DuringthefirstthreemonthsofoperatingthePearlStreetstationlightwassuppliedtocustomerswith-
outcharge。Edisonhadperfectconfidenceinhismeters，andalsointheultimatejudgmentofthepublicastothesuperiorityoftheincandescentelectriclightasagainstotherilluminants。Herealized，however，thatinthebeginningoftheoperationofanentirelynovelplanttherewasampleopportunityforunexpectedcontingencies，althoughthegreatestcarehadbeenexercisedtomakeeverythingasperfectaspossible。Mechanicaldefectsorotherunforeseentroublesinanypartoftheplantorundergroundsystemmightariseandcausetemporarystoppagesofoperation，thusgivinggroundsforuncertaintywhichwouldcreateafeelingofpublicdistrustinthepermanenceofthesupplyoflight。
Astothekindofmishapthatwaswonttooccur，Edisontellsthefollowingstory：“Oneafternoon，afterourPearlStreetstationstarted，apolicemanrushedinandtoldustosendanelectricianatonceuptothecornerofAnnandNassaustreets——sometrouble。AnothermanandIwentup。Wefoundanimmensecrowdofmenandboysthereandintheadjoiningstreets——aperfectjam。Therewasaleakinoneofourjunction-boxes，andonaccountofthecellarsextendingunderthestreet，thetopsoilhadbecomeinsulated。Hence，bymeansofthisleakpowerfulcurrentswerepassingthroughthisthinlayerofmoistearth。Whenahorsewenttopassoverithewouldgetaverysevereshock。WhenI
arrivedIsawcomingalongthestreetaragmanwithadilapidatedoldhorse，andoneoftheboystoldhimtogooverontheothersideoftheroad——whichwastheplacewherethecurrentleaked。Whentherag-
manheardthishetookthatsideatonce。Themomentthehorsestrucktheelectrifiedsoilhestoodstraightupintheair，andthenrearedagain；andthecrowdyelled，thepolicemanyelled；andthehorsestartedtorunaway。Thiscontinueduntilthecrowdgotsoseriousthatthepolicemanhadtoclearitout；
andwewerenotifiedtocutthecurrentoff。Wegotagangofmen，cutthecurrentoffforseveraljunction-
boxes，andfixedtheleak。Onemanwhohadseenitcametomenextdayandwantedmetoputinapparatusforhimataplacewheretheysoldhorses。Hesaidhecouldmakeafortunewithit，becausehecouldgetoldnagsinthereandmakethemactlikethoroughbreds。“
Sowellhadtheworkbeenplannedandexecuted，however，thatnothinghappenedtohinderthecontinuousworkingofthestationandthesupplyoflighttocustomers。HenceitwasdecidedinDecember，1882，tobeginchargingapricefortheservice，and，accordingly，Edisonelectrolyticmeterswereinstalledonthepremisesofeachcustomerthenconnected。
Thefirstbillforlighting，baseduponthereadingofoneofthesemeters，amountedto$50。40，andwascollectedonJanuary18，1883，fromtheAnsoniaBrassandCopperCompany，17and19CliffStreet。Generallyspeaking，customersfoundthattheirbillscomparedfairlywithgasbillsforcorrespondingmonthswherethesameamountoflightwasused，andtheypaidpromptlyandcheerfully，withemphaticencomiumsofthenewlight。DuringNovember，1883，alittleoveroneyearafterthestationwasstarted，billsforlightingamountingtoover$9000
werecollected。
AninterestingstoryofmeterexperienceinthefirstfewmonthsofoperationofthePearlStreetstationistoldbyoneofthe“boys“whowastheninpositiontoknowthefacts；“Mr。J。P。Morgan，whosefirmwasoneofthefirstcustomers，expressedtoMr。Edisonsomedoubtastotheaccuracyofthemeter。Thelatter，firmlyconvincedofitscorrectness，suggestedastricttestbyhavingsomecardsprintedandhungoneachfixtureatMr。Morgan\'splace。Onthesecardswastobenotedthenumberoflampsinthefixture，andthetimetheywereturnedonandoffeachdayforamonth。Attheendofthattimethelamp-hoursweretobeaddedtogetherbyoneoftheclerksandfiguredonabasisofadefiniteamountperlamp-hour，andcomparedwiththebillthatwouldberenderedbythestationforthecorrespondingperiod。
