEW OF THE BOX. D, AN END PLAN VIEW OF THE BOX]

To show the top, bottom, sides and ends of a box, or other device, you
don’t need to draw out the whole thing in perspective but you can make
a flat, or plan view of each part as shown at B, C and D in Fig. 15,
that is an outline drawing shown as though you were looking squarely at
it in the center and with the measurements marked upon it.

If now you will make a set of these working drawings of, say, a box
and draw each part to _scale_, that is measured off in proportion, as
shown in B, C and D, and saw out of a board the top, bottom, sides and
ends and nail them together you will have a box like that shown in
perspective at A.

[Illustration: FIG. 15. E, A CROSS SECTION VIEW OF THE BOX. F, DETAILED
DRAWING OF THE HOOK]

Plan views are easy to draw because they are formed of horizontal and
vertical lines, and wheels are shown as true circles. After making your
plan views, though, the safest way is to make a perspective drawing to
the same scale for when you are looking at a square object as it really
is it always appears larger than the plan views would indicate. But
this is ahead of the story.

Now suppose you wanted to show how the box would look if it was sawed
lengthwise through the middle. You simply make a _cross-section_ view
of it as shown at E and any one who knows how to read drawings will
understand it. To show the hook on the front of the box more clearly it
can be drawn separately as at F and this is called a _detail drawing_.

Exactly in the same way any device, apparatus or machine can be shown
by top, side and end views and by _cross-section_ and detail drawings.

[Illustration: FIG. 16. A SIDE VIEW OF A STEAM ENGINE]

Just to see how something a little more complicated would work out on
paper, let’s take the cylinder and steam chest of a steam engine. First
draw a side view of these parts as shown in Fig. 16.

As the steam chest is a rectangle and every side of it is flat it can
be shaded by drawing fine parallel lines spaced equally apart. The
cylinder, pipes and rods are round, or rather cylindrical, and to get
this effect these parts should be shaded with parallel lines drawn
close together beginning at the top and bottom and making them ever
farther apart as you get toward the middle and this will give it a
rounded appearance.

Next draw the end view of the cylinder and steam-chest. Since the
cylinder has been given a diameter of 3¼ inches in the side view, of
course it must have the same diameter in the end view as shown in Fig.
17.

[Illustration: FIG. 17. AN END VIEW OF A STEAM ENGINE]

By looking again at Fig. 16 you will see that the steam chest is 4½
inches long and that it is 2½ inches high but it is in the end view
Fig. 17, that the width of it is shown. The end of the steam chest is
shaded with straight parallel evenly spaced lines and the cylinder
head is shaded with _concentric circles_, that is with circles equally
spaced apart and having the same center.

[Illustration: FIG. 18. A TOP VIEW OF A STEAM ENGINE]

In this and many other cases a side view and an end view give all the
outside dimensions needed but sometimes a top view must also be made,
and this is shown in Fig. 18.

[Illustration: FIG. 19. A CROSS-SECTION OF A STEAM ENGINE]

While all of these views show the outside of the steam chest and the
cylinder they give no hint as to how the inside is made. Suppose you
had invented the steam engine of course you would know how the inside
should be made and so you make a cross-sectional drawing of the parts
as shown at Fig. 19, and then the construction and even the operation
of the engine looms up as though you had turned a searchlight on it.

[Illustration: FIG. 20. THE SIDE VALVE SHOWN IN DETAIL]

That is all of it will be clear except perhaps the slide valve and this
is where a detailed drawing comes in to show a small part, or a part
that is hard to understand by looking at the side, end and top views.
The slide valve, see Fig. 20, is drawn in detail and the picture is
made large and bold. The slide valve is made of a cast piece of metal
hollowed out. It and the completed steam chest and cylinder are both
drawn in _perspective_, that is just as the eye would see them if they
were actually made of metal. The latter is shown in Fig. 21.

[Illustration: FIG. 21. AN ISOMETRIC PERSPECTIVE DRAWING OF A STEAM
ENGINE]


~A Simple Way to Draw in Perspective.--~Did I hear you ask how you can
make a drawing in perspective? List and I will tell you the simplest
way--a way so that you do it the first time you try.

Buy a quire of _isometric_ (pronounced i-so-met´ric) _cross-section
paper_ 6 by 9 inches, at a cost of 15 cents, of any dealer in
drawing materials. This paper is lined in faint colored ink in three
directions, as shown in Fig. 22, and which represent length, breadth
and thickness.

[Illustration: FIG. 22. A SHEET OF ISOMETRIC DRAWING PAPER. THE REAL
SHEETS ARE PRINTED IN NEUTRAL TINTS, THAT IS, COLORS WHICH DO NOT
INTERFERE WITH THE DRAWING]

Now _isometric_ comes from _iso_ which means _equal_ and _metric_ which
means _measure_, so isometric means _equal measure_ and the three lines
used in isometric perspective are at equal distances from each other.
The lines which cross the vertical lines on isometric cross-section
paper are 30 degrees from the base, or horizontal line and the vertical
line is, of course, 90 degrees from the horizontal as shown in Fig.
23. Having everything at hand suppose you try to draw a square frame.
Begin by making the first upright and you will see by looking at Fig.
23 that all you have to do is to draw three vertical lines and join
the top and bottom by marking over the 30 degree lines. This done draw
three more uprights in the same way and when you have these on paper it
is easy to put beams on top or struts between them as shown at Fig. 24.

[Illustration: FIG. 23. FIRST STEP IN ISOMETRIC PERSPECTIVE DRAWING]

As all the lines are of equal measure you can mark on the exact
dimensions as shown in many of the isometric perspective drawings in
this book. For a drawing of some device, or of a whole machine, to
give to some mechanic to make for you the better way is to hand him a
perspective drawing together with the top, side and end views, rather
than the latter views alone, and then he will not need to figure out
how they are put together.

[Illustration: FIG. 24. THE NEXT STEP IN ISOMETRIC PERSPECTIVE DRAWING]

To show to a better advantage how isometric perspective works out look
at Fig. 25 and you will see how the bearings of a crankshaft of a four
cylinder gas engine stand out in a vertical line, up and down and in
a horizontal line right and left as though they were real and made in
three dimensions.

[Illustration: FIG. 25. A CRANK SHAFT DRAWN ON ISOMETRIC PAPER]


~How to Make Isometric Paper.--~To make isometric perspective drawings
you can get along without the cross-section paper described above
though this is the easiest and most accurate way to get results.

But you can make these drawings on any kind of paper if you know how to
use a _protractor_ and measure of 30 degrees. To do it right you should
have some drawing tools and if you are an inventor you should have them
anyway.


~Drawing Tools You Need.--~For making drawings of any kind you should
by all means have a _drawing-board_ as shown at A in Fig. 26. As a
drawing board must be perfectly square and made so that it cannot warp
it is better to buy one of a dealer in drawing materials.

[Illustration: FIG. 26A. A DRAWING BOARD]

A good board is built up of thoroughly seasoned strips of white pine
glued together and fitted with end ledges; a small board say 12 by 17
inches on the sides can be bought for 50 cents or a little more and it
will serve you well. A 12 inch _triangular boxwood architect’s scale_
is shown at B in Fig. 26 and is much handier to use than a common rule.

[Illustration: FIG. 26B. A TRIANGULAR SCALE]

A beginner’s set of drawing instruments consisting of _compasses_, with
pen and pencil points, a _ruling_ pen and a box of leads all in a nice
pocket case, as shown at C, Fig. 26, can be bought for $1.25 and these
compasses are easier to handle than the one shown in Fig. 14.

[Illustration: FIG. 26C. A SET OF INEXPENSIVE DRAWING INSTRUMENTS]

But the chief instrument you need is a _protractor_, as shown at D,
Fig. 26. This is a _semicircle_ of brass, or of German silver, 3¾ or
4½ inches in diameter and costs 10 cents or 40 cents, according to the
size and metal it is made of.

[Illustration: FIG. 26D. A PROTRACTOR FOR MEASURING CIRCLES AND ANGLES
BY DEGREES]

A protractor, as you may or may not know, is used to lay off _angles_
and to measure _angles_ in _degrees_. The curved part or scale of the
protractor is divided into 180 degrees since there are 360 degrees in
a circle. The figures start at both corners with 0 so that an angle of
any number of degrees right or left can be marked off. Now the lines
formed by marking off angles of 30 degrees are the only ones you will
have to make for isometric perspective. To do this fasten a sheet of
paper to your drawing board with thumb tacks at each corner and draw
a straight line across the paper near the bottom. Put your protractor
on the edge of the paper and the pencil line exactly as shown in Fig.
27; lay your rule so that its edge crosses the straight part of the
protractor at the middle, marked A in the drawing and also on the line
of the scale of the protractor marked 30 degrees and then draw a line
on the paper along the edge of your rule.

[Illustration: FIG. 27. THE POSITION OF THE PROTRACTOR ON PAPER]

This done place the protractor on the opposite and left hand edge of
the paper and the horizontal line and lay your rule with its edge
crossing the middle of the straight part of the protractor as before
and on the 30 degree line of the scale and so that when you draw the
line it will cross the other 30 degree line as shown in Fig. 27.

If now you draw another line at 90 degrees, that is vertically, between
the two crossed lines, also as shown in Fig. 27, each of the three
lines will be exactly the same distance apart in degrees. You can go
ahead now and draw lines ⅛ inch apart parallel with each of the three
lines and you will have a sheet of isometric cross section paper of
your own making.


~How to Draw Isometric Ellipses.--~_An Easy, Rough Way._--There is
just one more little thing you should know about making isometric
perspectives and that is how to draw disks, wheels and anything else
that is circular in form so that they will look right and be right.

[Illustration: FIG. 28A. THE PROPORTION OF AN ISOMETRIC ELLIPSE]

In isometric perspective everything that is round in reality is drawn
in the shape of an _ellipse_, that is a closed curve that is longer
than it is wide as shown at A in Fig. 28; there are different shaped
ellipses but there is only one used for isometric drawing and this is
always in the ratio of 1¼ to 2; that is if an ellipse is 2 inches long
it will be 1¼ inches wide; an ellipse 4 inches long will be 2½ inches
wide and so on.

An easy, though rough way to draw an isometric ellipse is to make
a line as long as the diameter of the disk or wheel you intend to
represent; draw another line which is the width of the ellipse through
the center and at right angles across it, see A again and then draw the
curved line around the end of them free hand.

[Illustration: FIG. 28B. HOW ELLIPSES STAND OUT IN RELIEF]

How these ellipses are made to appear as if they were set either in a
vertical or a horizontal position and at right angles to each other is
shown at B in Fig. 28. The _axis_, that is the spindle, or shaft on
which the disk, or wheel, is mounted, must always follow the 30 degree
line running at right angles to the edge of the board or whatever it
is supposed to be fastened to or goes through; and the thickness of the
disk or wheel is always shown on the same sides as the thickness of the
board or other part on which it is mounted, all of which is brought out
clearly at B in Fig. 28.


~How to Draw an Isometric Ellipse.--~_A Harder but More Accurate
Way._--Begin by drawing a straight line as long as you want the longest
axis of your ellipse to be, as shown at A B, Fig. 29. Divide this line
into four equal parts. Now take your compasses and with the needle at
the center of the line O draw a circle having the line as its diameter.

[Illustration: FIG. 29. HOW AN ISOMETRIC ELLIPSE IS DRAWN]

Next start at A with your dividers and divide the whole circle into ten
equal parts and then take your rule and draw a line from the point C on
the circle through the point G on the diameter and _produce_, or extend
it to the bottom of the circle; draw a line from D through G and extend
it to the top of the circle; draw a line from E through H and extend
it to the bottom of the circle when it will intersect the line C G at
the point J; and finally draw a line from F through H to the top of the
circle which will intersect the line D G at I.

Take your compasses and using G as a center draw the arc K A L; then
using H as a center draw the opposite arc M B N; using the point J as a
center, draw the arc K M so that its ends will meet the upper ones of
the end arcs perfectly; using the point I as a center draw the fourth
and last arc L N when the ellipse is completed.

When making isometric ellipses much care must be taken to make all
the points and draw all the lines with the greatest accuracy as the
slightest error will distort the whole thing.


~How to Shade Drawings.--~Besides the few hints for shading perspective
drawings which I have given above there are certain ways to shade
cross-sections and elevations to show whether it is made of metal,
glass, wood, liquid, cork, carbon, insulation or other materials. There
are also different kinds of shading to show fine and coarse fabrics and
the various colors.

[Illustration: FIG. 30. A SHADING AND LETTERING CHART FOR DRAWINGS]

The patent office has prepared a chart showing the shading that should
be used to represent the different materials and colors and these are
reproduced in Fig. 30. The letters of the alphabet both _upper_ and
_lower case_, as the capitals and little letters are called, which
are used by mechanical draftsmen are also shown in Fig. 30. As these
letters and figures are clear, easy to make and are preferred by the
patent office they are good ones for you to use.


~How to Make Electrical Symbols.--~In making drawings, either for
yourself or for the patent office, of electrical apparatus to show
how it is connected up you do not need to draw out a plan view or a
perspective of each part but you can make what are called _symbols_.

Symbols are simply a few lines or signs that stand for or represent
a certain piece of apparatus; as an illustration suppose you want to
show a dry cell, all you need to do is to make a couple of parallel
lines, one shorter and heavier than the other like this:

[Illustration: cell]

and if you want to show a battery you make as many pairs of parallel
lines as there are cells in this fashion:

[Illustration: battery]

And just so with every separate piece of electrical apparatus, and all
of them are shown at A and B in Fig. 31.

[Illustration: FIG. 31A. A CHART OF ELECTRICAL SYMBOLS]

[Illustration: FIG. 31B. A CHART OF ELECTRICAL SYMBOLS]


~How to Read Electrical Diagrams.--~From the plates of symbols given
at A and B in Fig. 31, you will see that the symbol for a battery is
a pair of parallel lines as shown above, that the symbol for a motor
is made in this fashion:

[Illustration: motor]

and that a switch is made like this:

[Illustration: switch]

now if you want to show a battery, a motor and a switch wired
together all you have to do is to join the symbols with lines as shown
at C in Fig. 31 and you will have what is called a diagram.

You can _read_ a diagram, that is understand how it is connected up, in
an instant for you can see at a glance how the wires run. Because the
wiring is shown so simply and clearly diagrams of this kind are usually
called _wiring diagrams_.

[Illustration: FIG. 31C. A SIMPLE WIRING DIAGRAM]

In drawing wiring diagrams try to place each symbol in such a position
that the connecting lines which represent the wires cross each other as
seldom as possible, otherwise your diagram will be confused and it will
be hard to follow out the circuits.


~Some Aids to Drawing.--~The following aid to drawing and designing was
published in the _English Mechanic_ and you will find it very helpful
if your invention has to do with an automobile, aeroplane, or any large
machine which is used or actuated by a person.

[Illustration: FIG. 32A. THE DIMENSIONS OF A MANIKIN]

Make a manikin, that is a little jointed figure of a man as shown at A
in Fig. 32. The figure can be made to any scale but 1 inch to the foot
which is ⅙ full size is a good ratio to make it but it must of course
be made to the same scale as the machine you are drawing.

To get the right proportions rule a sheet of paper a couple of inches
wide and about 8 inches long so that the divisions will be ¹/₁₂ inch
square and draw on this the different parts of the manikin as shown at
B in Fig. 32. Now since every ¹/₁₂ inch on the paper is equal to 1 inch
for a man 6 feet tall your manikin will be 6 inches high when it is
jointed and complete.

[Illustration: FIG. 32B. THE PROPORTIONS OF A MANIKIN DRAWN ON
CROSS-SECTION PAPER]

The figure can be made of cardboard if it is to be used only a few
times but thin wood, celluloid or hard rubber, or sheet tin, brass or
copper will make a much more substantial one. Whatever the material
that is used the edges of each part should be filed smooth; and when
you rivet the parts together to make the joints the latter should work
smooth and yet stiff enough so that the parts will stay in whatever
position you place them.

[Illustration: FIG. 32C. A TRIAL POSITION OF THE MANIKIN]

When you lay the manikin on your drawing you can see whether or not the
levers are in the right places as shown at C and D in Fig. 32.

[Illustration: FIG. 32D. ANOTHER TRIAL POSITION OF THE MANIKIN]


~Making Cardboard Models.--~In drawing out your invention you will
often find that you can’t get the image you have in your mind’s eye
down on paper.

There may be the movement of a lever, the turning of a wheel or the
motion of a cam that you cannot quite see through and try as you will
to work it out on paper the thing refuses to materialize. Under such
conditions it would be a great waste of time and money to set about
building a real model but there is an easy way out of the difficulty
and that is to make a cardboard model of the device.

Just as an illustration take the case of an aeroplane. Say that your
big idea is a scheme for controlling the _elevating planes_ and the
_direction rudder_; you have clearly in mind the use of an elevating
plane on each side of the rudder and yet when you try to draw it out
these two parts won’t fit together at all as you expected them to do.

When you reach this point get a sheet of heavy cardboard, shears,
bottle of liquid glue, pins, matches or toothpicks, some thin wire, a
few corks and a sharp knife.

Out of these materials you can build up the _fuselage_, as the body of
the aeroplane is called; next you can fasten on the rudder and then the
elevation planes; and when you have the tail-planes put together with
real materials and actual shapes and sizes they will stand out in bold
relief and you will have no trouble in making your drawings from the
cardboard model.

Or suppose you have an idea for a gyro-motor such as are used for
driving aeroplanes. Now in this motor the shaft to which the pistons
are fastened stands still and the cylinders in which the pistons move
revolve. It is rather a curious motion and not easy for a fellow who is
not posted on mechanics to grasp offhand.

What’s the thing to do? Why, make a cardboard model of the mechanism
using pins for the shafts and you will have a model that will look like
Fig. 33, and when you turn the cardboard disk with the cylinders marked
on it you will see at once exactly how the motor works.

[Illustration: FIG. 33. A CARDBOARD MODEL OF A GYRO ENGINE]

And so it is with many other contrivances; when you come to any part
that doesn’t seem to fit or is not clear, make a cardboard model and
your troubles will vanish as dew-drops in the morning’s sun.




CHAPTER III

THE STATE OF THE ART


Taking it for granted, now, that you have drawn out your invention on
paper and have made cardboard models of the more difficult parts so
that you can see about what your device or machine will look like and
how it will work your next move is to look up the _state of the art_.


~What is Meant by State of the Art.--~The state of the art means
everything that has been published either in books, papers, or in
patents about anything that has been discovered or invented, which has
a bearing on your invention.

As an instance the _state of the art_ of the _dynamo electric machine_,
or _dynamo_ as it is called for short, goes clear back to 1833 when
Faraday made the experiment of passing a wire across the pole of a
magnet and found that a current of electricity was set up in it--that
is in the wire. Since that time hundreds of patents have been taken out
and thousands of articles have been written about dynamos.

All of this information, or _data_ as it is called, goes to make up the
state of the art in the class of dynamos and all of the patents can
be had and many of the articles too if you know how to go about it to
find them and one of the purposes of this chapter is to tell you how
to do it.


~Use of the State of the Art.--~You can easily understand that with all
the thought that has been given to, and the experimental work that has
been put on, dynamos to the end of bettering them it is a pretty hard
thing to make an improvement that has not been made before, though it
is still quite possible to do so.

Suppose, then, you had thought of and worked out on paper some
improvement on the dynamo which you believed to be new and original and
of great value. Certainly since you know that inventors like Edison,
Brush, Weston, Thompson, Tesla, and a hundred other men almost as big,
had applied themselves with diligence to dynamo problems during the
last 40 years you would not care to go very far in spending your time
or your money working on it until you learned whether or not some one
before you had thought of and used the same _principle_.

Yet hundreds of beginners in the field of inventing work along in the
dark because they do not know the state of the art, and always to their
sorrow. So don’t be one of them.


~How to Learn the State of the Art.--~For the reasons I have given
above you will see that it is bad practice to go beyond the point of
working out your invention on paper before you know whether it is
really new or not for though it may be entirely original with you, if
it has been thought of and read before some learned body of scientists,
or printed in some musty trade paper prior to the time you conceived
the idea you haven’t the slightest claim to it, nor is it of the least
value to you.

And so after you have thought out your invention and have made drawings
of it the next step _is not_ to apply for a patent as most patent
attorneys will advise to do, or to have a model made as many model
makers will tell you to do but _to look up the state of the art_ and
see where you are _at_.


~Having a Patent Attorney Look it Up.--~The easiest and quickest way to
learn roughly the state of the art is to have a _preliminary search_,
as it is called, made by a _patent attorney_, which means that he will
look through the files of patents that have been granted by the _United
States Patent Office_ to other inventors for devices or machines of the
kind you are working on.

To do this you must, of course, _retain_ a patent attorney, that is
employ him, and turn the drawings and written description of your
invention over to him. Every patent attorney outside of Washington,
where the patent office is located, has a _correspondent_ or an
associate, that is another patent attorney, who lives there and who
acts for him when necessary.

This latter patent attorney will take your drawings and description
to the library of the patent office, look over the files of patents
there and pick out those which seem to him are most nearly like your
invention.

He will get copies of these patents, send them to your patent attorney
who will in turn hand them to you with your original drawings and you
can then go over them and compare them and judge for yourself whether
you have a really new invention or if it burned in the brain of some
other inventor before you ever dreamed of it.

From the above you might infer that it would be a good scheme to
employ a patent attorney who lives in Washington; but on the contrary
it is better to have a patent attorney in your own city transact this
business for you, if one is to be had, for then you can talk with him
and you will learn many things you couldn’t begin to find out through
correspondence.

Many advertising patent attorneys agree to make what they are pleased
to call a _free search_ for you--and do it while you wait, so to speak.
A free search, or _desk search_, as it is dubbed by those who don’t
make them, is of no value whatever for it is the snap-shot opinion, or
rather a notion, of a patent attorney who is drumming up business by
un-business like methods.

To show how absurd an opinion of this kind is just consider that there
are 43 _divisions_ of inventions in the patent office; each division,
is split up into anywhere from a dozen to nearly 200 _classes_ and that
in some of these classes as many as 12,000 patents have been granted as
in the case of the sewing machine.

And when you ask a patent attorney of this ilk to make a free search
for you he will write back a letter in this tone of voice: I have very
carefully considered your _sketch_, etc., etc. The first payment of
fees necessary to start your case is $20 and upon receipt of this
amount I will be very glad to carry the case forward, etc., etc.

All patent attorneys who advertise that they will make a search for you
free of charge will also make what they call a _special search_ for
which they charge $5.00, and any other patent attorney will make one
for the same price and which is, after all is said and done, only a
_preliminary search_.

You can buy a copy of any patent that has been _issued_ by sending
5 cents in coin--the government won’t take its own stamps--to the
_Commissioner of Patents, Washington, D. C._, that is if you know the
number and date of it and the name of the inventor to whom it was
granted. The patent attorney who makes the preliminary search will send
you several copies of the patents nearest like your drawing without
extra charge as these are, or should be, included in your $5.00 fee.

When you get the copies of these patents go over each one carefully and
see how nearly the pictures are like yours; then read the description
of the invention, or _specification_ as it is called, and compare it
with your own statement, and, finally study the _claims_ at the end of
the specification and pick them to pieces for in these are to be found
what has really been allowed to the inventor by the patent office.

The patents found by the patent attorney in making a preliminary
search of the files and which are sent to you does not by any means
represent the whole state of the art, but they serve a useful purpose
as a starter. The reason it is not complete is because the patents are
usually selected by patent attorneys in virtue of their similarity to
the drawings you have submitted to him. Sometimes, to be sure, he reads
what the specification says and if he is a real good patent attorney he
will sift out a few of the claims, though this is usually due to his
patent training rather than to any conscientious desire on his part to
get at all the facts in the case.

But when you have applied for a patent on your alleged new and useful
improvement and it is being scrutinized by the _examiner_ in the
patent office, he will look up the state of the art in all its devious
_ramifications_ for this is what he is paid to do by the people of the
United States, though he thinks it is the officials in Washington who
employ him. At any rate he has plenty of time to do it in and ample
assistance to do it with.

Nor does he merely take a glance at the drawings, specifications and
claims of your patent application and compare them casually with others
that have been granted along the same line of endeavor, but, instead,
when enough pressure is brought to bear, he will look up everything
that has ever been published in all languages, including the barbaric
_ro_,[1] since Adam was a boy.

At other times and for no reason at all, or so it seems, he will of a
verity go to sleep on the job in his sub-cellar and let an application
slip through his room in a few months, while he will spend years
on another application of the same kind. Of course if you are the
fortunate one you will be glad to get a patent granted so easily; your
patent attorney is glad because he has your money in his pocket and the
examiner is glad because he has made a friend of his glad.

To have everybody glad is a nice thing, you will allow, but don’t
crow too soon for there is a hole in the average patent big enough to
drive a horse and wagon through. If your patent is for an invention of
genuine merit you will not be alone very long in the field and should
you commence to make anything that looks like real money out of it you
will find some other genius with an invention and a patent, as like
yours as the other Siamese twin and if you don’t sue him he will sue
you and then you can fight it out in the courts.

Even as right is always on the side of the army with the heaviest
artillery, if there are enough shells, so, too, justice is always on
the side of the inventor who has the smoothest patent attorney and the
cleverest experts if they have enough ammunition in the way of some
claims. While it requires skill to draw up good claims they can in any
case be made better where the state of the art is known by yourself and
your patent attorney.


~How to Look It Up Yourself.--~Whatever the nature of the invention
you are working on you should read up its history from its earliest
beginnings and in this age of papers, books and public libraries this
is an easy, entertaining and profitable thing to do.

As an illustration take the art of flying and let’s suppose you are
working on a new _wing_, or _main-plane_, for an aëroplane; if you
will go over the list of books sold by book publishers, or consult
the catalogue of a public library you will find books on flying, or
_aviation_ as it is called, that will give you a full account of the
development of flying machines; and if you will get the right book
it will picture and describe all the forms of wings that have been
invented and patented up to the time the book went to press. Then there
are weekly and monthly papers published which are devoted entirely to
the theory and practice of flying and by reading these you will be able
to keep right up to the _entering edge_ of the art.

Now what I have said about flying is just as true of whatever else
you may happen to be working on, for books and papers are printed and
published about nearly every subject you can think of, from aviation to
wireless telegraphy; by reading up on the subject of and allied to your
invention you will soon have the history of it by heart and this makes
up a large part of the state of the art.

Another and fortunate thing when you look up the state of the art a lot
of other ideas will surge helter-skelter through your mind and if you
are careful to write them down many of them will be of much value to
you in the furtherance of your invention.

If you live in a large city it is an easy matter to look up the
patents that have been granted for inventions in your class, for you
will find an _Index of the Patent Office_ in the public library which
gives the number and date of the patent you want and the _patentee’s
name_. The _Index_ is published every year by the Unites States patent
office and it gives the alphabetical list of the patentees and of the
inventors to whom patents were granted for that year.

[Illustration: FIG. 34. THE OFFICIAL GAZETTE

FIG. 35. PATENT SPECIFICATIONS

FIG. 36. INDEX TO PATENTS]

Having found the patent you want to look into, get the _Official
Gazette_ of the patent office for the same year and by looking up the
number, or patentee, or invention, or all of them, you can easily
locate an _excerpt_ of the patent and then you can take a look at the
drawing and read the principal claims.

The _Official Gazette_ is published every week by the patent office and
it contains a picture and a brief description of each patent issued for
that week, together with the number and date of the patent, the name
of the patentee and of the invention.

Should you require more information about a patent than is given in the
_Gazette_ you can look up a copy of the patent, or _full specification_
as it is called, and these are bound in handsome volumes of 100 patents
each, or at least, this is the practice of the New York Public Library.

In every library that has a _patent section_, that is a part devoted
to patents, there is a librarian in charge who will either find any
patent you want or who will show you how to use the _Index_, _Official
Gazette_ and the volumes of the _full specifications_.

The patent attorneys in Washington have things much easier as all of
the patents are bound in books according to the class they are in and
they only need to look over the volumes of a given class to choose
those they want.

When you have learned everything you can from books, papers and copies
of patents already granted about the subject you are interested in you
will have a pretty clear idea of the state of the art and whether you
are working in a virgin field or one that has been sown with the same
kind of inventions by others.

But there is another and most important part of the state of the
art which neither you nor your patent attorneys can find out about
until after you have filed your application for a patent; this is
the information contained in the applications for patents by other
inventors before your application was filed.

Should another application _disclose_ either in whole or in part an
invention like, or nearly like, yours, or rather that your invention
is like, or nearly like, some one’s else, the patent examiner declares
what is called an _interference_, of which more will be said in another
chapter, and this gives the patent attorneys on both sides another
chance to rake in a few more fees.


~What to Do When You Find There Are No Other Improvements Like
Yours.--~After you have looked up, or have had looked up, the state
of the art as carefully as possible, and you are satisfied that your
invention, or improvement, is different from everything else you have
been able to find, you should by all means go ahead and make such
experiments, or build a working model, as the case may be, in order
that you may know that all you have thought about it is really true.

As soon as your experiments are completed or your model is finished so
that you know exactly what you want to _claim_ as being strictly new
and novel and original with you, then you are in shape to hire a patent
attorney to draw up your patent application and file it and don’t do
the latter a moment before.

A patent application based largely on what you _guess_, is a patent
when granted without value for it can no more cover the exact facts in
the case when these are finally worked out than a description one might
write about an imaginary trip to Europe would be likely to fit the true
details of a real trip which he would make sometime thereafter.


~When You Find There is a Resemblance.--~Very often you will find
after you have looked up the state of the art that some other inventor
has patented a device that seems on the face of it quite like yours and
yet when you examine them critically, compare them closely and bring
thought to bear upon them you will be able to distinguish a difference
and often in several respects.

Sometimes this difference, though it seems to be small, is a mighty one
when it comes to producing results as for instance when Elias Howe used
a needle with the eye near its point instead of in its head and so made
the sewing machine a commercial success. And yet a patent examiner of
to-day would not be likely to see any difference in a needle with an
eye in its head and one with an eye near its point, that is, if he had
never seen either one before.

If you have made a machine to do a certain thing and you find that
another machine has been invented that does the same thing and in
the same way you may be able to change the mechanical movements, or
electrical devices, until you are able to get the same or a better
result by other and better means. It is all very easy to tell you to do
this but in practice it is often a mighty hard thing to accomplish.

The Bell telephone is an example of such difficulties, for while both
transmitters and receivers can be made which work on principles quite
different from those now in use the results are not nearly as good and
hence the inventions have no practical value.


~When Others Are Exactly Like Yours.--~But when you find that your
great idea has been thought of and worked out and patented by some
other inventor ahead of you and that both the cause and effect which
you and he arrived at are the same, then the best thing to do is to
drop it like a hot potato and invent something else.

 NOTE.--The Patent Office publishes a _Manual of Classification_, price
 $1, which lists all of the sub-divisions of each class. Take as an
 illustration _Explosives_, which is _Class 53_. This is subdivided
 into six such classes, namely: (1) Blasting Powder; (2) Fulminates;
 (3) Nitro Compounds; (4) Gun Powder; (5) Matches; (6) Pyrotechnic
 Compounds.




