CHAPTER XXVII.

MISCELLANEOUS USES OF ELECTRICITY.

=171. The Many Uses= to which the electric current is put are almost

numberless. New uses are being found for it every day. Some of the

common applications are given below.

=172. Automatic Electric Program Clocks=, Fig. 252, are largely used

in all sorts of establishments, schools, etc., for ringing bells at

certain stated periods. The lower dial shown has many contact-points

that can be inserted to correspond to given times. As this revolves,

the circuits are closed, one after the other, and it may be so set that

bells will be rung in different parts of the house every five minutes,

if desired.

[Illustration: Fig. 252.]

[Illustration: Fig. 253.]

=173. Call Boxes= are used to send in calls of various kinds to

central stations. Fig. 253 shows one form. The number of different

calls provided includes messenger, carrier, coupé, express wagon,

doctor, laborer, police, fire, together with three more, which may be

made special to suit the convenience of the individual customer. The

instruments are provided with apparatus for receiving a return signal,

the object of which is to notify the subscriber that his call has been

received and is having attention.

[Illustration: Fig. 254.]

[Illustration: Fig. 255.]

Fig. 254 shows another form of call box, the handle being moved around

to the call desired. As it springs back to the original position, an

interrupted current passes through the box to the central station,

causing a bell to tap a certain number of times, giving the call and

location of the box.

=174. Electric Gas-Lighters.= Fig. 255 shows a _ratchet burner_. The

first pull of the chain turns on the gas through a four-way gas-cock,

governed by a ratchet-wheel and pawl. The issuing gas is lighted by a

wipe-spark at the tip of the burner. Alternate pulls shut off the gas.

As the lever brings the attached wire A, in contact with the wire B,

a bright spark passes, which ignites the gas, the burner being joined

with a battery and induction or spark coil.

_Automatic burners_ are used when it is desired to light gas at

a distance from the push-button. Fig. 256 shows one form. Two

electromagnets are shown, one being generally joined to a white

push-button for turning on the gas and lighting it, the other being

joined to a black button which turns off the gas when it is pressed.

The armatures of the magnets work the gas-valve. Sparks ignite the gas,

as explained above.

[Illustration: Fig. 256.]

[Illustration: Fig. 257.]

=175. Door Openers.= Fig. 257 shows one form. They contain

electromagnets so arranged that when the armature is attracted by the

pushing of a button anywhere in the building, the door can be pushed

open.

=176. Dental Outfits.= Fig. 258 shows a motor arranged to run dental

apparatus. The motor can be connected to an ordinary incandescent light

socket. In case the current gives out, the drills, etc., can be run by

foot power.

[Illustration: Fig. 258.]

=177. Annunciators= of various kinds are used in hotels, factories,

etc., to indicate a certain room when a bell rings at the office.

The bell indicates that some one has called, and the annunciator

shows the location of the call by displaying the number of the room

or its location. Fig. 259 shows a small annunciator. They contain

electromagnets which are connected to push-buttons located in the

building, and which bring the numbers into place as soon as the current

passes through them.

[Illustration: Fig. 259.]

INDEX.

Numbers refer to paragraphs. See Table of Contents for the titles of

the various chapters.

Action of magnets upon each other, 32.

Adjuster, for lamp cords, 151.

Air pressure, effect of spark upon, 155.

Aluminum-leaf, for electroscopes, 5.

Alternating current, 129, 130;

system of wiring for, 144.

Amalgamation of zincs, 47.

Amber, electrification upon, 3.

Ammeter, the, 74;

how placed in circuit, 77.

Ampere, the, 72.

Annunciators, 177.

Anode, 79, 82.

Apparatus for electrical measurements, Chap. VI.

Appliances, for distribution of currents, 141;

for electric railways, 167;

for heating by electricity, 147.

Arc, the electric, 152.

Arc lamp, the, 153;

how light is produced by, Chap. XXII.;

double carbon, 153;

hand-feed focussing, 153;

for search-lights, 153;

short, for basements, 153;

single carbon, 153;

for theater use, 153.

Armature, of dynamo, 127, 129;

of electromagnets, 98;

of horseshoe magnet, 26;

of motors, 161;

uses of, 39.

Artificial magnets, 25.

Astatic, detectors, 94;

galvanometer, 73;

needles, 94.

Aurora borealis, 23.

Automatic, current interrupters, 104, 115;

gas lighters, 174;

program clocks, 172.

Automobiles, 169;

controllers for, 169;

motors for, 169;

steering of, 169;

storage batteries for, 169.

Bamboo filaments, 149.

Bar magnets, 27;

magnetic figures of, 38.

Batteries, large plunge, 54;

plunge, 53;

secondary, 86;

storage, and how they work, Chap. IX.

Bell, the electric, and some of its uses, Chap. XV.;

electric, 116;

magneto testing, 117;

trembling, etc., 116.

Bell transmitter, 120.

Belts, electricity generated by friction upon, 1.

Benjamin Franklin, 18.

Bichromate of potash cells, 51, etc.

Binding-posts, Chap. V.;

common forms of, 63.

Blasting, by electricity, 147;

electric machines for, 147.

Bluestone cell, 56.

Boats, electric, 168.

Boilers, use of in central stations, 170.

Bones, photographed by x-rays, Chap. XXIII.

Boosters, 136.

Brushes, 129.

Bunsen cells, 56_a_.

Burner, automatic, 174;

for gas-lights, 174;

ratchet, 174.

Buzzers, electric, 118.

Cables and wires, 143.

Call boxes, electric, 173.

Carbon, in arc lamps, 152, 153;

filament, 149;

transmitter, 123.

Carpet, electricity generated upon, 1.

Cars, electric, 164;

controllers for, 165;

heating by electricity, 167;

overhead system for, 166;

underground system for, 166.

Cat, electricity generated upon, 1.

Cathode, definition of, 79;

rays, 157.

Cells, Bunsen, 56_a_;

bichromate of potash, 51;

closed circuit, 50;

dry, 58;

Edison-Lelande, 59;

electricity generated by, Chap. III.;

Fuller, 55;

Gonda, 57;

gravity, 56;

Grenet, 52;

Leclanché, 57;

open circuit, 50;

plates and poles of, 45_a_;

polarization of, 48;

simple, 45, 49;

single-fluid, 49;

two-fluid, 49;

various voltaic, Chap. IV.

Central stations, 170;

a word about, Chap. XXVI.

Chain lightning, 19.

Chafing-dishes, electrical, 147.

Charging condensers, 15.

Chemical action, and electricity, 81.

Chemical effects of electric current, Chap. VII.

Chemical meters, 78.

Church organs, pumped by motors, 162.

Circuits, electric, 50;

for lamps, 144.

Cleats, porcelain, 141;

wooden, 141.

Clocks, automatic electric, 172.

Closed circuit cells, 50.

Coils, induction, and how they work, Chap. XIII.;

induction, construction of, 104;

method of joining, 98;

primary and secondary, 103;

resistance, 69;

rotation of, 95;

of transformers, 135.

Collectors on dynamos, 129.

Commutators, 129.

Compasses, magnetic, 31.

Compound, magnets, 28;

wound dynamo, 131.

Condensation of static electricity, 15.

Condensers, 15;

for induction coils, 104.

Conductors, and insulators, 4, 138.

Conduits, electric, 140.

