ELECTROLYSIS.
Liquid which will conduct a current of electricity is called an
*electrolyte*. All electrolytes are compounds, that is, they consist of
more than one substance. When an electric current passes through a
liquid it decomposes it. This process of decomposition is called
*electrolysis*.
Pure water is not a conductor of electricity. If sulphuric acid is added
to water, the mixture become an electrolyte and will conduct. If an
electric current is passed through water containing sulphuric acid, it
will decompose the water.
[Illustration: FIG. 185.—Apparatus for Electrolysis Experiment.]
Water is composed of oxygen and hydrogen and so bubbles of oxygen and
hydrogen gas will rise from the liquid.
Figure 185 illustrates a very simple arrangement for decomposing
acidulated water into oxygen and hydrogen gases.
It consists of a bottle with the bottom broken out, and provided with a
cork fitted snugly into the neck. Two glass tubes pass through the cork.
A small piece of platinum wire is sealed into the inside end of each
glass tube. The platinum wires are connected to copper wires leading out
of the lower ends of the tubes.
If the bottle is inverted and filled with a dilute solution of sulphuric
acid, the current from two or three dry cells will decompose the water.
The battery should be connected to the wires running through the glass
tubes.
Bubbles of gas will rise from the platinum wires. Oxygen gas will rise
from the positive wire or electrode and hydrogen gas from the negative
electrode.
If two test tubes are filled with acidulated water and then inverted
over the wires, the tubes will collect the gas. In a few minutes it will
be noticed twice as much hydrogen as oxygen has been generated.
If copper or brass electrodes &re used the acid will attack the positive
one and a chemical action will take place which will prevent the
liberation of any appreciable amount of oxygen, unless an excessive
amount of current is passed through.
ELECTROPLATING.
Electroplating consists of coating bodies with metal by means of an
electric current.
The proper chemicals, a small tank and a suitable source of current are
the only apparatus required. The process may be outlined as follows:
Thoroughly clean the article to be electroplated so as to remove all
grease and dirt. Attach it to the negative pole of the battery and
suspend it in an electrolyte composed of some chemical salt of the metal
to be deposited. In order to maintain the strength of the solution, a
piece of metal of the kind to be deposited is attached to the positive
electrode.
A tank for plating small articles such as keys, rings, knives, etc., may
be made out of a square glass battery jar by providing it with a wooden
moulding fitted around the top edge to support the conductor rods. The
rods are made of brass or copper and are threaded at one end so as to be
provided with binding posts. The centre rod is the one from which the
articles to be plated are suspended. They should be attached to it by
means of a thin copper wire. The two outside rods support the anodes.
The anodes are sheets of metal of the kind to be deposited which, in the
case of copper plating, would be copper, in a case of silver plating
silver, nickel for nickel plating, etc.
[Illustration: FIG. 186.—Electroplating Tank.]
Objects which are to be plated must be free from all traces of dirt or
grease or the plating will not be uniform because it will not stick to
the dirty spots.
Articles made of plaster, wax, etc., which are not conductors of
electricity can be plated by first covering with powdered graphite.
Articles of iron, steel, zinc and tin cannot be silver or gold plated
unless first covered with a thin coating of copper.
A single storage cell is an excellent source of current for
electroplating. A rheostat should be placed in the circuit so that the
current can be regulated. The negative pole should be connected to the
centre rod from which the articles are suspended. The positive pole is
connected to the rods supporting the anodes.
The tank should be filled with electrolyte to within about an inch of
the top. The articles to be plated and also the anodes should be
completely submerged.
The electrolyte used for copper plating is simply a solution of copper
sulphate in water. The electrolyte for nickel plating is composed of one
part of nickel sulphate dissolved in twenty parts of water to which one
part of sodium bisulphate is added.
Articles which have been electroplated must be buffed to give them a
bright polish.
ELECTRIC CURRENT GENERATED BY HEAT.
If the point of contact between two dissimilar metals is heated, a
current of electricity will be generated.
