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Electricity for boys

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Title:ElectricityforBoys
Author:J.S.Zerbe
ReleaseDate:September25,2007[EBook#22766]
Language:English

***STARTOFTHISPROJECTGUTENBERGEBOOKELECTRICITYFORBOYS***

ProducedbyJoeLongoandtheOnlineDistributed
ProofreadingTeamathttp://www.pgdp.net


WARNING:Thisbookofonehundredyearsago
describes
experimentswhicharetoodangeroustoattemptby
either

adultsorchildren.Itispublishedforhistorical
interestonly.

THE"HOW-TO-DO-IT"BOOKS


ELECTRICITYFORBOYS
Fig.1.WORKBENCH
Fig.1.WORKBENCH


THE "HOW-TO-DO-IT"
BOOKS

ELECTRICITYFOR
BOYS
A working guide, in the successive
steps of electricity, described in
simpleterms
WITH MANY ORIGINAL
ILLUSTRATIONS

ByJ.S.ZERBE,M.E.
AUTHOROF
CARPENTRYFORBOYS
PRACTICALMECHANICSFOR
BOYS

Printer'sMark:NYBC/Windmill
THENEWYORKBOOKCOMPANY
NEW YORK

COPYRIGHT,1914,BY
THENEWYORKBOOKCOMPANY


p.i

CONTENTS
INTRODUCTORY




Page1


I.

ELECTRICITYCONSIDERED.BRIEFHISTORICAL
EVENTS

Page5

The Study of Electricity. First Historical
Accounts. Bottling Electricity. Discovery of
Galvanic Electricity. Electro-motive Force.
Measuring Instruments. Rapidity of Modern
Progress. How to Acquire the Vast Knowledge.
TheMeansEmployed.
II. WHATTOOLSANDAPPARATUSARENEEDED

Page11

PreparingtheWorkshop.UsesofOurWorkshop.
What to Build. What to Learn. Uses of the
ElectricalDevices.Tools.Magnet-windingReel.
III. MAGNETS,COILS,ARMATURES,ETC.

Page18

TheTwoKindsofMagnets.PermanentMagnets.
Electro-Magnets. Magnetism. Materials for
Magnets. Non-magnetic Material. Action of a
Second Magnet. What North and South Pole
Mean. Repulsion and Attraction. Positives and
Negatives.MagneticLinesofForce.TheEarthas
a Magnet. Why the Compass Points North and
South. Peculiarity of a Magnet. Action of the
Electro-Magnet. Exterior Magnetic Influence
Around a Wires Carrying a Current. Parallel
Wires.
IV.

FRICTIONAL,VOLTAICORGALVANICAND
ELECTRO-MAGNETICELECTRICITY

Page29

p.ii


Three Electrical Sources. Frictional Electricity.
L e y d e nJar. Voltaic or Galvanic Electricity.
Voltaic Pile; How Made. Plus and Minus Signs.
The Common Primary Cell. Battery Resistance.
Electrolyte and Current. Electro-magnetic
Electricity. Magnetic Radiation. Different Kinds
of Dynamos. Direct Current Dynamos. Simple
MagnetConstruction.HowtoWind.TheDynamo
Fields. The Armature. Armature Windings.
Mounting the Armature. The Commutator.
Commutator Brushes. Dynamo Windings. The
Field. Series-wound Field. Shunt-wound.
Compound-wound.
V. HOWTODETECTANDMEASUREELECTRICITY

Page49

Measuring Instruments. The Detector. Direction
of Current. Simple Current Detector. How to
Place the Detector. Different Ways to Measure a
Current. The Sulphuric Acid Voltameter. The
Copper Voltameter. The Galvanoscope Electromagnetic Method. The Calorimeter. The Light
Method. The Preferred Method. How to Make a
Sulphuric Acid Voltameter. How to Make a
Copper Voltameter. Objections to the
Calorimeter.
VI. VOLTS,AMPERES,OHMSANDWATTS