Connections, electrical, 60;

for telegraph lines, 111.

Controllers, for automobiles, 169;

for electric cars, 165.

Copper sulphate, effects of current on, 82;

formula of, 79.

Copper voltameters, 75.

Cords, adjustable for lamps, 151.

Coulomb, the, 76.

Crater of hot carbons, 152.

Crookes tubes, 156, 158.

Current, detectors, 93;

direction of in cell, 46;

from magnet and coil, 100;

from two coils, 102;

induced, 127;

of induction coils, 105;

interrupters, automatic, 104, 115;

local, 47;

primary and secondary, 102;

transformation of, Chap. XVIII.;

transmission of, 134.

Currents, and motion, 160;

how distributed for use, Chap. XIX.

Current strength, 71;

measurement of, 73;

unit of, 72.

Cylinder electric machines, 9.

Daniell cell, 56.

D'Arsonval galvanometer, 73.

Declination, 41.

Decorative incandescent lamps, 151.

Dental, lamps, 151;

outfits, 176.

Detectors, astatic, 94;

current, 93.

Diamagnetic bodies, 29.

Diaphragm for telephones, 120.

Dip, of magnetic needle, 42.

Direct current, 129, 130.

Direction of current in cell, 46.

Discharging condensers, 15.

Disruptive discharges, 154.

Distribution of currents for use, Chap. XIX.

Door opener, electric, 175.

Dots and dashes, 110.

Drill press, run by motor, 162.

Dry cells, 58.

Dynamo, the, 126;

alternating current, 130;

commutator of, 129;

compound wound, 131;

direct current, 130;

lamps connected to, 132;

series wound, 131;

shunt wound, 131;

used as motor, 161;

use of in central stations, 170;

used with water power, 170.

Dynamos, electricity generated by, Chap. XVII.;

types of, 130;

various machines, 132;

winding of, 131.

Dynamotors, 137.

Earth, inductive influence of, 43;

lines of force about, 40, 42.

Ebonite, electricity by friction upon, 3, 4.

Edison-Lelande cells, 59.

Electric, automobiles, 169;

bell, and some of its uses, Chap. XV.;

boats, 168;

buzzers, 118;

cars, 164;

conduits, 140;

fans, 162;

flat-irons, 146;

gas lighters, 174;

griddles, 147;

kitchen, 147;

lights, arc, Chap. XXII.;

lights, incandescent, Chap. XXI.;

machines, static, 7 to 13;

machines, uses of, 14;

motor, the, 161;

motor, and how it does work, Chap. XXIV.;

soldering irons, 146;

telegraph, and how it sends messages, Chap. XIV.;

telephone, and how it transmits speech, Chap. XVI.;

welding, 146.

Electric current, and work, 133;

and chemical action, 81;

chemical effects of, Chap. VII.;

how distributed for use, Chap. XIX.;

magnetic effects of, Chap. XI.;

how transformed, Chap. XVIII.

Electrical, connections, 60;

horse-power, 77;

measurements, Chap. VI.;

resistance, 68;

resistance, unit of, 69;

units, Chap. VI.

Electricity, about frictional, Chap. I.;

and chemical action, 81;

atmospheric, 18;

heat produced by, Chap. XX.;

history of, 3;

how generated upon cat, 1;

how generated by dynamos, Chap. XVII.;

how generated by heat, Chap. X.;

how generated by induction, Chap. XII.;

how generated by voltaic cell, Chap. III.;

origin of name, 2.

Electrification, kinds of, 6;

laws of, 7.

Electrolysis, 79.

Electrolyte, 79.

Electromagnetic induction, 99.

Electromagnetism, 91.

Electromagnets, 96;

forms of, 97.

Electro-mechanical gong, 116.

Electromotive force, defined, 65, 71;

measurement of, 67;

of polarization, 85;

of static electricity, 17;

unit of, 66.

Electrophorus, the, 8.

Electroplating, 82.

Electroscopes, 5.

Electrotyping, 83.

Experiments, early, with currents, 44;

some simple, 1.

External resistance, 68.

Fan motors, 162.

Field, magnetic, 37.

Field-magnets, 129.

Figures, magnetic, 38.

Filaments, carbon, 149;

bamboo, etc., 149.

Fire, St. Elmo's, 22.

Flat-irons, electric, 147.

Floor mains, 139.

Fluoroscope, 158.

Force, and induced currents, 101;

lines of magnetic, 38;

lines of about a wire, 92, 96;

lines of about a magnet, 37, 38.

Frictional electricity, about, Chap, I.;

location of charge of, 4;

sparks from, 4.

Fuller cell, the, 55.

Fuse, link, 142;

plug, 142;

ribbons, 142;

wire, 142.

Fusible rosettes, 142.

Galvani, early experiments of, 44.

Galvanometers, 73;

astatic, 73;

considered as motor, 161;

D'Arsonval, 73;

tangent, 73.

Galvanoscope, 73;

astatic, 94.

Gas lighters, electric, 174.

Geissler tubes, 156.

Generators, electric, 126.

Glass, electricity generated upon, 4.

Glue pots, electric, 147.

Gold-leaf, for electroscopes, 5.

Gold plating, 82.

Gonda cell, 57.

Gong, electro-mechanical, 116.

Gravity cell, the, 56;

replaced by dynamotors, 137.

Grenet cell, 52.

Griddles, electric, 147.

Guard, for lamps, 151.

Heat, how generated by electricity, Chap. X.;

and magnetism, 35;

and resistance, 145.

Heat lightning, 19.

Heaters, for cars, 167.

History of electricity, 3.

Horse-power, electrical, 77.

Horseshoe, permanent magnets, 26;

electromagnets, 97, 98.

Human body, bones of, photographed by x-rays, Chap. XXIII.

Hydrogen, action of in cell, 48;

attraction of for oxygen, 85.

Incandescence, 148.

Incandescent lamp, 149;

candle-power of, 150;

current for, 150;

light produced by, Chap. XXI.;

construction of, 149;

uses of, 151.

Inclination of magnetic needle, 42.

Indicating push-button, 61.

Induced currents, 127;

and lines of force, 101;

by rotary motion, 128;

of induction coils, 105;

of transformers, 135.

Induced magnetism, 36.

Induction, electricity generated by, Chap. XII.;

electromagnetic, 99.

Induction coils, condensers for, 104;

construction of, 104;

currents of, 105;

how they work, Chap. XIII.;

in telephone work, 124;

uses of, 106.

Inductive influence of earth, 43.

Influence machines for medical purposes, 13.

Ink writing registers, 114.

Insulating tubing, 141.

Insulators, 141;

and conductors, 4, 138;

feeder-wire, 167;

for poles, 167;

porcelain, 141.

Internal resistance, 68.

Interrupters, automatic current, 104, 115.

Ions, 80.

Iron, electricity upon, by friction, 4.

Jar, Leyden, 15.

Jarring magnets, effects of, 33.

Keeper of magnets, 26.

Keys, telegraph, 109.

Kinds of electrification, 6.

Kitchen, electric, 147.

Knife switch, 62.

Lamp, incandescent, candle-power of, 150;

cord, adjustable, 151;

current for, 150;

dental, 151;

for desks, 151;

for throat, 151;

guard for, 151;

incandescent, 149;

socket, 151;

with half shade, 151.