This principle was discovered nearly one hundred years ago by a
scientist named Seebeck, and has resulted in many attempts on the part
of inventors to utilize the heat of the sun’s rays in producing
electricity.
[Illustration: FIG. 187.—Generating Electric Current by Heat.]
An interesting experiment illustrating the production of electricity by
heat can be easily performed with very simple apparatus. An alcohol
lamp, candle or source of heat, a piece of copper, a steel needle and a
galvanometer or a telephone receiver are all that are necessary.
The galvanometer or the telephone receiver, whichever is used, is for
the purpose of detecting the electric current.
Connect the needle and the piece of copper, which should preferably be a
small sheet, to the galvanometer or telephone receiver. Hold the copper
sheet over the flame of the alcohol lamp until it is quite hot and then
touch the hottest portion with the point of the needle. Enough current
will be generated to produce a click In the telephone receiver or to
cause the galvanometer needle to move. The needle should be pressed
against the copper tightly enough so that the point cuts through the
scale or oxide on the surface and makes a good electrical contact with
the metal underneath.
Various devices for the production of electricity consisting of a large
number of strips of dissimilar metals in contact with one another and
arranged so that they can be easily heated have been invented. They are
called "thermopiles."
A HANDY LIGHT.
Figure 188 shows a simple and handy form of light which utilizes the
current from a home made primary cell. It consists of a glass fruit jar,
fitted with a tight wooden top. A miniature porcelain socket and a 1.5
volt tungsten lamp are mounted on top.
The battery is arranged so that the zinc element can be drawn up out of
the solution when the light is not in use and any waste thereby
prevented. The zinc electrode consists of a strip of that metal fastened
onto the lower end of a brass rod by means of two threaded nuts. The
upper end of the rod passes through a small metal collar on the top of
the cover, provided with a thumb-screw so that when the electrode is
lifted up out of the solution it may be clamped firmly in that position.
The zinc strip should not be so long that it will not clear the solution
when raised up if the jar is about half filled.
[Illustration: FIG. 188.—A Handy Light.]
The positive electrode is a battery carbon mounted on the lower end of a
brass rod. The brass rod in this case is not movable because the carbon
can remain in the solution indefinitely without any waste.
The joint between the brass rods and the electrode should be coated with
paraffine so that the chemicals in the solution will not cause any
corrosion. The rods should be connected to the lamp socket. When the
zinc is lowered into the solution, the lamp will be lighted by the
current generated.
The electrolyte should be that described as the "bichromate" solution on
page 34 of Vol. I of this book.
AN EXPERIMENTAL ARC LAMP.
An arc lamp is operated by causing an electric current to pass between
two carbon rods. If the voltage is high enough, carbon vapor will form
between the rods when they are separated a short distance. It requires
an E. M. F. of approximately fifty volts to produce and maintain an arc.
A six volt storage battery will heat a pair of sharp pointed carbons to
incandescence and produce a light somewhat similar to the electric arc.
[Illustration: FIG. 189.—Experimental Arc Lamp.]
Ordinary carbon rods such as those used in flashlight batteries will
serve very nicely for a "battery arc lamp." The ends should be filed to
sharp points. Figure 189 shows a simple method of mounting the carbons.
The lower one is soldered to a piece of brass strip by taking advantage
of the brass cap pressed over the upper end of flashlight battery
carbons.
The upper carbon is mounted on the forward end of a brass lever which is
pivoted near the back end so that an adjustable counterweight may be
used to regulate the pressure on the point of contact between the two
carbons.
If the carbons are touching lightly and are connected to a strong
battery of six volts or more, the point of contact will be heated to
incandescence and will produce a dazzling white light.
A real arc lamp for operation on the 110 volt current, in series with a
bank of lamps, may be constructed on this same scheme by using larger
carbons and eliminating the counterweight. The upper arm should be
pivoted in the same manner but should move stiffly so that it will
remain in any position in which it is set.