Theresultsofthefirstmonth\'stestshowedanapparentoverchargebytheEdisoncompany。Mr。Morganwasexultant，whileMr。Edisonwasstillconfidentandsuggestedacontinuationofthetest。
Anothermonth\'strialshowedsomewhatsimilarresults。
Mr。Edisonwasalittledisturbed，butinsistedthattherewasamistakesomewhere。HewentdowntoDrexel，Morgan&Company\'sofficetoinvestigate，and，afterlookingaround，askedwhentheofficewascleanedout。Hewastolditwasdoneatnightbythejanitor，whowassentfor，anduponbeinginterrogatedastowhatlightheused，saidthatheturnedonacentralfixturecontainingabouttenlights。Itcameoutthathehadmadenorecordofthetimetheselightswereinuse。Hewastoldtodosoinfuture，andanothermonth\'stestwasmade。Oncomparisonwiththecompany\'sbill，renderedonthemeter-reading，themetercamewithinafewcentsoftheamountcomputedfromthecardrecords，andMr。Morganwascompletelysatisfiedoftheaccuracyofthemeter。“
Itisastrangebutnotextraordinarycommentaryontheperversityofhumannatureandthelackofcorrectobservation，tonotethatevenafterthePearlStreetstationhadbeeninactualoperationtwenty-
fourhoursadayfornearlythreemonths，thereshouldstillremainanattitudeof“can\'tbedone。“
Thatsuchascepticismstillobtainedisevidencedbythepublicprintsoftheperiod。Edison\'selectric-
lightsystemandhisbroadclaimswerefreelydiscussedandanimadverteduponattheverytimehewasdemonstratingtheirsuccessfulapplication。Toshowsomeofthefeelingatthetime，wereproducethefollowingletter，whichappearedNovember29，1882：
“TotheEditoroftheSun：
“SIR，——InreadingthediscussionsrelativetothePearlStreetstationoftheEdisonlight，Ihavenotedthatwhileitisclaimedthatthereisscarcelyanylossfromleakageofcurrent，nothingissaidaboutthelossduetotheresistanceofthelongcircuits。Iaminformedthatthisisthesecretofthefailuretoproducewiththepowerinpositionasufficientamountofcurrenttorunallthelampsthathavebeenputup，andthatwhilesix，andevenseven，lightstothehorse-powermaybeproducedfromanisolatedplant，theresistanceofthelongundergroundwiresreducesthisresultintheabovecasetolessthanthreelightstothehorse-power，thusmakingthecostofproductiongreatlyinexcessofgas。CantheEdisoncompanyexplainthis？
“INVESTIGATOR。“
Thiswasoneofthemanyanonymouslettersthathadbeenwrittentothenewspapersonthesubject，andthefollowingreplybytheEdisoncompanywasprintedDecember3，1882：
“TotheEditoroftheSun：
“SIR，——`Investigator\'inWednesday\'sSun，saysthattheEdisoncompanyistroubledatitsPearlStreetstationwitha`lossofcurrent，duetotheresistanceofthelongcircuits\'；alsothat，whereasEdisongets`sixorevensevenlightstothehorse-powerinisolatedplants，theresistanceofthelongundergroundwiresreducesthatresultinthePearlStreetstationtolessthanthreelightstothehorse-power。\'Bothofthesestatementsarefalse。
Asregardslossduetoresistance，thereisawell-knownlawfordeterminingit，basedonOhm\'slaw。Byuseofthatlawweknewinadvance，thatistosay，whentheoriginalplansforthestationweredrawn，justwhatthislosswouldbe，preciselythesameasamechanicalengineerwhenconstructingamillwithlonglinesofshaftingcanforecastthelossofpowerduetofriction。ThepracticalresultinthePearlStreetstationhasfullydemonstratedthecorrectnessofourestimatethusmadeinadvance。Asregardsourgettingonlythreelightsperhorse-power，ourstationhasnowbeenrunningthreemonths，withoutstoppingamoment，dayornight，andweinvariablygetoversixlampsperhorse-power，orsubstantiallythesameaswedoinourisolatedplants。