Lamp, the arc, 153;

how light is produced by, Chap. XXII.;

double carbon, 153;

hand-feed focussing, 153;

for search-lights, 153;

single carbon, 153;

short, for basements, 153;

for theater use, 153.

Lamp circuits, alternating system, 144.

Lamps, in parallel, 144;

lamps in series, 144;

three-wire system, 144;

two-wire system, 144.

Laws, of electrification, 7;

of magnetic attraction, 32;

of resistance, 70.

Leaf electroscopes, 5.

Leclanché cell, 57.

Leyden, battery, 16;

jar, 15.

Light, how produced by arc lamp, Chap. XXII.;

how produced by incandescent lamp, Chap. XXI.

Lightning, 19;

rods, 21.

Line, telegraph, Chap. XIV.;

connections for, 111;

operation of, 112.

Line suspension, for trolley-wires, 167.

Line wire, 111.

Lines of force, conductors of, 39, 96;

about the earth, 40, 42;

and induced currents, 101;

about a magnet, 38;

about a wire, 92.

Local currents, 47.

Magnetic, bodies, 29;

declination, 41;

effects of electric current, Chap. XI.;

field, 37;

figure of one bar magnet, 38;

figure of two bar magnets, 38;

figure of horseshoe magnet, 38;

needle, dip of, 42;

needles and compasses, 31.

Magnetism, and heat, 35;

induced, 36;

laws of, 32;

residual, 34;

retentivity, 34;

temporary, 36;

terrestrial, 40;

theory of, 33.

Magneto, signal bells, 117;

testing bells, 117;

transmitter, 120.

Magnets, action upon each other, 32;

artificial, 25;

bar, 27;

compound, 28;

effects of jarring, 33;

electro, 96;

electro, forms of, 97;

horseshoe, 26;

and magnetism, about, Chap. II.;

making of, 30;

natural, 24.

Mains, electric, 139.

Man-holes, in conduits, 140.

Measurements, electric, Chap. VI.;

of current strength, 73;

of E.M.F., 67.

Meters, chemical, 78;

permanent record, 77.

Microphone, the, 122.

Motion and currents, 160.

Motor, acting like dynamo, 163;

armature of, 161;

controlling speed of, 165;

electric, 161;

electric, and how it does work, Chap. XXIV.;

fans, 162;

for automobiles, 169;

for boats, 168;

for pumping bellows, 162;

for running drill press, 162;

parts of, 162;

starting boxes for, 163;

uses of, 162.

Motor-dynamos, 136.

Mouldings, for wires, 141.

Name, electricity, origin of, 2.

Natural magnets, 24.

Needles, astatic, 94;

dipping, 42;

magnetic, 31.

Negative electrification, 5.

Non-conductors, 4.

North pole, magnetic of earth, 40;

of magnets, 26.

Northern lights, 23.

Ohm, the, 69.

Open circuit cells, 50.

Openers, for doors, 175.

Outfits, dental, 175.

Overhead trolley system, 166.

Oxygen, attraction for hydrogen, 85.

Parallel arrangement of lamps, 144.

Peltier effect, 89.

Pendant, electric, 151.

Pith-ball electroscope, 5.

Plate electrical machine, 10.

Plates of cells, 45_a_.

Plunge batteries, 53;

large, 54.

Polarity of coils, 95.

Polarization, 84;

electromotive force of, 85;

of cells, 48.

Pole-changing switch, 62.

Poles, of cells, 45_a_;

of horseshoe magnet, 26.

Positive electrification, 6.

Potential, defined, 65.

Push-buttons, Chap. V.;

indicating, 61;

modifications of, 61;

table clamp, 61.

Quantity of electricity, 76;

unit of, 76.

Rays, cathode, 157;

x-rays, 158.

Receiver, telephone, 121.

Reflectors, for lamps, 151.

Registers, ink writing, 114.

Relay, the, 113.

Residual magnetism, 34.

Resistance, coils and boxes, 69;

electrical, 68;

external, 68;

and heat, 145;

internal, 68;

laws of, 70;

unit of, 69.

Retentivity, 34.

Risers, in buildings, 139.

Rods, lightning, 21.

Roentgen, Prof., 158.

Rosette, fusible, 142.

Running-gear, of automobiles, 169.

Safety, devices, 142;

fuse, 142;

fuse link, 142;

fuse plug, 142;

fuse ribbon, 142;

fuse wire, 142.

Search-lights, 153;

signals sent by, 153.

Secondary batteries, 86;

uses of, 87.

Series arrangement of lamps, 144.

Series wound dynamo, 131.

Service wires, 139.

Shunt-wound dynamo, 131.

Signal bells, magneto, 117.

Simple cell, the, 45, 49.

Single-fluid cells, 49.

Single-point switch, 62.

Single-stroke bell, 116.

Socket, for incandescent lamps, 151.

Soldering irons, electric, 147.

Sounders, telegraph, 110;

home-made, 110.

Spark, effect of air pressure on, 155.

Sparks, from cells, 17;

from frictional electricity, 4.

St. Elmo's fire, 22.

Starting boxes, for motors, 163.

Static electric machines, 8.

Static electricity, condensation of, 15;

electromotive force of, 17;

to test presence of, 5;

uses of, 14.

Steam engines, in central stations, 170.

Steel, inductive influence of earth upon, 43;

retentivity of, 26.

Storage batteries, the, and how they work, Chap. IX.;

for automobiles, 169;

for boats, 168;

for natural sources of power, 87.

Stoves, electric, 147.

Strength of current, 71;

measurement of, 73;

unit of, 72.

Switchboards, 62.

Switches, Chap. V.;

knife, 62;

pole-changing, 62;

single point, 62;

for trolley lines, 167.

Table clamp-push, 61.

Tangent galvanometer, 73.

Teakettles, electric, 147.

Telegraph, electric, and how it sends messages, Chap. XIV.;

ink writing registers, 114;

keys, 109;

relay, 113;

sounders, 110.

Telegraph line, 107, 108;

operation of, 112;

simple connections of, 111.

Telephone, the, and how it transmits speech, Chap. XVI.;

receiver, 121;

transmitter, 120;

use of induction coil with, 124;

various forms of, 125.

Temporary magnetism, 36.

Terrestrial magnetism, 40.

Theory of magnetism, 33.

Thermoelectricity, 88.

Thermopiles, 90.

Three-wire system, 144.

Throat, lamp for, 151.

Thunder, 20.

Toepler-Holtz machines, 11.

Transformers, 135.

Transforming electric current, Chap. XVIII.;

for electric welding, 146.

Transmission of currents, 134.

Transmitter, Bell, 120;

carbon, 123.

Trembling bell, 116.

Trolley-wires, 164;

-poles, 164;

-wheels, 164.

Tubes, Crookes, 156, 158;

Geissler, 156;

vacuum, 156.

Two-fluid cells, 49.

Two-wire system, 144.

Underground trolley system 166;

conduits for, 166.

Unit, of current strength, 72;

of electromotive force, 66;

of quantity, 76;

of resistance, 69.

Units, electrical, Chap. VI.

Uses, of armatures, 39;

of electricity, miscellaneous, Chap. XXVII.;

of induction coils, 106;

of motors, 162;

of storage batteries, 87.

Vacuum-tubes, 156.

Variation, angle of, 41.

Volt, the, 66.

Volta, 66;

early experiments of, 44.