Page60

Understanding Terms. Intensity and Quantity.
Voltage. Amperage Meaning of Watts and
Kilowatt. A Standard of Measurement. The
Ampere Standard. The Voltage Standard. The
Ohm.CalculatingtheVoltage.
PUSHBUTTONS,SWITCHES,ANNUNCIATORS,


VII. BELLSANDLIKEAPPARATUS

Page65

Simple Switches. A Two-Pole Switch. DoublePole Switch. Sliding Switch. Reversing Switch.
Push Buttons.Electric Bells. How Made. How
Operated. Annunciators. Burglar Alarm. Wire
Circuiting.CircuitingSystemwithTwoBellsand
Push Buttons. The Push Buttons, Annunciators
andBells.WiringUpaHouse.
VIII.

ACCUMULATORS,STORAGEORSECONDARY
BATTERIES

Page82

Storing Up Electricity. The Accumulator.
Accumulator Plates. The Grid. The Negative
Pole. Connecting Up the Plates. Charging the
Cells.TheInitialCharge.TheChargingCurrent.
IX. THETELEGRAPH

Page90

Mechanism in Telegraph Circuit. The Sending
Key. The Sounder. Connecting Up the Key and
Sounder. Two Stations in Circuit. The Double
Click. Illustrating the Dot and the Dash. The
MorseTelegraphCode.ExampleinUse.
X. HIGH-TENSIONAPPARATUS,CONDENSERS,ETC.

Page98

Induction. Low and High Tension. Elastic
Property of Electricity. The Condenser.
ConnectingupaCondenser.TheInterrupter.Uses
ofHigh-tensionCoils.
XI. WIRELESSTELEGRAPHY

Page104

Telegraphing Without Wires. Surging Character
of High-tension Currents. The Coherer. How
Made. The Decoherer. The Sending Apparatus.


The Receiving Apparatus. How the Circuits are
Formed.
XII. THETELEPHONE

Page110

Vibrations. The Acoustic Telephone. Sound
Waves.Hearing Electricity. The Diaphragm in a
Magnetic Field. A Simple Telephone Circuit.
How to Make a Telephone. Telephone
Connections. Complete Installation. The
Microphone.LightContactPoints.HowtoMake
a Microphone. Microphone, the Father of the
Transmitter. Automatic Cut-outs for Telephones.
CompleteCircuitingwithTransmitters.
XIII.

ELECTROLYSIS,WATERPURIFICATION,
ELECTROPLATING

Page123

Decomposing Liquids. Making Hydrogen and
Oxygen. Purifying Water. Rust. Oxygen as a
Purifier.CompositionofWater.CommonAirNot
a Good Purifier. Pure Oxygen a Water Purifier.
The Use of Hydrogen in Purification.Aluminum
Electrodes. Electric Hand Purifier. Purification
and Separation of Metals. Electroplating. Plating
IronwithCopper.DirectionofCurrent.
XIV. ELECTRICHEATING.THERMO-ELECTRICITY

Page135

Generating Heat in a Wire. Resistance of
Substances. Signs of Connectors. Comparison of
Metals. A Simple Electric Heater. How to
Arrange for Quantity of Current Used. An
Electric Iron. Thermo-Electricity Converting
Heat Directly into Electricity Metals. Electric,
Positive,Negative.Thermo-electricCoupler.


XV.