If the 110 volt current is used, the carbons should be brought together
and then separated a short distance. The current will continue to flow
across and will form an arc producing a very powerful purplish white
light. The arc will consume the carbons quite rapidly and also generate
a great deal of heat. Therefore if it is intended to use the light for
any length of time it is advisable to fasten the carbons by means of a
clamp so that they may be easily replaced.
A MAGNETIC DIVER.
This is a mystifying piece of apparatus to those who do not know its
secret. The little diver apparently travels up and down from the bottom
of a jar full of water to the surface at a word of command.
The diver consists of a small glass test tube about two inches long
having the figure of a man painted upon it. The lower end is closed by a
very small cork through which is pushed a large iron tack with the head
on the outside. The test tube contains just enough water to float head
up even with the surface of the water. The exact amount of water
required to just permit enough buoyancy for the diver to rise again to
the surface after he has been to the top will have to be determined by
careful experiment.
The jar containing the diver should be set on a table having a drawer in
which a pair of powerful electromagnets can be placed directly under the
jar. The electro-magnets are connected to a strong battery and a switch
located under the rug or carpet and so arranged that it may be closed by
stepping on it lightly and without attracting attention. If the diver
does not have too much bouyancy the attraction between the tack and the
electro-magnets when the switch is closed should be sufficient to cause
him to descend to the bottom of the jar. When the current is turned off
the diver should rise again.
[Illustration: FIG. 190.—The Magnetic Diver.]
THE MAGNETIC FISH.
The same sort of a scheme employed in the Magnetic Diver may be used for
producing a magnetic fish which will swim around and around a pan of
water.
[Illustration: FIG. 191.—The Magnetic Fish.]
It consists of a small wooden fish having a magnetised sewing needle
attached to the under side. The fish is placed in a bowl of water on a
table having a drawer in which a pair of electro-magnets mounted on a
rotating wooden arm may be placed so that they swing around directly
underneath. A piece of strong twine wrapped around an empty spool and
attached to the centre of the arm makes it possible to rotate the
magnets by pulling on the string. When the magnets are connected to a
battery they will exert a strong magnetic pull upon the needle fastened
to the fish and if slowly rotated will cause the latter to follow slowly
around the bowl.
A MAGNETIC CLOWN.
Small figures of men or animals cut out of sheet iron will perform many
amusing acrobatic feats when under the influence of a magnet.
[Illustration: FIG. 192.—The Magnetic Clown.]
Such figures are easily cut out of an old tin cracker box with a pair of
snips or strong shears. A realistic appearance may be secured with the
aid of a little paint.
A tin clown having a sharply pointed hat, hands and feet will do all
sorts of stunts when hanging from the poles of a horseshoe magnet. If
several clowns are made they can be caused to hold hands, stand on each
others heads, jump up in the air, etc.
AN ELECTRIC BREEZE.
If a sewing needle is connected to one of the discharge rods of a static
machine and the point of the needle is presented to the flame of the
candle while the machine is in operation, the flame will be repelled
just as if a breeze or current of air were issuing from the needle. This
is caused by the "brush" discharge which takes place whenever high
voltage electricity has a chance to escape from a sharp point or edge.
The brush discharge will be much more marked if the condensers or Leyden
Jars are not connected to the discharge rods. The "electric breeze" can
be felt if the point of the needle is brought near to the side of the
face. It is necessary that the needle and the wire connecting it to the
static machine be very carefully insulated from all surrounding objects
which might dissipate the electricity before it has an opportunity to
escape from the needle point.
[Illustration: FIG. 193.—An Electric Breeze.]
A STATIC MOTOR.
This is a motor operated by the electricity from a static machine. It
does not possess any appreciable amount of power and must be very
carefully built and balanced in order to operate.
It consists of four celluloid "ping-pong" balls, B, B, B, B, covered
with tinfoil and mounted on opposite ends of two wooden spokes. The
balls should be at right angles to each other as shown in the
illustration. The spokes pass through a cork. The cork is mounted on a
wire spoke or knitting needle passing through its centre and supported
in small notches in the top of two upright wooden bearings. The device
must be very carefully balanced so that the slightest impulse will cause
it to spin and so that there will not be any dead centre.