Voltaic cell, electricity generated by, Chap. III.

Voltaic pile, 44.

Voltameters, 75;

copper, 75;

water, 75.

Voltmeters, 67, 77.

Water, decomposition of, 79;

power, source of energy, 170;

voltameters, 73.

Watt, the, 77.

Wattmeters, 77.

Welding, electric, 146.

Wimshurst electric machine, 12.

Wires and cables, 143.

Wiring, for alternating system, 144;

three-wire system, 144;

two-wire system, 144.

Work, and electric current, 133.

X-ray photographs, 159.

X-rays, 156;

and how the bones of the human body are photographed, Chap. XXIII.

Yokes, 97, 98.

Zincs, amalgamation of, 47.

THINGS A BOY SHOULD KNOW ABOUT ELECTRICITY.

By THOMAS M. ST. JOHN, Met. E.

The book contains 180 pages, and 260 illustrations; it measures

5 x 7½ in., and is bound in cloth.

PRICE, POST-PAID, $1.00.

=CONTENTS:= _Chapter_ I. About Frictional Electricity.--II.

About Magnets and Magnetism.--III. How Electricity

is Generated by the Voltaic Cell.--IV. Various

Voltaic Cells.--V. About Push-Buttons, Switches and

Binding-Posts.--VI. Units and Apparatus for Electrical

Measurements.--VII. Chemical Effects of the Electric

Current.--VIII. How Electroplating and Electrotyping are

Done.--IX. The Storage Battery and How it Works.--X. How

Electricity is Generated by Heat.--XI. Magnetic Effects of

the Electric Current.--XII. How Electricity is Generated

by Induction.--XIII. How the Induction Coil Works.--XIV.

The Electric Telegraph, and How it Sends Messages.--XV. The

Electric Bell and Some of its Uses.--XVI. The Telephone,

and How it Transmits Speech.--XVII. How Electricity

is Generated by Dynamos.--XVIII. How the Electric

Current is Transformed.--XIX. How Electric Currents are

Distributed for Use.--XX. How Heat is Produced by the

Electric Current.--XXI. How Light is Produced by the

Incandescent Lamp.--XXII. How Light is Produced by the Arc

Lamp.--XXIII. X-Rays, and How the Bones of the Human Body

are Photographed.--XXIV. The Electric Motor and How it Does

Work.--XXV. Electric Cars, Boats and Automobiles.--XXVI. A

Word About Central Stations.--XXVII. Miscellaneous Uses of

Electricity.

This book explains, in simple, straightforward language, many things

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It is free from technical language and rhetorical frills, but it tells

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It is brimful of illustrations--the best that can be had--illustrations

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This book does not contain experiments, or tell how to make apparatus;

our other books do that. After explaining the simple principles of

electricity, it shows how these principles are used and combined to

make electricity do every-day work.

_Everyone Should Know About Electricity._

A VERY APPROPRIATE PRESENT

THIRD EDITION

How Two Boys Made Their Own Electrical Apparatus.

Containing complete directions for making all kinds of

simple electrical apparatus for the study of elementary

electricity. By PROFESSOR THOMAS M. ST. JOHN, New York City.

The book measures 5 × 7½ in., and is beautifully bound in

cloth. It contains 141 pages and 125 illustrations. Complete

directions are given for making 152 different pieces of

Apparatus for the practical use of students, teachers, and

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PRICE, POST-PAID, $1.00.

The shocking coils, telegraph instruments, batteries, electromagnets,

motors, etc., etc., are so simple in construction that any boy of

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The author has been working along this line for several years, and he

has been able, _with the help of boys_, to devise a complete line of

simple electrical apparatus.

=_THE APPARATUS IS SIMPLE because the designs and methods

of construction have been worked out practically in the

school-room, absolutely no machine-work being required._=

=_THE APPARATUS IS PRACTICAL because it has been designed

for real use in the experimental study of elementary

electricity._=

=_THE APPARATUS IS CHEAP because most of the parts can be

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and wood._=

=Address, THOMAS M. ST. JOHN,=

=407 West 51st Street,=

=New York.=

How Two Boys Made Their Own Electrical Apparatus.

=CONTENTS:= _Chapter_ I. Cells and Batteries.--II. Battery Fluids

and Solutions.--III. Miscellaneous Apparatus and Methods of

Construction.--IV. Switches and Cut-Outs.--V. Binding-Posts and

Connectors.--VI. Permanent Magnets,--VII. Magnetic Needles and

Compasses.--VIII. Yokes and Armatures.--IX. Electro-Magnets.--X.

Wire-Winding Apparatus.--XI. Induction Coils and Their

Attachments.--XII. Contact Breakers and Current Interrupters.--XIII.

Current Detectors and Galvanometers.--XIV. Telegraph Keys and

Sounders.--XV. Electric Bells and Buzzers.--XVI. Commutators and

Current Reversers.--XVII. Resistance Coils.--XVIII. Apparatus for

Static Electricity.--XIX. Electric Motors.--XX. Odds and Ends.--XXI.

Tools and Materials.

"The author of this book is a teacher and wirier of great ingenuity,

and we imagine that the effect of such a book as this falling into

juvenile hands must be highly stimulating and beneficial. It is

full of explicit details and instructions in regard to a great

variety of apparatus, and the materials required are all within the

compass of very modest pocket-money. Moreover, it is systematic and

entirely without rhetorical frills, so that the student can go right

along without being diverted from good helpful work that will lead

him to build useful apparatus and make him understand what he is

about. The drawings are plain and excellent. We heartily commend the

book."--_Electrical Engineer._

"Those who visited the electrical exhibition last May cannot have

failed to notice on the south gallery a very interesting exhibit,

consisting, as it did, of electrical apparatus made by boys. The

various devices there shown, comprising electro-magnets, telegraph keys

and sounders, resistance coils, etc., were turned out by boys following

the instructions given in the book with the above title, which is

unquestionably one of the most practical little works yet written that

treat of similar subjects, for with but a limited amount of mechanical

knowledge, and by closely following the instructions given, almost any

electrical device may be made at very small expense. That such a book

fills a long-felt want may be inferred from the number of inquiries

we are constantly receiving from persons desiring to make their own

induction coils and other apparatus."--_Electricity._

"At the electrical show in New York last May one of the most

interesting exhibits was that of simple electrical apparatus made by

the boys in one of the private schools in the city. This apparatus,

made by boys of thirteen to fifteen years of age, was from designs

by the author of this clever little book, and it was remarkable to

see what an ingenious use had been made of old tin tomato-cans,

cracker-boxes, bolts, screws, wire, and wood. With these simple

materials telegraph instruments, coils, buzzers, current detectors,

motors, switches, armatures, and an almost endless variety of apparatus

were made, In this book Mr. St. John has given directions in simple

language for making and using these devices, and has illustrated

these directions with admirable diagrams and cuts. The little volume

is unique, and will prove exceedingly helpful to those of our young

readers who are fortunate enough to possess themselves of a copy. For

schools where a course of elementary science is taught, no better

text-book in the first-steps in electricity is obtainable."--_The Great

Round World._

Exhibit of Experimental Electrical Apparatus

AT THE ELECTRICAL SHOW, MADISON SQUARE GARDEN, NEW YORK.

While only 40 pieces of simple apparatus were shown in this exhibit, it

gave visitors something of an idea of what young boys can do if given

proper designs.