ALTERNATINGCURRENTS,CHOKINGCOIL,
TRANSFORMER

Page145

Direct Current. Alternating Current. The
Magnetic Field. Action of a Magnetized Wire.
The Movement of a Current in a Charged Wire.
Current Reversing Itself. Self-Induction. Brushes
inaDirectCurrentDynamo:Alternating,Positive
and Negative Poles. How anAlternating Current
Dynamo is Made. The Windings. The Armature
Wires.ChokingCoils.TheTransformer.Howthe
Voltage is Determined.Voltage andAmperage in
Transformers.
XVI. ELECTRICLIGHTING

Page161

Earlyconditions.Fuels.ReversibilityofDynamo.
Electric arc. Mechanism to maintain the arc.
Resistance coil. Parallel carbons for making arc.
Series current. Incandescent system. Multiple
circuit. Subdivision of electric light. The
filament. The glass bulb. Metallic filaments.
Vapor lamps. Directions for improvements. Heat
in electric lighting. Curious superstitions
concerning electricity. Magnetism. Amber.
Discovery of the properties of a magnet.
Electricity in mountain regions. Early beliefs as
to magnetism and electricity. The lightning rod.
Protests against using it. Pliny's explanation of
electricity.
XVII.

POWER,ANDVARIOUSOTHERELECTRICAL
MANIFESTATIONS

Page175

Early beliefs concerning the dynamo.
Experiments with magnets. Physical action of


dynamo and motor. Electrical influence in
windings. Comparing motor and dynamo. How
thecurrentactsinadynamo.Itsforceinamotor.
Loss in power transmission. The four ways in
which power is dissipated. Disadvantages of
electric power. Its advantages. Transmission of
energy. High voltages. The transformer. Stepdowntransformers.Electricfurnaces.Weldingby
electricity. Merging the particles of the joined
ends.
XVIII. X-RAY,RADIUMANDTHELIKE

Page184

The camera and the eye. Actinic rays. Hertzian
waves. High-tension apparatus. Vacuum tubes.
Character of the ultra-violet rays. How
distinguished. The infra-red rays. Their uses. Xrays not capable of reflection. Not subject to
refraction. Transmission through opaque
substances.Reducingratesofvibration.Radium.
Radio-activity.
Radio-active
materials.
Pitchblende. A new form of energy. Electrical
source.Healingpower.Problemsforscientists.
GLOSSARYOFWORDSUSEDINTHETEXT
INDEX

Page189
Page207


p.vii


LISTOFILLUSTRATIONS
1. Workbench

2. Topofmagnet-windingreel
3. Sideofmagnet-windingreel
4. Journalblock
5. Plainmagnetbar
6. Severedmagnet
7. Reversedmagnets
8. Horseshoemagnet
9. Earth'smagneticlines
10. Twopermanentmagnets
11. Magnetsinearth'smagneticfield
12. Armaturesformagnets
13. Magnetizedfield
14. Magnetizedbar
15. Directionofcurrent
16. Directionofinductioncurrent
17. Frictional-electricitymachine
18. Leydenjar
19. Galvanicelectricity.Crownofcups
20. Voltaicelectricity
21. Primarybattery
22. Dynamofieldandpolepiece
23. Baseandfieldsassembled
24. Detailsofthearmature,core
25. Detailsofthearmature,body
26. ArmatureJournals
27. Commutator
28. Endviewofarmature,mounted

Frontispiece
PAGE
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p.viii


29. Topviewofarmatureonbase
30. Fieldwinding
31. Series-wound
32. Shunt-wound
33. Compound-wound
34. Compassmagnet,swingtotheright
35. Magneticcompass
36. Magnet,swingtotheleft
37. Indicatingdirectionofcurrent
38. Thebridgeofthedetector
39. Detailsofdetector
40. Cross-sectionofdetector
41. Acidvoltameter
42. Coppervoltameter
43. Two-poleswitch
44. Double-poleswitch
45. Slidingswitch
46. Rheostatformofswitch
47. Reversingswitch
48. Pushbutton
49. Electricbell
50. Armatureofelectricbell
51. Verticalsectionofannunciator
52. Frontviewofannunciator
53. Horizontalsectionofannunciator
54. Frontplateofannunciator
55. Alarmswitchonwindow
56. Burglaralarmonwindow
57. Burglaralarmcontact
58. Neutralpositionofcontact
59. Circuitingforelectricbell
60. Annunciatorsincircuit
61. Wiringsystemforahouse