The upright bearings are mounted on a wooden base. Two other tinfoil
covered balls A, A, are supported on glass or rubber insulating rods at
opposite ends of the base on a level with the axle and in such a
position that the balls B, B, B, B, almost touch A and A as they swing
past.
[Illustration: FIG. 194.—The Static Motor.]
Connect A and A each to one discharger rod on the Wimshurst machine.
Start the machine and give the axle of the static motor a twist. As the
balls B, B go past A and A they will receive a charge of electricity
which will cause them to repel each other until they have swung past the
other ball on the opposite side and discharge their electricity in
return for a charge of the opposite sign.
Any of the Following
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COLE & MORGAN
Publishers of the Arts and Sciences Series
P.O. Box 473 New York, N. Y.
*The Boy Electrician*
Practical Plans for Electrical Toys and Apparatus, with an Explanation
of the Principles of Everyday Electricity.
*By ALFRED P. MORGAN.*
Author of "Wireless Telegraph Construction for Amateurs" and "Wireless
Telegraphy and Telephony," etc.
*With full-page Illustrations and 324 Working Drawings and Diagrams*
*by the author. 8vo., Cloth, Net Price, $2.00.*
This is the age of electricity. The most fascinating of all books for a
boy must therefore be one dealing with the mystery of this ancient force
and modern wonder, even a mere list of whose services is impossible. The
best qualified of experts to instruct boys, Alfred P. Morgan, has in a
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kinds of motors, telegraphs, telephones, batteries, etc., and to do so
economically, but has explained the principles upon which these depend
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well presented and so attractive is this really great book that it will
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over the pages of this book, one cannot but be impressed by the
excellent illustrations, clearness of expression and the large number of
subjects that are covered. It is beyond doubt the best book in this line
that has ever been written or published. It is a book that will delight
every boy who has a leaning towards electrical experiments. The author
writes in a clear and chatty style and while he has a thorough technical
knowledge of his subject he has succeeded in treating it in a simple
manner so that it is readily intelligible to his young readers.
*Among the Chapter Headings and Contents are:*
Magnets and Magnetism—Static Electricity—Static Electric Machines—Cells
and Batteries—Electro-Magnetism and Magnetic Induction—Electrical
Units—Electrical Appurtenances—Electrical Measuring Instruments—Bells,
Alarms and Annunciators—Electric Telegraphs—Microphones and
Telephones—Induction Coils—Transformers—Wireless Telegraphy—Wireless
Telephony—Electric Motors—Dynamos—An Electric Railway—Miniature
Lighting—Miscellaneous Electrical Apparatus.
*READ WHAT HAS BEEN SAID OF IT.*
"Even a casual glance through the many pages of the book does not fail
to emphasize the fact that Mr. Alfred P. Morgan has indeed succeeded
well in giving the juvenile electricians a work that has long been
sought."—Popular Electricity.
"We have no hesitation in commending the book to the attention of the
juvenile audience for which it is intended."—Boston Post.
"A great book for enterprising boys. Bright boys will highly appreciate
it and feel like thanking the wideawake publishers for putting such a
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"In this age of electricity a book like the present one is both
fascinating and valuable especially to boys. The book is attractive with
its many illustrations and will prove of much educational value for any
bright boy."—Zion’s Herald.
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fall under the spell of tinkering with electrical apparatus."—Boston
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*Experimental Wireless Construction*
*EIGHTY-SIX PAGES NINETY-THREE ILLUSTRATIONS*
*Only 25 Cents, Postpaid*
Here at last is the book which every young experimenter interested in
constructing his own wireless apparatus has been looking for.