[Illustration: "HOW TWO BOYS MADE THEIR OWN ELECTRICAL APPARATUS"

Gives Proper Designs--Designs for over 150 Things.]

Fun With Photography

BOOK AND COMPLETE OUTFIT.

[Illustration]

=PHOTOGRAPHY= is now an educational amusement, and to many it is the

most fascinating of all amusements. The magic of sunshine, the wonders

of nature, and the beauties of art are tools in the hand of the amateur

photographer.

A great many things can be done with this outfit, and it will give an

insight into this most popular pastime.

=THE OUTFIT= contains everything necessary for making

ordinary prints--together with other articles to be used

in various ways. The following things are included:

One Illustrated Book of Instructions, called "Fun With

Photography;" 1 Package of Sensitized Paper; 1 Printing

Frame, including Glass, Back, and Spring; 1 Set of Masks for

Printing Frame; 1 Set of Patterns for Fancy Shapes; 1 Book

of Negatives (Patent Pending) Ready for Use; 6 Sheets of

Blank Negative Paper; 1 Alphabet Sheet; 1 Package of Card

Mounts; 1 Package of Folding Mounts; 1 Package of "Fixo."

=CONTENTS OF BOOK:=--=Chapter I.

Introduction.=--Photography.--Magic Sunshine.--The

Outfit.--=II. General Instructions.=--The

Sensitized Paper.--How the Effects are

Produced.--Negatives.--Prints.--Printing Frames.--Our

Printing Frame.--Putting Negatives in Printing

Frame.--Printing.--Developing.--Fixing.--Drying.--Trimming.--Fancy

Shapes.--Mounting.--=III. Negatives and How to Make

Them.=--The Paper.--Making Transparent Paper.--Making

the Negatives.--Printed Negatives.--Perforated

Negatives.--Negatives Made from Magazine Pictures.--Ground

Glass Negatives.--=IV. Nature Photography.=--Aids

to Nature Study.--Ferns and Leaves.--Photographing

Leaves.--Perforating Leaves.--Drying Leaves, Ferns,

etc., for Negatives.--Flowers.--=V. Miscellaneous

Photographs.=--Magnetic Photographs.--Combination

Pictures.--Initial Pictures.--Name Plates.--Christmas,

Easter and Birthday Cards.

_The Book and Complete Outfit will be sent, by mail or

express, Charges Prepaid, upon receipt of 65 Cents, by_

=THOMAS M. ST. JOHN, 407 W. 51st St., New York.=

Fun With Magnetism.

BOOK AND COMPLETE OUTFIT FOR SIXTY-ONE EXPERIMENTS IN MAGNETISM...

[Illustration]

Children like to do experiments; and in this way, better than in any

other, _a practical knowledge of the elements of magnetism_ may be

obtained.

These experiments, although arranged to _amuse_ boys and girls, have

been found to be very _useful in the class-room_ to supplement the

ordinary exercises given in text-books of science.

To secure the _best possible quality of apparatus_, the horseshoe

magnets were made at Sheffield, England, especially for these sets.

They are new and strong. Other parts of the apparatus have also been

selected and made with great care, to adapt them particularly to these

experiments.--_From the author's preface._

=CONTENTS.=--Experiments With Horseshoe Magnet.--Experiments

With Magnetized Needles.--Experiments With Needles,

Corks, Wires, Nails, etc.--Experiments With Bar

Magnets.--Experiments With Floating Magnets.--Miscellaneous

Experiments.--Miscellaneous Illustrations showing what very

small children can do with the Apparatus.--Diagrams showing

how Magnetized Needles may be used by little children to

make hundreds of pretty designs upon paper.

=AMUSING EXPERIMENTS.=--Something for Nervous People to

Try.--The Jersey Mosquito.--The Stampede.--The Runaway.--The

Dog-fight.--The Whirligig.--The Naval Battle.--A

String of Fish.--A Magnetic Gun.--A Top Upsidedown.--A

Magnetic Windmill.--A Compass Upsidedown.--The Magnetic

Acrobat.--The Busy Ant-hill.--The Magnetic Bridge.--The

Merry-go-Round.--The Tight-rope Walker.--A Magnetic Motor

Using Attractions and Repulsions.

_The Book and Complete Outfit will be sent, Post-paid,

upon receipt of 35 Cents, by_

=THOMAS M. ST. JOHN, 407 W. 51st St., New York.=

FUN WITH SHADOWS

BOOK AND COMPLETE OUTFIT FOR SHADOW PICTURES, PANTOMIMES,

ENTERTAINMENTS, Etc., Etc.

[Illustration]

=Shadow Making= has been a very popular amusement for several

centuries. There is a great deal of _fun_ and instruction in it, and

its long life is due to the fact that it has always been a source of

keen delight to grown people as well as to children.

In getting material together for this little book, the author has been

greatly aided by English, French and American authors, some of whom are

professional shadowists. It has been the author's special effort to get

the subject and apparatus into a practical, cheap form for boys and

girls.

=THE OUTFIT= contains everything necessary for all ordinary

shadow pictures, shadow entertainments, shadow plays, etc.

The following articles are included:

One book of Instructions called "Fun with Shadows"; 1 Shadow

Screen; 2 Sheets of Tracing Paper; 1 Coil of Wire for

Movable Figures; 1 Cardboard Frame for Circular Screen; 1

Cardboard House for Stage Scenery; 1 Jointed Wire Fish-pole

and Line; 2 Bent Wire Scenery Holders; 4 Clamps for Screen;

1 Wire Figure Support; 1 Wire for Oar; 2 Spring Wire Table

Clamps; 1 Wire Candlestick Holder; 5 Cardboard Plates

containing the following printed figures that should be cut

out with shears: 12 Character Hats; 1 Boat; 1 Oar-blade; 1

Fish; 1 Candlestick; 1 Cardboard Plate containing printed

parts for making movable figures.

=CONTENTS OF BOOK:= One Hundred Illustrations and Diagrams,

including Ten Full-page Book Plates, together with Six

Full-page Plates on Cardboard.

_Chapter_ I. Introduction.--II. General Instructions.--III.

Hand Shadows of Animals.--IV. Hand Shadows of Heads,

Character Faces, etc.--V. Moving Shadow Figures and How

to Make Them.--VI. Shadow Pantomimes.--VII. Miscellaneous

Shadows.

_The Book and Complete Outfit will be sent, =POST-PAID=,

upon receipt of 35 cents, by_

=THOMAS M. ST. JOHN, 407 West 51st St., New York City.=

Fun With Electricity.

BOOK AND COMPLETE OUTFIT FOR SIXTY EXPERIMENTS IN ELECTRICITY....

[Illustration]

Enough of the principles of electricity are brought out to make the

book instructive as well as amusing. The experiments are systematically

arranged, and make a fascinating science course. No chemicals, no

danger.

The book is conversational and not at all "schooly," Harry and Ned

being two boys who perform the experiments and talk over the results as

they go along.

"The book reads like a story."--"An appropriate present for a

boy or girl."--"Intelligent parents will appreciate 'Fun With

Electricity.'"--"Very complete, because it contains both book and

apparatus."--"There is no end to the fun which a boy or girl can have

with this fascinating amusement."