Wearenowlightingonehundredandninety-threebuildings，wiredforforty-fourhundredlamps，ofwhichabouttwo-thirdsareinconstantuse，andweareaddingadditionalhousesandlampsdaily。ThesefigurescanbeverifiedattheofficeoftheBoardofUnderwriters，wherecertificateswithfulldetailspermittingtheuseofourlightarefiledbytheirowninspector。Tolighttheselampswerunfromonetothreedynamos，accordingtothelampsinuseatanygiventime，andweshallstartadditionaldynamosasfastaswecanconnectmorebuildings。
Neitherasregardsthelossduetoresistance，norasregardsthenumberoflampsperhorse-power，istheretheslightesttroubleordisappointmentonthepartofourcompany，andyourcorrespondentisentirelyinerrorisassumingthatthereis。Letmesuggestthatif`Investigator\'
reallywishestoinvestigate，andiscompetentandwillingtolearntheexactfacts，hecandosoatthisoffice，wherethereisnomysteryofconcealment，but，onthecontrary，astrongdesiretocommunicatefactstointelligentinquirers。Suchamethodofinvestigatingmustcertainlybemoresatisfactorytoonehonestlyseekingknowledgethanthatoffirstassuminganerrorasthebasisofaquestion，andthendemandinganexplanation。
“Yoursverytruly，“S。B。EATON，President。“
Viewedfromthestandpointofovertwenty-sevenyearslater，thewisdomandnecessityofansweringanonymousnewspaperlettersofthiskindmightbedeemedquestionable，butitmustberememberedthat，althoughthePearlStreetstationwasworkingsuccessfully，andEdison\'scomprehensiveplanswereabundantlyvindicated，theenterprisewasabsolutelynewandonlyjuststeppingontheverythresholdofcommercialexploitation。Toenterinandpossessthelandrequiredtheconfidenceofcapitalandthegeneralpublic。HenceitwasnecessarytomaintainaconstantvigilancetodefeattheinsidiousattacksofcarpingcriticsandotherswhowouldattempttoinjuretheEdisonsystembymisleadingstatements。
Itwillbeinterestingtothemodernelectriciantonotethatwhenthispioneerstationwasstarted，andinfactforsomelittletimeafterward，therewasnotasingleelectricalinstrumentinthewholestation——
notavoltmeteroranammeter！Norwasthereacentralswitchboard！Eachdynamohaditsownindividualcontrolswitch。Thefeederconnectionswereallatthefrontofthebuilding，andthegeneralvoltagecontrolapparatuswasonthefloorabove。Anautomaticpressureindicatorhadbeendevisedandputinconnectionwiththemaincircuits。Itconsisted，generallyspeaking，ofanelectromagnetwithrelaysconnectingwitharedandabluelamp。Whentheelectricalpressurewasnormal，neitherlampwaslighted；butiftheelectromotiveforceroseaboveapredeterminedamountbyoneortwovolts，theredlamplightedup，andtheattendantatthehand-wheelofthefieldregulatorinsertedresistanceinthefieldcircuit，whereas，ifthebluelamplighted，resistancewascutoutuntilthepressurewasraisedtonormal。
Lateronthisprimitiveindicatorwassupplantedbythe“BradleyBridge，“acrudeformofthe“Howell“
pressureindicators，whichweresubsequentlyusedformanyyearsintheEdisonstations。
MuchcouldbeaddedtomakeacompletepictorialdescriptionofthehistoricPearlStreetstation，butitisnotwithinthescopeofthisnarrativetoenterintodiffusetechnicaldetails，interestingastheymaybetomanypersons。Wecannotclosethischapter，however，withoutmentionofthefateofthePearlStreetstation，whichcontinuedinsuccessfulcommercialoperationuntilJanuary2，1890，whenitwaspartiallydestroyedbyfire。Allthe“Jumbos“wereruined，exceptingNo。9，whichisstillaveneratedrelicinthepossessionoftheNewYorkEdisonCompany。
Luckily，theboilerswereunharmed。Belt-