45
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62. Accumulatorgrids

83

63. Assemblageofaccumulatorgrids
64. Connectingupstoragebatteryinseries
65. Parallelseries
66. Chargingcircuit
67. Telegraphsendingkey
68. Telegraphsounder
69. Atelegraphcircuit
70. Inductioncoilandcircuit
71. Illustratingelasticity
72. Condenser
73. High-tensioncircuit
74. Currentinterrupter
75. Wireless-telegraphycoherer
76. Wirelesssending-apparatus
77. Wirelessreceiving-apparatus
78. Acoustictelephone
79. Illustratingvibrations
80. Themagneticfield
81. Sectionoftelephonereceiver
82. Themagnetandreceiverhead
83. Simpletelephoneconnection
84. Telephonestationsincircuit
85. Illustratinglightcontactpoints
86. Themicrophone
87. Thetransmitter
88. Completetelephonecircuit
89. Deviceformakinghydrogenandoxygen
90. Electric-waterpurifier
91. Portableelectricpurifier
92. Sectionofpositiveplate
93. Sectionofnegativeplate
94. Positiveandnegativeinposition

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121
124
127
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130
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95. Formoftheinsulator
96. Simpleelectricheater
97. Sideviewofresistancedevice
98. Topviewofresistancedevice
99. Planviewofelectriciron
100. Sectionofelectriciron
101. Thermo-electriccouple
102. Cuttingamagneticfield
103. Alternations,firstposition
104. Alternations,secondposition
105. Alternations,thirdposition
106. Alternations,fourthposition
107. Increasingalternations,firstview
108. Increasingalternations,secondview
109. Connectionofalternatingdynamoarmature
110. Directcurrentdynamo
111. Circuitwiresindirectcurrentdynamo
112. Alternatingpolaritylines
113. Alternatingcurrentdynamo
114. Chokingcoil
115. Atransformer
116. Parallelcarbons
117. Arc-lightingcircuit
118. Interruptedconductor
119. Incandescentcircuit
120. Magneticactionindynamo,1st
121. Magneticactionindynamo,2d
122. Magneticactionindynamo,3d
123. Magneticactionindynamo,4th
124. Magneticactioninmotor,1st
125. Magneticactioninmotor,2d
126. Magneticactioninmotor,3d
127. Magneticactioninmotor,4th

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p.1


INTRODUCTORY
Electricity,likeeveryscience,presentstwophasestothestudent,onebelonging
to a theoretical knowledge, and the other which pertains to the practical
applicationofthatknowledge.Theboyisdirectlyinterestedinthepracticaluse
whichhecanmakeofthiswonderfulphenomenoninnature.
Itis,inreality,themostsuccessfulavenuebywhichhemayobtainthetheory,
forhelearnstheabstractmorereadilyfromconcreteexamples.
Itisanartinwhichshoppracticeisagreatereducatorthancanbepossiblewith
books.Boysarenot,generally,inclinedtospeculateortheorizeonphenomena
apart fromthe workitself;butonceputthemintocontactwiththemechanism
itself,letthembecomealivingpartofit,andtheywillcommencetoreasonand
thinkforthemselves.
Itwouldbeadry,dullanduninterestingthingtotellaboythatelectricitycanbe
p.2
generatedbyrivetingtogethertwopiecesofdissimilarmetals,andapplyingheat
to the juncture. But put into his hands the metals, and set him to perform the
actualworkofrivetingthemetalstogether,thenwiringuptheendsofthemetals,
heating them, and, with a galvanometer, watching for results, it will at once
make him see something in the experiment which never occurred when the
abstracttheorywaspropounded.
He will inquire first what metals should be used to get the best results, and
finally, he will speculate as to the reasons for the phenomena. When he learns
that all metals are positive-negative or negative-positive to each other, he has
grasped a new idea in the realm of knowledge, which he unconsciously traces
back still further, only to learn that he has entered a field which relates to the
constitution of matter itself. As he follows the subject through its various
channels he will learn that there is a common source of all things; a
manifestationcommontoallmatter,andthatallsubstancesinnaturearelinked
togetherinamostwonderfulway.
Animpulsemustbegiventoaboy'straining.Thetimeispastfortherule-androte method. The rule can be learned better by a manual application than by
committingasentencetomemory.
p.3