=THERE IS FUN IN THESE EXPERIMENTS.=--Chain Lightning.--An

Electric Whirligig.--The Baby Thunderstorm.--A Race

with Electricity.--An Electric Frog Pond.--An Electric

Ding-Dong.--The Magic Finger.--Daddy Long-Legs.--Jumping

Sally.--An Electric Kite.--Very Shocking.--Condensed

Lightning.--An Electric Fly-Trap.--The Merry Pendulum.--An

Electric Ferry-Boat.--A Funny Piece of Paper.--A Joke on the

Family Cat.--Electricity Plays Leap-Frog.--Lightning Goes

Over a Bridge.--Electricity Carries a Lantern.--And _=40

Others=_.

The =_OUTFIT_= contains 20 different articles. The =_BOOK

OF INSTRUCTION=_ measures 5 x 7½ inches, and has 38

illustrations, 55 pages, good paper and clear type.

_The Book, and Complete Outfit will be sent, by mail or

express, Charges Prepaid, upon receipt of 65 Cents, by_

=THOMAS M. ST. JOHN, 407 W. 51st St., New York.=

Fun With Puzzles.

BOOK, KEY, AND COMPLETE OUTFIT FOR FOUR HUNDRED PUZZLES...

The BOOK measures 5 × 7½ inches. It is well printed, nicely bound,

and contains 15 chapters, 80 pages, and 128 illustrations. The KEY is

illustrated. It is bound with the book, and contains the solution of

every puzzle. The COMPLETE OUTFIT is placed in a neat box with the

book. It consists of numbers, counters, figures, pictures, etc., for

doing the puzzles.

=CONTENTS:= _Chapter_ (1) Secret Writing. (2) Magic

Triangles, Squares, Rectangles, Hexagons, Crosses, Circles,

etc. (3) Dropped Letter and Dropped Word Puzzles. (4) Mixed

Proverbs, Prose and Rhyme. (5) Word Diamonds, Squares,

Triangles, and Rhomboids. (6) Numerical Enigmas. (7)

Jumbled Writing and Magic Proverbs. (8) Dissected Puzzles.

(9) Hidden and Concealed Words. (10) Divided Cakes, Pies,

Gardens, Farms, etc. (11) Bicycle and Boat Puzzles. (12)

Various Word and Letter Puzzles. (13) Puzzles with Counters.

(14) Combination Puzzles. (15) Mazes and Labyrinths.

"Fun With Puzzles" is a book that every boy and girl should have. It

is amusing, instructive,--educational. It is just the thing to wake up

boys and girls and make them think. They like it, because it is real

fun. This sort of educational play should be given in every school-room

and in every home.

"Fun With Puzzles" will puzzle your friends, as well as yourself; it

contains some real brain-splitters. Over 300 new and original puzzles

are given, besides many that are hundreds of years old.

=Secret Writing.= Among the many things that "F. W. P." contains, is

the key to _secret writing_. It shows you a very simple way to write

letters to your friends, and it is simply impossible for others to read

what you have written, unless they know the secret. This, alone is a

valuable thing for any boy or girl who wants to have some fun.

_The Book, Key, and Complete Outfit will be sent, postpaid,

upon receipt of 35 cents, by_

=THOMAS M. ST. JOHN, 407 West 51st St., New York City.=

Fun With Soap-Bubbles.

BOOK AND COMPLETE OUTFIT FOR FANCY BUBBLES AND FILMS....

[Illustration]

=THE OUTFIT= contains everything necessary for thousands of beautiful

bubbles and films. All highly colored articles have been carefully

avoided, as cheap paints and dyes are positively dangerous in

children's mouths. The outfit contains the following articles:

One Book of Instructions, called "Fun With Soap-Bubbles," 1 Metal Base

for Bubble Stand, 1 Wooden Rod for Bubble Stand, 3 Large Wire Rings for

Bubble Stand, 1 Small Wire Ring, 3 Straws, 1 Package of Prepared Soap,

1 Bubble Pipe, 1 Water-proof Bubble Horn. The complete outfit is placed

in a neat box with the book. (Extra Horns, Soap, etc., furnished at

slight cost.)

=CONTENTS OF BOOK.=--Twenty-one

Illustrations.--Introduction.--The Colors of

Soap-bubbles.--The Outfit.--Soap Mixture.--Useful

Hints.--Bubbles Blown With Pipes.--Bubbles Blown

With Straws.--Bubbles Blown With the Horn.--Floating

Bubbles.--Baby Bubbles.--Smoke Bubbles.--Bombshell

Bubbles.--Dancing Bubbles.--Bubble Games.--Supported

Bubbles.--Bubble Cluster.--Suspended Bubbles.--Bubble

Lamp Chimney.--Bubble Lenses.--Bubble Basket.--Bubble

Bellows.--To Draw a Bubble Through a Ring.--Bubble

Acorn.--Bubble Bottle.--A Bubble Within a Bubble.--Another

Way.--Bubble Shade.--Bubble Hammock.--Wrestling

Bubbles.--A Smoking Bubble.--Soap Films.--The Tennis

Racket Film.--Fish-net Film.--Pan-shaped Film.--Bow and

Arrow Film.--Bubble Dome.--Double Bubble Dome.--Pyramid

Bubbles.--Turtle-back Bubbles.--Soap-bubbles and Frictional

Electricity.

"There is nothing more beautiful than the airy-fairy soap-bubble with

its everchanging colors."

_THE BEST POSSIBLE AMUSEMENT FOR OLD

AND YOUNG._

_The Book and Complete Outfit will be sent, =POST-PAID=,

upon receipt of 35 cents, by_

=THOMAS M. ST. JOHN, 407 West 51st St., New York City.=

The Study of Elementary Electricity and

Magnetism by Experiment.

By THOMAS M. ST. JOHN, Met. E.

The book contains 220 pages and 168 illustrations;

it measures 5 × 7½ in. and is bound in green cloth.

PRICE, POST-PAID, $1.25.

This book is designed as a text-book for amateurs, students, and others

who wish to take up a systematic course of elementary electrical

experiments at home or in school. Full directions are given for.......

_Two Hundred Simple Experiments._

The experiments are discussed by the author, after the student has been

led to form his own opinion about the results obtained and the points

learned.

In selecting the apparatus for the experiments in this book, the author

has kept constantly in mind the fact that the average student will not

buy the expensive pieces usually described in text-books.

The two hundred experiments given can be performed with

simple apparatus; in fact, the student should make at least

a part of his own apparatus, and for the benefit of those

who wish to do this, the author has given, throughout the

work, explanations that will aid in the construction of

certain pieces especially adapted to these experiments. For

those who have the author's "How Two Boys Made Their Own

Electrical Apparatus," constant references have been made to

it as the "Apparatus Book," as this contains full details

for making almost all kinds of simple apparatus needed

in "The Study of Elementary Electricity and Magnetism by

Experiment."

_If you wish to take up a systematic course of experiments--experiments

that may be performed with simple, inexpensive apparatus,--this book

will serve as a valuable guide._

Condensed List of Apparatus

FOR

"The Study of Elementary Electricity and Magnetism by Experiment."

_Number_ 1. Steel Needles; package of twenty-five.--2. Flat Cork.--3.

Candle.--4-15. Annealed Iron Wires; assorted lengths.--16. Horseshoe

Magnet; best quality; English.--17. Iron Filings.--18. Parts for

Compass.--19, 20. Wire Nails; soft steel.--21, 22. Spring Steel; for

bar magnets.--23. Iron Ring.--24. Sifter; for iron filings.--25.