A book which tells how to build apparatus which anyone would be proud to
own. It is a more advanced book than "Wireless Construction and
Installation for Beginners," and describes apparatus which is much more
elaborate and sensitive. The instruments have all been the subject of
considerable experimental work and study. All the apparatus has been put
to practical test and carefully improved by clever experts. By
purchasing this book you get the benefit of vast knowledge and
experience and are enabled to build far better instruments than by
following your own designs and haphazard methods.
THE TREMENDOUS POPULARITY OF THIS VALUABLE LITTLE BOOK IS ONLY AN
INDICATION OF ITS GREAT WORTH.
It has only been on the market a short time, yet the sales will
undoubtedly soon reach a point which would indicate that experimenters
unquestionably consider, that in proportion to its size, it is the best
book on the market.
It does not describe any old or obsolete forms of wireless apparatus but
only the latest types of aerials, spark coils, keys, gaps, condensers,
helixes, oscillation transformers, loose couplers, tuning coils,
detectors, loading coils, variable condensers, aerial switches, etc.
IT IS ONE OF THE MOST DETAILED AND THOROUGH BOOKS EVER PUBLISHED.
The information is all intensely practical. Complete directions and
dimensions are given. Nothing is left to be guessed at. The book must
really be seen to be appreciated.
*Partial Contents*
Chapter I.—THE AERIAL. The Location of the Station. The Construction of
an Operating Bench. The Aerial and Ground. The Supports or Masts. Types
of Aerials. How to Erect an Aerial. Protection from Lightning, Etc.
Chapter II.—SPARK COILS. The Construction of Spark Coils. A 1/4-inch
Spark Coil. A 1/2-inch Spark Coil. A 1-inch Spark Coil. A 1 1/2-inch
Coil. A 2-inch Coil. Sources of Current. Dry Cells. Storage Cells.
Wireless Keys, Etc.
Chapter III.—TRANSMITTING APPARATUS AND ITS CONSTRUCTION. Step-down
Transformers. Spark Gaps. The Oscillation Condenser. Leyden Jars.
Helixes. Oscillation Transformers, Etc.
Chapter IV.—THE RECEIVING APPARATUS AND ITS CONSTRUCTION. A Silicon
Detector. A Galena Detector. The Double Slide Tuning Coil. How to Make a
Fixed Condenser. Building a Loose Coupler. The Loading Coil. How to Make
a Variable Condenser, Etc.
Chapter V.—ARRANGEMENT AND OPERATION OF THE APPARATUS. Aerial Switches.
The Buzzer Test. Using More Than One Detector. Shunting the Detector.
Complete Outfits. Portable Sets. The Operation of the Station, Etc.
*LESSONS IN WIRELESS TELEGRAPHY*
FOURTH EDITION
72 Pages 66 Illustrations
A systematic course in the elementary principles. Written so you can
understand it. In 35 lessons.
1.—Magnetism. 2.—Magnetic Induction. 3.—Primary and Secondary Cells.
4.—Electric Currents. 5.—Electromagnetism. 6.—Dynamo-Electric Machinery.
7.—The Induction Coil. 8.—The Transformer. 9.—Leyden Jars and
Condensers. 10.—Electromagnetic Theory. 11.—Electric Waves.
12.—Principles of Wave Telegraphy. 13.—The Aerial. 14.—The Wireless
Coil. 15.—The High Potential Transformer. 16.—The Oscillation Condenser.
17.—The Helix. 18.—Spark Gaps. 19.—The Key. 20.—Aerial Switches.
21.—Anchor Gaps. 22.—Detectors. 23.—Tuning Coils. 24.—Loose Couplers.
25.—Fixed Condensers. 26.—Variable Condensers. 27.—Telephone Receivers.
28.—Hot Wire Ammeter. 29.—Potentiometer. 30.—Dead End Losses and
Switches. 31.—Distributed Capacity. 32.—Poulsen Arc. 33.—Receiving
Undamped Waves. 34.—The Audion Amplifier. 35.—Hook-Ups.
*Price, 25 Cents, Postpaid*
If you want to understand your apparatus and how it works, you will need
this book—over 15,000 copies in use.