CHAPTER IV

HOW TO EXPERIMENT


The kind of experimenting you will do will, of course, depend
altogether on the nature of the invention on which you are working.

But, as good fortune would have it if you are not mechanically inclined
you are not apt to hit upon a mechanical invention. And if you know
nothing of electricity, you are not likely to think out an improved
electrical device.

But this much is certain if you are going to experiment the right way
you must know something about the right way to experiment. No one
should expect to work out to a successful conclusion a new machine or
apply a new improvement to an old machine if he knows nothing of the
_first principles of mechanics_ or _about mechanical movements_, and by
rights he ought to have some knowledge of _machine design_.

And the above statement is just as true of electrical inventions. A
worker who does not know the difference between a binding post and
an alternating current need not expect to progress very far with an
invention of, say, an electric block signal system--unless he calls in
an expert to help him; but what he should do is to study the principles
of electricity and magnetism, learn the various currents that can be
used and what apparatus and instruments are needed for utilizing these
currents.

The same thing applies to inventions in chemistry in that to work
intelligently you must know about the properties of substances,
chemical change and acids, bases and salts. And with electro-chemistry
both a knowledge of chemistry and electricity are needed.

It is easy to see that it would not be possible in the limited space
I have here to say more than a word or two about the subjects of
mechanics, electricity, chemistry and electro-chemistry when each
requires a whole chapter to explain it even in a rough way and a whole
book to explain it thoroughly. But there are a few things I can tell
you about them that will put you on the right track and then I shall
give you the names of some books that will be of great service to you
when you are in need of them, and with your help we’ll make a real
inventor of you.


~How to Experiment with Machines.--~Any one who possesses the
slightest bent for mechanics can work out improvements on devices like
egg-beaters and monkey-wrenches and feel their way as they go along.

But when it comes to designing and building real machines where
numerous levers, gears, and springs are combined to make a working
unit you should by all means read up on the subjects of _work, energy
and power_, learn about the _six mechanical powers_--and the action of
machines in general. The following definitions will give you an idea
about all of them.


~Work, Energy and Power.--~A wheel will not turn of its own accord but
if it is moved round by some _force_ applied to it such as the hand, a
coiled spring or a motor, _work_ is done. In fact whenever a thing is
made to change its position work is done.

The power to do work is caused by _energy_; energy is developed when
some force is applied and can be stored up in bodies as when a ball
is thrown. When the energy stops acting, or is used up, there can no
longer be any work done. Energy can be _transferred_ from one body
to another, as from a clock-spring to a wheel, or from one wheel to
another wheel; and energy can be _transformed_, as the chemical energy
of a battery into the rotary energy of a motor or from steam into
mechanical motion.

The _unit of work_ is the _foot-pound_ and this is the work done to
raise _one pound one foot high_. The _rate_ of doing work is the _horse
power_ and a horse power is equal to lifting 550 foot-pounds in a
second, or 33,000 foot-pounds in a minute.

Energy may be either _potential_ or _kinetic_; _potential energy_ means
energy that is stored up and with nothing to act on, and for this
reason it is called _energy of position_. The electric charge of a
Leyden jar is potential energy but the moment it is released it makes
a spark and becomes _kinetic energy_ or _energy of motion_. Potential
energy can be changed into kinetic energy and kinetic energy back again
into potential energy with amazing freedom. Energy has a definite
relation to _velocity_ which means that when the speed of a moving
body is increased its power to do work is also increased.

Like matter, energy cannot be destroyed, and so all of it taken
together is called a _constant quantity_. When the energy stored up
in a spring, or a battery, has been used the energy is not destroyed,
though it may be very hard to find out where it has gone, but you may
know that it has vanished in heat and in other forms of energy.


~Work Against Friction.--~The chief resistance which machines have
to overcome is caused by _friction_. Since there is no such thing as
a perfectly smooth surface friction is always present in machines
and much energy must be spent in overcoming it. The energy wasted by
friction is not destroyed but is transformed into another kind of
energy and that is heat. When a marble is rolled over the surface of
a table there is less friction between the two than when the marble
slides across the table. Hence with _ball bearings_ there is less
friction than with _cone bearings_. (See Appendix I.)


~Forms of Energy.--~There are nine forms of energy that you can make
use of in your experiments and in your inventions, and these are:

                      {  Bodies in Motion--kinetic.
                      {  Bodies under Stress        {
  ENERGY OF MASSES    {   (like a coiled spring).   {  Potential.
                      {  Bodies attracted by        {
                      {   Gravitation.              {
                      {  Sound--both kinetic and potential.

                      {  Heat.
  ENERGY OF MOLECULES {  Molecular and Atomic Energy.
   AND ATOMS          {  Chemical Action.

  ENERGY OF ETHER     {  Electric and Magnetic Actions.
                      {  Light and Invisible Radiation.


~Machines and the Principles of Machinery.--~A _machine_ is a
contrivance of mechanical parts by which energy is transferred from
one part to another. Beside the amount of energy required for doing
useful work there must be an extra amount for overcoming the friction.
Remember that no machine can either create energy or increase it,
and, as you have seen, every machine wastes some energy in friction;
this being true it must be clear then that it is impossible to make a
machine which when once set in motion would continue to run forever, or
at least until its parts were worn out. So don’t waste _your energy_ in
trying to invent a _perpetual motion_ machine.


~The Uses of Machines.--~These are many and varied from a commercial
point of view in that they are designed to do better, faster or cheaper
work and sometimes all of these good qualities are found in a single
machine.

From a mechanical point of view, though, a machine is used to

(1) Change one form of energy into another form, as steam into
electricity.

(2) To make a slow moving, but powerful force produce a high speed or
velocity, as in a sewing machine.

(3) To change a small, fast moving force into a powerful force, as in
the action of a crowbar.

(4) To change the direction of a force so that the power can be
applied where and when it is needed, and

(5) To make use of whatever force is at hand as the strength of
animals, wind, water, steam, gas and electricity.


~The Six Mechanical Powers.--~As a matter of fact there are really only
two of these, namely the _lever_ and the _inclined plane_, the other
four, that is the _wheel_ and _axle_, the _pulley_, the _wedge_ and the
_screw_ being simply modified forms of the first two.

[Illustration: FIG. 37A. A LEVER OF THE FIRST CLASS]

[Illustration: FIG. 37B. A PAIR OF PLIERS]

The _lever_ is a rigid bar resting on, and which can be moved about a
fixed point, called the _fulcrum_. There are three classes of levers
and these are:

[Illustration: FIG. 38A. A LEVER OF THE SECOND CLASS]

[Illustration: FIG. 38B. A PAIR OF WIRE SPLICING CLAMPS]

(1) Where the fulcrum is placed between the load and the power which
moves it, as shown at A, Fig. 37; a pair of shears, pliers, a balance
and a crowbar are levers of the first-class, see B, Fig, 37.

[Illustration: FIG. 39A. A LEVER OF THE THIRD CLASS]

[Illustration: FIG. 39B. A PAIR OF SUGAR TONGS]

(2) Where the load is applied between the power and the fulcrum, as
shown at A, Fig. 38; a lemon squeezer and wire splicing clamps are
examples of this class; see B, Fig. 38, and

[Illustration: FIG. 40. A BENT LEVER]

(3) Where the power is applied between the load and the fulcrum as
shown at A, Fig. 39; the foot treadle of a jig saw and sugar tongs are
levers of this class. See B, Fig. 39. Then there is the _bent lever_,
as shown in Fig. 40, where the power and load do not act parallel
with each other, and the _compound lever_ which takes the place of
a single long lever as shown in Fig. 41, and which is used in large
platform-scales.

[Illustration: FIG. 41. A COMPOUND LEVER]

The _wheel_ and _axle_ is really a form of lever and fulcrum. The axle
provides a continuous fulcrum as shown in Fig. 42. Trains of wheel
work, such as are used in clocks and other mechanical devices, are
used to change a slow moving powerful force into a high speed, or
velocity, or the other way about. Fig. 43 shows a train of wheel work.

[Illustration: FIG. 42. THE WHEEL AND AXLE IS A MODIFIED LEVER

The power is applied at A, the weight is at B, and the Fulcrum is at C.]

[Illustration: FIG. 43. A TRAIN OF WHEELS OR WHEEL WORK]

The _pulley_ is a wheel with a cord, rope or belt running round it as
shown in Fig. 44. It is used to transmit power and also to change the
direction of it. A pulley can be either fixed or movable. A _compound
pulley_ makes it possible to raise a heavy weight with a very small
force, not by increasing the energy, but by transposing _velocity_ into
_power_.

[Illustration: FIG. 44. A FIXED PULLEY]

[Illustration: FIG. 45A. AN INCLINED PLANE]

[Illustration: FIG. 45B. ONE OF THE USES OF AN INCLINED PLANE]

The _inclined plane_ is any hard smooth surface set at a slant to the
force to be overcome. A barrel can be rolled up an inclined plane
against the force of gravity, as shown in Fig. 45, while it could not
be lifted straight up to the same height.

The _wedge_ is simply an inclined plane on a small scale. It is useful
where a great force must be exerted through a small distance, as in
splitting a stick of wood, as shown in Fig. 46.

[Illustration: FIG. 46A. A SIMPLE WEDGE]

[Illustration: FIG. 46B. TWO WEDGES FORM A PRINTER’S QUOIN]

A _screw_ is also a modified form of an inclined plane. By means of a
screw great pressures can be exerted in a small space and here again
a powerful force is had with a corresponding loss of velocity. It is
shown in Fig. 47.

[Illustration: FIG. 47A. THE THEORY OF A SCREW]

[Illustration: FIG. 47B. A SCREW CLAMP]


~Compound Machines.--~Any of the above six simple machines can be
combined with any or all of the others and every machine that has ever
been invented for any purpose is made up of a combination of these six
mechanical powers.

Since the beginning of invention there has been made by combining these
six mechanical powers in different ways, a large number of simple
machines called _mechanical movements_; and there has not been a single
new mechanical movement invented in many years.

Hence when you begin to work on your machine don’t waste time and
energy trying to devise the mechanical movement you need, or what is
still more foolish attempting to invent a new mechanical movement but
look at the pictures in Fig. 48 which gives over 60 of the most useful
mechanical movements. If you cannot find one among them that will do
the work then look for it in Gardner D. Hiscock’s book of _Mechanical
Movements_ which gives them all.


~Books.--~And it would be a good idea for you to read one of the
following books which you can, most likely, get at any library:

  _Elementary Physics_: Elroy M. Avery.
  _Elements of Physics_: Edwin J. Houston.
  _Elements of Physics_: George H. Hoadley.
  _College Physics_: A. L. Kimball.

The first-named books go deeply enough into the subject of physics for
all ordinary purposes while the last named is very thorough and has
a lot of _math_ in it; and all of them treat of liquids, air,
electricity and magnetism, sound, heat and light. In whatever field you
are working a general knowledge of physics will give you the key to a
new and a mighty interesting world.

[Illustration: FIG. 48A. SOME USEFUL MECHANICAL MOVEMENTS]

[Illustration: FIG. 48B. USEFUL MECHANICAL MOVEMENTS]

[Illustration: FIG. 48C. USEFUL MECHANICAL MOVEMENTS]

[Illustration: FIG. 48D. USEFUL MECHANICAL MOVEMENTS]

With the first principles of mechanics well in mind and the mechanical
movements I have given, you can go on with your experiments in a safe
and sensible way.


~How to Experiment with Electricity.--~_Electricity_ is very much like
mechanics in that any one can put up an electric bell or screw in a
plug-fuse but to experiment and build an apparatus in which electricity
and magnetism are the powers used you must know how electricity
is generated, how magnetism is produced, the different forms of
electricity that are available and finally the kinds of apparatus best
suited for the work that is required of them.


~Forms of Electricity.--~Though there is only one kind of electricity
it can be divided into four classes, or forms, and these are:

(1) Electricity at rest, or _static electricity_, that is electricity
stored up but not active as in a charged Leyden jar.

(2) Electricity in locomotion, or _current electricity_, in which
electricity flows along wires, through solutions and other conductors
when it is able to do work.

(3) Electricity in rotation, or _magnetism_ in which electric whirls
produce attraction and repulsion, and:

(4) Electricity in vibration, or _radiation_ in which electric
charges moving to and fro millions of times a second set up waves in
the _ether_ which our eyes can see and which we call _light_. Then
there are waves much too short for the eye to see and these are called
_ultra-violet_ waves; there are waves too long for the eye to see and
these are the _infra-red_ waves which we can feel for they are _heat_
waves, and finally there are very long waves set up in the ether
by surging _high frequency_ currents in wires and these are called
_electric_ or wireless waves.[2]


~Static Electricity.--~You can think of electricity as being a fluid,
like water, for it has both _quantity_ and _pressure_, and in many ways
it acts like a fluid.

If you filled a tank, raised above the ground, with water, the latter
would be at rest, but it would be under pressure too and the moment a
hole was bored in any part of the tank below the level of the water it
would squirt out; in other words the _potential water_ would be changed
into _kinetic_ water or water in locomotion. If, now, you charge a
_Leyden jar_, or a _condenser_, with electricity it will be at rest
until you bring the alternate coatings of tin-foil closely together
when a spark will result and a current will flow.

Static electricity is generated by _friction_ and by _induction_, but
the electricity so produced is very small in quantity and very high in
pressure. A Leyden jar, or other condenser can be charged, though, with
a low pressure current of electricity, as in a _spark coil_.


~Current Electricity.--~Whenever electricity flows in a wire, or other
conductor, it acts like water flowing through a pipe and it is then
called _current electricity_. The two most common ways to generate a
current of electricity is by means of a _chemical battery_ and by a
_dynamo electric machine_.

A current of electricity may have a small _current strength_, as its
quantity is called, and a high _voltage_, as its pressure is called,
like the discharge of a Leyden jar, or it may have a large current
strength and a low voltage, as a current generated by a battery.

A _direct current_, see Fig. 49, is a current which flows steadily
in one direction and this can be generated by a battery or a dynamo.
An _interrupted current_, see Fig. 50, is a current that is _made_
and _broken_ a number of times a minute and this is usually done by
a _vibrator_, or _interruptor_ as it is often called. A _pulsating
current_, see Fig. 51, is one whose current strength is varied. One
way to produce a pulsating current is to talk into a _telephone
transmitter_ which is connected with a battery.

[Illustration: FIG. 49. A STEADY DIRECT CURRENT]

[Illustration: FIG. 50. AN INTERRUPTED DIRECT CURRENT]

[Illustration: FIG. 51. A PULSATING DIRECT CURRENT]

An _alternating current_, see Fig. 52, is one which flows first in one
direction and then in the other direction. A _magneto-electric machine_
and an _alternating current generator_ are the means for generating
this form of current. Alternating current can be produced from a direct
current by using an _induction coil_, or _spark coil_ as it is called.
But a steady direct current can be obtained from an alternating current
only by coupling an _alternating current motor_ to a _direct current_
dynamo.

[Illustration: FIG. 52. AN ALTERNATING CURRENT]

The pressure, or voltage, of an alternating current can be _stepped
up_ or _stepped down_, that is, raised or lowered, by means of a
_transformer_, which is the simplest form of induction coil. The
current strength varies proportionately with the charges in pressure
so that there can never be any increase in the total amount of energy
but there is always a loss of energy due to heating and other causes.
The moral again is that an electrically driven perpetual motion
machine is a delusion and a snare. Alternating current can be changed
into _interrupted direct current_, see Fig. 53, by an _electrolytic
rectifier_ or a _mercury vapor tube_.

[Illustration: FIG. 53. ALTERNATING CURRENT CHANGED INTO AN INTERRUPTED
DIRECT CURRENT]

A _high tension current_ is an alternating current of sufficient
pressure to make a _jump-spark_; it can be produced by a _high-tension
magneto_, or a _spark coil_. An alternating current is generally
considered one that changes its direction less than 100,000 times a
second; when it changes its direction 100,000 times or more a second it
is called an _oscillating current_, see Fig. 54, or a _high frequency
current_, and this is the form of current that is used for sending out
_wireless waves_.

[Illustration: FIG. 54. A PERIODIC OSCILLATING CURRENT]

The only known way to set up oscillating currents of really high
frequency is by discharging the stored up electricity of a condenser,
or its equivalent, through a circuit of small resistance by means of a
spark, or an arc. The latter sets up sustained oscillations as shown in
Fig. 55. _High frequency alternators_ (machines) have been built which
generate alternating currents of over 100,000 _cycles_ per second.

[Illustration: FIG. 55. A SUSTAINED OSCILLATING CURRENT]


~Magnetism.--~A bar of steel can be made magnetic by rubbing it on a
_permanent steel magnet_ or on an _electromagnet_, or winding a number
of turns of wire around it and passing a current through the wire.

If a bar of soft iron is placed in a coil of wire and a current is made
to flow round it the iron will become a magnet but remains so only
while the current is flowing, and this forms an _electromagnet_. An
electromagnet works best on a direct current but an alternating current
can also be used to energize it.

A coil of wire with an _air core_, that is without either an iron or
a steel core, becomes a magnet when a current is made to flow through
it. If, now, one end of a bar of soft iron is slipped into the hole in
the coil of wire and the current is turned on the iron bar, or core,
will be drawn into it. This kind of a magnet is called a _plunger
electromagnet_, or _solenoid_.


~Radiation.--~Whenever you light a match, or make a light by any other
means, electric charges on the molecules of the substance which is
heated vibrate violently to and fro and the minute surgings of the
electric charges set up _electro-magnetic_ waves in the _ether_ which
the eye can see and the brain can sense and this is what we call
_light_.

When some substances are intensely heated, as for instance, the
_carbons_ of an _arc lamp_, waves are also sent out which are too short
for the eye to see but which will nevertheless affect a photographic
plate. These are called _ultra-violet waves_. The _infra-red_ waves are
too long for the eye to see but the nerves of our bodies sense them as
heat.

[Illustration: FIG. 56A. SOME USEFUL ELECTRO-MECHANICAL DEVICES]

[Illustration: FIG. 56B. SOME USEFUL ELECTRO-MECHANICAL DEVICES]

In conclusion take this bit of advice: don’t try to invent
a new kind of electric current and don’t try to devise a new
_electro-mechanical movement_ for in either case you will waste your
time. Every form of current and every kind of electro-mechanical device
you will need for any machine which you may invent are at hand and
ready for use. Fig. 56 shows a number of electro-mechanical devices and
these will aid you in getting the result you want.


~Books.--~The books on physics listed on page 69 go deeply enough into
the subject of static and current electricity and magnetism for all
ordinary purposes of invention, but if you are interested in _wireless_
and _high frequency electricity_ then I would suggest that you read the
following books:

  _The Book of Wireless._ A. F. Collins.
  _Manual of Wireless Telegraphy._ A. F. Collins.
  _Wireless Telegraphy and High Frequency Electricity._ H. LaV. Twining.
  _Electric Wave Telegraphy._ J. A. Fleming.

[Illustration: FIG. 57. AN AMMETER FOR MEASURING CURRENT]

[Illustration: FIG. 58. A VOLTMETER FOR MEASURING PRESSURE]


~Your Electrical Equipment.--~Should your invention call for
experiments in electricity, especially where the amount of current used
is a factor, you should provide yourself with a good _ammeter_, as
shown in Fig. 57, for measuring the current in _amperes_, and a _volt
meter_, as shown in Fig. 58, for measuring the pressure, or _voltage_,
in _volts_. (See Appendix O.)

Where the resistance in _ohms_ of a wire, or a circuit of any kind must
be known a _combined bridge and resistance box_ is the best way to
make accurate measurements. Resistance boxes measuring from .001 ohm
to 17.600 ohms can be bought of the L. E. Knott Apparatus Co., Boston,
Mass., for about $18.00. It is shown in Fig. 59.

[Illustration: FIG. 59. A RESISTANCE BOX FOR MEASURING THE RESISTANCE
OF WIRES]

A large number of electrical devices call for winding wire on cores,
spools, coils, etc. Nearly all windings can be done on a lathe but if a
lathe is not among your treasured possessions you can make a _winder_
which will serve all ordinary purposes. The drawings shown at A and B,
Fig. 60, give all the details of construction and you can make one
chiefly of wood of whatever size your winding calls for.

[Illustration: FIG. 60. AN EASILY MADE WINDING DEVICE

A. A side view

B. An end view]


~How to Experiment with Chemistry.--~It is a pleasant pastime to make
chemical experiments after a known formula but it is quite a different
and a difficult thing to try to invent some new chemical compound when
you know little or nothing of chemistry.

If your invention calls for some _chemical combination_ or
_decomposition_ or _double decomposition_--these are the three kinds
of chemical action--get an elementary book on chemistry and study it
until you really know it and then you will have a bed-rock foundation
on which to build up your invention.

You may say it is all very well to read a book on chemistry and learn
all about it but it’s a mighty hard thing to do without a teacher. My
answer is if you are not interested in chemistry, you will certainly
find the study of it up-hill work and very tedious.

But if you are working on an invention like, say, _synthetic
gems_, that is making real rubies and sapphires and emeralds in an
oxy-hydrogen furnace, see Fig. 61, you will not only study but you
will study harder than you have ever studied before if you believe it
will help you to find the solution of the gem problem. It is under
these conditions that work-study becomes play-study and you will
be fascinated with it and it will then prove pleasant as well as
profitable.

[Illustration: FIG. 61A. MAKING A REAL RUBY BY CHEMISTRY]

[Illustration: FIG. 61B. RUBY BOULES AS THEY COME FROM THE FURNACE]

[Illustration: FIG. 61C. SYNTHETIC RUBIES AFTER THEY ARE CUT]


~Your Chemical Equipment.--~The chemical apparatus you will require
depends entirely on the class of work you are doing but for all
ordinary chemical experiments the following apparatus will be found
useful: (1) a nest of beakers; (2) a jeweler’s blowpipe; (3) one-half
dozen wide mouth flint bottles; (4) a Bunsen burner with regulator,
that is if you have gas, or (5) an alcohol lamp; (6) a glass U tube;
(7) a nest of Hessian crucibles; (8) a nest of porcelain crucibles; (9)
an evaporating dish; (10) a lead dish; (11) a couple of glass funnels;
(12) a glass bottle with a two hole stopper; (13) half a pound of glass
tubing; (14) a porcelain mortar and pestle; (15) a plain glass retort;
(16) a stoppered retort; (17) 3 or 4 feet of ¼ inch rubber tubing; (18)
a sand bath; (19) a dozen test tubes; (20) a test-tube stand; (21) a
test-tube clamp; (22) a test-tube brush; (23) an iron retort tripod;
(24) one-half dozen watch glasses; (25) a water bath; (26) some wire
clamp supports; (27) a couple of platinum plates; (28) an air bath;
(29) a burette; (30) a pinch-cock, and (31) a brass scale with weights.
See Fig. 62.

All of the above apparatus can be bought of any dealer in chemical or
school apparatus for ten or twelve dollars. For advanced work you will
need other apparatus but whatever your requirements may be you can
either buy the apparatus ready made or have it made to order.

As to chemicals these will likewise depend on the nature of your
experiments. Send to Eimer and Amend, 205 Third avenue, New York
City, for a catalogue and price list of chemicals and chemical
apparatus as they sell everything used by chemists and electrochemists.

[Illustration: FIG. 62. SOME USEFUL CHEMICAL APPARATUS]


~Books.--~The following books with the exception of the last one are
good elementary treatises on chemistry:

  1.--_Elementary Chemistry._ Smith.
  2.--_First Principles of Chemistry._ Brownlee.
  3.--_Chemistry._ Remsen.
  4.--_Complete Chemistry._ Avery.


~How to Experiment with Electro-Chemistry.--~In working out
electro-chemical inventions you require a knowledge of both electricity
and chemistry for it is the electric current that produces the chemical
change either directly or indirectly.

[Illustration: FIG. 63A. AN ELECTRIC FURNACE, SHOWING THE DIFFERENT
PARTS]

An electric battery of any kind is electro-chemical in action and so
is _electroplating_ and _electrotyping_ but these are old inventions.
The production of _ozone_ and _nitric acid_ from the air by the action
of an electric spark; of coal tar colors by _electrolysis_; the
_electrolytic_ refining of copper and the electrolytic production of
aluminum are electro-chemical inventions in which the action of the
electric current is direct. And they are inventions of great importance
and of recent date.

[Illustration: FIG. 63B. AN ELECTRIC FURNACE IN OPERATION]

Then there are a large number of indirect electro-chemical processes in
which the electric current is used to produce heat as in the electric
furnace. Genuine diamonds, though too small and too costly to have any
commercial value, have been made in the electric furnace, shown in
Fig. 63. _Calcium carbide_ for making acetylene gas; _carborundum_,
an abrasive that is better than emery; _electric smelting_ and the
_reduction_ of _iron ore_ with carbon are all new electric furnace
inventions of great value, and there are many others.


BOOK.

 _The Elements of Electro-Chemistry Treated Experimentally._ By Lüpke.




CHAPTER V

MAKING A MODEL


At the end of the chapter on drawing I explained how you could make
models of mechanical movements of cardboard. And you will remember that
the purpose of these simple models is to clear up points that are hazy
when you are working out your invention on paper.


~Kinds of Models.--~Now besides cardboard models there are some other
kinds, the chief ones being (1) _rough models_; (2) _scale models_ and
(3) _working models_, and each of these kinds is useful in its own way.
The kind you should make, or have made, will depend on the bulge of
your pocketbook as well as on the nature of your invention as you will
presently see.

There was a time when the United States patent office required a model
of every invention for which a patent application was made; as a result
the noble patent office finally became a museum filled with antique
models instead of an office in which business was transacted for and
with inventors.

The government officials then concluded that the _patent examiners_
didn’t really need to see the models anyway and then and there they
ordered that a patent application only need be sent to the patent
office--with one exception; this exception is made when a would-be
inventor applies for a patent on a perpetual motion machine and then
he is asked for a _working model_ and if this is not forthcoming--and
of course it never is--no further attention is paid to him or to his
application.

[Illustration: FIG. 64. A ROUGH MODEL OF AN ELECTRIC MOTOR DRIVE FOR A
LOCOMOTIVE]


~Rough Models.--~After you have made the drawings and experiments which
your invention calls for and both have worked out to your satisfaction
you will then have a burning desire to see the result of your efforts
in a more substantial form.

Some machines in which there are only a few moving parts need not be
built up very carefully, or to exact scale or even of the materials the
marketable product is to have in it. Very often a model can be made of
wood and scrap metals that will do and show everything that you want it
to. See Fig. 64.

Should you have to employ a patent attorney who lives at a distance
from you, say one who has an office in Chicago, Philadelphia or Boston,
a rough model of your invention will be of great help to him for it
will give him an insight into its workings and its possibilities that
he is not apt to get from studying your drawings and description unless
you are a good mechanical draftsman and he is above the average in his
profession.

[Illustration: FIG. 65. A SCALE MODEL OF AN AEROPLANE]


~Scale Models.--~Scale models are usually miniatures of the full sized
machine, that is every part of the scale model is reduced in proportion
from the dimensions of the big machine, say 1 inch to the foot or
whatever you want to make it.

Like rough models scale models need not be actual working models,
indeed in many cases it is very hard if not impossible to make a scale
model which will run or work like a full sized machine, unless the
model is made very large, as for instance model aeroplanes fitted with
motors of any other kind than those made of rubber strands. Fig. 65
shows a scale model of an aeroplane.

[Illustration: FIG. 66. A TOY HELIOCOPTER]

Then again sometimes a scale model will work to perfection and when a
full sized machine is built it will not work at all as in the case of
the _heliocopter_, that is, a flying machine having a screw with blades
like a propeller and which when it is rapidly spun by means of a string
like a top will rise in the air to a height and sail away to a distance
of a hundred feet or more. Fig. 66 shows a toy _heliocopter_, or
aerial top as it is called. Many attempts have been made to build full
sized flying machines on the principle of the toy heliocopter but so
far none of them have been able to get off of the ground.

[Illustration: FIG. 67. A WORKING MODEL OF A BRITISH EXPRESS LOCOMOTIVE]

Then again there are many machines that can be made of any size and
which will work equally well. Fig. 67 is a scale model of a British
express locomotive. It is 4 feet long and an exact scale model which
can be fired up with coal and it will make a speed of 10 miles an hour.

A scale model of your invention, if it is a machine, or an electrical
apparatus, when built by an expert model maker, makes a mighty pretty
display and will never fail to attract attention wherever it may be
shown.


~Working Models.--~A working model may be a scale model as you have
seen or it may be a full sized machine or of any size between these
limits.

When you have your invention past the drawing board and up to the shop
bench by all means make a working model of it and if possible make
it full size. This kind of a model is the proof you want that your
invention will work when it is put to the test and by making a working
model you will find lots of changes little and big that are needed and
which when made will improve its operation wonderfully.

And however carefully you have worked out your invention on paper you
will find that when you come to make a model, or have one made, you
will have to change it not once but many times, that is if it is a
machine in which a number of parts are made use of and you may have to
re-design it and re-construct it several times.

For this reason it is a waste of money to build a fine appearing and
costly model in the beginning but what you should do is to make one
that will work without regard to its looks so that you can experiment
with it, overhaul it, tear it down, build it up again and so on until
you are satisfied with it and the results it produces, if such a thing
is possible, before you even begin to talk to a patent attorney about
applying for a patent on it.

Nearly every _tyro_ inventor seems to believe that the only way to keep
honest folks from stealing his invention is to apply for a patent on
it immediately. You will remember I pointed out in the first chapter
how to protect your first idea by signatures and _affidavits_ and
protection of this kind is just as good, and in my opinion just as
safe, and in every way better than to rush off and apply for a patent
and--though of course money is of no object--it is cheaper by at least
$35.00.

Again as I stated in the preceding chapter if you apply for a patent
before you have made a working model of it you will find when you
finally get your model finished it will be so at variance with what
you have written in your specification and claims that you will hardly
be able to recognize it as being the same invention; and besides there
will be the trouble and the expense of changing your drawings and
specification and claims.

On the other hand when you have finished your model to the point where
it will do the work you want it to do you are in a position then to
make a new and accurate set of drawings, to write a clear description
of how the machine works and to draw up your claims with the certainty
of knowing just what you have and what you want to ask for--in a word
you are ready to do business with the patent office.


~Ways to Make a Model.--~The way in which you get your model made
depends on several things and over these you will have little or no
control.

There are two ways for you to get a model made of your invention and
these are (1) to make it yourself and (2) to have a model maker make it
for you.

These two general ways may be further divided into several sub-ways and
among these are (a) for you to have your own workshop, or laboratory
and hire machinists, or electricians, or chemists, and have them do
the work under your direction; (b) for you to give a model maker the
job and have him, or his men, do it under your supervision and (c) for
you to have separate parts of it made by various model makers and then
assemble them in your own shop.

If you are a little skilled in the use of tools there isn’t anything
I know of that will give you greater pleasure than to make each part
of your model with your own hands in your own shop and watch it grow
day by day until it becomes in truth the very apple of your eye. At
least that is the way I feel about it. Moreover it gives you a sense of
security you cannot have when the work is in some one’s else hands.

In making a machine from your own ideas and plans no one can do the
work so well as yourself provided you can do the work at all and
besides it is cheaper and far more satisfactory.