drivengeneratorsandengineswerespeedilyinstalled，andthestationwasagaininoperationinafewdays。
Theuninjured“Jumbo，“No。9，againcontinuedtoperformitsduty。ButinthewordsofMr。CharlesL。
Clarke，“thegloryoftheoldPearlStreetstation，uniqueinbearingtheimpressofMr。Edison\'spersonality，and，asitwere，constructedwithhisownhands，disappearedintheflameandsmokeofthatThursdaymorningfire。“
Thefewdays\'interruptionoftheservicewastheonlyseriousonethathastakenplaceinthehistoryoftheNewYorkEdisonCompanyfromSeptember4，1882，tothepresentdate。ThePearlStreetstationwasoperatedforsometimesubsequenttothefire，butincreasingdemandsinthemeantimehavingledtotheconstructionofotherstations，themainsoftheFirstDistrictweresoonafterwardconnectedtoanotherplant，thePearlStreetstationwasdismantled，andthebuildingwassoldin1895。
Thepropheticinsightintothemagnitudeofcentral-
stationlightingthatEdisonhadwhenhewasstillexperimentingontheincandescentlampoverthirtyyearsagoisalittlelessthanastounding，whenitissoamplyverifiedintheoperationsoftheNewYorkEdisonCompanythesuccessoroftheEdisonElectricIlluminatingCompanyofNewYorkandmanyothers。
Attheendof1909theNewYorkEdisonCompanyalonewasoperatingtwenty-eightstationsandsubstations，havingatotalcapacityof159，500kilowatts。
Connectedwithitslineswereapproximately85，000
customerswiredfor3，813，899incandescentlampsandnearly225，000horse-powerthroughindustrialelectricmotorsconnectedwiththeundergroundservice。
Alargequantityofelectricalenergyisalsosuppliedforheatingandcooking，chargingautomobiles，chemicalandplatingwork，andvariousotheruses。
CHAPTERXVII
OTHEREARLYSTATIONS——THEMETER
WEhavenowseentheEdisonlightingsystemgivenacomplete，convincingdemonstrationinParis，London，andNewYork；andhavenotedstepstakenforitsintroductionelsewhereonbothsidesoftheAtlantic。TheParisplant，likethatattheCrystalPalace，wasatemporaryexhibit。TheLondonplantwaslesstemporary，butnotpermanent，supplyingbeforeitwastornoutnofewerthanthreethousandlampsinhotels，churches，stores，anddwellingsinthevicinityofHolbornViaduct。ThereMessrs。JohnsonandHammerputintopracticemanyoftheideasnowstandardintheart，andsecuredmuchusefuldatafortheworkinNewYork，ofwhichthestoryhasjustbeentold。
AsamatteroffactthefirstEdisoncommercialstationtobeoperatedinthiscountrywasthatatAppleton，Wisconsin，butitsonlyseriousclaimtonoticeisthatitwastheinitialoneofthesystemdrivenbywater-power。ItwentintoserviceAugust15，1882，aboutthreeweeksbeforethePearlStreetstation。Itconsistedofonesmalldynamoofacapacityoftwohundredandeightylightsof10c。p。
each，andwashousedinanunpretentiouswoodenshed。Thedynamo-electricmachine，thoughsmall，wasrobust，forunderallthevaryingspeedsofwater-
power，andthevicissitudesoftheplanttowhichit，belonged，itcontinuedinactiveuseuntil1899——
seventeenyears。
Edisonwasfromthefirstdeeplyimpressedwiththepossibilitiesofwater-power，and，asthisincidentshows，wasprompttoseizesuchaveryearlyopportunity。
Buthisattentionwasinrealityconcentratedcloselyonthesupplyofgreatcentresofpopulation，ataskwhichhethenfeltmightwelloccupyhislifetime；
andexceptinregardtofurnishingisolatedplantshedidnotpursuefurtherthedevelopmentofhydro-electricstations。Thatwaslefttoothers，andtotheapplicationofthealternatingcurrent，whichhasenabledengineerstoharnessremotepowers，and，withinthoroughlyeconomicallimits，transmitthousandsofhorse-powerasmuchastwohundredmilesatpressuresof80，000and100，000volts。Owingtohisinsistenceonlowpressure，directcurrentforuseindenselypopulateddistricts，astheonlysafeandtrulyuniversal，profitablewayofdeliveringelectricalenergytotheconsumers，Edisonhasbeenfrequentlyspokenofasanopponentofthealternatingcurrent。