*Price, 25 Cents, Postpaid*
*Model Flying Machines*
*HOW TO BUILD AND FLY THEM*
Will prove interesting and valuable.
Have you ever built and flown a Model Racer?
If not, you have missed something.
Price, 25 Cents, Postpaid.
Model Aeroplaning is one of the most fascinating and instructive of
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Thousands of young men and boys have formed Model Aero Clubs and
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"MODEL FLYING MACHINES" of the _Arts and Sciences_ series is the only
book giving reliable data and instructions for the construction of
practical Model Aeroplanes.
IF YOU ARE A BEGINNER, this is the book that you ought to have. It will
start you right. It tells how to build seven different types of
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several Long Distance Racing Models.
IF YOU ARE INTERESTED IN MODEL AEROPLANING, this book will prove the one
you have been looking for. Gives valuable "Kinks". Tells how to carve
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*Wireless Construction and Installation for Beginners*
SEVENTY-THREE PAGES SIXTY-SEVEN ILLUSTRATIONS.
(Second Edition.)
A Practical Handbook giving detailed instructions for the Construction
and Operation of a Boy’s Wireless Outfit.
*Only 25c. Prepaid*
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shows how to build the various instruments but describes their actual
workings and tells how to operate them.
*EVERY BOY IS ADVISED TO*
*SEND FOR A COPY*
Written in a very clear and simple style, the book is invaluable to a
beginner. He will be able with its aid to construct simple apparatus of
the latest and approved type. The instruments described in the book have
been the subject of considerable experimental work and special study.
They are modeled along simple lines so that they will be easy and
inexpensive to construct, but at the same time combine features which
make them very sensitive and capable of receiving or transmitting
messages greater distances than some more complicated apparatus.
*THIS BOOK, CONSIDERING ITS WORTH, IS A GIFT AT 25c.*
There are no old or obsolete forms of wireless apparatus discussed, but
only the latest types of tuning coils, receiving transformers, fixed
condensers, keys, spark coils, detectors, etc. The book is illustrated
by numerous detailed working drawings giving all dimensions. Several
full-page views of the apparatus enable the beginner to fully comprehend
the text.
*THE MOST THOROUGH AND COMPLETE ELEMENTARY WIRELESS*
*CONSTRUCTION BOOK PUBLISHED*
The pages on the construction and installation of aerials will be found
to be of considerable help to the experimenter, for it is here that the
most trouble is experienced by the beginner. The practical and helpful
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book.
*PARTIAL CONTENTS*
Chapter I.—*WIRELESS TELEGRAPHY*. An intensely interesting subject;
amateur wireless telegraphy; the purpose of the aerial and ground; the
apparatus used to send messages; the apparatus used to receive messages.
Chapter II.—*AERIALS AND GROUNDS*. Where to put up the aerial; types of
aerials; the "T" aerial; the masts; the wire; insulators; leading in the
wires; the ground.
Chapter III.—*HOW TO BUILD AND OPERATE THE SIMPLEX DOUBLE SLIDE
RECEIVING OUTFIT*. The tuning coil; the tube; the sliders; the fixed
condenser; the detector parts; assembling the set; connecting the
instruments; operation.
Chapter IV.—*HOW TO BUILD THE SIMPLEX LOOSE COUPLER, DETECTOR AND
CONDENSER*. The base; the primary; the secondary; the pillar; the
switch; How to make the Simplex cat whisker detector; How to make the
Simplex fixed condenser; How to connect the apparatus; How to tune with
the loose coupler; How to adjust the detector.
Chapter V.—*TELEPHONE RECEIVERS AND HEADBANDS.*
Chapter VI.—*HOW TO BUILD THE SIMPLEX SPARK COIL.* The core; the
secondary; the condenser; the coil heads; the base; the interrupter
parts; the bridge.
Chapter VII.—*HOW TO MAKE THE SIMPLEX KEY*.