Should you have a fat pocket-book and at the same time a taste for
inventing and the sciences--these elements seldom go hand in mind--but
if they should get close together in your case I say, the right way to
make a model is to hire skilled men to do the work while you do the
thinking and the assembling in your private lab. By this process your
model will go forward rapidly and the work will be done in the best
fashion.

Before employing any one to work on your invention have him sign this
agreement:

EMPLOYEE’S PATENT AGREEMENT

 The undersigned, in consideration of his employment by Charles Basset,
 inventor, and in further consideration of the salary received by him
 for such employment, hereby agrees that all inventions and discoveries
 pertaining to the business of the said Charles Basset which may be
 made by him while in his employ shall become the property of the said
 Charles Basset.

 And further, he also agrees to assign to the said Charles Basset all
 applications made by him for _letters patent_ of the United States
 and elsewhere and all _letters patent_ that may be granted to him,
 covering such inventions and discoveries without further compensation,
 and

 That he will promptly, on conception of any patentable idea or
 invention, disclose the same to the said Charles Basset and on his
 request so to do will make application for _letters patent_ covering
 such inventions and discoveries;

 And further, that he will execute all other papers whatsoever that
 may be necessary to transfer to and rest in the said Charles Basset
 all the right, title and interest in and to such inventions and
 discoveries, it being understood and agreed that all expense incident
 to the securing of any _letters patent_ or application for patent
 shall be borne by the said Charles Basset.

  (Signed) HENRI FABRE.

  _Boston, Mass.,
  May 26, 1916._

  --_Brennan’s Handbook._

The plan of having a model maker do all of the work under your
direction may not appeal very strongly to you but after all, if you
lack the skill and the equipment needed for making your model, it is a
pretty good scheme.

Every large model making establishment has separate rooms fitted up
where each inventor can work on his own machine and this gives you the
privacy you demand and besides whenever you want a part made or changed
you have a skilled mechanic at your beck and call and a shop equipped
with the finest machine tools for him to use.

Nor need you be afraid that your invention will be _appropriated_,
which is a high-toned name for theft, by either the model maker or
his employers to whom you have entrusted your drawings, and for the
following reasons:

(1) Because any hint of such a thing as theft would ruin his business
for all time; (2) because 99 per cent. of all inventions fail to make
money for any one of 99 reasons and (3) because the model maker grows
rich making models for inventors while the latter mostly go broke; and
as far as the employees are concerned we must grant that they are as
honest, or even more so, than the average run of suffering humanity.

Neither are inventions apt to be stolen by patent attorneys for the
reasons cited above but after you have worked out your invention,
built a model and obtained a patent you are then in great danger of
being separated from the fruits of your genius and perseverance by
the professional promoter who makes it his business to finance the
invention and at the same time to feather his own nest; but more
about him a little later.

[Illustration: FIG. 68. SOME USEFUL JEWELERS’ AND MACHINISTS’ TOOLS]

A good way to safeguard yourself at the hands of model makers, if
you have any doubts about them, is to give different model makers
different parts to make and then assemble them yourself. While it takes
considerably longer to build up a model in this secret way still there
is a lot of satisfaction in this method of procedure.

[Illustration: FIG. 69. A SMALL HAND DRILL PRESS]


~The Tools You Need.--~To make a model of any description you need the
usual tools that are the handservants of every jeweler and machinist,
see Fig. 68, and you ought to have a small _drill press_, see Fig. 69,
and a _screw cutting lathe_, as shown in Fig. 70, if you can afford
these machines.

There are two or three tools that nearly everybody knows about and yet
which very few folks know enough about to use them. One of these tools
is the _vernier_ and another is the _micrometer_ and both are used for
_precision_ measurements.

[Illustration: FIG. 70. A FOOT POWER SCREW-CUTTING LATHE]

_The vernier_ is not, strictly speaking, a tool in itself but it is a
device that is applied to _scales_ which makes it possible to measure
small fractions of an inch much more easily and accurately than can be
obtained with the scale alone. The vernier is also used on calipers,
micrometers and other tools and instruments.

The vernier is a short scale which is fitted to and slides along the
edge of a fixed scale as shown in Fig. 71. The fixed scale is divided
into 10ths of an inch and the vernier, which is ⁹/₁₀ inch long, is
divided into 10 spaces.

Suppose now when you measure a part of your model that you move the
vernier over to the right so that the first mark of the vernier and the
first mark of the fixed scale are exactly in a line with each other,
then the vernier will have moved just ¹/₁₀ of a scale division which is
¹/₁₀₀ of an inch.

[Illustration: FIG. 71. A VERNIER FOR ACCURATE MEASUREMENT]

If the record marks of the vernier and of the fixed scale are exactly
even then the vernier will have moved ²/₁₀ of a scale division or ²/₁₀₀
or ¹/₅₀ of an inch, and so on. The fraction of the ¹/₁₀ inch that is
obtained with the vernier is added to the number of inches and the
fractions of an inch of the part which is measured. The vernier gets
its name from Pierre Vernier who invented it in 1631.

_The micrometer_ is a tool, or instrument, which will measure
accurately from 0 to 1 inch in thousandths of an inch. It is one of the
most useful measuring devices that has ever been invented and if you
are to build a model accurately you cannot get along without one. It is
shown in Fig. 72.

There are five parts to a micrometer and these are (a) the _frame_;
(b) the _anvil_; (c) the _spindle_; (d) the _sleeve_ and (e) the
_thimble_. The frame is held in the left hand, the object to be
measured being placed between the anvil and the spindle; the thimble
is turned by the thumb and finger of your right hand and the spindle,
which is fastened to the thimble, turns with it and moves through the
nut in the frame until the end of the spindle touches the object to be
measured.

[Illustration: FIG. 72. A MICROMETER FOR MEASURING THOUSANDTHS OF AN
INCH]

The measurement of the object is shown by the vertical lines on the
spindle and the horizontal lines on the thimble and both of which are
numbered. They are really a form of vernier.

To _read_ the micrometer, that is to find the measurement of an object,
you have only to multiply the number of vertical divisions which you
can see on the sleeve by 25 and to this add the number of divisions on
the bevel of the thimble from the 0 line to the line which coincides
with it, that is, comes even with the long horizontal line on the
sleeve. It is easy to learn to read a micrometer by taking one in your
hands, making a few measurements and following the above instructions.

The _wire gage_ is a circular piece of flat steel a little larger than
a silver dollar and it is used to find the numbers of, and to measure
the sizes of, wires. There are 32 slots cut in the edge each ending in
a hole and numbered from 5 to 36 as shown in Fig. 73.

[Illustration: FIG. 73. A STANDARD WIRE GAGE]

To find the number of a certain sized wire slip the latter into the
slots until you find one into which it will just pass snugly and the
number of the slot will be the number of the wire. On the reverse side
of the gage will be found the sizes of the wire in decimal fractions of
an inch.

[Illustration: FIG. 74. SOME USEFUL STOCK MATERIALS MADE BY AUTOMATIC
MACHINERY]

There are a number of different wire gages but the _American Standard_
or _Brown_ and _Sharpe_, or _B and S_ as it is called for short, is
the one mostly used by machinists in the United States.

Other useful gages are for the measurement of wood and machine screws;
for finding the pitch of screws; for measuring the inside of tubes,
holes, etc., and for measuring the outside of rods, tubes, etc. These
tools and all others used by jewelers and machinists can be bought
wherever tools are sold.


~Buying Materials.--~Many inventors waste time and sacrifice accuracy
in making, or trying to make, wheels, gears, threaded rods, nuts,
binding posts, contact points, switch levers and blades, hard rubber
knobs, handles and other parts.

Now all of these things and hundreds of other parts can be bought
ready made of model makers, gear works and dealers in hardware, model
aeroplanes, electrical and wireless apparatus. And before you begin
a model of any kind you should get catalogues from all of the supply
houses you see advertised. Fig. 74 shows quite a number of parts you
can buy ready made.


~About Making Patterns.--~Very often though you will have to make a
special part out of metal or have it made. Like everything else there
is a _best way_ to do this.

Suppose you need a _standard_ something like that used for a telegraph
sounder, as shown in Fig. 75. To saw and file out a solid piece of
brass would not only take a long time but it would prove a very tedious
job; and this is also true of many other parts you will need in the
course of making your model.

The best way is to make a pattern of wood of the desired part, take
it to a brass, or iron, foundry and have it cast. It is easy then to
smooth it up with a file or to _machine_ it in a lathe, or shaper, and
_lacquer_ it when it will look like a mechanic’s job.

[Illustration: FIG. 75. A STANDARD FOR A TELEGRAPH SOUNDER]

It is nice and easy work to make a _wood pattern_, that is to cut out
of wood the needed part of exactly the size and shape you want the
finished casting to be. The wood for your pattern should be pine or
poplar and thoroughly seasoned. A scroll saw frame will come in handy
for sawing out small patterns.

Where two pieces of wood are to be fastened together a good glue should
be used. After the pattern is built up file out the uneven places
with the kind of files made for scroll-sawyers’ use. When this is done
smooth up the pattern with medium fine sandpaper and finish it with
very fine sandpaper.

Should any holes or cracks show in the pattern after it has been
sandpapered fill them up with _putty_; and, last of all, give the
pattern a couple of coats of _shellac varnish_ or rub _graphite_ into
it all over to keep it from sticking to the mold. Your pattern is now
ready to be cast in metal.

[Illustration: FIG. 76. POURING A MOLD]

A pattern, if it is complicated, should be made by a skilled pattern
maker for it must be made in a certain way so that it will _draw_ from
the mold easily and without injury to the latter and leave it perfectly
smooth.


~Casting in Iron and Brass.--~Somewhere above I said that a pattern
should be the exact size you want the finished casting to be but as a
matter of precise statement iron, brass and nearly all other metals
shrink when they are cooling and so the pattern must be a trifle larger
than the exact size you require and you must also allow for filing and
machining. (See Fig. 76.)

As iron shrinks about ¹/₁₀ of an inch to a foot, brass shrinks ⅕ of
an inch to a foot and steel and aluminum shrink about ¼ inch to the
foot you must allow this much for shrinkage in making your patterns.
Type-metal is an alloy which expands on cooling and this is a useful
thing to know. You will find a formula for making it in _Appendix L_,
and all of the _appendices_ from A to N contain detailed information on
a variety of subjects that should be very helpful when you are making
your model.




CHAPTER VI

HOW TO PATENT YOUR INVENTION


With your model in such shape that it shows what your invention is and
what it will do you are ready to apply for a _patent_, or _letters
patent_ as it is technically called, by those versed in the art.


~What a Patent Is.--~The term _letters patent_ comes from the Latin
_litteræ patentes_ which means open or disclosed, as against the French
_lettre de cachet_ which means closed or secret.

A letters patent, or patent as it is called for short, is exactly what
its name implies and that is a disclosure of your secret and for this
disclosure of a new and useful invention on your part the government
agrees to give you a _monopoly_, that is the sole right to make, use
and sell it as you please for a term of 17 years.

But the government does not live up to its agreement with the inventor
and the invention and patent for it are never securely yours until it
has been tested in the United States Supreme Court and its judges have
handed down their opinion in your favor. But since there is no better
protection than a patent at the present time of course you will have to
get one.


~Choosing a Patent Attorney.--~The next hardest thing to do after
making a working model of your invention is to get a _patent attorney_
to take out a patent for you.

I don’t want to infer by this that it is hard to find a patent attorney
for on the contrary they are as numerous as sharks in the sea and
twice as voracious, but a patent attorney who really understands his
business and will take an interest in your affairs is as scarce as a
_pseudotriakis microdon_,[3] unless you are backed by unlimited funds,
and then you _may_ get service.

It is a strange thing but just as soon as you begin to work on an
invention you will see in every weekly paper and magazine you pick up
the advertisements of patent attorneys and usually they are located in
Washington “in a building across the street from the patent office” or
in a building up the street from which the patent office can be seen.

Their _ads_ are very alluring as they often offer as an inducement to
make a _free search_, as explained in Chapter III; to keep your signed
_evidence of conception_ in their fire-proof safes, and to refund your
money if they do not get a patent for you. That these knights of the
patent bar will do all they say there is not the slightest doubt and
that is just where the rub comes in.

Any patent attorney can get a patent allowed on nearly anything if the
claims are written _narrow_ enough but when it is granted it won’t be
worth the paper it is written on and the patent examiner knows it, the
patent attorney who gets it knows it and you will know it too after you
have spent your good money for it but then it is too late. A patent
attorney of this kind is a good one to keep away from.

The safest way is to go to a patent attorney in your own city or get
into communication with one who lives nearest to you and engage him to
prepare your patent application and _prosecute_ it in the patent office.

And whatever you do make him agree to a _flat-rate_, that is to name a
fixed sum which you are to pay him for his services including the fee
for filing the application in the patent office. The _filing fee_ is
$15 and the lowest fee I ever heard of any patent attorney taking to
prepare a case and seeing it through the patent office was $30, which
with the final government fee of $20 makes a total of $65; and from
this his fee will go on up to whatever amount he thinks he will be able
to get you to pay.

Should you happen to secure the services of a so-called really
high-grade patent attorney you will not be likely to induce him to
make a flat-rate for this is poor business on his part. Instead the
way a better class patent attorney will deal with you, as a rule, is
to induce you to start in by giving him a _retainer_ of say $25 or
$50; then from time to time he will send you statements and as you pay
them the amounts he demands will grow larger and the statements more
frequent until by the time the patent is granted, you will have paid
in enough to buy him a fur-trimmed overcoat or a Ford automobile.

The amount thus spent is not of so much consequence but what does
matter is that where you and your patent attorney have no definite
arrangement as to fees he is tempted, and in many cases yields to the
temptation, to string the patent application along over a period of
months if not of years, when if it had been followed up right along it
would have been granted to you in a much shorter time.

The moral of this un-fable is to hold your patent attorney down to a
fixed price right in the beginning and have him write you a letter
stating the amount he is to get and the work he intends to do for it,
and this will serve as an agreement.

The above are only a few of the bubbles in the patent system and to
warn you of them all would take a book as large as an unabridged
dictionary. The best advice I can give you is to study your invention
from every angle, look up the state of the art in all its phases and
then with a full understanding of just what you are entitled to write
down all the points you want your patent to cover.

Now catch your patent attorney, being sure he does not catch you first,
and to _parodize_ a _caption_[4] of the immortal Roosevelt, _fear the
patent office examiner and take your medicine_.


~Applying for a Patent Yourself.--~To get even a small part of what
you are _legally_ entitled to in a patent you should write to the
_Commissioner of Patents_, Washington, D. C., for a copy of the _Rules
of Practice in the United States Patent Office_, see Fig. 77, which
will be sent to you free of charge. Read this booklet through not
once, but many times, or at least until you understand everything in
it for it will help you mightily in the preparation of your _patent
application_ and the prosecution of it.

[Illustration: FIG. 77. RULES OF PRACTICE OF THE PATENT OFFICE]

You will learn from the _Rules of Practice_ that you as an inventor
may apply for your own patent and act as your own patent attorney in
prosecuting it. And after you have learned the _rules_ by heart you may
feel that since you know more about your invention than any one else
you can make the drawings and write the specification and claims as
well or better than the average patent attorney.

But you should think twice and count ten with your eyes shut before
you conclude to do this rash thing. Why? Because the patent office
will not accept your _drawings_ unless they conform exactly to certain
rules; your _specification_, which means the description of your
invention, must be written in a certain way, and the _claims_, which
are the very vitals of the whole patent, must be drawn with exceeding
care for while nothing of value must be left out it is even worse to
write in too much as this limits your claims.

Besides these reasons it grieves a patent office examiner whenever a
mere inventor comes forth and files his own patent application and
conducts his own case even if he has the ability to do so and when it
comes to _amending_ his claims he will find the hurdles are rather
higher to jump over than he at first supposed.


~Applying for a Patent through a Patent Attorney.--~Taking all these
things into consideration my advice to you is to retain a patent
attorney to prepare your case and see it through the patent office, and
then you want to be prepared to watch every move he makes--that is to
say when he has drafted your application, get a copy of it and go all
over it yourself taking plenty of time to do it in; and then go over it
with him covering every detail.

In due time after your application has been filed the patent examiner
will send a _letter_ to your patent attorney in which he notifies you
that some, if not all of your claims, have been _rejected_ and _citing
references_ to other patents chiefly to show that your claims lack
newness and novelty.

The next step is taken by your patent attorney who _amends_ the
specification and claims to meet the objections raised by the patent
examiner. Here again you should know how and where your claims are
affected and you should aid your patent attorney to determine whether
or not you should insist on your claim being allowed to stand as it is
written or to so change it that it will satisfy the patent examiner.

It must be clear now that if your patent attorney is permitted to keep
on changing your claims to meet every rejection of the patent examiner
instead of fighting them out by the time the patent is granted it will
have degenerated into merely a scrap of paper. Hence if you leave the
whole case to the ability and judgment of your patent attorney you can
be reasonably sure that your $65 or $250 or whatever sum you have paid
him for obtaining your patent is as good as thrown away.


~What You May Patent.--~In all of the foregoing text I assumed that
your invention consisted of a machine but according to rule 24 of the
_Rules of Practice_ a patent may be obtained for _any new and useful
art, machine, manufacture or composition of matter, or any new or
useful improvement thereof_.

Since all mechanical movements have been invented and all necessary
electric currents have been discovered and enough chemical elements
are known it may seem on first thought quite impossible to invent
or discover anything either new or useful, yet the patent office is
granting patents at the rate of about 125,000 a year.

The way inventions are made is by forming new _combinations_. Just as
there is no practical limit to the number of new words that could be
formed by new combinations of the letters of the alphabet, so there
is no practical limit to the new machines that can be invented by
novel combinations of the mechanical movements, with the result that
something can be done that had not been done before, or that something
is done in a better, cheaper and easier way than it had ever been done
before. And the same is also true of combining electro-mechanical
devices and of combining chemical elements.

Inventing means that you are clever in combining certain movements,
devices and chemicals in a new way to produce a certain result
which may or may not have been done before, and so it is the new
_combination_ of things that you really get a patent on.


~Looking Ahead.--~It must be plain now from what has been said that
when you have completed your machine, or product, or compound, all your
inventive efforts will be in vain unless you go over every part with
the utmost care and try to think out how it could be changed or done in
some other way by some one else and so make your patent worthless, and
your hard efforts wasted.

What you should do, though it is easier to advise than it is to
accomplish, is to so word the claims of your patent application that
they will broadly cover not only your particular combination but every
other form of it. Finally should your invention be one of considerable
magnitude and great importance you must keep working on it all the
time and making improvements and covering the last named with patents
or the other fellow--the patent thief--will get you sure, and often he
will do it anyway.


~What a Patent Consists Of.--~All through this chapter the words
_drawings_, _specifications_ and _claims_ are used and now suppose we
find out just what is meant by them.

Every patent application is made up of five parts and these are (1)
the _petition_; (2) the _drawings_; (3) the _specification_; (4) the
_claims_, and (5) the _oath_. The petition and the oath are separate
papers and do not appear in the patent when it is granted. The
drawings, specification and claims form the patent when it is granted.

_The form of petition_ by a sole inventor is as follows:

 _To the Commissioner of Patents:_

 Your petitioner, ..............., a citizen of the United States and
 a resident of ......, in the county of ...... and State of ......
 (or subject, etc.), whose post-office address is ........, prays
 that letters patent may be granted to him for the improvement in
 ............, set forth in the annexed specification.

 Signed at ........., in the county of ....... and State of ......,
 this .... day of ......, 19..

Other forms by joint inventors, etc., will be found in the _Rules of
Practice_.

[Illustration: FIG. 78. A PAGE OF DRAWINGS FOR A WIRELESS TELEPHONE ARC]

_The drawing_ or drawings come first and these are made on white paper
the thickness of Bristol board and the size of the sheet must be
exactly 10 by 15 inches with a line drawn 1 inch from the edges all
round making the _sight_, that is, the space in which the drawings are
placed, exactly 8 by 13 inches. A reduction of a sheet of drawing for
the author’s _revolving arc_ for his wireless telephone is shown in
Fig. 78.

The drawing or drawings, there may be one or more on a page and several
pages if needs be, must show every detail covered by the specification
and claims. The drawings may be made in _isometric perspective_ as
described in Chapter II, or plan or elevation views can be used, or
both of these kinds of drawings as long as the pictures show exactly
what the invention consists of and how it works. Usually the different
parts are numbered and these are referred to in the description of the
invention.

Should your invention be an electrical one, then a diagram of the
apparatus formed of symbols (see Chapter II) should be used.

The _specification_, the front page of one of which is shown in
Fig. 79, is that part of a patent which describes your invention or
discovery and it should be as full and as clear as you and your patent
attorney can make it and yet it must be concise and to the point.

Don’t try to hide, or keep anything back for should the patent be
granted to you under these conditions it will be without value if it
should ever figure in a suit. If you are not willing to make every
detail known it is better not to apply for a patent at all.

[Illustration: FIG. 79. SPECIFICATION OF ONE OF MR. COLLINS’ PATENTS]

[Illustration: FIG. 80. THE CLAIMS OF THE SAME PATENT]

The _claims_, a few of which shown in Fig. 80, are the all important
part of every patent and these must be clearly, cleverly and carefully
worded so that if you ever have to fight an infringer in court your
claims will be found to cover exactly the details of your invention and
this will make it harder for the other fellow’s expert to misconstrue
them.

_The oath._ When you apply for a patent you must affirm, or make oath
that you believe yourself to be the “first and original inventor
or discoverer of the art, machine, manufacture, composition or
improvement” for which you ask a patent. A form of oath to accompany a
patent application is as follows:

  ............ ............}
  ............ ............}_ss_:

 ........ ........, the above-named petitioner..., being sworn (or
 affirmed), depose ... and says ... that .......... citizen ... of
 ....... and resident ... of ......, that .... verily believe ......
 ....... to be the original, first and ...... inventor ... of the
 improvement in .......... described and claimed in the annexed
 specification; that ........ do ... not know and do ... not believe
 that the same was ever known or used before ..... invention or
 discovery thereof, or patented or described in any printed publication
 in any country before ...... invention or discovery thereof, or
 more than two years prior to this application, or in public use or
 on sale in the United States for more than two years prior to this
 application; that said invention has not been patented in any country
 foreign to the United States on an application filed by ........
 or ...... legal representatives or assigns more than twelve months
 prior to this application; and that no application for patent on
 said improvement has been filed by ...... or ...... representatives
 or assigns in any country foreign to the United States, except as
 follows: ...........

  Inventor’s full name: {................ ................
                        {................ ................

 Sworn to and subscribed before me this ................ day of ......,
 19..

 [SEAL.]

  ................ ................
  [Signature of justice or notary.]
  ................ ................
  [Official character.]

A good way to get an idea of how a patent looks and reads is to send 5
cents in coin to the Commissioner of Patents, Washington, D. C., with
the request that a copy of patent No. 814,942 be mailed to you.


~While Your Patent is Pending.--~In a month or six weeks after your
application has been sent in to the patent office your patent attorney
will receive an official reply, or _action_ as it is called, and don’t
be surprised and don’t let it worry you if you find that all your
claims have been rejected by the examiner.

He will state his reasons in his letter for the rejection and give
references, which are usually other patents, to show that some other
inventor has _anticipated_ you and that your claims are neither new nor
novel.

Your patent attorney must then either _amend_ the claims, that is
reword and change them if you and he think the examiner is right, or
else in your letter of amendment, you must show the examiner where and
why he is wrong. At any rate you must satisfy his objections.

By the time your amended application reaches the examiner and he
again acts on it he will have dug up a lot more of references from the
_archives_ of the patent office; and then you and your patent attorney
can go all over the amending process again.

After having gone through with this sort of thing a dozen or more times
and covering one or more years--I have just had a patent allowed that
had been pending for nearly seven years--you and your patent attorney
and every one else that may be interested with you will be sore unto
death over the delays--that is everybody except the patent examiner and
he thrives upon the inventor’s discontent.


~Interference.--~As if all these trials and tribulations are not enough
it often occurs in the course of a pending patent that some one applies
for a patent on the same, or nearly the same, invention as your own.

When this happens the patent examiner declares an _interference_, the
purpose of which purports to be to show which applicant is the first,
or real inventor.

When interference proceedings are begun you will have to make under
oath a _preliminary statement_ showing when you first conceived the
idea of your invention, when you first explained it to some one else,
when you made your first drawings of it and when you constructed a
model of it; all of which shows the importance of keeping a record of
each step of your invention and of having them frequently attested.

These sworn statements by yourself and your opponent are passed upon
by the _examiner of interferences_ and if either you or your opponent
are not satisfied with his findings either one of you may take an
appeal to the _board of examiners-in-chief_, and from this board to the
_Commissioner of Patents_ and finally, to the _Court of Appeals of the
District of Columbia_.

And don’t forget that all these proceedings and appeals are as meat
and drink to the patent lawyers and that you and your opponent are
contributing _all_ of the money in exchange for a lot of red tape that
ought to be abolished.


~When Your Patent is Granted.--~But some bright morning you will
receive a government document printed on vellum, showing a picture of
the patent office at the top and signed by the Commissioner of Patents
at the bottom, the whole being tied together with a pair of baby blue
ribbons and to the ends of which is affixed a red seal bearing the
imprint of the _Patent Office of the United States of America_, and at
last you have your patent. The front cover of a patent granted to your
humble servant is shown in the frontispiece.


~After Your Patent is Granted.--~But after you have this valuable
grant conferred by the government in your possession which is alleged
to give you a monopoly on your invention for a period of 17 years you
have only started on your career as _patentee_, for about the next
thing that will happen, if your invention is worth anything and you are
manufacturing and marketing it, you will find that some one else is
making and selling exactly the same thing.

He may or may not have a patent on the article or machine and it--the
patent--may or may not be remotely like yours but this doesn’t in
the least matter, he will keep right on working your invention and
_infringing_ your patent until you will either have to sue him, or
continue to lose large profits that should be yours and perhaps be
driven out of the business entirely.

So, of course, you see your patent attorney and he, of course, advises
you to begin suit at once. It sounds to your abused ears like right and
justice but it means an outlay of much time and more money than you
could begin to think of unless you have been through the mill before.

This time you will have to engage _patent counsel_--no mere patent
attorney will do if you are to win--and you must have _experts_ to
testify for you and your _patent cause_--it is no longer called a
patent case--and testify against your opponent. The only limit to
the fee that able patent counsel will demand and collect is fixed by
your bank account while $100 per day is the usual fee of a _technical
expert_ though like his legal ally he will ask and get much more if you
can afford it.

After long months of drawn out preparation and taking testimony and
quibbling you will find, if your legal talent is the smartest, that
the patent granted you by the patent office has been sustained by the
court. Such a decision may put the other fellow out of the business but
it isn’t once in a thousand causes you can collect damages when you
win. And from this you will observe that the business of the patent
office is not to give you a monopoly but simply to grant you a patent
and as to its validity the courts must settle that.

[Illustration: FIG. 82. THE UNITED STATES PATENT OFFICE, WASHINGTON, D.
C.]


~About Paper Patents.--~A _paper patent_ is a patent that has been
granted by the patent office for a new and novel idea that has never
been worked out in practice.

For instance, suppose you get an idea for an invention or an
improvement that seems a good thing especially after you have looked
up the state of the art, and when you draw it out on paper it seems
certain to work. And let’s suppose that for the want of time or money
you are not able to experiment on, or build a model of it; and you have
fears that by the time you could build the actual machine some one else
may have applied for a patent on the same thing.

Of course, you feel you want to protect the idea and to do so you
proceed to apply for a patent and in its own good time the patent
office grants you one. You have then a thing called a _paper patent_
but you haven’t got the machine, or device or composition to back it up
with.

Well, it’s just like writing a book about a trip to the moon; you know
how far from the facts your guesses would probably be and it is the
same thing with getting a patent before you have made the experiments
or built a model.

A paper patent is not usually worth the time and money you spend on it
because it lacks backbone, but they have caused many real inventors a
deal of trouble and expense in fighting them.




CHAPTER VII

MAKING YOUR INVENTION PAY


After reading what has gone before you may well conclude that an
inventor’s life is not a happy one but let me remind you that whatever
road you take to seek fame and to win fortune you will find it just as
full of petty strife and big difficulties.

In sooth inventing is one of the easiest and pleasantest pursuits in
which you can engage to make a good living and many inventors who were
as poor as Job’s turkey when they began to think up new ideas and
concoct useful schemes now have their thumb-nail biographies in _Who’s
Who_ and live on the fat of the land.

And you can do the same thing too if you have a real invention and a
lot of native shrewdness. Yes, to be a money-making inventor you must
have inventive ability plus business ability, or rather the other way
about, for business ability counts for more in the game of success than
inventive ability.

There are hundreds of inventors of the highest type who are
comparatively poor men for the lack of business ability while many
others, like Edison, all round inventor, Westinghouse, inventor of the
air brake, and Eastman, inventor of the kodak, have made fortunes that
run up into the millions because they are first, last and all the time
hard headed business men. And you must be a business man too if you
want to make money out of your invention.


~How to Raise the Initial Funds.--~By _initial funds_ I mean the first
money. It is easy to tell an inventor who has a rich dad or a bank
account in his own name how to finance his invention.

But mine is a harder task in that I am taking it for granted you are
like 999 out of every 1000 inventors and that you have little or no
money, are fired with ambition and that you have a big idea.

Assuming that this is the precise state of affairs let’s go back to
where we started from in Chapter I, that is to the last part of it
where you had drawn out your invention on paper, written a description
of it and had some of your friends put their signatures to it.

Should your invention seem to your friends to have merit it will take
but very little urging to get one or more of them to furnish whatever
amount of money you think will be needed to carry on the experiments or
to build a working model. Of course you will in turn have to agree to
give him, or them, a certain small interest in your invention, and this
is fair exchange for you are putting up your brains against their money.

If your invention is a small one and but little money is needed to
develop it into a _marketable_ product a 5 per cent. interest is enough
to give those who back you for taking the risk. A 10 per cent. interest
is ample to offer for sufficient funds to develop a more complicated
invention.

This will leave you a 30 or 35 per cent. interest to sell to others
later on, when you have a working model and your patent is granted,
to furnish the capital necessary for equipping a factory to make the
device and to provide funds to market it--that is if you work out a
plan along these lines.

But take my advice and keep a 55 per cent. interest in the invention
for yourself; otherwise the control of it is taken out of your hands,
and whenever it suits those who hold the controlling interest to freeze
you out they will do so with pleasure.

By using the following form you can save the expense of having a lawyer
draw up one for you and moreover you can also be sure there is no
_joker_ in it.