Thisdoeshimaninjustice。AtthetimeameasurewasbeforetheVirginialegislature，in1890，tolimitthepermissiblepressuresofcurrentsoastorenderitsafe，hesaid：“Youwanttoallowhighpressurewherevertheconditionsaresuchthatbynopossibleaccidentcouldthatpressuregetintothehousesoftheconsumers；youwanttogivethemallthelatitudeyoucan。“Inexplainingthisheadded：“SupposeyouwanttotakethefallsdownatRichmond，andwanttoputupawater-power？Why，ifweerectastationatthefalls，itisagreateconomytogetituptothecity。Bydiggingacheaptrenchandputtinginaninsulatedcable，andconnectingsuchstationwiththecentralpartofRichmond，havingtheendofthecablecomeupintothestationfromtheearthandthereconnectedwithmotors，thepowerofthefallswouldbetransmittedtothesemotors。
Ifnowthemotorsweremadetorundynamosconveyinglow-pressurecurrentstothepublic，thereisnopossiblewaywherebythishigh-pressurecurrentcouldgettothepublic。“Inotherwords，Edisonmadethesharpfundamentaldistinctionbetweenhighpressurealternatingcurrentfortransmissionandlowpressuredirectcurrentfordistribution；andthisisexactlythepracticethathasbeenadoptedinallthegreatcitiesofthecountryto-day。Thereseemsnogoodreasonforbelievingthatitwillchange。ItmightperhapshavebeenaltogetherbetterforEdison，fromthefinancialstandpoint，ifhehadnotidentifiedhimselfsocompletelywithonekindofcurrent，butthatmadenodifferencetohim，asitwasamatterofconviction；andEdison\'sconvictionsaregranitic。
Moreover，thiscontroversyoverthetwocurrents，alternatinganddirect，whichhasbecomehistoricalinthefieldofelectricity——andissomethinglikethe“irrepressibleconflict“weheardofyearsagoinnationalaffairs——illustratesanotheraspectofEdison\'scharacter。Broadastheprairiesandfreeinthoughtasthewindsthatsweepthem，heisidiosyncraticallyopposedtolooseandwastefulmethods，toplansofempirethatneglectthepooratthegate。Every-
thinghehasdonehasbeenaimedattheconservationofenergy，thecontractionofspace，theintensificationofculture。Burbankandhistriberepresentinthevegetableworld，Edisoninthemechanical。
Notonlyhashedevelopeddistinctlynewspecies，buthehaselucidatedtheintensiveartofgetting$1200outofanelectricalacreinsteadof$12——amanuredmarket-gardeninsideLondonandaten-
bushelexhaustedwheatfarmoutsideLawrence，Kansas，beingtheantipodesofproductivity——yetveryfarshortofexemplifyingthedifferenceofelectricalyieldbetweenanacreofterritoryinEdison\'s“firstNewYorkdistrict“andanacreinsomesmalltown。
Edison\'slightingworkfurnishedanexcellentbasis——
infact，theonlyone——forthedevelopmentofthealternatingcurrentnowsogenerallyemployedincentral-
stationworkinAmerica；andintheMcGrawElectricalDirectoryofApril，1909，nofewerthan4164stationsoutof5780reporteditsuse。Whenthealternatingcurrentwasintroducedforpracticalpurposesitwasnotneededforarclighting，thecircuitforwhich，fromasingledynamo，wouldoftenbetwentyorthirtymilesinlength，itscurrenthavingapressureofnotlessthanfiveorsixthousandvolts。Forsomeyearsitwasnotfoundfeasibletooperatemotorsonalternating-currentcircuits，andthatreasonwasoftenurgedagainstitseriously。Itcouldnotbeusedforelectroplatingordeposition，norcoulditchargestoragebatteries，allofwhichareeasilywithintheabilityofthedirectcurrent。