Spring Steel; for flexible magnet.--26, 27. Ebonite Sheets; with

special surface.--28. Ebonite Rod.--29. Ebonite Rod; short.--30.

Flannel Cloth.--31. Tissue Paper.--32. Cotton Thread.--33. Silk

Thread.--34. Support Base.--35. Support Rod.--36. Support Wire.--37.

Wire Swing.--38. Sheet of Glass.--39. Hairpin.--40. Circular

Conductor.--41. Circular Conductor.--42. Electrophorus Cover.--43.

Insulating Table.--44. Insulated Copper Wire.--45. Rubber Band.--46.

Bent Wire Clamps.--47. Cylindrical Conductor.--48. Discharger; for

condenser.--49. Aluminum-Leaf.--50. Wires.

51. Dry Cell.--52. Mercury.--53. Insulated Copper Wire; for

connections.--54. Spring Connectors; two dozen.--55. Parts

for Key.--56. Metal Connecting Plates.--57. Parts for Current

Reverser.--58. Parts for Galvanoscope.--59. Parts for Astatic

Galvanoscope.--60-63. Zinc Strips.--64. Carbon Rod.--65, 66. Glass

Tumblers.--67, 68. Copper Strips.--69. Galvanized Iron Nail.--70,

71. Wooden Cross-Pieces.--72. Brass Screws; one dozen.--73. Porous

Cup.--74. Zinc Rod.--75. Copper Plate.--76. Iron Strip.--77, 78. Lead

Strips.--79. Parts for Resistance Coil.--80. Parts for Wheatstone's

Bridge.--81. German-Silver Wire; Size No. 30.--82. German-Silver Wire;

No. 28.--83--85. Plate Binding-Posts.--86. Copper Sulphate.--87. Copper

Burs; one dozen.--88. Combination Rule.--89. Coil of Wire; on spool

for electromagnet.--90. Coil of Wire; on spool for electromagnet.--91.

Carbon Rod.--92, 93. Soft Iron Cores with Screws.--94. Combined

Base and Yoke.--95. Combination Connecting Plates.--96. Long Iron

Core.--97. Round Bar Magnet, 5 × 3/8 in.--98. Thin Electromagnet.--99.

Degree-Card; for galvanoscope.--100. Scale for Bridge.--101, 102. Soft

Iron Cores with Heads.--103, 104. Flat Bar Magnets; these are 6 × ½ × ¼

in.; highly polished steel; poles marked.--105. Compass.

=_Illustrated Price Catalogue upon Application._=

Electrical Apparatus For Sale

A COMPLETE ELECTRIC AND MAGNETIC CABINET FOR STUDENTS, SCHOOLS AND

AMATEURS. SIX EXTRAORDINARY OFFERS

=This Cabinet of Electrical Experiments= contains three main parts:

(_A_) Apparatus; (_B_) Text-Book; (_C_) Apparatus List.

(_A_) =The Apparatus= furnished consists of one hundred and five

pieces. Over three hundred separate articles are used in making up this

set. Most of it is ready for use when received. Seven pieces, however,

are not assembled; but the parts can be readily finished and put

together. (Sold, also, _all_ pieces assembled.)

(_B_) =The Text-Book=--called "The Study of Elementary Electricity

and Magnetism by Experiment"--gives full directions for two hundred

experiments. (See table of contents, etc.) Price, post-paid, $1.25.

(_C_) =The Apparatus List= is an illustrated book devoted entirely to

this special set of apparatus. Not given with first offer.

_THE APPARATUS IS SIMPLE because the designs and methods of

construction have been worked out with great care._

_THE APPARATUS IS PRACTICAL because it has been designed

for real use in "The Study of Elementary Electricity and

Magnetism by Experiment."_

_THE APPARATUS IS CHEAP because the various parts are

so designed that they can be turned out in quantity by

machinery._

=1st Offer:= Pieces 1 to 50 $1.00

=2d Offer:= Pieces 51 to 105, with part (_C_) 3.50

=3d Offer:= Pieces 1 to 105, with part (_C_) 4.00

=4th Offer:= Complete Cabinet, parts (_A_), (_B_), (_C_) 5.00

=5th Offer:= Apparatus only, all pieces assembled 4.60

=6th Offer:= Complete Cabinet, all pieces assembled 5.60

=_Express charges must be paid by you. Estimates given._=

A "Special Catalogue," pertaining to the above, with complete

price-list, will be mailed upon application.

=THOMAS M. ST. JOHN, 407 West 51st St., New York City=

Fun With Telegraphy

BOOK AND COMPLETE OUTFIT.

[Illustration]

=TELEGRAPHY= is of the greatest importance to all civilized nations,

and upon it depend some of the world's most important enterprises.

Every boy and girl can make practical use of telegraphy in one way or

another, and the time it takes to learn it will be well spent.

=THE OUTFIT.=--Mr. St. John has worked for a number of years to produce

a telegraph outfit that would be simple, cheap, and practical for those

who wish to make a study of telegraphy. After making and experimenting

with nearly one hundred models, many of which were good, he has at last

perfected an instrument so simple, original, and effective that it is

now being made in large quantities.

The sounders are so designed that they will work properly with any dry

cell of ordinary strength, and this is a great advantage for practice

lines. Dry batteries are cheap and clean, and there are no dangers from

acids.

The outfit consists of the following articles, placed in a neat box:

One Book of Instruction, called "Fun With Telegraphy"; one Telegraph

"Key"; one Telegraph "Sounder"; Insulated Copper Wires for connections.

The "key" and "sounder" are mounted, with proper "binding-posts," upon

a base of peculiar construction, which aids in giving a large volume of

sound.

=CONTENTS OF BOOK.=--Telegraphy.--The Outfit.--A Complete Telegraph

Line.--Connections.--The Telegraph Key.--The Sounder.--The Battery.--A

Practice Line.--A Two-instrument Line.--Operation of Line.--The Morse

Telegraph Alphabet.--Aids to Learning Alphabet.--Cautions.--Office

Calls.--Receiving Messages.--Remember.--Extra Parts.

=ABOUT BATTERIES.=--For those who cannot easily secure batteries, we

will furnish small dry cells, post-paid, at 15 cents each, in order to

deliver the outfits complete to our customers. This price barely covers

the total cost to us, postage alone being 6 cents.

_=FUN WITH TELEGRAPHY, including Book, Key, Sounder,

and Wire (no battery), post-paid, 50 cents, by=_

=THOMAS M. ST. JOHN, 848 Ninth Ave., New York=

Tool Sets for Students

The following tool sets have been arranged especially for those who

wish to make use of the designs contained in "How Two Boys Made Their

Own Electrical Apparatus," "Real Electric Toy-Making for Boys,"

"Electric Instrument-Making," etc. It is very poor economy to waste

valuable time and energy in order to save the cost of a few extra tools.

=NOTE.=--Save money by buying your tools in sets. We do not pay express

or freight charges at the special prices below.