 FORM OF AN INTEREST AGREEMENT

 _Memorandum of Agreement_ made this _third_ day of _September, 1916_,
 between WILLIAM FRANKLIN, of Peoria, Illinois (inventor), and GEORGE
 WILSON, of Peoria, Illinois, WITNESSETH: That

 WHEREAS, the said _William Franklin_ has invented what he verily
 believes to be a new and useful improvement in _gas engines_ and for
 which he will apply for letters patent of the United States, provided
 certain tests which he shall make shall work out satisfactorily, and

 WHEREAS, the said _George Wilson_ is desirous of obtaining an interest
 in the net profits arising from the sale or working of the said
 invention after the said letters patent of the United States has been
 granted:

 NOW, THEREFORE, in consideration of the premises and of One Dollar
 to each in hand paid by the other, the receipt whereof is hereby
 acknowledged, the parties hereunto do covenant and agree as follows:

 FIRST: That the said _William Franklin_ for and in consideration of
 the payment of $1000 by the said _George Wilson_ will pay to the said
 _George Wilson_ 5 per cent. of all net receipts accruing in any manner
 from the sale or working of the said invention and patent during the
 term of its life.

 SECOND: That the said _George Wilson_ shall pay to the said _William
 Franklin_ the sum of $1000 which shall be applied to the making of a
 _model_ of the said invention and to securing a letters patent of the
 United States for the same.

 It is understood and agreed that this instrument shall bind the
 parties hereto, their heirs, executors, administrators, successor or
 successors or assigns.

 IN WITNESS WHEREOF, the parties hereto have hereunto interchangedly
 set their hands and seals the day and year first above written.

  IN THE PRESENCE OF

  _Charles Howard_
  as to the Inventor.

  _John D. Prentiss_
  as to George Wilson.

  _William Franklin_ [L. S.]
  _George Wilson_ [L. S.]


~About an Interest in a Patent.--~There is a big difference between
assigning an interest in your invention and assigning an interest in
your patent.

Many an inventor assigns an interest in his patent either before or
after it is granted to some one who will advance the needed money.
But this is a thing you should never do for after having made such an
_assignment_, however small the part, the person who owns it can make,
use or sell the invention which the patent covers, as he chooses, just
as though he owned the whole patent and you can neither stop him nor
even sue him for damages.

You can, of course, make, use and sell the invention covered by the
patent too but usually it is the other fellow who gets the best of the
bargain.


~Royalties, Shop Rights, etc.--~After you have built a working model
and obtained a patent on it there are many ways of making money out of
your invention.

One is to sell your invention and patent outright; another is to sell
_shop-right licenses_; another is to have some manufacturer give you a
_royalty_ on each machine or device he makes and sells, and yet another
way is to sell _territorial rights_, that is the town, county and state
rights to manufacture your invention. Forms of agreements for all of
these deals will be found in the _Rules of Practice_ of the United
States Patent Office.

Besides the above arrangements you can go into partnership with some
moneyed man, or interest, and finally a good plan, where a large amount
of capital is required to build a plant and start a business, is to
form a company, or _corporation_ as it is called.


~Forming a Partnership.--~Now that you have your model completed and
your patent granted you will of course want to begin _commercial
operations_ immediately, and let’s suppose you think better of forming
a partnership than any of the other above named plans.

There are a hundred ways to secure a partner, or _business associate_
as the sharer of your fortunes is called, but it is a mighty hard thing
to get a satisfactory one. A favorite way to enlist capital and one
that is often resorted to by inventors in large cities is to advertise
in the newspapers under the head of _business opportunities_.

An advertisement of this kind may put you in touch with the man you are
looking for but it will also bring you a lot of curiosity seekers, riff
raff and other undesirables who come generally with a view of inducing
you to part with your money rather than to invest any of their own.
This is also true of the so-called _brokers_ who advertise to procure
working capital for meritorious inventions.

One of the best ways to secure a partner who has the necessary capital
and requisite business ability is to arrange to show your invention in
operation and then invite your moneyed neighbors and the business men
of your town, though you may not know the latter personally, to call
and see it; and they will call and get interested if they believe in
its possibilities for they are as anxious to make more money as you
are to make a little of it, and they are keen to the fact that great
fortunes have been built up out of simple as well as complex inventions.

This method of showing your invention to your towns-folk, either
individually or collectively, is the safe way to get one or more
good, substantial men interested in your proposition and to lay the
foundation of a paying business.


~Where the Promoter Comes In.--~There are promoters and promoters; by
which I mean that there are various sorts of promoters and then some.

A _tin-horn promoter_ is an unprincipled fellow of some ability who
secures an _option_ on a patented invention, or on the stock of a
company based on an invention, and exploits it for all he is worth to
his own profit and without regard to the inventor or the stockholders.
The chief business of a tin-horn promoter is to secure control of the
entire stock issue of a company, sell it at inflated prices, pocket 90
per cent. of the proceeds and either doctor the books or disappear then
altogether. Steer clear of the tin-horn promoter.

An _ordinary promoter_ is merely an agent who acts as a go-between for
the inventor and people with money to invest and by his enthusiasm
brings them together for the good of the cause. A _real promoter_
is a genius who possesses both business ability and the necessary
wherewithal to start, _accelerate_ and carry on any kind of an
_industrial_, _financial_ or _commercial_ enterprise.

You will meet the promoter in one shape or another as soon as it
becomes noised around that you have an invention of merit. The ordinary
promoter will be of assistance to you at any stage of the invention
where experiments are still to be made and the patent is yet to be
granted. He may also prove of service after the _preliminary_ work is
done in securing for you a real promoter.

On signing contracts with the latter he will relieve you of all the
cares of starting the business or of starting a company to start the
business. And if you are not shrewd and careful and know just what
he is doing and you should fail to have a hard and fast contract he
will not only be likely to relieve you of the business cares but of
everything else you may hold dear and sacred in this world.

An ordinary promoter will ask about 25 per cent. of whatever money he
brings in for your use in developing the invention and a certain small
interest--1 to 5 per cent.--in the company that exploits it. The real
promoter wants and usually gets a working agreement of 50 per cent, of
whatever profits there may be made out of the invention. If possible
you should hold a 55 per cent, interest for this will give you the
whip-hand and will save you much trouble in the end.

Few promoters though will agree to such a division and about the only
way you can keep the controlling interest is to organize a company and
manage it yourself but this takes business ability of quite a high
order.


~What a Stock Company Is.--~A _company_ is a number of persons who
band themselves together for business purposes. A _stock company_, or
_stock corporation_ to call it by its proper name, is a company whose
_capital_ is represented by _shares_ and which is held either in the
_treasury_ of the company, or by persons who buy the shares.

Three or more persons may form themselves into a stock company for any
industrial purpose in the State of New York. A stock company must be
_incorporated_, that is _legally formed_, under the laws of a State
and different States have different laws. A copy of the corporation
laws of any State may be had free of charge by applying to the
Secretary of State.

[Illustration: FIG. 83. CERTIFICATE OF INCORPORATION]


~How a Stock Company is Organized.--~Suppose, now, you and two other,
or more persons want to organize a stock company under the laws of the
State of New York for say $10,000, although the value which you, and
those interested with you, place on your invention and patent may be a
great deal more.

Then you and the others make, sign, acknowledge and file a _certificate
of incorporation_, a reproduction of which is shown in Fig. 83 (see
outfit necessary for a Corporation), and this must contain: (1) the
name of the proposed company; (2) the purpose for which it is formed;
(3) the amount of the _Capital stock_ (which means the entire amount
of the stock, for which the company is capitalized and which, let’s
say, is $10,000); (4) the number of _shares_ of which the capital stock
is to consist (each share of which must not be less than $5 nor more
than $100 and the amount of actual capital must not be less than $500
in cash with which the company is to begin business) and the amount of
cash must be stated; (5) The certificate must also contain the name of
the city, village, or town, in which its principal business office is
to be located; (6) its duration, which you can put at 50 years; (7)
the number of its directors which must be not less than three; (8) the
names and post-office addresses of the directors for the first year,
and (9) the names and post-office addresses of the subscribers to the
certificate of incorporation and a statement of the number of shares
of stock which each agrees to take in the company. A _certificate of
incorporation blank_ ready to fill in can be bought for 10 cents of
stationers who deal in law books and forms.


~The Fees of the State.--~The fees for incorporating a company are
payable in advance at the Secretary of State’s office and these are for
(a) filing the certificate of incorporation $10; (b) recording it,
15 cents per folio of 100 words; (c) a _certified copy_, if you want
one, 15 cents a folio and $1 additional for the seal affixed to it;
(d) the _organization_ tax, payable _direct_ to the State Treasurer
_in advance_ is 1-20th of 1 per cent, on the amount of the capital
stock, which on a capitalization of $10,000 would be $5, and (e) all
personal checks for fees or taxes must be _certified_, that is to have
the paying teller of the bank your check is drawn on write _good_ on it
together with his name.

[Illustration: FIG. 84. STOCK CERTIFICATE]


~Outfit Needed by a Corporation.--~To begin business with after you
have received your certificate of incorporation you must have:

(1) A _minute book_ in which to record the proceedings of the
directors’ and stockholders’ meetings. A minute book with _printed
forms_ can be obtained which makes it easy to record the minutes
accurately.

(2) A _stock certificate book_; suppose your certificates, or
shares, have a _par value_ of $100 then you will need a book of 100
certificates to equal $10,000. A stock certificate is reproduced in
Fig. 84.

(3) A _book of account_ is required by the New York State _transfer
tax_ law where companies are doing business in the State, and _transfer
agents_ must also have one to show every transfer of stock. Neglect to
keep this book imposes a heavy penalty.

[Illustration: FIG. 85. A SEAL PRESS]

(4) The New York _transfer law_ also requires New York companies to
keep a _stock transfer book_ which shows when shares, or certificates,
are sold, or transferred, by one person to another.

(5) A stock ledger is also needed by every corporation to enter the
stock transactions of each day in. A combination book with all of the
three last named can be bought ready for use.

(6) A _corporate seal_, which is an embossed impression of the name of
the company, see Fig. 84, is made by a _seal press_ as shown in Fig.
85, and this is also required by law. The whole outfit above described
for incorporating and maintaining a company can be bought for the small
sum of $10 or less of the Brown-Green Company, 48 John Street, New York
City.


~How a Stock Company is Operated.--~When you receive your certificate
of incorporation you can then call a meeting of the _directors_ (named
in the certificate of incorporation) or _board of directors_ as they
are called. At this first meeting the directors elect the _officers_,
that is a president, a secretary and a treasurer.

The president then takes the chair and the secretary writes down all
the minutes of the business transacted at this and subsequent meetings.
The first business that will come before the directors after the
election of the officers is to make the stock of the company _full
paid_. To do this you must turn your invention and patent over to the
company in exchange for the full amount of the stock the company is
capitalized for, say $10,000. In other words you sell your right, title
and interest in the invention and patent for $10,000 worth of stock,
which is all of it.

Next you turn back into the treasury of the company 45 per cent, of the
stock and keep 55 per cent. for yourself. The 45 per cent. of the stock
in the treasury, which is called _treasury stock_, can then be sold
at its _par value_, that is full value, which is $100 per share or at
any smaller price the board of directors may agree upon. The sale of
the treasury stock gives the company the capital it needs to start the
business and to keep it moving until it becomes self-supporting.

If $4,500 is not enough money to finance your company then capitalize
it for whatever amount you think will be needed and add about 50 per
cent. more to it. You can incorporate a company for $100,000 just as
easy as you can for $10,000, but this is a matter you and your friends
should consider most carefully.

Should you at any time sell more than 5 per cent. of your holdings,
that is of the stock you own, the control of the company will pass out
of your hands and the other directors and stockholders will whip-saw
you as they like, if they can pull together, for the majority of the
stock will be in their hands.

The stock, or _securities_, as it is called, of a company can be sold
in a number of ways but the usual method is to sell it (a) by personal
solicitation, (b) through stock-salesmen, (c) have a broker take the
whole stock issue, and (d) by advertising. If your invention is what it
seems to be, your patent as good as the average patent, your company
capitalized for a moderate amount and the product looks good for making
quick sales and large profits you won’t find any trouble in placing the
stock with the moneyed people of your community.

Besides receiving 55 per cent. of the stock for your invention and
patent you should as the inventor and practical man be voted a salary
of $25, $50 or $100 per week to superintend the manufacturing end of
the business. Have a salary contract drawn up with the company in which
the amount you are to receive weekly and the length of time you are to
receive it is stated, and have it signed by the president and secretary
for the company.


~About Retaining a Lawyer.--~In all of your business dealings with
other people from the very beginning the safest way is to have the
advice and help of a _corporation_ lawyer and while he is keeping you
safe, whole and harmless from all damage be sure he doesn’t mulct you
while he is doing it.

A good way is to pay him a flat-rate for whatever advice he gives you
and the contracts he draws up for you. But if you can’t do this then
give him a 1 per cent interest in the net amount which you may receive
from your invention.

When you and your associates have decided on organizing a company the
usual and proper way is to retain a lawyer and have him take care of
the incorporation certificate, conduct the first meeting and open the
books, to the end that it may all be done right and in good legal form.




CHAPTER VIII

SOME HINTS ON MANUFACTURING


After you have formed a partnership or a company and have the coveted
capital to go ahead with the business, you and your associates must
consider two problems and the way you work them out will decide whether
your venture will lose money or _declare dividends_.


~The Problem of Manufacture.--~These two problems are the manufacturing
and the marketing of your product and in this chapter we will talk
about manufacturing it first and then take up the marketing end of it
in the next chapter, for while they are closely allied in a common
cause they have to be treated as entirely separate things.

In this respect a manufacturing concern is very like a human being in
that it has a brain and a body. You and those interested with you are
the brains of the organization and those who work for you, to the end
that profits may pile up for your benefit and behoof, form the body.

On your head, most likely, will fall the responsibility of turning out
a high-grade product at the lowest possible cost and to do this the
right way and to the best advantage you must begin at the beginning
and think and scheme out how you can obtain the best results with the
least outlay of time, labor and money.

There are many ways to start in manufacturing your product but the
_efficient_ way will depend on what you have to make, the number you
are to make and the amount of capital you have to do it with.


~Farming out the Work.--~In the beginning you will often find it
much cheaper, and hence more profitable, to give a contract to
some manufacturer--who has a big factory fitted out with thousands
of dollars worth of machine tools and a capable force of skilled
mechanics--for a given number of the articles, or machines, you want to
have made and delivered in and at a certain time.

By this arrangement there is no _initial_ time, effort or money spent
on buying machinery and getting a factory into running order, neither
is there the work and worry of keeping a shop force going and besides
you know exactly what each device will cost you when the lot is done
and delivered. Still this scheme is not one that appeals to many
inventors especially if they have, or think they have, a genius for
mechanics and shop management.

Another way to start operations in an economical manner is to have
some one or all of the parts of your invention done by outside
manufacturers, or _farm them out_ as it is called, and then assemble
the parts in your own shop. Scattered all over the United States are
shops and all sorts of factories where you can get a lower price
quoted on a certain part or parts made of wood, brass, rubber or any
other material than you could possibly make it or them for, in a shop
of your own in the beginning.

Of course the larger the quantity of a given piece you can order at
a time the lower will be the _pro rata_ cost, that is the cost of
each piece; for instance suppose a brass founder quoted you a price
of $1 each on a certain casting in lots of ten, he might scale the
price down to 50 or 60 cents each in lots of one hundred, and if you
ordered a thousand at a time you might _get_ the price down to 35 or
40 cents each. In figuring cost things like this must be taken into
consideration.

In many cases it is not the mere material put into, and labor put on
making a part that brings up the cost of the first lots but before the
part can be turned out a special _die_, or _jig_, or _fixture_ must be
made for duplicating the part and very often a special machine must be
designed and built for making a certain part. Such special tools and
machines are very expensive and their cost must also be reckoned with.


~Starting Your Own Shop.--~In starting your own shop the question of
what you are going to make and the quantity you intend to make will fix
very largely the kind of machinery, the floor space and everything else
you will need, nearly.

In this age of cheap electric power you can have an electric motor
installed, to run your lathes, drill presses, shapers and other
machines, almost anywhere you happen to be located. And besides it is
better, as a rule, to start and operate your plant in your home town.
For a shop on a small scale, wherever it may be, it is cleaner, less
troublesome and cheaper to use electric power than it is to use gas or
steam power.

Should you intend to operate on a very large scale it may then be to
your advantage to look up a place where there is water power, or if
your industry is one that calls for the large use of electricity you
would then be justified in moving to Niagara Falls, or some other place
where there are great hydro-electric plants.

The matter of being near to certain raw materials you need for
manufacturing, or to a market for your product is not one that you will
probably have to decide alone. Nor need the question of labor take
up your time for the wages of skilled machinists, electricians and
chemists are about the same throughout the United States, and while
rents are higher in large cities than in the towns and villages still
nearly one-half of the articles and machines made in the United States
are turned out in 100 of the largest cities.

One of the advantages of manufacturing in a large city is that you can
always get skilled labor and a great variety of materials on short
notice. Should your product be in the nature of gas or steam engines,
harvesting machines or automobiles you should locate your factory on
some navigable river, on the Great Lakes, or on a railroad line (with
a spur-track running alongside), in order to insure good and cheap
transportation.

When you rent or build a shop the main thing is to have plenty of
windows on every side and see to it that the ventilation is good and
the heating system is adequate. There is no economy in making men work
with poor light, bad air and in a cold place.


~Buying Machine Tools.--~Having secured by lease or by purchase a shop,
or factory suitably located your next effort will be directed toward
equipping it with the proper tools and machinery.

Besides the usual machinists’ hand tools you should buy (1) a _gas
furnace_; (2) a _grinder_; (3) a _plain lathe_; (4) a _screw cutting
lathe_; (5) a _drill press_; (6) a _planer_; (7) a _shaper_; (8)
perhaps a _milling machine_, and (9) a _buffer_. Several of each of
these kinds of machines may be needed.

[Illustration: FIG. 86. A GAS FURNACE]

A gas furnace, see Fig. 86, is useful for tempering tools and other
operations where an intense heat is needed. A grinder, shown in Fig.
87, is used for grinding off rough parts of iron or brass castings and
for smoothing up rough surfaces. It is formed of a _mandrel_ which
turns freely in a pair of bearings set in a _headstock_. A pulley is
fixed to the middle of the mandrel and the latter is threaded on the
ends; an _emery_, or a _carborundum_ wheel is slipped over each end and
these are held in place by washers and nuts. A swivel _hand rest_ makes
it easy to hold the work against the wheel.

[Illustration: FIG. 87. A GRINDER AND POLISHER]

A plain lathe, see Fig. 88, is good for turning, drilling and facing
metal parts and for many other operations. It consists of a bed
supported on a frame which carries the driving pulleys; the latter in
turn is belted to a _cone pulley_ which is _keyed_ to the mandrel and
this runs in bearings in the _headstock_. The inner end of the mandrel
projects beyond the bearing and this is threaded so that a _chuck_,
that is a device with adjustable jaws for holding the work, can be
screwed on it.

Besides the headstock which carries the rotating mandrel, and which is
fixed on the left hand side of the bed, there is a _tailstock_ with an
adjustable mandrel which slides on the right hand end of the bed, and
between the headstock and the tailstock there is an adjustable hand
rest.

[Illustration: FIG. 88. A PLAIN LATHE FOR TURNING METAL WITH HAND TOOLS]

An engine lathe, as shown in Fig. 89, besides doing all an ordinary
lathe can do can be used for accurately turning up cylinders, disks,
etc., turning out cylinders and cutting screws of any size or pitch,
within certain limits, and it does all these things with rapidity and
precision.

A lathe of this kind has a _guide-screw_, a set of _change wheels_,
that is a number of interchangeable gears, and a _back-gear_, and by
means of these gears the guide-screw is revolved in any _ratio_ to
the speed of the gears which may be desired. For turning or cutting
a _slide-rest_ is used, that is an attachment sliding between the
headstock and the tailstock, for holding the tools.

[Illustration: FIG. 89. AN ENGINE LATHE FOR TURNING METALS WITH TOOLS
IN A SLIDE REST]

The slide-rest is made with two adjustable slides so that the tool can
be held in any position. The slide-rest can be moved freely by hand
or by means of the guide-screw which carries it along the bed at any
desired speed.

[Illustration: FIG. 90. PILLAR TYPE OF POWER DRILL]

A drill press makes drilling an easier and a more accurate operation
than when a lathe is used for this purpose. A pillar type of power
drill is shown in Fig. 90. It is so constructed that the drill can be
rotated at any one of a number of speeds and by means of a guide-rod
it is caused to advance into the metal _automatically_ at the proper
speed.

[Illustration: FIG. 91. A PLANER FOR SURFACING METAL WORK]

A planer, see Fig. 91, is a machine for turning up flat surfaces,
cutting slots and the like in metal parts. A planer is made up of a
_bed_, a _table_ in which the work is clamped and which slides back and
forth on the bed by means of a feed motion; a slide-rest, which carries
the cutting tool, is held above the bed by an upright frame and this
moves to and fro across the table.

[Illustration: FIG. 92. A SHAPER FOR SHAPING UP METAL WORK]

There are several kinds of shapers made and Fig. 92 shows one of them.
A shaper cannot only be used for planing, but for turning, boring and
slotting. In a shaper the work is held in a fixed position on the
table, which can be raised and lowered by a hoisting screw, and the
tool is made to move across the table by a quick-acting return motion.

There is also an _arbor_ on which the work is mounted where a circular
cut is to be made. The cutter head has a vertical adjusting screw with
a _worm feed_ and an index plate so that it can be set to any ratio. In
a shop where only small work is to be done a planer may be dispensed
with and a shaper used instead.

[Illustration: FIG. 93. A UNIVERSAL MILLING MACHINE FOR AUTOMATIC SCREW
CUTTING AND OTHER OPERATIONS]

A _universal milling machine_, see Fig. 93, is also a handy combination
tool in that it can be used for drilling, cotter drilling, boring,
profiling, key-seating, rack- and gear-cutting and other operations.

A buffing machine is made nearly like a grinder but leather, felt and
rag wheels are used on the spindle and when either pumice-stone, crocus
and rotten-stone is applied to them tool marks and scratches can be
buffed out and the work polished when it is ready to be _lacquered_ or
nickle plated.

[Illustration: FIG. 94. A JIG-SAW FOR SAWING SMALL WOODWORK]

If you are buying new machines get them fitted with individual electric
motors, as shown in Fig. 90, as this will save shafting, the time
and cost of putting it up, the cost of belting, besides the time the
machine is idle while the belt is broken and it is being laced again,
the loss of power in transmission, when the machine is idle, etc.,
etc.; boiled down, these machines equipped with individual motors are
the last word in modern shop practice and it is a good one for you to
follow.

[Illustration: FIG. 95. A BAND SAW FOR SAWING HEAVIER WOODWORK]

Whatever machines you order be sure to also order at the same time a
full supply of tools to use with them for otherwise you may find when
you have your machinery all set up and you think you are ready to start
that you are minus the cutting tools and should this happen you will be
in for another long delay.

Unless your product requires a lot of wood-work it will hardly pay you
to add a woodworking shop to your plant, though sometimes a _jig-saw_,
see Fig. 94, or a _band-saw_, as shown in Fig. 95, will often prove of
service.

It is the same way with a foundry, for unless you need a large number
of castings right along it is as a rule cheaper to farm the work out to
some founder in your own town.


~Buying the Stock.--~I do not mean the stock of your company--let your
friends and the public do that--but the raw materials, as the _stock_
is sometimes called, which you are to convert into the finished product.

Before you order either machinery or stock, try to _standardize_ your
product, that is to say whatever it is you intend to manufacture have
it in such shape that you are satisfied to market it without making
any further changes in it, at least for some time to come. It is the
after-changes, the constant changes that have kept many a manufacturer
poor, aye, forced him to the wall.

Having a standardized article, object or machine, you and your
associates should determine on the number to be built first and then
you can go over the model in detail and figure out just how much of
each kind of stock, such as brass rod, sheet hard rubber, screws,
washers, nuts, etc., you will need, allowing of course for waste and
breakage.

Now when you are ordering the tools and machines for your shop get
prices on and order your stock at the same time and see to it you do
not overlook any little thing and so have to wait for something you
forgot.

Screws, nuts, washers, bolts and some other small supplies can be
bought in wholesale lots cheaper than you could possibly make them in
your own shop and it is false economy to make anything with ordinary
machine tools that can be bought from some other manufacturer who does
the work with automatic machinery.


~Organizing a Shop Force.--~I am taking it for granted that if you
have enough ability to invent, design and make a working model of
an invention and get an _organization_ together to manufacture and
market it you will certainly have enough ability left to build up and
superintend the _body_ of your enterprise and that is your shop force.

Your first effort in this direction should be to hire a good foreman;
this, though, is not an easy thing to do for a foreman must be
something more than a thorough machinist who can use any tool or run
any machine. He must be able to get the best there is in them out of
the other men under him and see that each one is put on the job which
he is best adapted to do.

Some of the men will shine as bench hands, others will show an aptitude
in running machine tools and yet again others will be naturally clever
in assembling your device; he must be able to pick out these good
qualities and put the men where they will do the best work in the
shortest time.

By all means get a foreman, if you can, who has worked on something
like, or nearly like, your own product. He should be a man of shop
ideas with enough _initiative_ to put them into use. To get all these
things rolled into one human being for $25, $30 or $35 dollars a week
is asking a good deal but there are boss machinists in almost every
city who can fill the bill.

Your foreman can usually get all the mechanics you need but don’t make
the mistake of starting in and letting him hire the men. After he has
found a man and wants to take him on, then you talk to the prospective
employee, and you do the hiring. Hiring and _firing_ the men should
be your _prerogative_. This will make all of them respect you without
respecting their foreman the less and they will do more and better work
by knowing that you are the real boss of the works.


~The Stock Room.--~The tools that belong to the shop and the stock, or
raw materials, should be kept under lock and key in the stock-room and
a stock-clerk should be put in charge of and made responsible for them.

Have slips printed and whenever the foreman, or anybody else, including
yourself, wants a drill, or a piece of brass, or a machine screw,
insist that the stock-clerk get a slip signed for it. By this method
you will know exactly where your tools and stock went to; and when a
man returns a tool credit him with it.

You should also have a record kept of the time spent on each job by
the man who did the work and the easiest way to do this is to use
a time-stamp as shown in Fig. 96. If your shop is a small one your
stock-clerk can take care of the time-slips. By doing things in this
systematized way you will be able to keep pretty close tab on tools,
stock and labor and these are three _factors_ where a great deal of
waste usually occurs in small shops and factories.

[Illustration: FIG. 96. THOMPSON TIME STAMP]


~The Finished Product.--~Whatever you are manufacturing, the finished
product must be made as attractive as can be with the littlest
extra cost and this applies alike to a toaster for a gas-stove or a
threshing-machine. It’s the finish the buyer sees and he will gladly
pay for the paint and the gloss that covers up the defects, if the
thing looks nice.

Where a number of different materials enter into the make-up of
a device it is always well to give some thought not only to the
design,[5] but also to the color effect.

[Illustration: FIG. 97. A HIGH FREQUENCY MACHINE]

Figure 97 shows a _high frequency_ (violet ray) electric machine
designed by the author in which this idea is carried out. The stand is
of iron, nickle-plated; the base of the apparatus proper is of wood,
japanned black; the rim is of brass, nickle-plated; the plate-base,
on which the visible part of the apparatus is mounted, is made of
slate and japanned black; the metal parts of the interruptor are
nickle-plated, and the coil and insulating standards are of hard rubber
as is also the handle. The cover shade and the violet ray vacuum tube
are of glass, while red or green flexible silk cords are used to make
the connections, and finally the lamp socket is of a composition called
_electrose_.

Thus the color scheme is polished ebony, the wood base, the slate plate
base, hard rubber fittings and electrose socket all appearing precisely
alike; the blue-white nickle-plated parts alternate with the black, the
glass lends an added touch of beauty while the red, or green, cords
give it a dash of color that relieves and sets off the other parts.

Iron work can be _japanned_ black, _enameled_ any color, or
nickle-plated; brass can be lacquered or nickle-plated, and wood can
be enameled. After the device or machine is assembled it should be
rubbed up to remove all finger marks and to brighten it, then wrapped
in tissue paper and packed carefully in a box if it is small enough so
that this can be done, or it must be crated in such a way that it can
be transported without marring or breakage.


~Overhead Charges.--~In figuring on the cost of a completed device,
machine or product so that a selling price may be put on it which will
insure a handsome profit the cost of the stock, of the breakage of
tools, of the labor, or production, and of the power--gas, electricity,
water or coal--are all easy to keep track of.

But there are other costs that must be taken into account which,
while they do not stick out so plainly must also be reckoned with,
or your venture will be a money losing one. These are the _overhead_
charges, such as the _depreciation_ of your machinery, that is the
wear and tear of it; the rental of your factory, or the taxes if you
own the building; the insurance on the building and the machinery;
transportation costs such as teams and teamsters or automobile trucks
and drivers; telephone calls and the other little and big items of
expense--all of these must be carefully thought up and worked out for
the year and charged against the number of machines you are going to
make in that year.

To these fixed and variable charges must be added the salaries of
yourself and your associates and the office staff together with the
printing bills, advertising accounts and all the incidental expenses of
maintaining an executive office. Divide the total running expenses for
the year by the number of machines you have turned out in a year and
you will have the net cost of each article or machine you have produced.


~Where Your Profits Come In.--~Add 33⅓ per cent., 100 per cent., or 500
per cent. to the cost of production and let that be your selling price
to _consumers_, agents, jobbers or wholesalers, less the usual small
discount for cash. And the difference between the cost of production
and your selling price will be your _profits_ less certain losses on
accounts which even an agency can’t collect.




CHAPTER IX

PUTTING IT ON THE MARKET


Long before you get your shop into running condition and you are able
to fill orders, you and your associates will have talked over the best
way that should be adopted to put your article or machine on the market
so that it will bring in the largest returns in the shortest time.

Here again the method you will choose and use will depend on what you
have to sell and the backing you have to sell it with. Just as there
are only seven original jokes and all the others that you see and hear
are worked over and out of them so, too, there are only a few _basic
principles_ in the art of selling goods but these are modified into a
thousand and one schemes.


~How Best to Do It.--~How? Aye, that’s the question! But even as you
have had the genius to invent a new and useful time, labor and money
saving device--there will, among the men you have surrounded yourself
with, rise up one whose brains teems with schemes of ways and means to
dispose of the factory’s output at the greatest profit and you may have
a few stray ideas too as to how the thing can best be done.

In every business however small or large there should be frequent
_conferences_ of the partners, or of the heads of departments, and
to save time and to conserve energy it is better that these meetings
should be held at certain times each week, or oftener, when all of the
matters of the office and shop can be discussed freely and threshed
out. Indeed it is the common practice of every business concern where
there are a number of departments for the heads of them to get together
every day in conference to learn the viewpoints of the others.

[Illustration: FIG. 98. FROM THE MANUFACTURER TO THE CANVASSER, THENCE
TO THE CONSUMER]

By this method every one knows exactly where the business stands for
that day not only in his own department but in the other fellow’s as
well and he conducts his part of it accordingly. This welds the whole
business into an efficient unit instead of having it made up of a bunch
of straggling ends. If the business can’t be put on a paying basis
under such favorable conditions then you had better get a new partner,
hire a new manager or call in the old sheriff.


~Agents Wanted.--~Hundreds of small patented inventions as, for
instance broom hangers, pinless clothes lines and burglar alarm traps
are sold by the manufacturers of them directly to small agents all over
the country and who, in turn, sell them by making a house to house
canvass. See Fig. 98.