In the preparation of this book, therefore, I have made practice and work the
predominatingfactors.Ithasbeenmyaimtosuggestthebestforminwhichto
dothethingsinapracticalway,andfromthatwork,astheboycarriesitout,to
deducecertainlawsanddeveloptheprincipleswhichunderliethem.Whereverit
isdeemedpossibletodoso,itisplannedtohavetheboymakethesediscoveries
forhimself,soastoencouragehimtobecomeathinkerandareasonerinsteadof
ameremachine.
A boy does not develop into a philosopher or a scientist through being told he
mustlearntheprinciplesofthisteaching,orthefundamentalsofthatschoolof
reasoning.Hewillunconsciouslyimbibethespiritandthewillingnessifwebut
place before him the tools by which he may build even the simple machinery
thatdisplaysthevariouselectricalmanifestations.


p.5


CHAPTERI
THESTUDYOFELECTRICITY.HISTORICAL
Thereisnostudysoprofoundaselectricity.Itisamarveltothescientistaswell
as to the novice. It is simple in its manifestations, but most complex in its
organization and in its ramifications. It has been shown that light, heat,
magnetism and electricity are the same, but that they differ merely in their
modesofmotion.
FIRSTHISTORICALACCOUNT.—Thefirsthistoricalaccountofelectricitydatesback
to600yearsB.C.ThalesofMiletuswasthefirsttodescribethepropertiesof
amber, which, when rubbed, attracted and repelled light bodies. The ancients
also described what was probably tourmaline, a mineral which has the same
qualities.Thetorpedo,afishwhichhasthepowerofemittingelectricimpulses,
wasknowninveryearlytimes.
From that period down to about the year 1600 no accounts of any historical
valuehavebeengiven.Dr.Gilbert,ofEngland,madeanumberofresearchesat
thattime,principallywithamberandothermaterials,andBoyle,in1650,made
numerousexperimentswithfrictionalelectricity.
Sir Isaac Newton also took up the subject at about the same period. Inp.61705
Hawksbee made numerous experiments; also Gray, in 1720, and a Welshman,
Dufay, at about the same time. The Germans, from 1740 to 1780, made many
experiments.In1740,atLeyden,wasdiscoveredthejarwhichbearsthatname.
Beforethattime,allexperimentsbeganandendedwithfrictionalelectricity.
The first attempt to "bottle" electricity was attempted by Muschenbrœck, at
Leyden,whoconceivedtheideathatelectricityinmaterialsmightberetainedby
surroundingthemwithbodieswhichdidnotconductthecurrent.Heelectrified
some water in a jar, and communication having been established between the
water and the prime conductor, his assistant, who was holding the bottle, on
tryingtodisengagethecommunicatingwire,receivedasuddenshock.
In1747SirWilliamWatsonfiredgunpowderbyanelectricspark,and,lateron,
apartyfromtheRoyalSociety,inconjunctionwithWatson,conductedaseries
of experiments to determine the velocity of the electric fluid, as it was then