=FOR $1.00.=--One _Steel Punch_; round, knurled head.--One light

_Hammer_; polished, nickel-plated, varnished handle.--One _Iron Clamp_;

japanned, 2¼ in.--One _Screw-Driver_; tempered and polished blade,

cherry stained hardwood handle, nickel ferrule.--One _Wrench_; retinned

skeleton frame, gilt adjusting wheel.--One _Awl_; tempered steel

point, turned and stained wood handle, with ferrule.--One _Vise_; full

malleable, nicely retinned, 1-3/8 in. jaws, full malleable screw with

spring.--One pair _Steel Pliers_; 4 in. long, polished tool steel,

unbreakable, best grooved jaw.--One pair of _Shears_; carbonized steel

blades, hardened edge, nickel-plated, heavy brass nut and bolt.--One

_File_; triangular, good steel.--One _File Handle_; good wood, brass

ferrule.--One _Foot Rule_; varnished wood, has English and metric

system.--One _Soldering Set_; contains soldering iron, solder, resin,

sal ammoniac, and directions. One _Center-Punch_; finely tempered steel.

=FOR $2.00.=--All that is contained in the $1.00 set of tools, together

with the following: One pair of _Tinner's Shears_; cut, 2¾ in., cast

iron, hardened, suitable for cutting thin metal.--One _Hollow Handle

Tool Set_; very useful; polished handle holds 10 tools, gimlet,

brad-awls, chisel, etc.--One _Try Square_; 6-in. blue steel blade,

marked in 1/8s, strongly riveted.--One 1-lb. _Hammer_; full size,

polished head, wedged varnished hardwood handle.--One _Hack Saw_; steel

frame, 9½-in. polished steel blade, black enamel handle; very useful.

=FOR $3.50.=--Two _Steel Punches_; different sizes, one solid round,

knurled head, polished; the other, point and head brightly polished,

full nickel, center part knurled.--One _Light Hammer_; polished and

nickel plated, varnished handle.--One regular _Machinist's Hammer_;

ball peen, solid cast steel, with varnished hardwood handle; a

superior article.--Two _Iron Clamps_; one opens 2¼ in., the other

3 in., japanned.--One _Screw-Driver_; tempered and polished blade,

firmly set in cherry stained hardwood handle with nickel ferrule.--One

_Wrench_; retinned, skeleton frame, gilt adjusting wheel.--One _Awl_;

tempered steel blade, ground to point, firmly set in turned and stained

handle with ferrule.--One _Steel Vise_; 2¼-in., jaws, steel screw,

bright polished jaws and handle; a good strong vise.--One pair of

_Steel Pliers_; 6 in. long, bright steel, flat nose, 2 wire-cutters,

practically unbreakable.--One pair of _Shears_; carbonized steel

blades, hardened edges, nickel plated, heavy brass nut and bolt.--One

_File_; triangular and of good steel.--One _File Handle_; good wood,

with brass ferrule.--One _Foot Rule_; varnished wood, has both the

English and metric systems.--One _Soldering Set_; contains soldering

iron, solder, resin, sal ammoniac, and directions; a very handy

article.--One _Center-Punch_; finely tempered steel.--One pair of

_Tinner's Shears_; these are best grade, inlaid steel cutting edges,

polished and tempered, japanned handles; thoroughly reliable.--One

_Hollow Handle Tool Set_; very useful; the polished handle holds 10

tools, gimlet, chisel, brad-awl, etc.--One _Try Square_; 6-in. blue

steel blade, marked both sides in 1/8s, strongly riveted with brass

rivets.--One _Hack Saw_; steel frame, 9½-in. polished steel blade,

black enamel handle; very useful for sawing small pieces of wood.

=FOR $5.00= will be included everything in the $3.50 offer, and the

following: One _Glue-Pot_; medium size, with brush and best wood

glue; inside pot has hinge cover.--One _Ratchet Screw-Driver_; great

improvement over ordinary screw-drivers; well made and useful.--One

_Hand Drill_; frame malleable iron; hollow screw top holding 6 drills;

bores from 1-16 to 3-16-in. holes; solid gear teeth; 3-jawed nickel

plated chuck; a superior tool, and almost a necessity.

=GIVE THE BOY A SET OF TOOLS=

=THOMAS M. ST. JOHN, 848 Ninth Ave., New York=

REAL ELECTRIC TOY-MAKING FOR BOYS

_By_ THOMAS M. ST. JOHN, Met. E.

This book contains 140 pages and over one hundred

original drawings, diagrams, and full-page plates.

It measures 5 x 7½ in., and is bound in cloth.

Price, post-paid, $1.00

=CONTENTS:= _Chapter_ I. Toys Operated by Permanent Magnets.--II.

Toys Operated by Static Electricity.--III. Making Electromagnets for

Toys.--IV. Electric Batteries.--V. Circuits and Connections.--VI. Toys

Operated by Electromagnets. VII. Making Solenoids for Toys.--VIII.

Toys Operated by Solenoids.--IX. Electric Motors.--X. Power,

Speed, and Gearing.--XI. Shafting and Bearings.--XII. Pulleys and

Winding-Drums.--XIII. Belts and Cables.--XIV. Toys Operated by

Electric Motors.--XV. Miscellaneous Electric Toys.--XVI. Tools.--XVII.

Materials.--XVIII. Various Aids to Construction.

While planning this book, Mr. St. John definitely decided that he would

not fill it with descriptions of complicated, machine-made instruments

and apparatus, under the name of "Toy-Making," for it is just as

impossible for most boys to get the parts for such things as it is

for them to do the required machine work even after they have the raw

materials.

Great care has been taken in designing the toys which are described

in this book, in order to make them so simple that any boy of average

ability can construct them out of ordinary materials. The author can

personally guarantee the designs, for there is no guesswork about

them. Every toy was made, changed, and experimented with until it was

as simple as possible; the drawings were then made from the perfected

models.

As the result of the enormous amount of work and experimenting which

were required to originate and perfect so many new models, the author

feels that this book may be truly called "Real Electric Toy-Making for

Boys."

=Every Boy Should Make Electrical Toys.=

The Electric Shooting Game>

A MOST ORIGINAL AND FASCINATING GAME PATENT APPLIED FOR AND COPYRIGHTED

[Illustration]

_=SHOOTING BY ELECTRICITY=_

=The Electric Shooting Game= is an entirely new idea, and one that

brings into use that most mysterious something--_electricity_. The

game is so simple that small children can play it, and as there are

no batteries, acids, or liquids of any kind, there is absolutely no

danger. The electricity is of such a nature that it is perfectly

harmless--but very active.

The "_game-preserve_" is neat and attractive, being printed in colors,

and the birds and animals are well worth hunting. Each has a fixed

value--and some of them must not be shot at all--so there is ample

opportunity for a display of skill in bringing down those which count

most.

"_Electric bullets_" are actually shot from the "_electric gun_" by

electricity. This instructive game will furnish a vast amount of

amusement to all.

_=The "Game-Preserve,"--the "Electric Gun,"--the

"Shooting-Box,"--the "Electric Bullets,"--in fact, the

entire electrical outfit, together with complete illustrated

directions, will be sent in a neat box, Post-Paid, upon

receipt of 50 cents, by=_

=THOMAS M. ST. JOHN, 848 Ninth Ave., New York=

* * * * *

Transcriber's note:

Obvious punctuation errors were corrected.

Page 46, "turnnd" changed to "turned" (be turned to 1)

Page 66, word "a" added to text (in a glass jar)

Things a Boy Should Know About Electricity Second Edition · 第 16 / 16 章