The amount of your sales under this plan will depend on the number of
agents you are able to secure and generally on the persuasive ability
of the rhinoceros skinned peripatetic to sell the good housewife
something which she truly doesn’t want. But should your invention be
one of exceeding merit--and of course it is--then the path of the
itinerant salesman is made glad and he sees a rose for every prick of
the thorn he gets.

Agents can be had by running small ads in the daily and Sunday papers
in the large cities under the classified head of _Agents Wanted_. There
are advertising agents who will _run_ an ad for you in 15 or 20 papers
throughout the United States, whose combined circulation runs up into
the millions of copies and all for a $10 bill. An ad of this kind can
also be run in such magazines as _Popular Mechanics_, _Popular Science_
and a dozen other like publications.


~The Mail Order Business.--~The two chief plans for working a mail
order business are (1) by selling direct from your shop to the consumer
and (2) by selling your product to agents whom you start in the mail
order business.

To work the first plan there are two ways by which you can get the
names of prospective buyers and these are (a) by running small ads in
the papers and magazines and (b) by buying a list of the names of firms
who make a business of classifying and selling them.

Regarding the first plan suppose you have invented a new _blood testing
apparatus_ in which case you couldn’t possibly hope to sell it to any
other class than doctors. Now you can buy a list of all of the doctors
in Boston, or of any other city, in Illinois or any other State, or of
all of them in the whole United States from _Boyd’s City Dispatch_, 19
Beekman Street; _Rapid Addressing Machine Company_, 374 Broadway, and
R. L. Polk and Co., Inc., 87 Third Avenue, all of New York City.

[Illustration: FIG. 99. FROM THE MANUFACTURER TO THE ORDER AGENT,
THENCE TO THE CONSUMER]

When you get this list you can then send out to each doctor a nicely
gotten up _folder_ or _booklet_ and a clearly worded letter, which you
can have _mimeographed_, that is duplicates made from the original
typewritten letter, and according to business rules and regulations
these ought to make a noise like a lot of orders.

Lists of men and women in every line of business, profession and trade;
including R. S. Dun and Company’s list which is guaranteed 99 per cent.
accurate, can be bought of the above concerns that are classified to
fit whatever article or device you intend to market. This is one way of
conducting a mail-order selling campaign.

The second plan as outlined above is to run small two to ten line
classified ads for agents offering to start them in the mail order
business. See Fig. 100.

Your proposition to each prospective agent who replies is something
like this: you will give him, provided he buys, for cash in advance,
of course, one dozen, one gross, or a dozen gross of the product you
manufacture, the exclusive territory of a city, a county, or several of
them, or of an entire State as you choose and according to the quantity
he buys.

Included in the price he pays, you furnish him with so many letter
heads and envelopes with his name printed thereon as _manufacturer’s
agent_; printed circulars or folders, a _series of follow-up letters_
and whatever else is needed to start him in the mail order business
except the list of names and the postage stamps he will use. It is up
to him to get these accessories.


~A Series of Follow-up Letters.--~By a series of follow-up letters is
meant that a number of different letters, say six, are written up in
such a way that each one makes a stronger appeal to the consumer than
the one he gets before.

Let’s say that your agent sends a circular describing the merits of
your _patent mailing box for eggs_ to an egg grower in the rural
district and with it a letter stating how glad he would be to receive
an order from him for a dozen mailing boxes, the price, etc.; if, now,
in ten days’ time no reply is forth-coming the agent mails him a second
letter, stating that he can’t understand why he hasn’t heard from him,
et cetera and so on. If this brings no response the agent mails a third
letter in another ten days saying that since he (the agent) has used
several stamps in writing to him suppose that he (the egg grower) sits
down and uses a stamp on him and so forth and _e pluribus unum_, as
Artemus Ward used to say.

And so the letters are mailed until the series of six have been sent
out at ten day intervals. The idea is that as the letters, each of
which is a little stronger than the one before it, reach the egg grower
with clocklike regularity the value of your patent mailing box for eggs
will sink deeper and with more telling effect into his _cranium_ and
that somewhere between the first and the last letter he will conclude
he had better order a dozen or more boxes.

If the sixth and last letter does not bring an order the agent may then
conclude that the chickens are dead, or that the roosters are sleeping,
or else that the egg-grower doesn’t want the mailing box and he knows
that he doesn’t want it. At any rate it is time for the agent to quit
wasting stamps on him.


~Selling Through Sales Agents.--~Turning now to big business one of the
most successful ways now in vogue to sell goods is the one adopted by
automobile manufacturers.

By this method the manufacturer sells his product to his own sales
agents and these in turn sell them to the consumer. Both the
manufacturer and his agents advertise, the former nationally, that is
he tries to reach all the people, and the latter locally, that is in
his own territory.

The result of their joint advertising is inquiries and these the
sales agent follows up by personal solicitation. Fig. 100 shows
diagrammatically how the scheme works out.


~Selling Direct from Factory to Consumer.--~A large number of
manufacturing concerns have built up profitable businesses by
advertising in various publications and dealing directly with the
consumer. See Fig. 101.

[Illustration: FIG. 100. FROM THE MANUFACTURER TO THE MANUFACTURER’S
AGENT, THENCE TO THE CONSUMER]

Many products, especially those in the nature of machines, can be sold
by this method where they could not be marketed in any other way.
Take as an example the larger sizes of hand power printing presses.
One firm has sold thousands of these machines through the persistent
use of small advertisements where only a few could have been disposed
of through dealers of any kind, for the reason that there is not a
sufficient demand for them in any one locality.

Any article, device or machine can be sold directly to the people
through the medium of cleverly displayed advertisements placed in the
right publications. When you get ready for an advertising campaign
write to any advertising agent--and he also advertises--telling
him what it is you have to sell and he will send you a list of the
periodicals which will reach the class of folks who will be interested
in your commodity and also quote you advertising rates. But of
advertising I shall have something more to say later on.

[Illustration: FIG. 101. SELLING DIRECT FROM THE FACTORY TO THE
CONSUMER]

Where you sell direct to the consumer you should also use, of course, a
series of attractive _pictorial_ cards, circulars, folders and booklets
which describe your offering in terms of glowing color and cold, hard
facts. Don’t try to deceive your customers for no business can be
conducted on misrepresentation and last, and besides it is just as easy
to enthuse with the truth as it is to equivocate, _not to use a harsher
and uglier word_.[6]

A series of follow-up letters should also be used and lists of the
people you want to reach are sometimes as useful, and occasionally more
so, in bringing results as advertising. In fact every art and device
known to the system of business should be freely used where there are
no middlemen.


~Selling Through the Trade.--~The older plan for a large manufacturer
to dispose of his goods is through the retail stores, but this is a
more costly and a harder way than by the direct method of reaching the
consumer.

The reason for this is that the manufacturer does not deal directly
with the retailer, but must do so through a lot of middlemen of whom
there are in some cases not less than three and often more.

[Illustration: FIG. 102. SELLING THROUGH THE TRADE]

Figure 102 shows how many different concerns stand between the
manufacturer and those who buy his goods; the manufacturer turns his
product over to the _commission man_ who unloads it on the _jobber_ or
_wholesaler_, who sends _drummers_ on the road, who make the _retailer_
buy it, who hands it out over the counter to his _customers_, who are
merely acquaintances of his.

All of the middlemen make big profits while the manufacturer and
the retailer have to be satisfied with a very small margin and the
consumer knows that he is paying several prices too many for the
article he buys.

The advantage, though, of handling your product through middlemen lies
in the fact that you can very often get a commission man, or a jobber,
to contract for the entire output of your factory, and sometimes a
certainty of this kind with small fixed profits is better than taking a
chance of putting a large sum into advertising with the uncertainty of
large profits or of no profits at all.


~Getting Publicity.--~Going back once more to the time when you have
completed your model and your patent has just been granted, it is often
a good idea to give some _publicity_ to your invention.

By publicity I mean to get some _write-ups_ in the papers and some
articles in the magazines and if you go about it the right way it will
not cost you anything for space and sometimes the editors will even pay
you for your contributions.

When you have reached the stage where you want some publicity write up
a clear description of say 500, 1000 or 2000 words, depending on the
importance and intricacy of your invention, and have a typewritten copy
made of it; next have some good 5 by 7, or better, 8 by 10 photographs
made of your model from different viewpoints. Small kodak pictures are
of no value in obtaining free publicity for clean-cut, large pictures,
count for as much or more with the average editor than either subject
matter or written copy.

Now the kind of publications in which you will want your article to
appear will hinge on the class of readers who will be interested in
it. But let’s suppose that it is a new machine, or a new electrical
apparatus of some sort or other. If it is a machine send your
typewritten article to the editor of the _Scientific American_,
Woolworth Building, New York; if your photos and article appeal to the
editor as being new and novel he will most certainly print them in his
paper.

In an article of this kind it is not good policy to crack up yourself
or put in your street number, as this savors too much of trying to get
a page or so of advertising in the body of the paper free of charge;
your name and the city where you live are enough to include in the
article, but in a letter accompanying the latter you can send your
detailed address. And you can send in another article and photos to the
_Engineering Magazine_, 140 Nassau Street, New York; _Machinery_, 140
Lafayette Street, New York, and other publications of a like character.

Should your invention be electrical, or have a single electric element
connected with it, send your article to the _Electrical World_, 239
West 39th Street and to the _Electrical Review_, 13 Park Row, both of
New York, and the editors of either of these publications will most
surely and gladly accommodate you with space for your contribution.

The purpose of having articles appear in these _technical_ papers is
not so much to sell your product as it is to give you an _authentic_
article in a standard publication which you can refer to and reprint
from for distribution to those whom you may want to interest either as
partners or shareholders. Reprints are also useful for _circularizing_
agents or consumers after you have your factory in shape to take care
of the orders.

Should your invention have to do with mining send in your article and
photographs to the mining papers, if it is in the notion line mail it
to the dry-goods papers and so on for no matter what you have invented
you will find one or more trade papers in that particular field who
will give you the desired publicity.

After some good technical, or trade paper has published an account of
your invention the daily and weekly papers in your home-town are apt to
be impressed with the importance of what you have done and one or all
of them will give you quite a write-up.


~Advertising.--~While publicity and advertising are one and the same
thing in that both of them make known to the great body of buyers the
merits of your invention I have _arbitrarily_ divided them into two
classes calling (1) everything that is printed as straight reading
matter in a paper and free of charge _publicity_ and (2) all that is
displayed to attract the attention of the reader and paid for at space
rates as _advertising_.

You can begin an advertising campaign with a very small outlay of
capital by running a ½ inch, one column wide ad in ten or a dozen
papers or magazines as a starter. To have your ad _displayed_ as
you want it, that is the style of type and the illustration that
goes with it, get your local printer to set it up and have as many
_electrotypes_ made from it as there are papers you intend to buy space
in. Then all you have to do is to mail one of these electrotypes to the
publisher and it appears in his paper exactly like the type from which
it was made and it can be used over and over again.

This _stereotyped_ kind of an ad which meets the reader’s eye in nearly
every publication he picks up will finally get through the pores of the
calcium salts which form his skull and impress the sensitive area of
his brain, or, to use the language Evelyn doesn’t like, it _gets on his
nerves_ and he will read it. Every time he sees it after that he will
remember its message and then when the _psychological moment_ arrives
and he wants your product he will send to you either for a catalogue
and price-list or for the thing itself.

Larger ads should have the reading matter and the cut changed
frequently, but it is always well to use some design, or a name (see
Chapter XII), which stands out boldly in relief so that it will flag
the attention of the reader immediately he turns to the page where it
is displayed. The rest of the ad must then be catchy enough to induce
him, or her, who sees it to read it, and last of all it should contain
some gem or germ of knowledge which he, or she, will carry away and
think over and always to the end for which your ad was written and
designed--and that is to buy your product.

Writing alluring ads requires inventive ability but of an order very
different from that which produces a new machine. Hence there are
inventors who make a specialty of writing ads but they are content to
call themselves originators.

Should you have a product that you intend to give wide publicity to,
whether it is your intention to sell to the consumer direct or to
sell to him through the retail trade, it is a good plan to engage the
services of an advertising firm to conduct the campaign for you.

If you are going to spend $1,000 or $100,000 on making your product
known among men and women and popularizing it so that everybody will
buy it, or wants to buy it, it is well to have an advertising agent
or firm get up the ads, place them in the papers where they will do
the most good--in a word engineer the whole thing for you while you
are superintending your factory and your partner is taking care of the
orders--then all you have got to do is to count the _shekels_ that roll
in or out as the case may be.




CHAPTER X

THINGS FOR YOU TO INVENT


All through this book I have done my best to nickelplate you in the
bath of my own experience and I believe I have made everything clear
unless it is just how to get the big idea.

And even if I could give you a hard and fast rule for thinking up new
and novel things I have grave fears I would be tempted to keep that bit
of information to myself and start up an _idea factory_ in opposition
to Edison.

But while it is not yet possible to lay down a law for the creation of
an original idea it may prove of some value to tell you something about
what is needed both small and large and this in itself may serve to
stimulate your thought centers to activity.

As you look about and see all the different materials, apparatus and
machines that have been invented to make work easier, to save time
or goods and to increase safety and comfort you may on first thought
conclude that everything the human race really needs has been invented
and this is in a large measure true.

But the secret of present day inventing was let out of the bag
by Edison when he said that “hardly any piece of machinery now
manufactured is more than 10 per cent. perfect.” Certainly the
electric lights we now have are good enough as far as the light goes
but light costs us ten times as much as it ought to cost for the reason
that 90 per cent. of the energy there is in a ton of coal is wasted and
only 10 per cent. of it is transformed into actual light.

Oliver Lodge, England’s greatest electrician, once said that if we
knew how the glow worm makes his light then a boy could turn a machine
that would develop enough electricity to light a factory. The problem
for you to tackle then is not to make a _better_ light but to make a
_cheaper_ light.

And what Edison has said about machines and Lodge has said about light,
I say is just as true of everything else we have for lessening labor,
for saving time and materials, making for safety and adding to comfort.
Everything that has been invented up to the present time, with very few
exceptions, such as the electric motor which is 98 per cent. efficient,
can be made nearly 90 per cent. better.

This gives you your cue for inventing, that is to conceive and
_improve_ upon what has been done rather than to sap your life’s blood
and waste time, which is just as precious if you only know it, in
trying to invent something entirely new and original under the shining
sun.

Nor do you need to undertake to improve upon the big things--unless,
of course, you get a great idea and you feel that the world can’t
get along without it and that you would lose a fortune unless you
straightaway developed it. Otherwise just keep your eagle eye on the
lookout and your inventive brain cells on the alert and it will not be
long before you will see something where there is room for improvement.


~Some Little Things Needed.--~_For the Person._--There isn’t a thing
you wear, or carry in your pockets, or use in making your toilet but
which can be improved upon.

Your suspenders, your corset, cuff buttons, dress-shields, necktie
clasp, hose supports, garters, hat pins, collar buttons, eye glasses
and eye-glass guards, hair curlers or straighteners according to the
dictates of fashion, jewelry guards, fasteners for clothing, clothes
hangers and clothes presses ought all to be done over and re-invented.

[Illustration: FIG. 103A. OLD STYLE TOOTH BRUSH]

[Illustration: FIG. 103B. AN IMPROVED TOOTH BRUSH]

A better way to clean teeth, see Fig. 103, to shampoo the head, to
manicure nails, to wash backs and to shine shoes should all have
attention. Improvements in false teeth and in making the deaf hear are
in order; but it is just as well to keep away from inventions to make
the hair grow and to remove freckles.

_For the House._--You can help to save mother’s time and conserve her
strength by inventing any of the following devices and besides you’ll
make enough money so that she won’t have to use them and that will be
still better.

[Illustration: FIG. 104A. THE OLD WAY--THE CARPET SWEEPER]

[Illustration: FIG. 104B. THE NEW WAY--THE VACUUM CLEANER]

Odorless cooking utensils, candy making apparatus, visible ovens, dish
washer, ironing machine, soap saver, milk jar seal, fish scaler, fire
extinguisher, water cooler, water purifier, cheap ice machine, ice
crusher, window cleaner, silver cleaning apparatus, vacuum cleaner, see
Fig. 104, knife sharpener, fountain scrub brush and all kinds of handy
tools are needed.

A self-serving dining room table that will let the folks eat instead of
keeping every one busy waiting on everybody else between bites should
and undoubtedly would find a large sale.

_For the Farm._--Improved farm machinery has made the farmers and the
inventors rich and important but the little things around the farm have
been sadly neglected and if some one doesn’t come to its rescue pretty
soon it will go to rack and ruin.

[Illustration: FIG. 105. A LABOR SAVING PAINTING MACHINE]

A substitute for leather, mail conveyer to carry mail from the road
to the house, a painting machine, see Fig. 105, cheap fence posts,
fattening apparatus for chickens, insect exterminators, portable
fences, nests and coops for chickens, traps for preying birds,
parcels post cartons for butter and eggs, incubators, brooders, cream
separators, milking machines, and everything else used on the farm can
be made more efficient than the present apparatus and machines which
are now used.

_For the Office._--There was once a time when a shingle swinging in
the breeze, a desk, a chair and a spittoon constituted an office, but
those halcyon days of Lincoln and Douglas, Calhoun and Webster are gone
forever.

[Illustration: FIG. 106. A QUICK FIGURING AND BOOKKEEPING MACHINE]

What is needed now are not brains so much as an improved file case,
time stamp, check protector, gumless mucilage bottle, inkwell that
cleans the pen, safety envelope that can’t be opened without detection,
mailing boxes and tubes, envelope inserting and folding machine,
duplicating processes for typewritten copy, envelope opener, improved
dictaphones, that is phonographs for dictating to stenographers, and
figuring and bookkeeping machines; see Fig. 106.

_For Fun._--There is a great demand for toys and amusement devices and
novelties of all kinds.

Little 5 and 10 cent jokes, like the snake jar, shadow dancer, shooting
pack of cards, rubber dagger, see Fig. 107, and the musical seat,
puzzles like the beast, the star and crescent, Billy Possum, devil
lock and Chinese conjuring rings and games, tricks, magical advertising
novelties and the like are profitable in a small and sometimes in a big
way.

[Illustration: FIG. 107. A RUBBER DAGGER, AN AMUSING TOY]

Merry-go-round, shoot-the-chutes, bump-the-bumps, see Fig. 108, dips
and slides are some of the larger amusement inventions that have been
making money at summer and seaside resorts. What you must do is to
provide other new and novel means for the fun loving people to do
ridiculous stunts and pay you for the privilege.

Now while all of the above devices have been invented and patented
the point is that every one of them has a _bug_, that is a flaw in it
somewhere; by which I mean that in each and every case, except the toys
and amusements, the device is too hard to work, costs too much, takes
too much time, is too troublesome, is too poorly made or is not as
comfortable as the old-fashioned thing.

It is your business as an inventor to improve it so that your device
will do the work or serve the purpose better than it has ever been
done before. In order to improve a compound, device or machine to this
extent you will have to introduce some new principle, or element into
it and it is this added cause, or part in _combination_ with the other
and well-known arrangements that gives it a new and novel twist and for
which you pray that letters patent may be granted.

[Illustration: FIG. 108. BUMPING-THE-BUMPS]


~Some Big Inventions Needed.--~_Safety First._--That there were 38,000
deaths, 500,000 seriously injured and 2,000,000 slightly injured
persons caused by all manner of accidents in 1915, shows how badly
improvements are needed for all kinds of machinery, in the operation
of mines, railroads and steamships and in the manufacture of certain
chemical products such as phosphorus matches and dynamite. There
is money and lots of it in inventions that have for their object
the safeguarding of human health, limb and life. Fig. 109 shows a
life-saving gun.

[Illustration: FIG. 109. A NOVEL LIFE-SAVING GUN]

_Automobiles._--The automobile is the speed machine of to-day.
Pneumatic tires, transmission gears and differentials, must go for
they are bothersome, complicated and costly. An engine without poppet
valves, carburetor, high tension ignition system and water cooling
system with its expensive radiator would be most welcome. A magnetic
clutch that does away with the transmission gears is shown in Fig. 110.

[Illustration: FIG. 110. THE OWEN MAGNETIC CLUTCH]

A cheap substitute for gasoline is heartily to be hoped for and
inventors are searching for it now. The engine of the future will be
driven by some high explosive mixture each ingredient of which will be
perfectly harmless in itself but when the fractional part of a drop of
each chemical is mixed with the other in the cylinder of the engine
they will combine and explode violently.

_Aviation._--The aeroplane is the speed machine of to-morrow. The great
requirement of the present time in the flying machine is _inherent
stability_, which means that it is so designed that it will not
overturn, or if overturned it will right itself of its own accord.
Fig. 111 shows a gyro-stabilizer for this purpose.

[Illustration: FIG. 111. A GYRO-STABILIZER FOR MAKING AN AEROPLANE KEEP
ITS BALANCE]

After stability the next most desirable improvement needed in an
aeroplane is one that will make it rise from the ground at a far larger
angle from the horizontal, that is fly more nearly straight up than
those that are built at the present time. A better engine, an easier
way of starting and a surer way of alighting, are next in order.

_Chemistry._--There are unlimited possibilities in chemistry for making
big inventions. A method to produce cheap liquid air, see Fig. 112,
would revolutionize many industries. Radium which is worth $1,000,000 a
pound, or thereabouts, is plentiful in nature and requires some simpler
method only for its cheap extraction. But both of the above are very
hard things to do.

[Illustration: FIG. 112. A LIQUID AIR MACHINE]

[Illustration: FIG. 113A. THE CHEAPEST FORM OF LIGHT]

_Artificial_ milk, tea, coffee and eggs, the extraction of _caffeine_
from coffee, _thein_ from tea and _nicotine_ from tobacco--which are
the harmful chemicals in these products, a cheap method of producing
artificial ice, or refrigeration without ice, a substance to _denature_
alcohol are only a few of the things to be invented in chemistry.

_Synthetic chemistry_, that is the artificial production of real
rubber, camphor, diamonds, rubies and other precious stones, dye-stuffs
and other products heretofore supplied only by nature, also offers a
large and fascinating field for the inventive chemist.

[Illustration: FIG. 113B. A TUBE SYSTEM OF ELECTRIC LIGHTS]

_Electricity._--There are hundreds, if not thousands of electrical
inventors who are busier than a swarm of bees in a field of clover, but
there is enough left for all of them and as many more to do if they
worked in eight hour shifts until the dawn of the millennium.

An apparatus for dispelling fogs by electricity, television, or
transmitting sight by electricity, cheap electric lights, see Fig. 113,
a simple telautograph, or writing telegraph, a means for directing
wireless telegraph and telephone messages, automatic block signals
which operate in the engine driver’s cab and are positive in action,
transmitting pictures by wireless and a cheap and powerful generator
of sustained electric oscillations by a battery or other low voltage
current, all these needs show that there is still plenty of room for
improvement.

_Electro-Chemistry._--In this field of endeavor the things that are
needed would fill a large book and many things that will come have not
even been dreamed of yet.

A few that I can think of is a self-charging primary battery, a
light weight storage battery, a way to produce electricity direct
from coal, a scheme to prevent _electrolysis_ in underground pipes,
the _electrification_ of farming lands to make forty bushels of rye
grow where only one was sown, see Fig. 114, to store up electrical
energy from the sun and the production of entirely new and unheard of
substances in the electric furnace.

[Illustration: FIG. 114. FARMING BY WIRELESS. THE HIGH TENSION ELECTRIC
GENERATOR]

_Building._--In the building line heating, ventilation and drainage
are all open to great improvement. Glass that can be bent to shape
and which cannot be so easily broken is much needed while fireproof
materials and fire protection leave much to the inventor to perfect.
Even improvements are needed for wrecking buildings as will be seen in
Fig. 115.

[Illustration: FIG. 115. CUTTING STEEL GIRDERS WITH THE OXY-ACETYLENE
PROCESS]

_Mining and Metallurgy._--Safety appliances are of the first importance
in mine inventions, see Fig. 116, and after these, machines for labor
saving should receive attention. If you understand mining, be it for
coal, metals or gems, you will see that there is yet much to be done to
make the operations safer, more saving and less laborious.

[Illustration: FIG. 116. AN APPARATUS FOR THE PREVENTION OF MINE
DISASTERS. It records the presence of gas]

After the ore is mined, the metal must be separated from it and this
is largely a matter of chemistry and mechanical devices. _Saving_ is
the watchword for the inventor who would improve the present methods
and processes. If you can show how a saving of metal can be effected or
how the same amount can be extracted more cheaply you are the boy the
owners are looking for and you can name your own price, nearly.

An alloy for armor which will deflect projectiles, steel rolls which
will roll and straighten sheets and rails with one handling, a process
for extracting metals from low grade ores, a process for making small
brass, iron or steel castings in much the same manner that a linotype
machine casts a type slug, are all improvements for you to think about
even if you don’t try to invent them.

_Printing._--The noble art of printing has been brought to such a high
degree of perfection it would seem to leave little to be invented. But
like all the arts and sciences there is yet much to be done.

[Illustration: FIG. 117. A STEEL PLATE ENGRAVING MACHINE One boy does
the work of four men]

A few gentle hints in this direction is the need of a three color
printing press, machines for engraving steel plates, see Fig. 117, and
presses for printing from them, power copper plate presses, printing
without ink by means of electricity and bookbinding, electrotyping and
typefoundry processes and machinery; all these, and many more need
looking into.

_Moving Pictures._--Three great improvements must be made in
the moving picture industry before it will take on anything like
perfection, and these are (1) a film that is not easily broken, is
as transparent as glass and is fire proof; (2) pictures that are
photographed on the film and projected on the screen in their natural
colors, and (3) moving pictures that are made and projected on the
principle of the _stereoscope_ so that the picture will stand out true
to life in color, time and space. The last word in moving picture
machines at this writing is shown in Fig. 118.

[Illustration: FIG. 118. AN ATTEMPT TO IMPROVE THE MOVIES This machine
uses glass slides instead of films]

All of the above improvements have been made but they are each of
them very crude and they must be re-improved to a very great extent
before they can be successfully shown in theaters. I do not believe any
attempt has yet been made to combine the three features in a single
machine.

_Other Fields of Endeavor._--There are many other fields that are
just as full of promise for the inventor as those I have cited and
among them may be named railways and steamships, boilers and engines,
bridge building, munitions of war, textile and boot and shoe machinery,
medical and dental apparatus and instruments, devices for the postal
service, musical instruments, vending machines and the utilization of
by-products. Verily there is everything under the heavens for you to
improve if you will but find out a new means, devise a scheme, discover
by art, contrive by ingenuity or, in a nutshell, originate an idea,
work it out, patent it and beat the other fellow to it.

[Illustration: FIG. 119. THE WIRELESS TRANSMISSION OF POWER

Tesla’s tower at Wardencliffe, Long Island]


~What Not to Invent.--~If you have but little time, small means and are
without tools it were better not to get too big an idea for your first
invention. Try out your genius on some simple thing, that is if you
can.

Of course should some great improvement strike you it would be folly to
drop it simply because you happened to be handicapped in two or three
several little ways. When in such a predicament you must rise above the
level of mediocrity and circumstance and invent a plan to raise the
necessary funds to go ahead with your experimental work.

[Illustration: FIG. 120A. A PERPETUAL MOTION MACHINE. (IMPRACTICAL OF
COURSE)]

But whether you have or have not the quick capital of your own to draw
on there are some things you should not try to invent--that is if you
are an inventor for the financial profits you expect to accrue from
your work. If you are doing it purely as a scientist that is a horse of
quite another color and some scientific society may present you with a
medal in a plush lined case and its _Transactions_ will laud you for
your unselfish work.

Such schemes as extracting gold from the salt water of the sea, milking
electricity directly from the ether, blowing up ships at a distance by
means of invisible waves, making a _phonotypograph_ which will, when
spoken into, print what you have said on a sheet of paper, printing
without type by means of the X-rays, sending wireless messages to Mars
and the wireless transmission of power, see Fig. 119, are all good
things to let alone.

[Illustration: FIG. 120B. PERPETUAL MOTION AS SEEN BY A PATENT-ATTORNEY
(HYPER-THEORETICAL)]

Not because these innovations are impossible to invent--they will all
come into general use some day--but because it is not given to any
inventor to work a single one of them out alone and so I say don’t try
to unless you are a real Simon pure scientist.

And as a last piece of advice don’t try to invent that monstrous
impossibility--_perpetual motion_.




CHAPTER XI

WHAT SOME INVENTIONS HAVE PAID


One of the most alluring and sky-blue delights, next to working out
a big idea of your own, is to read about the fortunes that other
inventors have piled up by the simple use of their _grey matter_.

The stories of what they did and how they did it are far redder blooded
and more gripping than any old sleuth yarn ever put between paper
covers; but different from this kind of yellow fiction they are all
true, their heroes are all real and each one had a great idea burning
in his brain, like St. Elmo’s fire, and each had the business ability
to transmute it into solid gold, twenty-four carats fine.

And it is not time wasted in harking back to what other inventors have
done if you will but heed the lesson that they teach for their works
stand out like guide-posts by day and signal-lights by night which
point the way for you to go and do the same thing if you will only quit
dreaming, get busy with your experiments and be careful not to run into
any open switches.


~A Tour of the Inventive World.--~Nor need an invention be a large
one to make money though of course the great inventions--those that
have given the world all the civilization it has had or is likely to
have for some centuries to come--have, as a rule, been the greatest
producers of wealth for those who worked them out.

So now suppose we make a personally conducted tour around the world of
inventions and take a look at a few of the wonders which prove that
_thoughts are things_ and that _things are money_, that is when you
know how to convert one into the other. And the route we will take will
show us some small inventions as we go and we will see a few of the big
inventions on our return to home and laboratory.


~Little Inventions.--~To begin with let us lead off with the smallest
and least important inventions, though they also serve a purpose, and
these are to be found in toys, games and other things for pleasure.

First is the return ball, which consisted of a piece of rubber strand
fastened to a wooden ball; this simple invention, so ’tis said, paid
its inventor $50,000 a year in royalties for a long time, and so he
waxed fat and grew rich.

Such toys as the dancing dolls, the wheel of life and the chameleon
top brought their respective inventors even larger sums, while the
roller skate which Plimpton improved and made popular by his invention
of _cramping_ the wheels netted him $1,000,000 in royalties and so you
need not feel sorry for him.


~Simple Inventions.--~The next class of inventions I shall call your
attention to is just as simple but they are different from toys in that
they are useful.

Among them may be named our friend of infant days, the safety pin, the
rubber tip for lead pencils, the cork nose shield for eyeglasses, the
grooved steel rib for umbrellas, the stylographic pen, the glass lemon
squeezer, paper clips, hook fasteners for shoes and the shipping tag
reinforced around the hole which Dennison invented and still sells by
the carload.

All of these little things and ten thousand others which you would
hardly think were worth inventing have built up fortunes for those who
thought of them and, more to their credit, were able to see that a
future awaited them.


~Real Inventions.--~In passing we come to some small but none-the-less
real inventions such as the spring roller window shade, automatic ink
stand in which the ink is always at the same level, barbed wire fences,
Mrs. Potts’ sad iron--the one with the attachable and detachable
handle, the paragon umbrella frame, etc.