termed.
BenjaminFranklin,in1750,showedthatlightningwaselectricity,andlateron
madehisinterestingexperimentswiththekiteandthekey.
DISCOVERING GALVANIC ELECTRICITY.—The great discovery of Galvani, in 1790,
ledtotherecognitionofanewelementinelectricity,calledgalvanicorvoltaic
(named after the experimenter, Volta), and now known to be identical with
frictional electricity. In 1805 Poisson was the first to analyze electricity; and
when Œrsted of Copenhagen, in 1820, discovered the magnetic action of
electricity, it offered a great stimulus to the science, and paved the way for
investigationinanewdirection.Amperewasthefirsttodeveloptheideathata
motororadynamocouldbemade operative by means ofthe electro-magnetic
current;andFaraday,about1830,discoveredelectro-magneticrotation.
ELECTRO-MAGNETICFORCE.—Fromthistimeontheknowledgeofelectricitygrew
withamazingrapidity.Ohm'sdefinitionofelectro-motiveforce,currentstrength
and resistance eventuated into Ohm's law. Thomson greatly simplified the
galvanometer, and Wheatstone invented the rheostat, a means of measuring
resistance,about1850.ThenprimarybatterieswerebroughtforwardbyDaniels,
Grove, Bunsen and Thomson, and electrolysis by Faraday. Then came the
instruments of precision—the electrometer, the resistance bridge, the ammeter,
thevoltmeter—alloftheutmostvalueinthescience.
MEASURINGINSTRUMENTS.—Theperfectionofmeasuringinstrumentsdidmoreto
advanceelectricitythanalmostanyotherfieldofendeavor;sothatafter1875the
inventors took up the subject, and by their energy developed and put into
practical operation a most wonderful array of mechanism, which has become
valuableintheserviceofmaninalmosteveryfieldofhumanactivity.
RAPIDITYOFMODERNPROGRESS.—Thisbriefhistoryisgivenmerelytoshowwhat
wondershavebeenaccomplishedinafewyears.Theartisreallylessthanfifty
yearsold,andyetsorapidlyhasitgoneforwardthatitisnotatallsurprisingto
heartheremark,thattheendofthewondershasbeenreached.LessthantwentyfiveyearsagoahighofficialoftheUnitedStatesPatentOfficestatedthatitwas
probable the end of electrical research had been reached. The most wonderful
developments have been made since that time; and now, as in the past, one
discoveryisbutthepreludetoanotherstillmoreremarkable.Wearebeginning
tolearnthatweareonlyonthethresholdofthatstorehouseinwhichnaturehas
lockedhersecrets,andthatthereisnolimittohumaningenuity.


HOW TO ACQUIRE THE VAST KNOWLEDGE.—As the boy, with his limited vision,
surveys this vast accumulation of tools, instruments and machinery, and sees
whathasbeenandisnowbeingaccomplished,itisnottobewonderedatthathe
should enter the field with timidity. In his mind the great question is, how to
acquiretheknowledge.Thereissomuchtolearn.Howcanitbeaccomplished?
The answer to this is, that the student of to-day has the advantage of the
knowledgeofallwhohavegonebefore;andnowthepertinentthingistoacquire
thatknowledge.
THEMEANSEMPLOYED.—Thisbringsusdefinitelydowntoanexaminationofthe
means that we shall employ to instil this knowledge, so that it may become a
permanentassettothestudent'sstoreofinformation.
The most significant thing in the history of electrical development is the
knowledge that of all the great scientists not one of them ever added any
knowledge to the science on purely speculative reasoning. All of them were
experimenters. They practically applied and developed their theories in the
laboratoryortheworkshop.Thenaturalinferenceis,therefore,thattheboywho
startsouttoacquireaknowledgeofelectricity,mustnotonlytheorize,butthat
heshall,primarily,conducttheexperiments,andtherebyacquiretheinformation
in a practical way, one example of which will make a more lasting impression
thanpagesofdrytext
Throughout these pages, therefore, I shall, as briefly as possible, point out the
theoriesinvolved,asafoundationforthework,andthenillustratethestructural
typesorsamples;andtheworkissoarrangedthatwhatisdoneto-dayismerely
apreludeorstepping-stonetothenextphaseoftheart.Inreality,weshalltravel,
toaconsiderableextent,thecoursewhichthegreatinvestigatorsfollowedwhen
they were groping for the facts and discovering the great manifestations in
nature.