Chapter VIII.—*HOW TO CONNECT AND OPERATE THE APPARATUS*. How to connect
and operate a complete wireless station; How to operate; the code, etc.
*Three New Books on Home Made*
*Electrical Apparatus*
The Book you are now reading is only the first volume of "Home-made
Electrical Apparatus." Written in a very clear and simple style, the
other volumes are invaluable to the young experimenter. There are no old
or obsolete forms of apparatus described but only the latest electrical
devices, making them
*The Most Thorough and Complete Books for*
*the Young Electrical Experimenter Published*
The partial Table of Contents below only gives a small idea of the
interesting matter contained in these volumes.
VOLUME II
72 Pages 55 Illustrations
Table of Contents
Chapter VI—ELECTRICAL MEASURING INSTRUMENTS. Galvanometers, Ammeters,
Voltmeters, etc.
Chapter VII—CURRENT CONTROL DEVICES. How to Make a Pole Changing Switch
or Current Reverser. How to Reverse Small Motors. Battery Rheostats.
Chapter VIII—HOW TO MAKE A TELEGRAPH KEY AND SOUNDER. How to Install a
Telegraph Line and Learn to Operate. Learning the Morse Code.
Chapter IX—HOW TO MAKE AND INSTALL A TELEPHONE.
Chapter X—MEDICAL COILS AND SHOCKING COILS.
Chapter XI—THE CONSTRUCTION OF SPARK COILS. A one-quarter inch Coil, a
one-half inch Coil, a one inch Coil. Experiments with Spark Coils.
VOLUME III
80 Pages 73 Illustrations
Chapter XII—HOW TO MAKE A DYNAMO-MOTOR.
Chapter XIII—HOW TO MAKE A TOY BATTERY MOTOR.
Chapter XIV—HOW TO BUILD AN ELECTRIC ENGINE.
Chapter XV—MINIATURE BATTERY LAMP LIGHTING.
Chapter XVI—COHERER OUTFITS FOR WIRELESS TELEGRAPHY.
Chapter XVII—HOW TO BUILD A TESLA HIGH FREQUENCY COIL. Experiments with
High Frequency Currents.
Chapter XVIII—AN EXPERIMENTAL WIRELESS TELEPHONE.
Chapter XIX—MISCELLANEOUS APPARATUS. Electrolysis of Water.
Electro-Plating. Electricity from Heat. A Handy Light. An Experimental
Arc Lamp. A Magnetic Diver. Magnetic Fish. A Magnetic Clown. An Electric
Breeze. A Static Motor.
*Price Postpaid, 25 Cents per Volume*
All three volumes can be supplied bound together with handsome cloth
cover for $1.25 postpaid.
*Parts and Materials*
For Building the Apparatus Described in this Book
We have received so many requests from our customers for information as
to where they may obtain some of the materials required to build the
apparatus described in this book, that we have made arrangements to
supply same. Our business is essentially publishing, and we do not
intend to go into the manufacture of, or to push the sale of apparatus
or parts. Knowing, however, that many of our customers live where they
are remote from cities or suitable supply houses, where they might
obtain the necessary materials, we believe that the value of our books
will be increased ten fold to the reader if we are in a position to
furnish parts, etc.
*M500* Complete Set of Parts for Dynamo illustrated in Figure 132
*$3.75*
Shipping Weight, 5 lbs.
*M631* Complete Set of Parts for Tesla Coil *4.50*
Shipping Weight, 4 lbs.
*M631A*
Completed Tesla Coil *6.00*
Shipping Weight, 10 lbs.
*M631B*
Complete Tesla Coil Outfit, consisting of Tesla Coil, two-inch
Spark Coil, Spark Gap and Leyden Jars *25.00*
Shipping Weight, 25 lbs.
Please use list number when ordering. Include postage to pre-pay mailing
charges, or we will ship by Express Collect. No parts supplied other
than listed above. All prices subject to change without notice. Send for
latest price list.
*COLE & MORGAN, Inc.*
P.O. Box 473, City Hall Sta. New York, N. Y.