To the right you will see some inventions of a more complex kind
such as the check protector, mimeograph, time stamp, combination
lock, fountain pen, computing scale, compressed air rock drill, cash
register, the comptometer and a thousand other devices we see in use or
use ourselves every day. Many of them are small but each and every one
produced anywhere from $10,000 to $1,000,000 for its inventor.


~Great Inventions.--~_The Steam Engine, Locomotive, and
Steamboat._--How the steam engine was invented by Watt, how the
locomotive was invented by Stephenson and how the steamboat was
invented by Fulton are pretty well known.

Just how much these great pioneer inventors received in actual cash for
their efforts I cannot say offhand but it was not large when compared
with the fortunes inventors have since made. But their names are writ
large in the hall of fame, not the one at the New York University which
doesn’t count, but in the hall of fame of progress and civilization
which is the only one that really matters.

_The Telegraph._--The _telegraph_ was invented by Samuel F. B. Morse
in 1832 but it was not until 1844 that he had a line working from
Washington to Baltimore. After long years of _litigation_ his patent
rights were upheld by the courts and much wealth and more fame accrued
to him.

_The Perfecting Press._--The first _web printing press_, that is a
press using a web, or continuous strip of paper, was invented by
Bullock in 1845 and this the Hoe Brothers improved upon until the _web
perfecting press_ was evolved by them in 1846 and which revolutionized
the printing of newspapers. The Hoe factory is the largest maker of
printing presses in the world to-day.

_The Sewing Machine._--After many experiments by others the _sewing
machine_ was invented by Elias Howe and patented by him in 1846. Like
every other inventor who has a really great thing his patents were
attacked in the court and for eight years he lived in poverty. When the
courts finally found in his favor he made millions out of the royalties
on his labor saving invention.

_The Ice Machine._--The first machine for making ice was invented by
A. C. Twining in which _ethyl ether_ was used for the compressed gas
and for which a patent was granted in 1850. In 1867 an _ice machine_
was made by Ferdinand Carré which used _liquid ammonia_ for the
compressed gas and from that date on the artificial production of
ice on a commercial scale really began. Whether these two inventors
made fortunes out of their brain children I cannot say, but this I
know, that tens of millions have flowed into the coffers of those who
commercialized their work.

_The Steel Process._--The process of converting iron into steel cheaply
and in quantities was invented by Henry Bessemer who patented it in
1855. It was the _Bessemer process_ which made it possible to use
steel for rails and structural purposes generally. The inventor grew
rich beyond the dreams of the romancer and the steel industry has made
multimillionaires of all its captains.

_The Gas Engine._--Many inventions for using gas as the motive power
for engines were made before 1861 but it was not until that year
that N. A. Otto built a working model of a _gas engine_ in which the
explosive gases were mixed, compressed, and ignited in one cylinder
when the waste gases were exhausted from it. The Otto gas engine became
a commercial success in 1878 and netted the inventor many millions.

_The Dynamo and Motor._--The principle on which the _dynamo electric
machine_ works was discovered by Faraday in 1831. In 1866 both Wilde
and Siemens built _dynamos_, but it was Gramme who made the dynamo a
commercial machine by inventing the _ring armature_, which he did in
1870. Then some genius, or bonehead, no one seems to know which, found
that when a current was passed through a dynamo it became a _motor_.
From 1880 inventions for electric light, heat and power advanced by
leaps and bounds and everybody that invented anything at all worth
while in the electrical line got rich quick.

_The Air Brake._--The _air brake_ to stop and control the speed of
trains was invented by Westinghouse in 1869. He had hard work getting
any railroad to give it a trial but once that this was done it very
quickly came into general use. Next to the _safety valve_ it was the
first important safety device applied to railroads. It has in the past
and is still piling up millions for its inventor.

[Illustration: FIG. 121. THE FIRST TELEPHONE]

_The Telephone._--The first use of the word _telephone_ was made by
Charles Wheatstone in 1834, who applied it to a musical instrument
otherwise known as the _magic lyre_. In 1854 Charles Bourseul suggested
a way to make a speaking telephone, and in 1860 Johanne Phillip Reis
constructed a telephone apparatus along the line of Bourseul’s idea;
while this instrument reproduced musical tones it would not reproduce
the human voice.

[Illustration: FIG. 122. THE ORIGINAL TYPEWRITING MACHINE PATENTED BY
W. A. BURT, JULY 23, 1829]

Alexander Graham Bell began working on the problem in 1874 and invented
the first electric speaking telephone which he patented, showed in
operation at the _Centennial Exhibition_ at Philadelphia in 1876 and
shortly after a company was formed to float it. Edison made a big
improvement in the telephone in 1878 when he invented the _carbon
transmitter_. Other rivals appeared in the field and after long years
of costly law suits the rights of Bell were sustained by the courts and
the Bell Telephone Company has had a practical monopoly of the business
in this country ever since. The invention made Bell and its owners
enormously wealthy.

_The Typewriter._--This useful machine was invented by Charles Thurber
in 1843, but it was not until about 1875 that a practical machine
was put on the market. Millions of dollars have been made out of the
typewriter industry, subsequent inventors coming in for their big
shares, but it is doubtful if the original inventor received anything
more than honorable mention in the _encyclopædias_ and a monument in
some cemetery for the great benefit he conferred on mankind.

[Illustration: FIG. 123. THE FIRST PHONOGRAPH]

_The Phonograph._--This wonderful instrument for recording and
reproducing speech and other sounds was invented by Edison in 1877 and
improved by him in 1888. In 1887 Emile Berliner invented and patented
the _graphophone_ in which the vibrations are recorded on a disk
instead of on a cylinder as it is in the Edison phonograph.

The phonograph was placed on the market in 1888 and the manufacture
of graphophones began in 1897 when both the machines and the records
became popular and rapidly grew into a great industry. The phonograph
is only one of Edison’s 700 inventions and from some or all of them he
has amassed a fortune of $10,000,000, and Berliner, who is also an
inventor of renown, is very wealthy.

_The Storage Battery._--Like many other great inventions the _storage
battery_ has made millions, but from the time it was invented by Gaston
Planté in 1860 until it became a commercial product in 1880 was too
long a stretch for the originator to have received his just reward.
But those who followed with their little and big improvements made
small and large fortunes out of them when the Electric Storage Battery
Company of Philadelphia was organized to take over all the smaller
concerns.

_The Snap-Shot Camera._--The snap-shot camera, or _kodak_, is not
an invention of magnitude but Eastman who invented it about 1880
has through his business ability made it a money-maker second only
to inventions of great utility. So rich is his company that it paid
$300,000 for the simple invention of enabling a kodak user to write a
record on each film when it was exposed.

_The Steam Turbine._--The steam turbine dates back to the time of Hero,
that is 120 years B. C., and the place of its birth was Alexandria,
Egypt. It consisted of a copper ball pivoted on trunnions. Projecting
from opposite sides of its equator were two bent pipes and when the
ball was partly filled with water and heated the steam would spout
out of the bent pipes and on striking the air it reacted on the ball
and this caused it to revolve at a high-speed. For this reason Hero’s
engine was called a _reaction_ turbine.

In 1705 Branca, an Italian, invented a steam turbine in which a jet
of steam was forced through a nozzle and impinged on the vanes of a
paddle-wheel, the impact of the steam causing it to revolve. Hence this
kind of a turbine is called an _impact_ turbine.

The first steam turbine to be built and operated as a competitor of the
_reciprocating_ engine was made by De Laval in 1883. It was a reaction
turbine and it revolved at a tremendously high speed. Parsons of
England brought out in 1884 the first multiple expansion turbine which
combined the reaction and the impulse types. It made 18,000 revolutions
per minute and was directly connected to an electric lighting dynamo.
In a little over thirty years the steam turbine reached a degree of
perfection and economy not attained in the two hundred odd years of
development of the reciprocating engine and it is now used for driving
the largest steamships.

_The Automobile._--The so-called daddy of the _automobile_ is George
B. Selden; he built his _first self-moving wagon_ in 1878 and applied
for a patent on it. He did not let this patent issue, however, but kept
it alive in the Patent Office until 1895 when in that year automobiles
began to be made and used and he then had the patent granted to him.

His next step was to sell licenses to the various gasoline engine
automobile manufacturers who paid him a royalty on each machine sold
and in this very easy and genteel manner he accumulated much money.
But there were some manufacturers who refused to recognize his patent
rights and hence refused to pay him royalty. Henry Ford of Detroit was
the leader of these rebellious souls and a bitter patent suit resulted
in which the courts first decided for Selden and then against him and
this ended his monopoly.

Ford organized the Ford Motor Company and at this writing it is the
largest manufacturer of automobiles in the world. It employs 16,000 men
and turns out 1000 automobiles a day. Mr. Ford has so much money he
doesn’t know what to do with it, but his great wealth is based upon his
business ability and not upon any patents he may have.

[Illustration: FIG. 124. FIRST INCANDESCENT LIGHT]

_The Incandescent Light._--The first electric _incandescent_ lamp
that was made used a _platinum_ wire for the filament. J. W. Starr
substituted a _carbon filament_ for the platinum wire, but the first
successful incandescent lamp was produced by Edison in 1879 after he
had made over 2000 experiments in order to find a suitable fiber for
the filament. In order to be able to use the incandescent lamps, Edison
designed a new system of distributing the current through several
circuits and between any number of lamps.

The lamps of to-day have filaments of _tungsten_ and these are sealed
in bulbs filled with nitrogen and which together greatly increases the
candle-power and at the same time uses less current. In 1882 the Pearl
Street Edison station in New York was put into service and was the
first of the great central stations. The Commonwealth Edison Company of
Chicago is the largest electric lighting system in the world. There are
four stations and together they have an output of 320,000 kilowatts, or
430,000 horsepower.

_The Electric Railway._--The first attempt to build a railway operated
by electricity was made by Thomas Davenport, a Vermont blacksmith in
1835. Next, C. T. Page made a sixteen horsepower electric locomotive in
1850 and when it was tried out on the Baltimore and Ohio Railroad it
ran at a speed of nineteen miles an hour. Batteries were used in both
cases to supply the current.

_The Trolley Car._--The first practical overhead electric line was
shown in Chicago in 1883 by C. J. Van Depoele and about the same time
Leo Daft built a third-rail line from Saratoga Springs, N. Y., to
Mount McGregor, while a conduit line was built by Bently and Knight in
Cleveland, Ohio. In 1884 the first practical trolley line was built
in Kansas City and from this time on horse- and mule-drawn cars were
doomed, except on West Street in New York City where they are still
used to hold down a _franchise_.

There were in 1912 about 41,000 miles of track operated by electricity
in the United States; over 76,000 passenger cars were in service and
12,100,000 passengers were carried, all of which goes to show that
there is money in electrical inventions for somebody.

_The Electric Locomotive._--The 1913 type of _electric locomotive_ used
on the New York Central is fifty-seven feet long, weighs 110 tons, has
eight motors of 325 horsepower each, which are mounted on four trucks
and driving eight axles. This powerful locomotive is capable of hauling
a train of 1200 tons at a speed of sixty miles an hour on a straight
level track. The stockholders of the General Electric Company of
Schenectady, N. Y., profited by their building.

_The Linotype._--The _linotype_ is a machine that is operated like
a typewriter and makes a _slug_ or a solid line of type from metal
type-bars each of which has a letter on it. These type-bars are then
properly spaced and melted type metal is run into the matrix they
form. This wonderful machine is the invention of Ottmar Mergenthaler
who began working on it in 1876 and completed the machine in 1886.
Thousands of linotype machines are in use at the present time and it
goes without saying that the inventor was richly rewarded for his hard
labors.

_Moving Pictures._--The _moving-picture_ industry, which is the third
largest in the United States, came into being through the following
inventions: In 1845 a toy called the _zoetrope_, or wheel-of-life,
was invented; it was so made that when a series of drawings showing
the different positions of, say, a horse in motion was viewed through
a number of vertical slits in a rapidly revolving cylinder the horse
would appear to be running. It was truly a moving picture.

The next step was taken by Eadweard Muybridge in 1877, who was the
first to make a series of instantaneous photographs of a horse in
motion, and in this way he showed the true position of the animal at
different instants of its gait, but since there was no exactness in
timing the intervals between the exposures of the dry plates--the film
had not yet been invented--they could not have been used for moving
pictures.

The photographic gelatine film having come into use, Edison, in 1893,
invented two machines, the _kinetograph_ which was a camera for taking
successive pictures of moving objects, and the _kinetoscope_ which
allowed the pictures made on the film by the kinetograph to be viewed.
The kinetoscope showed each picture on the film to the eye for about
¹/₄₀th of a minute, so that the figures seemed to move as in actual
life. And this is the way the moving-picture industry was born. It was
easy to combine a projecting lantern and a kinetoscope so that the
little photographs on the film could be thrown on a screen and enlarged
and this is the principle of all moving-picture machines as they are
now constructed.

The moving-picture business has taken a tremendous hold on the public
all over the world. This is shown by the fact that in 1914 the
distributers for three of the largest film makers handled 75 per cent.
of the films released and are said to have received $15,000,000 for
them. In 1915 the daily average attendance of moving-picture shows in
the United States was about 5,000,000 people.

[Illustration: FIG. 125. THE COLLINS WIRELESS TELEPHONE. SHOWN AT THE
MADISON SQUARE GARDEN, NEW YORK, ELECTRICAL SHOW, OCTOBER, 1908]

_The Wireless Telegraph._--The _wireless telegraph_ was invented by
William Marconi, who showed a set in operation, in 1896, between the
General Postoffice and the Thames embankment in London, the distance
being about 300 feet. Since that time he has been almost constantly
engaged in patent suits with infringers.

Since then the signaling range has been increased until now a regular
telegraph service without wires is carried on across the Atlantic. I
do not know how well the inventor fared financially but whatever the
amount he got, it was not nearly enough for his great work.

_The Wireless Telephone._--The _wireless telephone_ was invented by the
author of this book in 1899 when he telephoned without wires between
two stations in Narberth, Pa., a distance of about three blocks. During
the past year the human voice has been transmitted without wires from
Arlington, near Washington, D. C., eastward to Paris, France, and from
Arlington as far westward as Honolulu, Hawaii. Patent litigation,
patent hold-ups and government persecution have been my lot. I know
about the amount I made out of my invention but I won’t tell.

_The Aeroplane._--The _aeroplane_ was invented by the Wright Brothers,
Wilbur and Orville. They began their experiments in flying on the
sand-dunes of Kitty Hawk, N. C., in 1900. Their first efforts were made
with a glider fitted with elevation planes and after having developed
the balancing instinct they installed a gasoline motor in the glider
and this drove two propellers at the rear of the machine.

With this new born aeroplane they made the first motor-driven,
man-carrying flight in 1903--a flight that lasted a small fraction of a
minute. From this time on records and necks were broken by other fliers
who tried to outdo their rivals and undo themselves.




CHAPTER XII

PROFITABLE INFORMATION


~Design Patents.--~Should you invent, or devise a new and original
design for an object, be it a work of art, a fabric, a piece of jewelry
or even a machine, you can obtain a design patent if it has artistic
merit.

[Illustration: FIG. 126. ILLUSTRATION FOR A DESIGN PATENT, DRAWN ON A
SHEET OF CARD-BOARD SIZE 10 × 15 INCHES]

Design patents run for a term of 3½, or for 7, or for 14 years as you
wish and care to pay for. The patent attorney’s fees for writing the
specification, making the drawing and seeing the patent application
through the patent office is usually $20 regardless of the term it is
to run; the government fee is $10 for 3½ years, $15 for 7 years and $30
for 14 years, making the total cost of such patents $30, $35 and $50
respectively.


~Assignments.--~If you want to you may sell or assign a part or the
whole of your invention before you file an application for a patent,
or you may do the same thing while your application is pending in the
patent office.

Such an interest in your invention and patent rights may be disposed of
by a complete assignment, by granting territorial rights, by mortgage,
or by shop or other licenses. In whatever way the assignment, grant or
conveyance is made it must be recorded in the patent office or it will
not be valid.


~Caveats.--~A _Caveat_ can no longer be filed in the patent office,
the law relating to them having been repealed July 1, 1910. Before
this time an inventor who had not completed his invention could file
a _Caveat_ in the archives of the patent office where it was kept a
secret for one year, and the time could be renewed from year to year.

The purpose of a _Caveat_ was to give the inventor more time to work
out his invention and to be notified should any other inventor apply
for a patent on the same thing. He could then immediately file his own
patent application when an _interference_ would be declared between
them.


~Patent Office Fees.--~The following schedule of fees for patents and
prices for the various publications of the patent office are taken from
the _Rules of Practice_. These fees are required to be paid in advance.
All orders and moneys for the following fees should be sent to the
Commissioner of Patents, Washington, D. C.; except for _The Official
Gazette_ which should be sent to the Superintendent of Documents,
Government Printing Office, Washington, D. C.


RULES OF PRACTICE IN THE U. S. PATENT OFFICE

_Free on Request._

  On filing each original application for a patent, except
    in design cases                                              $15.00
  On issuing each original patent, except in design cases         20.00
  In design cases:
      For 3 years and 6 months                                    10.00
      For 7 years                                                 15.00
      For 14 years                                                30.00
  On every application for the reissue of a patent                30.00
  On filing each disclaimer                                       10.00
  On an appeal for the first time from the primary
    examiner to the examiners in chief                            10.00
  On every appeal from the examiners in chief to the
    Commissioner                                                  20.00
  For certified copies of patents if in print:
      For specification and drawing, per copy                       .05
      For the certificate                                           .25
      For the grant                                                 .50
      For certifying to a duplicate of a model                      .50
  For manuscript copies of records, for every 100 words
    or fraction thereof                                             .10
      If certified, for the certificate additional                  .25
  For 20-coupon orders, each coupon good for one copy
    of a printed specification and drawing, and receivable
    in payment for photographic prints                             1.00

  For 100 coupons in stub book                                     5.00

  For uncertified copies of the specifications and accompanying
    drawings of patents, if in print, each                          .05

  For the drawings, if in print                                     .05

  For copies of drawings not in print, the reasonable
    cost of making them.

  For photo prints of drawings, for each sheet of drawings:
      Size 10 by 15 inches, per copy                                .25
      Size 8 by 12½ inches, per copy                                .15

  For recording every assignment, agreement, power of attorney,
    or other paper, of 300 words or under                          1.00
      Of over 300 and under 1,000 words                            2.00
      For each additional 1,000 words or fraction thereof          1.00

  For abstracts of title to patents or inventions:
      For the search, one hour or less, and certificate            1.00
      Each additional hour or fraction thereof                      .50
      For each brief from the digest of assignments, of 200
        words or less                                               .20
      Each additional 100 words or fraction thereof                 .10

  For searching titles or records, one hour or less                 .50
      Each additional hour or fraction thereof                      .50

  For assistance to attorneys in the examination of
    publications in the Scientific Library, one hour or
    less                                                           1.00
      Each additional hour or fraction thereof                     1.00

  For copies of matter in any foreign language, for
    every 100 words or a fraction thereof                           .10

  For translation, for every 100 words or fraction thereof          .50

  The Official Gazette:
    Annual subscriptions                                           5.00
      For postage upon foreign subscriptions, except
      those from Canada and Mexico, $5 or
      more as required. Moneys received from
      foreign subscribers in excess of the subscription
      price of $5 will be deposited to
      the credit of the subscriber and applied to
      postage upon the subscription as incurred.


~Trade Marks.--~A _trade mark_ is any kind of a mark, sign, name or
picture, or a combination of these, by which a manufacturer, or a
dealer can mark the goods he makes or sells so that a consumer can
always know that the brand he is buying is genuine.

A registered trade mark gives the owner the sole right to use it and
any one else who uses or imitates it can be restrained from its further
use by injunction and sued for damages. After you have decided on
the trade mark you want to use to show that the product is of your
manufacture you should file an application to register the trade mark
just as you would for a patent.

[Illustration: FIG. 127. A REGISTERED TRADE MARK]

There are some kinds of words which you cannot have registered as a
trade mark and you may have other words in mind which have already
been registered in the patent office; nor can you register a trade
mark unless you have sold your goods outside of your own State. Patent
attorneys do not as a rule charge for a search of the trade mark
records where an application for registration is filed through them.

The patent office fee for registering a trade mark is $10; a patent
attorney generally charges $15 for preparing the specification and $5
additional for making the drawing which makes a total cost of $30 for a
trade mark. A registered trade mark remains in force for 20 years and
it may be renewed for another 20 years.


~Copyrights.--~A copyright is the sole right granted by law to authors
and artists to publish and dispose of their works for a term of 28
years when it may be renewed for 14 years more making 42 years in all.

A copyright may be had on written articles, books, lectures or other
oral addresses, on dramatic and musical compositions, photographs,
paintings, drawings, sculpture, plastic work, moving picture
photo-plays, moving pictures other than photo-plays, maps, prints and
pictorial illustrations.

A copyright cannot be had on trade marks, the names of companies,
newspapers, manufactured articles or on prints or labels which are to
be used for any kind of manufactured articles. Trade marks and patents
are granted for the above classes of work.

The general procedure for obtaining a copyright on the first named
subjects is the same but the _application forms_ issued by the
Copyright Office differ a little from each other in wording and you
should have the right one.

When you are ready to file an application for a copyright in the
United States send to the _Register of Copyrights_, Copyright Office,
Washington, D. C., for a copy of _Steps Necessary to Secure Copyright
Registration_ and also a copy of _Explanatory Circular_ No. 12,
entitled _Application Forms_, for which no charge is made. A reading of
these leaflets will tell you exactly how to obtain a copyright and also
the _application form_ to use.

When you have found from these the application form you need send
again to the Register of Copyrights for one or more of the application
forms, fill it in and send it and $1 by money order or bank-draft
made payable to the Register of Copyrights, together with a 10 cent
revenue stamp--for these are war times--and you will receive in turn a
certificate of copyright.

By copyrighting the thing yourself you will save just $9 for this is
the amount a patent attorney will charge you for filing it, and if this
isn’t driving screws with a hammer I’d like to know what it is.

The following is an application form for copyrighting a book:--

[Illustration: FIG. 128A. APPLICATION FOR COPYRIGHT OF A BOOK]

[Illustration: FIG. 128B. AFFIDAVIT ON BACK OF APPLICATION]


~Government Fees for Patents and Least Charges of Patent
Attorneys.--~The United States patent office fees for patents of
whatever nature and however simple or complicated, except for design
patents, are always the same, namely $15 for filing the application and
$20 which is payable when the patent is granted making a total cost
of $35. The patent attorneys’ fees may vary greatly but the following
table shows about what their least charges are:


UNITED STATES PATENTS

                             _Attorney’s              _Patent  _Total
                             Fees_        _Drawings_  Office   Cost of
                                                      Fees_    Patent_
  A simple mechanical                   }            }        }
    patent                    $30       }            }        }
  A simple electrical                   }  $5        }        }
    patent                    $30       }            }        }
  A simple chemical         }                        }        }
    patent                  }                        } $35    } $70
  A simple electro-chemical }                        }        }
    patent                  } $35                    }        }
  A simple composition      }                        }        }
    patent                  }                        }        }
  A simple process patent   }                        }        }


DESIGN PATENTS, ETC.

  Design Patent
      3½ year term          }           }
      7  year term          } $15       }  $5          $15      $35
      14 year term          }           }              $30      $50
  Trade Mark Registration     $15          $5          $10      $30
  Print and Label
    Registration              $14                       $6      $20
  Copyright                    $9                       $1      $10
  Assignment of Patents
    and Trade Marks            $5


~Foreign Patents.--~After you have applied for a patent on your
invention in the United States you should take out patents in foreign
countries. Sometimes indeed you will find a more ready sale abroad for
your invention, or the product of your invention, than you will right
here at home. In many of these countries a yearly tax is also charged
by the government. The costs given below for each country include both
the government and the attorney’s fees.

_Dominion of Canada._--In Canada a preliminary protection may be
secured for one year. A patent is issued for 6 years and at the
expiration of that time the patent may be extended for 6 years more and
then for another 6 years, making 18 years in all.

  Preliminary protection                                  $ 5
  Patent for 6-year term                                   45

_Great Britain._--A British patent includes England, Ireland, Scotland
and Wales. A _provisional patent_ which secures priority of invention
may be obtained for a term of 6 months. The complete British patent is
then issued for 14 years.

  Provisional specification                               $30
  Patent for 14 years                                      70

_France and Colonies._--The term of a French patent is 15 years. If the
invention it covers is not worked within 2 years after it is issued it
becomes public property.

  Patent for 15 years                                     $60

_Germany and Colonies._--A German patent includes Prussia, Saxony,
Bavaria and other kingdoms of the Empire. There are two classes of
patents issued and these are 1, the _technical patent_, which is issued
for 15 years, and 2, the _model patent_, which is issued for 6 years,
the first corresponding to the U. S. ordinary patent and the second to
the U. S. design patent.

  Technical patent, for 15 years                          $60
  Model patent, for 6 years                                35

_Austria and Hungary._--

  Patent in either country for 15 years. Fee is           $70

_Belgium._--Patent for 20 years. Fee is $40.

_Spain._--Patent for 20 years. Fee is $65.

_Italy._--Patent for 15 years. Fee is $65.

_Russia._--Patent for 15 years. Fee is $90.

_Denmark._--Patent for 15 years. Fee is $70.

_Norway and Sweden._--Patent for 15 years in each country. Fee is $70.

_Switzerland._--Patent for 15 years. Fee is $60.

_Portugal and Turkey._--Patent for 15 years. Fee is $100.

_Holland._--Has no patent laws.

_India._--Patent for 14 years. Fee is $80.

_Australian Commonwealth._--Includes Victoria, New South Wales,
Queensland, South Australia, Tasmania and West Australia. One patent
covers them all.

  Patent for 14 years                                    $100

_Japan and China._--Fee is $100.

_Africa._--Egypt, Natal and Transvaal, each $100. Cape Colony, $125.
Congo Free State, $130.

_Central America._--Costa Rica, $150. Guatemala, Honduras and
Nicaragua, each $225.

_West Indies._--Cuba, $90. Barbados, $100. Jamaica, $125. Trinidad,
$140. Bahama Islands, $150.

_South America._--United States of Colombia, $120. Brazil, $125. Peru
and Panama, $200. Venezuela, $220; and Chili, $230.




APPENDICES




APPENDIX A

SOME USEFUL MATHEMATICAL FORMULAS


  π = 3.14159 (π is a Greek letter pronounced Pi)

  _d_ = _diameter_ of a circle

  _r_ = _radius_ of a circle

  _p_ = _periphery_, or circumference of a circle

  The _area_ of a circle = πr²

  The _circumference_ of a circle = πd

                                p     p
  The _diameter_ of a circle = --- = ----
                                π    3.14

                              p      p
  The _radius_ of a circle = ---- = ----
                              2π    6.28

  The _surface_ of a sphere = 4πr² = πd²

                              4         1
  The _volume_ of a sphere = --- πr³ = --- πd³
                              3         6




APPENDIX B

THE METRIC OR DECIMAL SYSTEM


The _metric system_ is a French system of weights and measures much
used in the arts and sciences in every civilized country and as each
unit is multiplied or divided by 10 to obtain ascending or descending
values it is much more convenient to use than the older English system
of arbitrary measures.

The metric system is based on the _meter_, which is one-ten millionth
of the distance from the Earth’s equator to the North Pole. There are
five units, the four latter being derived from the meter and these are:

1. The _meter_ which is the unit of length and is about 3.280 feet in
length.

2. The _are_ which is the unit of surface and is 100 square meters in
area.

3. The _liter_ which is the unit of capacity and is 1 cubic decimeter,
which is equal to 1.0567 United States quarts.

4. The _stere_ which is the unit of solidity and is equal to 1 cubic
meter.

5. The _gram_ is the unit of weight and is the weight of 1 cubic
centimeter of distilled water at its maxim density.




APPENDIX C

METRIC MEASURES OF LENGTH AND VALUES IN INCHES


            { Millimeter (mm) =      0.001 m. =   0.03937 inch
  Divisions { Centimeter (cm) =      0.01  m. =   0.3937 inch
            { Decimeter  (dm) =      0.1   m. =   3.937 inches
         Unit Meter      (m)  =      1.    m. =  39.37 inches
            { Dekameter  (Dm) =     10.    m. = 393.7 inches
  Multiples { Hektometer (Hm) =    100.    m. = 328. feet and 1 inch
            { Kilometer  (Km) =  1,000.    m. =   0.62326 mile
            { Myriameter (Mm) = 10,000.    m. =   6.2326 miles




APPENDIX D

METRIC MEASURES OF WEIGHT AND VALUES IN ENGLISH WEIGHT


            { Milligram (mg) =      0.001 g =  0.0154 grain  avoirdupois
  Divisions { Centigram (cg) =      0.01  g =  0.1543 grain     “
            { Decigram  (dg) =      0.1   g =  1.5432 grain     “
        Unit  Gram      (g)  =      1     g = 15.432  grains    “
            { Dekagram  (Dg) =     10     g =  0.3527 ounce     “
  Multiples { Hektogram (Hg) =    100     g =  3.5274 ounces    “
            { Kilogram  (Kg) =  1,000     g =  2.2046 pounds    “
            { Myriagram (Mg) = 10,000     g = 22.046  pounds    “




APPENDIX E

TO CHANGE METRIC TO ENGLISH MEASURE AND VICE VERSA


  _To Change_             _To_             _Multiply by_
  Inches                 Centimeters          2.54
  Feet                   Meters               0.3048
  Miles                  Kilometers           1.6093
  Square Inches          Square Centimeters   6.4516
  Square Feet            Square Meters        0.0929
  Square Yards           Square Meters        0.8361
  Cubic Inches           Cubic Centimeters   16.3872
  Cubic yards            Cubic Meters         0.7646
  Fluid ounces           Cubic Centimeters   29.574
  Quarts                 Liters               0.9464
  Ounces (avoirdupois)   Grams               28.3495
  Grains                 Milligrams          64.789
  Pounds (avoirdupois)   Kilograms            0.4536
  Meters                 Inches              39.37
  Meters                 Feet                 3.2808
  Kilometers             Miles                0.6213
  Square Centimeters     Square Inches        0.155
  Square Meters          Square Yards         1.196
  Cubic Centimeters      Cubic Inches         0.0610
  Cubic Meters           Cubic Yards          1.308
  Cubic Centimeters      Fluid Ounces         0.0344
  Liters                 Quarts               1.0567
  Grams                  Grains              15.4324
  Kilograms              Pounds               2.204




APPENDIX F

SIZES OF TWIST DRILLS FOR TAPS OR SCREWS


  _No. of Drill_  _No. of Tap  _No. of Threads
                   or Screw_     to the Inch_

  Use 38 for                4--36
   “  32  “                 6--32
   “  28  “                 8--32
   “  22  “                10--24
   “  13  “                12--24




APPENDIX G

SIZES OF TAPS AND DIES


  _No. of Tap or Die_   _Threads to Inch_
           4                   36
           6                   32
           8                   32
          10                   24
          12                   24




APPENDIX H

SIZES OF MACHINE SCREWS AND NUTS


Machine screws and nuts are numbered the same as dies and taps.