p.11


CHAPTERIIToC
WHATTOOLSANDAPPARATUSARENEEDED
PREPARING THE WORKSHOP.—Before commencing actual experiments we should
preparetheworkshopandtools.Sincewearegoingintothisworkaspioneers,
we shall have to be dependent upon our own efforts for the production of the
electricalapparatus,soastobeable,withourhome-madefactory,toprovidethe
power, the heat and the electricity. Then, finding we are successful in these
enterprises,wemaylookforwardfor"moreworldstoconquer."
Bythistimeourneighborswillbecomeinterestedinandsolicitworkfromus.
USES OF OUR WORKSHOPS.—They may want us to test batteries, and it then
becomesnecessarytoconstructmechanismtodetectandmeasureelectricity;to
installnewandimprovedapparatus;andtoputinandconnectupelectricbellsin
their houses, as well as burglar alarms. To meet the requirements, we put in a
telegraph line, having learned, as well as we are able, how they are made and
operated. But we find the telegraph too slow and altogether unsuited for our
p.12
purposes,aswellasfortheusesoftheneighborhood,soweconcludetoputina
telephonesystem.
WHAT TOBUILD.—Itisnecessary,therefore,tocommencerightatthebottomto
build a telephone, a transmitter, a receiver and a switch-board for our system.
From the telephone we soon see the desirability of getting into touch with the
greatoutsideworld,andwirelesstelegraphyabsorbsourtimeandenergies.
Butaswelearn moreand moreofthewonderfulthingselectricitywilldo,we
are brought into contact with problems which directly interest the home.
Sanitationattractsourattention.Whycannotelectricityactasanagenttopurify
ourdrinkingwater,tosterilizesewageandtoarrestoffensiveodors?Wemust,
therefore,learnsomethingaboutthesubjectofelectrolysis.
WHATTOLEARN.—Thedecompositionofwaterisnottheonlythingthatweshall
describe pertaining to this subject. We go a step further, and find that we can
decomposemetalsaswellasliquids,andthatwecanmakeapuremetaloutof
animpureone,aswellasmakethefoulestwaterpure.Butweshallalso,inthe
course ofourexperiments, findthatacheapmetalcanbecoatedwithacostly
p.13


onebymeansofelectricity—thatwecanelectroplatebyelectrolysis.
USES OF THEELECTRICALDEVICES.—Whileallthisisprogressingandourfactory
isturningoutanamazingvarietyofusefularticles,weareledtoinquireintothe
usestowhichwemaydevoteoursurpluselectricity.Thecurrentmaybediverted
forboilingwater;forweldingmetals;forheatingsad-irons,aswellasforother
purposeswhicharedailyrequired.
TOOLS.—Todothesethingstoolsarenecessary,andforthepresenttheyshould
notbeexpensive.Asmall,rigidlybuiltbenchisthefirstrequirement.Thismay
bemade,asshowninFig.1,ofthree2-inchplanks,each10incheswideand6
feetlong,mountedonlegs36inchesinheight.Inthefrontpartarethreedrawers
foryourmaterial,orthesmalloddsandends,aswellasforsuchlittletoolsas
you may accumulate. Then you will need a small vise, say, with a 2-inch jaw,
and you will also require a hand reel for winding magnets. This will be fully
describedhereafter.
You can also, probably, get a small, cheap anvil, which will be of the greatest
service in your work. It should be mounted close up to the work bench. Two
small hammers, one with an A-shaped peon, and the other with a round peon,
shouldbeselected,andalsoaplaneandasmallwoodsawwithfineteeth.Abit
stock, or a ratchet drill, if you can afford it, with a variety of small drills; two
woodchisels,sayof⅜-inchand¾-inchwidths;smallcoldchisels;hacksaw,10inchblade;smallironsquare;pairofdividers;tinshears;wirecutters;2pairsof
pliers,oneflatandtheotherround-nosed;2awls,centeringpunch,wirecutters,
and,finally,solderingtools.


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