APPENDIX I

REDUCING FRICTION


When two bodies are rubbed together the motion is opposed by a force
called _friction_. When two surfaces slide against each other the
friction between them is proportional to the force pressing them
together. The _amount_ of friction depends upon the pressure of the
bodies, the roughness of their surfaces and also slightly on their
_adhesion_. The friction is the same regardless of the speed with which
the surfaces slide over each other.

The _co-efficient of friction_ is the measure of friction and this is
found by dividing the _force of friction_ by the _force pressing the
surfaces together_. Here are a few co-efficients of sliding friction:

                                                     _Per cent._
  Oak on Oak with Fibers parallel without lubricant    0.42
  Oak on Oak with Fibers parallel rubbed with soap     0.16
  Cast Iron on Oak                                     0.42
  Cast Iron on Cast Iron, not lubricated               0.15
  Cast Iron on Cast Iron, lubricated                   0.10
  Iron on Brass                                        0.16
  Brass on Brass                                       0.20
  Iron on Bronze, without lubricant                    0.25
  Iron on Bronze, thoroughly lubricated                0.06
  Cast Iron Wheels on Rails (Rolling Friction)         0.004
  Ball Bearings (Rolling Friction)                     0.001




APPENDIX J

WEIGHT OF CASTINGS COMPARED WITH WOOD PATTERNS


The following table shows what the weight of a casting will be compared
with the weight of the wood pattern from which it was made, less the
weight of the _core point_, or piece projecting from the pattern to
support it.

  ===============+===============================================
  A Wood Pattern |
    Weighing     |           Will Make a Casting Weighing
    One Pound    |
  ---------------+-----------+--------+--------+--------+--------
    Pattern of   | Cast Iron | Brass  | Copper | Bronze | Zinc
                 |   Pounds  | Pounds | Pounds | Pounds | Pounds
  ---------------+-----------+--------+--------+--------+--------
  Pine           |   14      |  15.8  |  16.7  |  16.3  |  13.5
  Beech          |    9.7    |  10.9  |  11.4  |  11.3  |   9.1
  Oak            |    9      |  10.1  |  10.4  |  10.3  |  12.9
  Birch          |   10.6    |  11.9  |  12.3  |  12.2  |  10.2
  Mahogany       |   11.7    |  13.2  |  13.7  |  13.5  |  11.2
  Brass          |    0.84   |   0.95 |   0.99 |   0.98 |   0.81
  ---------------+-----------+--------+--------+--------+--------




APPENDIX K

GEARS AND GEARINGS


A _spur-gear_ is a gear with teeth cut on its _periphery_, that is an
ordinary cog-wheel. _Miter gears_ are two _bevel gears_ of the same
diameter which run together. A large miter gear will not mesh with a
small miter gear nor with another bevel gear in the proper manner.
Miter and bevel gears cannot be interchanged with other sets like spur
gears.

[Illustration: FIG. 129. CROSS SECTION OF GEAR]

All miter gears that you buy ready cut are made so that their shafts
run at right angles to each other as shown in Fig. 129, but you can
have them cut to order to run at any angle you want.

To find the _pitch_, _pitch diameter_, _circular pitch_, etc., of both
spur and bevel gears use these rules:

  π = 3.14159
  _p_ = pitch
  _n_ = number of teeth
  _pd_ = pitch diameter
  _od_ = outside diameter
  _cp_ = circular pitch

  _To Find the Pitch_:

         n
    p = ----
         pd

  _To Find the Number of Teeth_:

    n = p × pd

  _To Find the Pitch Diameter_:

          n
    pd = ---
          p

  _To Find the Outside Diameter of Spur Wheels_:

         (2 + n)
    od = -------
            p

  _To Find the Circular Pitch_:

          π
    cp = ----
          pd

  _To Find the Distance Between the Centers of Two Spur Gears_:

    (n¹ + n²)
    ---------
        2
    ---------
        p

  Where n¹ + n² = the sum of the teeth of both gears.




APPENDIX L

SOME USEFUL ALLOYS


  Name of Alloy   Parts     Parts    Parts    Parts      Parts
                    of       of       of       of         of
                  Copper     Tin     Zinc     Lead       Other
                                                         Metals
  --------------+--------+--------+--------+--------+--------------
  Gun Metal     | 91     |  9     |        |        |
  Bell Metal    | 75     | 25     |        |        |
  Phosphor      |        |        |        |        |
  Bronze        | 92½    |  7     |        |        | ½ phosphorus
  Aluminum      |        |        |        |        |
  Bronze        | 90     |        |        |        | 10 aluminum
  Common        |        |        |        |        |
  Brass         | 66⅔    |        | 33⅓    |        |
  Brazing Metal |        |        |        |        |
  (soft)        | 50     | 12½    | 37½    |        |
  German        |        |        |        |        |
  Silver        | 60     |        | 20     |        | 20 nickel
  Common        |        |        |        |        |
  Solder        |        | 50     |        | 50     |
  Fine Solder   |        | 66⅔    |        | 33⅓    |
  Babbitt Metal | 3      | 89     |        |        | 8 antimony
  Pewter        |        | 80     |        | 20     |
  Type Metal    |        |        |        | 80     | 20 antimony
  Aluminum      |        |        |        |        |
  Solder        | 95     |        |        |        | 5 bismuth
  --------------+--------+--------+--------+--------+--------------

  Magnetic Alloy.--An alloy that has strong magnetic properties
                   is made of 25 parts of manganese, 14 parts of
                   aluminum and 61 parts of copper, yet none of
                   these metals are even slightly magnetic.




APPENDIX M

SOME HARD SOLDERS


Hard solders melt only at red heat and are used for soldering gold,
silver, brass and other metals where a good strong joint is needed.

  -----------+--------+--------+--------+--------+------------
  Metal to be|Parts of|Parts of|Parts of|Parts of|  Parts of
  Soldered   |  Gold  | Brass  |Silver  |  Zinc  |Other Metals
  -----------+--------+--------+--------+--------+------------
  Gold       | 66.67  |        | 22.22  |        |11.11 copper
  Silver     |        | 43.75  | 50     |  6.25  |
  Brass      |        | 87.5   |        | 12.5   |
  -----------+--------+--------+--------+--------+------------




APPENDIX N

HIGH SPEED STEEL


A special steel alloy which is largely used for turning tools in
_engine lathes_ and which will cut ordinary steel when the latter is
revolved at a high surface velocity is called _high speed steel_. A
tool made of high speed steel will not lose its _temper_ and will keep
its cutting edge hour after hour if they are kept cool by a stream
of water running on them. A good high speed steel for machine tools
is known by the trade name of _blue-chip_ and is manufactured by the
Firth-Sterling Steel Company of Pittsburg, Pa.




APPENDIX O

SOME ELECTRICAL SYMBOLS, TERMS AND FORMULAS


  Symbols    Terms

  E or EMF = Electromotive Force
  I        = Intensity of Current
  R        = Resistance
  C        = Capacity
  Q        = Quantity of Current
  [F]      = Magneto-Motive Force
  [R]      = Reluctance (magnetic resistance)
  µ        = Magnetic Permeability
  W        = Electric Energy
  P        = Electric Power


SOME DEFINITIONS

 E or EMF, or _electromotive force_, is the force that moves a current
 through a conductor.

 I, or _intensity of current_, or _current_ as it is called for short,
 is the flow of electricity through a conductor.

 R, or _resistance_ is that property of a conductor which opposes the
 flow of the current.

SOME ELECTRICAL UNITS

  _Practical Units._          _Electrical Quantity_

          Volt              is the practical unit of EMF
          Ampere            is the practical unit of I
          Ohm               is the practical unit of R
          Watt              is the practical unit of P


OHM’S LAW

Since the intensity of an electric current varies _directly_ as the
electromotive force and _inversely_ as the resistance, if you know the
value of any two of the above units you can easily find the third.

             Volts           E
  Amperes = -------, or I = ---
             Ohms            R

                          Current             I
  Electromotive Force = ------------, or E = ---
                         Resistance           R

                Electromotive Force           E
  Resistance = ---------------------, or R = ---
                      Current                 I

_To Find Power of an Electric Current in Terms of Horse Power_

   One Watt = 1 volt × 1 ampere
  746 Watts = 1 horse power.

To find the power of an electric current in terms of horse-power, find
the number of watts by multiplying the volts by the amperes and divide
the watts by 746 and the result will give you the horse-power of the
current.




APPENDIX P

NUMBER, DIAMETER, CAPACITY, WEIGHT,
AND RESISTANCE OF PURE COPPER WIRE


  =========+==========+===========+==========+=======================
    Gage,  | Diameter | Sectional | Capacity |        OHMS
   B. & S. |    in    |  Area in  |    in    +-----------+-----------
     No.   | 1000ths. | Circular  |  Amperes | Per 1,000 | Per Mile
           |          |   Mils.   |          |   Feet    |
  ---------+----------+-----------+----------+-----------+-----------
    0000   |  .460    | 211600.   |   312.   |     .0490 |     .2590
     000   |  .40964  | 167805.   |   262.   |     .0618 |     .3266
      00   |  .3648   | 133079.   |   220.   |     .0780 |     .4118
       0   |  .32486  | 105534.   |   185.   |     .0983 |     .5190
       1   |  .2893   |  83694.   |   156.   |     .1240 |     .6549
       2   |  .25763  |  66373.   |   131.   |     .1564 |     .8258
       3   |  .22942  |  52634.   |   110.   |     .1972 |    1.0414
       4   |  .20431  |  41473.   |    92.3  |     .2486 |    1.313
       5   |  .18194  |  33102.   |    77.6  |     .3136 |    1.655
       6   |  .16202  |  26251.   |    65.2  |     .3954 |    2.088
       7   |  .14428  |  20817.   |    54.8  |     .4987 |    2.633
       8   |  .12849  |  16510.   |    46.1  |     .6529 |    3.3
       9   |  .11443  |  13094.   |    38.7  |     .7892 |    4.1
      10   |  .10189  |  10382.   |    32.5  |     .8441 |    4.4
      11   |  .09074  |   8234.   |    27.3  |    1.254  |    6.4
      12   |  .08080  |   6530.   |    23.   |    1.580  |    8.3
      13   |  .07196  |   5178.   |    19.3  |    1.995  |   10.4
      14   |  .06408  |   4107.   |    16.2  |    2.504  |   13.2
      15   |  .05706  |   3257.   |    13.6  |    3.172  |   16.7
      16   |  .05082  |   2583.   |    11.5  |    4.001  |   23.
      17   |  .04525  |   2048.   |     9.6  |    5.04   |   26.
      18   |  .04030  |   1624.   |     8.1  |    6.36   |   33.
      19   |  .03589  |   1288.   |          |    8.25   |   43.
      20   |  .03196  |   1021.   |          |   10.12   |   53.
      21   |  .02846  |    810.   |          |   12.76   |   68.
      22   |  .02534  |    642.   |          |   16.25   |   85.
      23   |  .02257  |    509.   |          |   20.30   |  108.
      24   |  .0201   |    404.   |          |   25.60   |  135.
      25   |  .0179   |    320.   |          |   32.2    |  170.
      26   |  .01594  |    254.   |          |   40.7    |  214.
      27   |  .01419  |    201.   |          |   51.3    |  270.
      28   |  .01264  |    159.8  |          |   64.8    |  343.
      29   |  .01125  |    126.7  |          |   81.6    |  432.
      30   |  .01002  |    100.5  |          |  103.     |  538.
      31   |  .00892  |     79.7  |          |  130.     |  685.
      32   |  .00795  |     63.   |          |  164.     |  865.
      33   |  .00708  |     50.1  |          |  206.     | 1033.
      34   |  .00630  |     39.74 |          |  260.     | 1389.
      35   |  .00561  |     31.5  |          |  328.     | 1820.
      36   |  .005    |     25.   |          |  414.     | 2200.
      37   |  .00445  |     19.8  |          |  523.     | 2765.
      38   |  .00396  |     15.72 |          |  660.     | 3486.
      39   |  .00353  |     12.47 |          |  832.     | 4395.
      40   |  .00314  |      9.88 |          | 1049.     | 5542.
  ---------+----------+-----------+----------+-----------+-----------




APPENDIX P, continued

NUMBER, DIAMETER, CAPACITY, WEIGHT,
AND RESISTANCE OF PURE COPPER WIRE


  =======+============+=========================+=======================
   Gage, |     OHMS   |           FEET          |         POUNDS
  B. & S.+------------+------------+------------+----------+------------
    No.  | Per Pound  | Per Pound  |   Per Ohm  | Per 1,000| Per Ohm
         |            |            |            |    Feet  |
  -------+------------+------------+------------+----------+------------
    0000 |     .00007 |     1.5612 | 20497.7    | 640.59   | 12987.
     000 |     .00012 |     1.9687 | 16255.27   | 507.85   |  8333.
      00 |     .00019 |     2.4824 | 12891.37   | 402.83   |  5263.
       0 |     .00031 |     3.1303 | 10223.08   | 319.45   |  3225.
       1 |     .00049 |     3.9471 |  8107.49   | 253.34   |  2041.
       2 |     .00078 |     4.9772 |  6429.58   | 200.91   |  1228.
       3 |     .00125 |     6.2765 |  5098.61   | 159.32   |   800.
       4 |     .00198 |     7.9141 |  4043.6    | 126.35   |   505.
       5 |     .00314 |     9.9798 |  3206.61   | 100.20   |   318.
       6 |     .00499 |    12.5847 |  2542.89   |  79.462  |   200.
       7 |     .00792 |    15.8696 |  2015.51   |  63.013  |   126.
       8 |     .0125  |    20.0097 |  1599.3    |  49.976  |    80.
       9 |     .0197  |    25.229  |  1268.44   |  39.636  |    50.
      10 |     .0270  |    31.8212 |  1055.66   |  31.426  |    37.
      11 |     .0501  |    40.1202 |   797.649  |  24.924  |    20.
      12 |     .079   |    50.5906 |   632.555  |  19.766  |    12.65
      13 |     .127   |    63.7948 |   501.63   |  15.674  |     7.87
      14 |     .200   |    80.4415 |   397.822  |  12.435  |     5.00
      15 |     .320   |   101.4365 |   315.482  |   9.859  |     3.12
      16 |     .512   |   127.12   |   250.184  |   7.819  |     1.95
      17 |     .811   |   161.29   |   198.409  |   6.199  |     1.23
      18 |    1.29    |   203.374  |   157.35   |   4.916  |      .775
      19 |    2.11    |   256.468  |   124.777  |   3.899  |      .473
      20 |    3.27    |   323.399  |    98.9533 |   3.094  |      .305
      21 |    5.20    |   407.815  |    78.473  |   2.452  |      .192
      22 |    8.35    |   514.193  |    62.236  |   1.945  |      .119
      23 |   13.3     |   648.452  |    49.3504 |   1.542  |      .075
      24 |   20.9     |   817.688  |    39.1365 |   1.223  |      .047
      25 |   32.2     |  1031.038  |    31.0381 |    .9699 |      .030
      26 |   52.9     |  1300.180  |    24.6131 |    .7692 |      .0187
      27 |   84.2     |  1639.49   |    19.5191 |    .6099 |      .0118
      28 |  134.      |  2067.364  |    15.4793 |    .4807 |      .0074
      29 |  213.      |  2606.959  |    12.2854 |    .3835 |      .0047
      30 |  338.      |  3287.084  |     9.7355 |    .3002 |      .0029
      31 |  539.      |  4414.49   |     7.7214 |    .2413 |      .0018
      32 |  856.      |  5226.915  |     6.1224 |    .1913 |      .0011
      33 | 1357.      |  6590.41   |     4.8557 |    .1517 |      .00076
      34 | 2166.      |  8312.8    |     3.8496 |    .1204 |      .00046
      35 | 3521.      | 10481.77   |     3.0530 |    .0956 |      .00028
      36 | 5469.      | 13214.16   |     2.4217 |    .0757 |      .00018
      37 | 8742.      | 16659.97   |     1.9208 |    .0600 |      .00011
      38 |13722.      | 21013.25   |     1.5229 |    .0475 |      .00007
      39 |21896.      | 26496.237  |     1.2077 |    .0375 |      .00004
      40 |34823.      | 33420.63   |     0.9798 |    .0299 |      .00002
  -------+------------+------------+------------+----------+------------




APPENDIX Q

NUMBER OF TURNS OF WIRE THAT CAN BE WOUND IN A GIVEN SPACE


  ======+===============================+===============================
        |             COTTON            |              SILK
        +---------------+---------------+---------------+---------------
        |    SINGLE     |    DOUBLE     |    SINGLE     |    DOUBLE
  No. B +-------+-------+-------+-------+-------+-------+-------+-------
  & S.  |       |       |       |       |       |       |       |
  or    |       |       |       |       |       |       |       |
  Ameri-|  Per  |  Per  |  Per  |  Per  |  Per  |  Per  |  Per  |  Per
  can   | Square| Square| Square| Square| Square| Square| Square| Square
  Gage  |  Inch.|  Qu.  |  Inch.|  Qu.  |  Inch.|   Qu. |  Inch.|   Qu.
        |       | Inch  |       | Inch  |       | Inch  |       |  Inch
  ------+-------+-------+-------+-------+-------+-------+-------+-------
     20 |    676|    42 |   576 |    36 |    841|    52 |    676|    42
     21 |    842|    53 |   625 |    39 |    961|    60 |    842|    53
     22 |  1.024|    64 |   729 |    45 |  1.225|    76 |  1.024|    64
     23 |  1.024|    81 |   900 |    56 |  1.521|    95 |  1.296|    81
     24 |  1.600|   100 | 1.089 |    68 |  1.936|   121 |  1.600|   100
     25 |  1.849|   115 | 1.296 |    81 |  2.304|   144 |  1.849|   115
     26 |  2.209|   138 | 1.440 |    90 |  2.916|   182 |  2.209|   138
     27 |  2.500|   156 | 1.600 |   100 |  3.249|   206 |  2.500|   156
     28 |  3.025|   189 | 1.849 |   115 |  4.096|   254 |  3.025|   189
     29 |  3.481|   218 | 2.025 |   126 |  4.761|   297 |  3.481|   218
     30 |  4.356|   272 | 2.500 |   156 |  6.400|   400 |  4.356|   272
     31 |  5.001|   315 | 2.704 |   169 |  7.769|   485 |  5.041|   315
     32 |  5.929|   370 | 3.025 |   189 |  9.025|   564 |  5.929|   370
     33 |  7.089|   443 | 3.481 |   218 | 11.025|   689 |  7.089|   443
     34 |  7.769|   485 | 3.600 |   225 | 12.321|   770 |  7.769|   485
     35 |  8.100|   506 | 3.844 |   240 | 13.689|   855 |  8.100|   506
     36 | 10.000|   625 | 4.356 |   272 | 17.689| 1.105 | 10.000|   625
     37 | 11.025|   689 | 4.761 |   297 | 20.164| 1.240 | 11.025|   689
     38 | 12.321|   770 | 5.041 |   315 | 23.716| 1.482 | 12.321|   770
     39 | 13.689|   855 | 5.476 |   342 | 27.556| 1.722 | 13.689|   855
     40 | 15.625|   976 | 5.929 |   370 | 32.761| 2.047 | 15.625|   976
  ------+-------+-------+-------+-------+-------+-------+-------+-------
                                                         (W. J. Clarke.)




APPENDIX R

PRICES OF SINGLE AND DOUBLE SILK AND COTTON COVERED MAGNET WIRE

PRICE PER POUND


  --------+----------------+----------------
  Size by |    Single      |    Double
  B. & S. |    Covered.    |    Covered.
   Gage   +--------+-------+--------+-------
          | Cotton | Silk  | Cotton | Silk
  --------+--------+-------+--------+-------
      16  |        | $0.80 |        | $1.02
      17  |        |   .82 |        |  1.04
      18  |        |   .84 |        |  1.06
      19  |        |   .86 |        |  1.08
      20  |  $0.58 |   .88 |  $0.64 |  1.12
      21  |    .60 |   .90 |    .70 |  1.15
      22  |    .62 |   .92 |    .74 |  1.22
      23  |    .65 |   .96 |    .78 |  1.28
      24  |    .68 |  1.02 |    .84 |  1.38
      25  |    .73 |  1.10 |    .92 |  1.48
      26  |    .80 |  1.20 |   1.00 |  1.65
      27  |    .86 |  1.30 |   1.10 |  1.85
      28  |    .92 |  1.40 |   1.20 |  2.00
      29  |    .98 |  1.53 |   1.30 |  2.22
      30  |   1.08 |  1.70 |   1.42 |  2.56
      31  |   1.19 |  1.92 |   1.54 |  3.08
      32  |   1.27 |  2.16 |   1.64 |  3.40
      33  |   1.44 |  2.46 |   1.88 |  4.00
      34  |   1.73 |  2.90 |   2.20 |  4.60
      35  |   1.86 |  3.38 |   2.67 |  5.28
      36  |   2.12 |  3.93 |   3.00 |  5.98
      37  |   2.70 |  4.66 |   4.30 |  7.37
      38  |   3.60 |  5.58 |   5.70 |  8.43
      39  |   4.70 |  6.76 |   7.20 |  9.75
      40  |   6.00 |  8.14 |   9.00 | 11.53
  --------+--------+-------+--------+-------

There is a discount of about 50 per cent. on the above prices though
this is subject to change.




APPENDIX S

A LIST OF SOME CHEMICAL ELEMENTS AND THEIR SYMBOLS


  Element   Symbol
  Aluminum      Al
  Antimony      Sb
  Argon          A
  Arsenic       As
  Barium        Bi
  Boron          B
  Bromine       Br
  Cadmium       Cd
  Calcium       Ca
  Carbon         C
  Chlorine      Cl
  Chromium      Cr
  Cobalt        Co
  Copper        Cu
  Fluorine       F
  Gold          Au
  Helium        He
  Hydrogen       H
  Iodine         I
  Iron          Fe
  Lead          Pb
  Lithium       Li
  Magnesium     Mg
  Manganese     Mn
  Mercury       Hg
  Nickel        Ni
  Nitrogen       N
  Oxygen         O
  Phosphorus     P
  Potassium      K
  Platinum      Pt
  Silicon       Si
  Silver        Ag
  Sodium        Na
  Strontium     Sr
  Sulphur        S
  Tin           Sn
  Zinc          Zn




APPENDIX T

THE COMMON NAMES OF SOME CHEMICALS


    Common Name          Chemical Name

  Alum                 Sulphate of ammonium, or potassium, etc.
  Aqua fortis          Nitric acid
  Aqua regia           Concentrated nitric and hydrochloric acid mixed.
  Baking soda          Sodium carbonate
  Calomel              Mercurious chloride
  Carbolic acid        Phenol
  Caustic potash       Potassium hydroxide
  Caustic soda         Sodium hydroxide
  Chalk                Calcium carbonate
  Copperas             Ferrous sulphate
  Corrosive sublimate  Mercuric chloride
  Cream of tartar      Potassium bitartrate
  Epsom salts          Magnesium sulphate
  Fire damp            Methane
  Fool’s gold          Iron pyrites
  Glauber’s salt       Sodium sulphate
  Grape sugar          Glucose; a carbohydrate
  Hartshorn            Aqueous solution of ammonia
  Jeweler’s putty      Tin oxide
  Laughing gas         Nitrous oxide
  Lime                 Calcium oxide
  Lunar caustic        Silver nitrate
  Mosaic gold          Tin bisulphide
  Muriatic acid        Hydrochloric acid
  Monsel’s salts       Basic ferric sulphate
  Plaster of Paris     Calcium sulphate
  Realgar              Red arsenic sulphide
  Red lead             Lead oxide
  Rochelle salt        Sodium potassium tartrate
  Royal water          See Aqua regia
  Sal ammoniac         Ammonium chloride
  Salt (common)        Sodium chloride
  Sal soda             Sodium carbonate
  Salt of tartar       Potassium carbonate
  Saltpeter            Potassium nitrate
  Salts of lemon       Oxalic acid
  Slacked lime         Calcium hydrate
  Soda                 Sodium carbonate
  Spirits of salt      Hydrochloric acid
  Sugar of lead        Lead acetate
  Sugar of milk        Lactose
  Tartar emetic        Potassium antimonious tartrate
  Verdigris            Copper acetate
  Vermilion            Mercuric sulphide
  Vinegar              Dilute acetic acid
  Vitriol, blue        Copper sulphate
  Vitriol, green       Ferrous sulphate
  Vitriol, oil of      Sulphuric acid
  Vitriol, white       Zinc sulphate
  Volatile alkali      Ammonia
  Washing soda         Sodium carbonate
  White lead           Lead carbonate
  Zinc white           Zinc sulfid




APPENDIX U

THE FOUR CHIEF THERMOMETRIC SCALES


[Illustration: FIG. 130. THE FOUR CHIEF THERMOMETRIC SCALES: RÉAUMUR,
ABSOLUTE, FAHRENHEIT AND CENTIGRADE]

There are four different thermometer scales used for measuring
temperature and these are (1) the _Fahrenheit_ scale which is widely
used for all ordinary purposes; (2) the _Centigrade_ which is the
standard scale used for scientific work since it is based on the
decimal system; (3) the _Réaumur_ scale which is largely used in
Germany, and (4) the _absolute_ scale which is reckoned from _absolute
zero_, that is the point at which there is absolutely no heat. It
is about 461 degrees Fahr., 274 degrees centigrade, and 219 degrees
Réaumur below the zero of these scales.




SOME WORDS AND TERMS USED IN THIS BOOK


 _Accelerate._--To hurry or speed up the usual slow state of events.

 _Actuate._--(1) To put into action. (2) Means by which anything is
 started to move. (See Operate).

 _Adhesion._--A force which makes certain bodies stick together.

 _Aërial Wire._--An elevated wire used to send out and to receive
 electric waves for wireless telegraphy and wireless telephony.

 _Affidavit._--A sworn statement made before a notary public or other
 legal authority.

 _Agent._--(1) A canvasser. (2) One who acts as a salesman or in any
 capacity for another.

 _Amend._--To change or correct, as to _amend_ a claim in a patent.

 _Analysis._--See Chemical decomposition.

 _Arbor._--An axle, spindle, shaft or mandrel.

 _Archives._--A place in which official papers are kept and held secret.

 _Arlington wireless station._--A high powered wireless station at
 Arlington, Va., across the river from Washington, D. C.

 _Assignment._--To transfer to another a right or interest.

 _Attest._--To witness or to sign an oath that a thing is true.

 _Automatic._--A machine which performs certain operations of its own
 accord.

 _Aviation._--The art of flying.

 _Axis._--An imaginary line on or around which a body turns. (Plural
 Axes.)

 _Basic principle._--The first source or cause of a thing.

 _Biologist._--One who knows something about the science of life and
 living things.

 _Broker._--One who acts as an agent to negotiate purchases and make
 sales on a commission, as a _stock-broker_, _coffee-broker_, etc.

 _Capital._--Wealth that is used in or can be had for business.

 _Capital Stock._--The shares of a company that are sold to furnish
 funds with which to transact business.

 _Capitalize._--To fix a value on the stock of a company.

 _Case._--An application pending in the patent office.

 _Cause._--A suit or action over patent rights which is conducted in a
 court.

 _Certified copy._--A paper or a copy of a paper that has been sworn to
 before a notary to prove it to be the original or an exact copy of the
 original.

 _Chemical Combination._--(1) The atomic union of chemicals. (2) A
 compound of chemical elements.

 _Chemical Decomposition._--The separation of a compound with its
 original elements.

 _Circularize._--To send out circulars to a list of names.

 _Cite._--To quote a reference to an authority.

 _Citation._--An article or patent quoted by a patent examiner as a
 basis for the rejection of a patent application or of a claim.

 _Claim._--The last part of a patent specification in which the
 inventor clearly and specifically sets forth what his invention
 consists of and what he demands to have protected by a patent.

 _Claim, Broad._--(1) A _broad claim_ is one in which the inventor
 claims everything in sight and usually more than he is entitled to.
 (2) It is easy to write a broad claim but hard to get it allowed.

 _Claim, Narrow._--(1) A _narrow_, or _limited claim_ is one in which a
 patent attorney puts in so many elements or parts that the combination
 is bound to be patentable. (2) Such a claim has no value because it is
 easy for another to change an element or a part when the combination
 no longer infringes. (3) The hardest thing that an inventor has to
 contend with is to get a claim written so that it will stand in court.

 _Coincide._--Exactly corresponding to or meeting.

 _Conceive._--To get an idea.

 _Commission Merchant._--A man who stands between the manufacturer and
 the wholesaler and who gets a percentage on the amount of goods that
 change hands.

 _Commissioner of Patents._--The head, front and center of the patent
 office.

 _Concentric Circles._--Circles drawn within circles and all of them
 having the same center.

 _Corporation._--(1) A company. (2) An imaginary person invented by law
 and formed of one or more real persons banded together to transact
 business.

 _Correspondent._--(1) An associate. (2) A lawyer that carries on his
 business with another lawyer at a distance.

 _Consumer._--The last buyer and the user of an article or a device.

 _Cross-section._--See Drawing, Cross-section.

 _Counsel._--A patent attorney who is qualified to prosecute patent
 cases in court.

 _Data._--Information that is known or may be had.

 _Deductive Proof._--That form of thought by which an idea used as a
 starting point is brought to a conclusion by known principles and
 facts. (See Inductive Discovery.) Inductive discovery is the raw idea
 and does not lead up to certainty, whereas deductive proof does.

 _Degree._--(1) One three hundred and sixtieth part of a circle. (2)
 The unit of angular measurement.

 _Detailed Drawing._--See Drawing, Detailed.

 _Device._--(1) An apparatus or an instrument, or a machine or any part
 of any of them. (2) Any scheme for producing a desired result.

 _Die._--A steel tool having a sharp edge for cutting out special
 designs in paper, metals, etc.

 _Directors._--Members of a company chosen to direct its business.

 _Disclose._--(1) To make known. (2) To give up the secret of your
 invention.

 _Display ad._--An advertisement in which larger type is used than for
 the reading matter of the paper.

 _Dividends._--Money resulting from profits and which are distributed
 among the shareholders.

 _Drawing, Free Hand._--Pictures drawn without measurements or the aid
 of instruments.

 _Drawing, Working._--A drawing of a part, device or machine made to
 scale so that a mechanic can work from it.

 _Drawing, Cross Section._--A drawing of an object as though it had
 been cut in two in order to show its inside construction.

 _Drawing, Detail._--A drawing of any part of a device or a machine
 made large enough to show everything no matter how small.

 _Drawing, Perspective._--A drawing of a solid object on a flat surface
 so that it seems to stand out in space like the object itself.

 _Drawing, Isometric perspective._--See Isometric Perspective.

 _Du Ponts._--A firm at Wilmington, Delaware, who manufactures
 gun-powder and other explosives.

 _Efficient._--That which works the best with the greatest economy.

 _Element._--(1) A _chemical element_ is a form of matter which cannot
 be decomposed. (2) A _mechanical element_ is a single part of a device
 or a machine.

 _Electrolytic._--The decomposition of a chemical compound by an
 electric current.

 _Electroplating._--Depositing one metal on another metal by an
 electric current.

 _Electrotype._--A duplicate of type or cuts for printing, the body of
 which is of type-metal and the face of copper which has been deposited
 by an electric current.

 _Electrolytic._--Decomposition of a substance, or a solution by means
 of an electric current.

 _Electrolysis._--About the same as _electrolytic_.

 _Elementary._--Simple; primary.

 _Electro-Chemistry._--Chemistry in which electricity is used.

 _Engine lathe._--A large and accurate screw cutting lathe fitted with
 all known attachments.

 _Entering Edge._--The front edge of the main plane of an aeroplane.

 _Ether._--A substance filling all space and in, by and through which
 light, electricity and magnetism acts and travels.

 _Evidence of conception._--A signed and sealed statement made at the
 time or shortly after you get the big idea which will serve as proof
 of the earliest time you thought of it.

 _Excerpt._--A part, or an extract of an article.

 _Expert._--One who is trained or is skilful, due to learning and
 practice.

 _Experiment._--(1) To find out an effect, or the cause of it by trials
 and tests. (2) To work out a process for the purpose of developing an
 idea. (3) To show the effect of some previous discovery or invention.

 _Files._--Patents that are arranged systematically for easy reference.

 _Fixture._--See Jig.

 _Free-hand Drawing._--See Drawing, Free-hand.

 _Full paid._--Stock that has been paid for either in cash or by a
 patented invention.

 _High Frequency Oscillations._--(1) Electric oscillations. (2)
 Electric currents which alternate in direction 100,000 or more a
 second.

 _Idea, Raw._--The first idea that comes into the mind as a basis for
 an invention.

 _Improvement._--(1) Adding a new element or part to a composition,
 device or a machine. (2) An improvement constitutes an invention and
 can be patented.

 _Impulse._--A turbine wheel turned by steam forced against its blades.

 _Initiative._--The first step or action.

 _Indicate._--To point out. To show how a thing is done.

 _Inductive Discovery._--(1) The _raw_, or original idea that results
 from the mind process. It precedes _deductive proof_.

 _Inherent stability._--A natural tendency of a body to remain
 balanced, or when upset to right itself.

 _Isometric._--Of equal measure or scale.

 _Isometric Perspective._--Three sets of lines of equal measure, that
 is 120 degrees apart which represent the three dimensions of space.

 _Isometric Cross-section paper._--Paper ruled with lines of equal
 measure for making isometric perspective drawings.

 _Jig._--A tool, or _fixture_ used as a guide for cutting tools where
 duplicate parts are made by a machine.

 _Jobber._--A man who buys in large quantities for the manufacturer and
 sells them to wholesalers or retailers.

 _Key._--A tapering wedge for fastening the collar of a wheel on a part
 of a shaft.

 _Litigation._--Law suits.

 _Low Voltage Currents._--(1) Currents having a pressure up to 500
 volts. (2) Ordinary battery and lighting currents are low voltage.

 _Machine Design._--The scientific designing of machines.

 _Math._--Abbreviation for mathematics.

 _Maxims_, Hiram and Hudson.--Inventors of high explosives, machine
 guns and other things that make for peace in times of war, and make
 for war in times of peace.

 _Mechanical Movement._--(1) The simplest form of a machine. (2) A
 combination of two or more of the mechanical powers.

 _Memorandum._--A written outline of an agreement, or a contract.

 _Micawber._--A character in Dickens’ _David Copperfield_. He was never
 able to get down to anything but was always waiting for something to
 turn up.

 _Model._--(1) An object or a device made to represent an apparatus or
 a machine. (2) A device made to show how an apparatus or a machine
 works. (3) Scale models are smaller than the machines they represent
 and may be built either to show how the finished apparatus will
 appear or they may be actual working models.

 _Monopoly._--The sole right to make, use and sell an invention or the
 product of an invention.

 _Notary Public._--A commissioned official who holds a seal of his
 office and who certifies papers, etc.

 _Oath._--A sworn statement of the truth.

 _Operate._--(1) To put into motion. (2) To do mechanical work. (See
 Actuate.)

 _Ozone._--A colorless gas formed by discharging electricity through
 the air or oxygen.

 _Paper patent._--A patent granted by the patent office for an idea
 that has never been worked out in practice.

 _Part._--A small portion of a device or a machine.

 _Par value._--The full, or face value.

 _Patent attorney._--A lawyer who makes patent law his business or
 ought to.

 _Patent Expert._--One who is specially trained in an art or a science
 which enables him to give expert testimony in patent causes.

 _Patent Office._--(1) The building in which the patent business of the
 government is transacted. (2) The office conducted by the government
 for handling of its patent business. (3) The patent office of the U.
 S. is one of the bureaus of the Department of the Interior and it is
 under the direction of a commissioner of patents.

 _Patent Examiner._--One who examines and passes on patents in the
 patent office.

 _Patentee._--The one to whom a patent is granted.

 _Periphery._--(1) The circumference of a circle. (2) The outer surface
 of a wheel.

 _Perspective Drawing._--See Drawing, Perspective.

 _Perspective, Isometric._--See Isometric Perspective.

 _Philosophy._--(1) The science of all natural laws. (2) The laws,
 causes and principles on which facts can be explained. (See
 Psychology.)

 _Precision._--(1) The state of being very accurate. (2) Said of any
 instrument or machine which works with exactness.

 _Principle._--A truth or cause.

 _Priority._--Being first.

 _Protractor._--An instrument for laying off and measuring angles by
 degrees.

 _Prosecute._--To follow up until a conclusion is reached.

 _Pro Rata._--In proportion.

 _Psychological moment._--The exact time to impress the mind in the
 best way.

 _Psychology._--(1) A branch of philosophy. (2) The science of the mind
 and its operations.

 _Ramifications._--Subdivisions of a subject or branches of a thing.

 _Reaction._--A turbine wheel turned by steam forced from it against
 the air.

 _Rectify._--(1) To make right whatever is wrong. (2) To make a direct
 current of an alternating current.

 _Rectangle._--A four sided plane with right angle corners.

 _Reject._--To refuse to accept, as to reject a claim in a patent.

 _Retainer._--The advance fee paid to an attorney.

 _Retailer._--A man who buys in small quantities and sells piecemeal to
 consumers.

 _Royalty._--A share of the profits paid to the owner of a patented
 article or a device by those whom he allows to make or use it.

 _Scale._--A piece of wood, metal or other material with graduated
 lines on it and used for measuring.

 _Securities._--Property of any kind which has enough value to keep the
 credit good.

 _Semi-circle._--(1) Half of a circle. (2) A segment of a circle equal
 to 180 degrees.

 _Shares._--(1) The equal parts of the capital stock of a company. (2)
 The shares are represented by _certificates_.

 _Shareholder._--An owner of the shares of stock of a company.

 _Shop-right license._--A legal permit given to the owner of a shop to
 make and sell a patented article or device.

 _Sketch._--A crude picture.

 _Standardize._--To make a device or a machine to conform to a certain
 type.

 _Stockholder._--An owner of the shares of the stock in a company.

 _Stock._--(1) The shares of a company which represent its capital.
 (2) Goods traded in for a profit. (3) The raw materials used for
 manufacturing purposes. (4) The manufactured goods that are held in
 reserve.

 _St. Elmo’s Fire._--An electric glow which is often seen at the end of
 a spar of a ship at night.

 _Synthesis._--To combine chemical elements to form a compound.

 _Synthetic._--A chemically prepared substance which is exactly like
 that found in nature, as _synthetic camphor_, _synthetic sapphires_,
 etc.

 _Technical Expert._--See Patent expert.

 _Transfer of Energy._--Changing the energy of one body to another body.

 _Transformation of Energy._--Changing the form of energy, as from
 electricity to magnetism, or from heat to light.

 _Transactions, or Proceedings._--The published reports of scientific
 and other societies.

 _Treasury stock._--The shares that belong to the company and which are
 used to provide it with working capital.

 _Trustees._--About the same thing as _directors_.

 _Tungsten._--A steel gray metallic element.

 _Tyro._--A beginner.

 _Useful art._--Anything which requires ingenuity to fashion, and which
 can be used for some good purpose.

 _Valid._--(1) That which holds good. (2) A patent that is founded on
 fact and in law.

 _Who’s Who._--A red book of noted men and women living in the United
 States.

 _Wholesaler._--One who buys and sells in large quantities.

 _Wing._--The main or supporting plane of an aeroplane.

 _Working Drawing._--See Drawing, Working.




INDEX


  Acetylene gas, 16, 89

  Action of patent office, 125

  Advertising for agents, 167

  Advertising campaign, 173
    How to start an, 179

  Advertising, classified, 169
    Displayed, 177
    Stereotyped copy, 178

  Advertising an inventor’s job, 178

  Advertising patent attorneys, 48, 113

  Advertising versus publicity, 175

  Aeroplane, 43
    Inventing, 215
    State of the art of, 52

  Agent, manufacturer’s, 170

  Agents, advertising for, 167
    Selling through sales, 171

  Agreement, form of an invention, 133

  Air brake, invention of the, 205

  Alternating current generator, 77

  Alloys, some useful, 240

  Aluminum, 16, 89

  Amending the specification and claims, 118, 125

  Ammeter, 83

  Appendices, 229

  Applying for a patent, 117

  Archives of patent office, 126

  Arc lamps, 79

  Assignment, patent, 134, 217

  Atoms and molecules, 61

  Attorneys, advertising patent, 48

  Automobile, invention of the, 209


  Ball bearings, 61

  Band saw, 158

  Battery, 76

  Bell, Alexander, telephone inventor, 206

  Bell telephone, 56, 206

  Bentley and Knight, trolley line inventors, 211

  Berliner, Emile, graphophone inventor, 207

  Bessemer, Henry, inventor of cheap steel process, 204

  Board of examiners-in-chief, 127

  Book,
    of account, 140
    on electro-chemistry, 90
    of mechanical movements, 69
    Minute, 141
    on modern views of electricity, 75
    on Physics, 69
    Stock certificate, 141
    Stock ledger, 142
    Stock transfer, 141
    on Chemistry, 88
    on Wireless, 82

  Bourseul, Charles, telephone inventor, 205

  Branca, steam turbine inventor, 209

  Brokers who advertise, 136

  Brush, dynamo inventor, 46

  Buffing machine, 156

  Bullock, printing press inventor, 203

  Business ability in inventing, 131

  Buying machine tools, 150


  Calcium carbide, 16, 89

  Carborundum, 16, 89

  Carré, Ferdinand, ice machine inventor, 204

  Capital, how to enlist, 135
    Stock, 139
    of a stock company, 138

  Cardboard models, uses of, 42

  Casting in brass and iron, 110

  Castings compared with wood, 237

  Caveats, 217

  Certificate of incorporation, 139

  Chemical apparatus, 87

  Chemicals and their common names, 249

  Chemical compounds, inventing, 14

  Chemical elements and their symbols, 248

  Chemical equipment for experimenting, 86

  Chemical inventions, ideas for, 14

  Chemistry, how to experiment, 84
    First book on, 7
    Inventions in, 59

  Circularizing, 169

  Claims, amending patent, 118, 125
    Patent, 49, 117, 122

  Coal tar colors, 89

  Collins, A. Frederick, wireless telephone inventor, 215

  Commissioner of Patents, 49, 116, 125, 127, 218

  Company, see stock company, 138

  Conferences of associates, 167

  Contracts, about signing, 137

  Copyrights, 221

  Corporation, outfit needed by, 141

  Corporate seal, 142

  Corporation, see stock company, 138

  Correspondent, 47

  Court of Appeals of the District of Columbia, 127

  Cross-sectional drawings, 21

  Current electricity, 74-76


  Daft, Leo, trolley line inventor, 211

  Davenport, Thomas, electric railway inventor, 211

  Davy, safety lamp inventor, 5

  Deductive proof, 6

  De Laval, steam turbine inventor, 209

  Depreciation of machinery, 164

  Design patents, 216

  Diagrams, how to make electrical, 39

  Discoveries, accidental, 4

  Discovery of vulcanized rubber, 4

  Direct current, 76

  Drawing a box, 22

  Drawing, free hand, 19
    Isometric ellipse, 32
    Mechanical, 19

  Drawing paper, isometric, 26
    How to make isometric, 27

  Drawing in perspective, simple way, 26

  Drawing a steam engine, 22

  Drawing tools needed, 29

  Drawings, cross-sectional, 21
    Detailed, 21
    How to letter them, 36
    How to make simple working, 20
    How to shade them, 36
    Isometric, 122
    in perspective, isometric, 20, 25, 26
    Rules for patent, 117
    Scale, 19-21
    Some aids to, 40
    Tools for making simple, 19
    Working, 19

  Drill press, hand, 103
    Pillar type, 153

  Dynamo electric machine, 45

  Dynamo and motor, invention of the, 205


  Eastman, Charles, kodak inventor, 131, 208

  Edison, 5, 46, 131, 180, 206, 207, 210, 213

  Efficiency in manufacture, 147

  Electric,
    Alternating current, 77
    Battery, 88
    Bell, 13
    Block signal system, 58
    Condenser, 75
    Current, 76
    Direct current, 76
    Furnace, 88
    Induction, 75
    Interrupted direct current, 76
    Locomotive, invention of the, 212
    Motors, individual, 157
    Power, 148
    Pulsating direct current, 76
    Railway, invention of the, 211
    Smelting, 89
    Waves, 75

  Electrical,
    Diagrams, how to make, 39
    Equipment for experimenting, 82
    Invention ideas, for, 11
    Symbols, how to make, 36
    Symbols, terms and formulas, 242
    Units, 242

  Electricity, current, 74
    Forms of, 74
    How to experiment with, 74
    Static, 74-75

  Electro-chemical inventions, ideas for, 15

  Electro-chemistry, how to experiment with, 88
    Inventions in, 59, 89

  Electrolysis, 89

  Electromagnet, 13, 78
    Plunger, 79
    Waves, 79

  Electro-mechanical devices, 80

  Electro-mechanical inventions, ideas for, 13

  Electroplating, 88

  Electrotyping, 88

  Electrolytic repairing of copper, 16, 89

  Ellipse, drawing an, 32-34

  Employee’s patent agreement, 99

  Energy, 59

  Energy,
    Forms of, 61
    of motion, 60
    of position, 60

  Ether, 75
    Energy of, 62

  Evidence of conception, 18, 113

  Examiner of interferences, 126

  Examiner, patent office, 50

  Experiment, how to, 58
    With machines, how to, 59
    Working out ideas by, 7
    With electro-chemistry, how to, 88

  Experimenting, value of, 7

  Experts, technical patent, 128


  Faraday, dynamo inventor, 3, 45

  Flying machine, helicopter, 94

  Follow-up letters, 170

  Foreign patents,
    Dominion of Canada, Great Britain, 224
    France and Colonies, Germany and Colonies, Austria and Hungary,
        Belgium, Spain, Italy, Russia, Denmark, 225
    Norway and Sweden, Switzerland, Portugal and Turkey, 226
    Holland, India, Australian Commonwealth, Japan and China, Africa,
        Central America, West Indies, South America, 226

  Fulton, Robert, steamboat inventor, 202

  Ford, Henry, greatest automobile manufacturer in the world, 210

  Free-hand drawing, 19

  Friction, reducing, 236
    Work against, 61

  Finishing your product, 162


  Gas engine, invention of the, 204

  Gas furnace, 150

  Gears and gearing, 238

  Genius versus college professors, 5

  Government monopoly, 112, 127

  Gramme, dynamo inventor, 205

  Graphophone, invention of the, 207

  Grinder, 151

  Gyro-compass, 13, 18

  Gyro-motor for aeroplane, 43


  Hall of Fame, New York University, 203
    Progress and civilization, 203

  Heat, 61

  Helicopter, flying machine, 94

  Hero, steam turbine inventor, 208

  High frequency, Alternators, 78
    Currents, 12, 75
    Machine, 162

  Hiring and firing men, 161

  Hoe Brothers, printing press inventors, 203

  Howe, Elias, sewing machine inventor, 56, 203

  Hydro-electric power, 149


  Ice machine, invention of the, 204

  Idea,
    The big, 181
    Factory, 180
    First raw, 3, 6
    Getting an, 1
    How to get an, 1
    of an inventive genius, 2
    Protecting your, 97
    What it is, 2
    Where it originates, 3

  Ideas,
    For chemical inventions, 14
    For electrical inventions, 11
    For electro-chemical inventions, 15
    For electro-mechanical inventions, 13
    For inventions in general, 9
    Kinds of, 3
    For mechanical inventions, 9
    Protecting raw ideas, 16
    Thought out, 6
    Working out on paper, 19

  Incandescent light, invention of the, 210

  Inclined plane, 63

  Index of the patent office, 53

  Individual electric motors, 157

  Induction coil, 76

  Inductive discovery, 3

  Infra-red waves, 75, 79

  Infringement suit, 18

  Infringers of patents, 127

  Initial funds, how to raise, 132

  Interferences, 126

  Interruptor, 76

  Improvements needed, 181

  Iron ore, reduction of, 90

  Invent,
    What to, 180
    What not to, 197

  Inventing,
    Chemical compounds, 14
    Secret of, 180
    As a vocation, 131

  Invention,
    Agreement, form of an, 133
    Guardian angel of, 7
    Heroes of, 200
    How to patent your, 112
    Keeping an interest in, 133
    Manufacturing an, 146
    Pay, making your, 131
    Protecting your, 97, 119
    Record of your, 18
    Of the sewing machine, 56
    Of the wardrobe trunk, 4
    What it consists of, 118

  Inventions,
    In chemistry, 59
    In electro-chemistry, 59, 89
    In general, ideas for, 9
    Great, and what they paid, 203
    That have paid big, little, 201
    Ideas for chemical, 14
    Ideas for electrical, 11
    Ideas for electro-chemical, 15
    Ideas for electro-mechanical, 13
    Ideas for mechanical, 9
    Some big, needed,
      Safety first, automobiles, 187
      Aviation, 188
      Chemistry, 190
      Electricity, 191
      Electro-chemistry, 192
      Building, mining and metallurgy, 193
      Printing, moving pictures, 195
      Other field of endeavor, 196
    Needed,
      For the farm, some little, 183
      For fun, 185
      For the house, 182
      For the office, 184
      For the person, 182
    Protection against theft, 100
    Real, and what they paid, 202
    Selling small, 167
    Simple, and what they paid, 202
    What some have paid, 200

  Inventive ability, 131

  Inventive world, tour of, 200

  Inventors, 5
    Self-taught, 5

  Inventor’s salary contract, 144

  Isometric,
    Drawing paper, 26
    Ellipse, how to draw, 32
    Paper, how to make, 27
    Perspective drawings, 20, 26, 122


  Jig saw, 157


  Kinetograph, invention of the, 213

  Kinetoscope, invention of the, 213

  Kodak camera, invention of the, 208


  Lathe, engine, 152
    Foot power, screw cutting, 103
    Plain, 151
    Screw cutting, power, 152

  Lawyer, retaining a, 144

  Lever, 63
    Bent, 64
    Compound, 64-65

  Leyden jar, 75

  Light waves, 75

  Light, 79

  Linotype, invention of the, 212

  Lists of consumers, where to buy, 169

  Locomotive, invention of the, 202

  Lodge, Sir Oliver, 181


  Machine design, 58

  Machine screws and nuts, sizes of, 235

  Machine tools, buying, 150

  Machines, commercial uses of, 62
    Compound, 69
    How to experiment with, 59
    Principles of, 62

  Magnet, electro-, 78
    Permanent steel, 78

  Magnetism, 74, 78

  Magneto-electric machine, 76

  Mail order business, 168

  Marconi, William, wireless telegraph inventor, 6, 214

  Manikin for drawing, 40

  Marketing your product, 166

  Mathematical formulas, some useful, 231

  Manual of classification, patent office, 57

  Manufacture, problem of, 146

  Manufactured product, finished, 162

  Manufacturer’s agent, 170

  Manufactory, locating a, 149
    Starting your own, 148

  Manufacturing your invention, 146

  Material, buying the raw, 159

  Materials, automatic machine made, 107, 159
    Buying, 108
    Raw, 149

  Mechanics, principles of, 58

  Mechanical,
    Drawings, 19
    Inventions, ideas for, 9
    Movements, 58, 69, 70, 71, 72, 73
    Powers, 59, 63

  Mergenthaler, Ottmar, 212

  Micrometer, 103
    How to read a, 105

  Metric,
    Changed to English measure, 234
    or decimal system, 232
    Measures of length, 233
    Measures of weight, 233

  Milling machine, universal, 156

  Minute book, 140

  Model,
    of a British express locomotive, 95
    Building a, 96
    How to make, 91
    Makers, 97
    Ways to make, 97

  Models,
    How to make cardboard, 42
    in Patent Office, 91
    Rough, 91-92
    Scale, 91-92, 95
    Working, 91-92

  Molecules and atoms, 61

  Monopoly, Government, 112, 127

  Morse, Samuel F. B., telegraph inventor, 203

  Moving pictures, invention of the, 212

  Muybridge, Eadweard, 213


  Nitric acid of the air, 16, 89


  Oath, patent, 120
    Form of, 124

  Official Gazette of the Patent Office, 53, 218

  Ohm’s Law, 243

  Organizing a shop force, 160

  Oscillating current, 78

  Otto, N. A., gas engine inventor, 204

  Overhead charges, 164
    How to figure, 165

  Oxy-Hydrogen furnace, 85

  Ozone of the air, 89


  Page, C. T., electric railway inventor, 211

  Parsons, steam turbine inventor, 209

  Partner, how to secure, 135-136

  Partnership, forming a, 135

  Patent,
    About an interest in a, 134
    Agreement, Employee’s, 99
    Amending claims, 125
    Application, 116
    Application, filing fee for, 114
    Applying for a, 117
    Applying for your own, 115
    Assignment, 134
    Causes, 128
    Claims, 49, 117, 120, 122
    Claims, Amending, 117
    Claims, narrow, 113
    Copy of a, 125
    Counsel, 128
    Design, 216
    Drawings, 120, 122
    Drawings, rules for, 117
    Final Government fee for, 114
    Getting a, 51
    is granted, after your, 127
    is granted, when your, 127
    Interferences, 55, 126
    that pended for seven years, 126
    is pending, while your, 125
    Petition, 120
    Specifications, 49, 53, 117, 120, 122
    Suits, 128
    System bubbles, 115
    What it consists of, 112, 120
    What you may, 118

  Patentee, 127

  Patenting your invention, 112

  Patent attorneys,
    Catching your, 115
    Flat-rate fee for, 114
    Judgment of, 118
    Retaining a, 47
    Temptation of, 115

  Patent attorneys, 54, 126, 127
    Advertising, 48, 113
    Choosing a, 112
    High-grade, 114
    Least charges of, 224
    Watching, 117

  Patent examiner, 50, 91, 114, 115
    Versus inventors discontent, 126
    and sewing machine needle, 56
    Sub-cellar, 51
    Methods, 125

  Patent experts, technical, 128

  Patent oath, 120, 124

  Patent office,
    Action, 125
    Archives, 126
    Citing references, 117
    Citations, 125
    Fees, 217
    Index, 53
    Manual of classification, 57
    Official Gazette, 53
    Red tape, 126
    Rejection of claims, 117
    Rules of practice of, 116

  Patent office search, a desk, 48
    a free, 48
    a special, 48
    Preliminary, 49

  Patents,
    Foreign, 224
      See foreign patents
    Paper, 130
    Number granted each year, 118

  Patterns, complicated, 110
    Making, 108

  Perpetual motion, 62, 77, 199

  Perspective drawings, 25
    Isometric, 20, 26

  Perspective, simple way to draw in, 26

  Petition, patent, 120

  Philosophy, 3, 6

  Phonograph, invention of the, 207

  Physics, first book on, 7

  Planer, 154

  Planté, Gaston, storage battery inventor, 208

  Power, 59, 65

  Protractor, how to use it, 31

  Protecting raw ideas, 16

  Preliminary search, 47

  Printing press, perfecting, invention of the, 203

  Priority, 16

  Profits, how to figure, 165

  Promoter, ordinary, 137
    Professional, 100
    Real, 137
    Tin-horn, 137
    Where he comes in, 136

  Pseudotriakis microdon, 113

  Publicity, how to get it, 175

  Pulley, 63


  Radiation, 74, 79

  Reading helps, 6

  References, Patent Office citing, 117

  Register of copyrights, 221

  Reis, Johanne Phillip, telephone inventor, 205

  Resistance bridge, 83

  Rights, selling invention, 135

  Ro, a universal language, 50

  Roosevelt, 115

  Royalties on inventions, 135

  Rubber, discovery of, 4

  Rules of practice, 120, 135, 218


  Saving the watchword, 194

  Scale drawings, 19, 21

  Screw, 63
    Theory of the, 68

  Seal, corporate, 142

  Seal Press, 142

  Search, a desk patent office, 48
    Free patent, 48, 113
    Preliminary Patent Office, 49
    Special Patent Office, 49

  Selden, George B., daddy of the automobile, 209

  Selling direct to the consumer, 172

  Selling goods, basic principles of, 166

  Selling through sales agents, 171

  Selling the stock issue of a company, 147

  Selling through the trade, 174

  Sewing machine, invention of the, 203

  Sewing machine needle, 56

  Shaper, 155

  Shop force, organizing a, 160

  Shop foreman, hiring a, 160

  Shop rights, selling, 135

  Shop, starting your own, 148

  Shrinkage of castings, 111

  Siemens, dynamo inventor, 204

  Snap-shot camera, invention of the, 208

  Solders, hard, 241

  Solenoid, 13, 79

  Spark-coil, 76

  Specifications, patent, 53

  Starr, J. W., incandescent lamp inventor, 210

  Standardizing your product, 159

  Static electricity, 74-75

  Specification, amending the, 118
    Patent, 49, 117

  State of the art, 45
    Having a patent attorney look it up, 47
    How to learn the, 46
    How to look it up, 47, 51
    Use of the, 46
    What it means, 45

  Steam boat, invention of the, 202

  Steam engine, drawing of a, 22
    Invention of the, 202

  Steam turbine, invention of the, 208

  Steel, high speed, 244

  Steel process, invention of the, 204

  Stephenson, locomotive inventor, 202

  Stock certificate, 141

  Stock certificate book, 141

  Stock company, fees for incorporating, 140
    How it is operated, 142
    How to organize a, 139

  Stock ledger, 142

  Stock full paid, 143

  Stock room, 161

  Stock of a company, selling the, 144

  Stock transfer book, 11

  Stock, treasury, 143

  Stock company, what it is, 138

  Storage battery, invention of the, 208

  Supreme Court, U. S., 112

  Symbols, how to make electrical, 36

  Synthetic gems, 85


  Taps and dies, sizes of, 235

  Telautograph, 13, 17

  Telegraph, invention of the, 203

  Telegraph sounder, 13

  Telephone, Bell, 56
    Invention of the, 205

  Telephone transmitter, 76

  Territorial rights, 135

  Tesla, dynamo inventor, 46

  Thermometer scales, four chief, 251

  Things are money, 201

  Thompson, dynamo inventor, 46

  Thoughts are things, 201

  Thurber, Charles, typewriter inventor, 207

  Time stamp, Thompson, 161

  Tools, useful jewelers and machinists, 101

  Tour of the inventive world, 200

  Trade marks, 220

  Transfer tax law, 141

  Treasury stocks, 143

  Trolley car and line invention of the, 211

  Twining, ice machine inventor, 204

  Twist drills, sizes of, 235

  Typewriter, invention of the, 207


  Ultra violet waves, 75, 79

  United States patent, 127

  United States Patent Office, 47, 135

  United States Supreme Court, 112

  Unit of work, 60

  Universal milling machine, 156


  Van Depoele, C. J., trolley line inventor, 211

  Velocity, 60

  Vernier, 103

  Vernier, how to read a, 103

  Violet ray machine, 162

  Vibrator, 76

  Voltmeter, 83


  Watt, James, steam engine inventor, 202

  Wedge, 63

  What not to invent, 197

  Wheatstone, Charles, telephone inventor, 206

  Wheel and axle, 63

  Weston, dynamo inventor, 46

  Westinghouse, air brake inventor, 131, 205

  Wilde, dynamo inventor, 204

  Winding machine, 83

  Wire
    Gage, how to use a, 106
    Number, length, weight and resistance of pure copper, 244, 245
    Prices of insulated magnet, 247
    Number of turns that can be wound in a given space, 246

  Wiring diagrams, how to make, 39

  Wireless telegraph, invention of the, 214

  Wireless telephone, 12

  Wireless telephone, invention of the, 215

  Wireless waves, 75

  Words and terms used in this book, 253

  Work, 59
    Energy and power, 60
    Farming it out, 147
    Unit of, 60

  Working drawings, 19

  Wright brothers, aeroplane inventors, 215




FOOTNOTES


[1] Ro is a universal language invented by the Rev. Edward P. Foster of
Marietta, Ohio. According to the _New York Times_ the frogs have talked
_ro_ from the first and any child ought to be able to learn it in less
than twice the lifetime of Old Parr.

[2] For a further explanation of these very interesting phenomena, read
_Modern Views of Electricity_, by Sir Oliver Lodge.

[3] The _pseudotriakis microdon_ is one of the rarest species of
sharks. It is a small toothed nurse shark and is known from only two
specimens, one of which turned up on the coast of Portugal and the
other on Long Island.

[4] “Fear God and take your own part,”--_Roosevelt._

[5] See Chapter XII on Design Patents.

[6] The italics are not mine.


       *       *       *       *       *

Transcriber’s Notes:

Italic text is denoted by _underscores_ and bold text by ~tildes~.

“[F]” and “[R]” were used to represent blackletter in the table of
Appendix O.

The half-title page has been removed.

Variations in spelling, hyphenation, and accents remain as in the
original unless noted below.


  Page 34, “AB” changed to “A B” (“as shown at A B”).
  Page 140, “incoporation” changed to “incorporation” (“the subscribers
    to the certificate of incorporation”).
  Page 140, period changed to semicolon after “the amount of cash must
    be stated.”
  Page 144, comma added after “(a) by personal solicitation.”
  Page 178, “sensative” changed to “sensitive” (“and impress the
    sensitive area of his brain”).
  Page 182, period added after “Fig” (“see Fig. 103”).
  Page 203, “webb” changed to “web” (“The first web printing press”).
  Page 233, “1000” changed to “1,000.”
  Page 234, “1,6093” changed to “1.6093.”
  Page 248, “Florine” changed to “Fluorine.”
  Page 253, “operate” changed to “Operate” (“See Operate”).
  Page 261, period changed to comma after “of mechanical movements.”
  Page 263, “Ellipose” changed to “Ellipse.”
  Page 264, “individual” changed to “Individual” (“Individual electric
    motors”).
  Page 266, comma added after “Metric.”
  Page 266, comma added after “Model.”
  Page 266, comma added after “Models.”
  Page 267, comma added after “Partnership.”
  Page 267, comma added after “Patent.”
  Page 267, comma added after “Patents.”
  Page 268, superfluous comma removed in “Pseudotriakis microdon.”








End of Project Gutenberg's Inventing for Boys, by A. Frederick Collins