Butwhenitcametobeaquestionoflightingascatteredsuburb，agroupofdwellingsontheoutskirts，aremotecountryresidenceorafarm-house，thealternatingcurrent，inallelementssaveitsdanger，wasandisideal。Itsthinwirescanbecarriedcheaplyovervastareas，andateachlocalpointofconsumptionthetransformerofsizeexactlyproportionedtoitslocaltasktakesthehigh-voltagetransmissioncurrentandlowersitspotentialataratioof20or40to1，foruseindistributionandconsumptioncircuits。Thisevolutionhasbeenquitedistinct，withitsowninventorslikeGaulardandGibbsandStanley，butcamesubsequenttotheworkofsupplyingsmall，denseareasofpopulation；theartthusgrowingfromwithin，andusingeachnewgainasameansforfurtherachievement。
NorwastheeffectofsuchgreatadvancesasthosemadebyEdisonlimitedtotheelectricalfield。Everydepartmentofmechanicswasstimulatedandbenefitedtoanextraordinarydegree。Copperforthecircuitswasmorehighlyrefinedthaneverbeforetosecurethebestconductivity，andpuritywasinsistedonineverykindofinsulation。Edisonwasintolerantofshamandshoddy，andnothingwouldsatisfyhimthatcouldnotstandcross-examinationbymicroscope，test-tube，andgalvanometer。Itwas，perhaps，thesteam-engineonwhichthedeepestimprintforgoodwasmade，referredtoalreadyintheremarksofMr。F。J。Spragueintheprecedingchapter，butbestillustratedintheperfectionofthemodernhigh-
speedengineoftheArmington&Simstype。Unlesshecouldsecureanengineofsmootherrunningandmoreexactlygovernedandregulatedthanthoseavail-
ableforhisdynamoandlamp，Edisonrealizedthathewouldfinditalmostimpossibletogiveasteadylight。Hedidnotwanthiscustomerstocounttheheart-beatsoftheengineintheflickerofthelamp。
Notasingleenginewasevenwithingunshotofthestandardthussetup，buttheemergencycalledforthitsmaninGardinerC。Sims，atalenteddraughtsmananddesignerwhohadbeenengagedinlocomotiveconstructionandintheengineeringdepartmentoftheUnitedStatesNavy。Hemaybequotedastowhathappened：“Thedeepinterest，financialandmoral，andfriendlybackingIreceivedfromMr。
Edison，togetherwithvaluablesuggestions，enabledmetobringouttheengine；asIwasquitealoneintheworld——poor——Ihadfoundafriendwhoknewwhathewantedandexplaineditclearly。Mr。Edisonwasaleaderfaraheadofthetime。Hecompelledthedesignofthesuccessfulengine。
“Ourfirstenginecompelledtheinventingandmakingofasuitableengineindicatortoindicateit——theTabor。Heobtainedthedesiredspeedandloadwithafrictionbrake；alsoregulatorofspeed；butwaitedforanindicatortoverifyit。Thenagaintherewasnoknownwaytolubricateanengineforcontinuousrunning，andMr。EdisoninformedmethatasamarineenginestartedbeforetheshipleftNewYorkandcontinuedrunninguntilitreacheditshomeport，soanengineforhispurposesmustproducelightatalltimes。Thatwasaposertome，forafive-hours\'runwasaboutallthathadbeenrequireduptothattime。
“AdayortwolaterMr。Edisoninquired：`HowfarisitfromheretoLawrence；itisalongwalk，isn\'tit？\'
`Yes，rather。\'Hesaid：`OfcourseyouwillunderstandImeantwithoutoil。\'TosayIwasdeeplyperplexeddoesnotexpressmyfeelings。Wewereatthemachineworks，GoerckStreet。Istartedfortheoil-room，when，aboutentering，Isawasmallfunnellyingonthefloor。Ithadbeensteppedonandflattened。Itookitup，andithadsolvedtheengine-
oilingproblem——andmywalktoLawrencelikeatrampactor\'swasoff！Theeccentricstraphadaroundglassoil-cupwithabrassbasethatscrewedintothestrap。Itookitoff，andmakingasketch，wenttoDaveCunningham，havingthefunnelinmyhandtoillustratewhatIwantedmade。Irequestedhimtomakeasheet-brassoil-cupandsolderittothebaseIhad。Hedidso。Ithenhadastandardmadetoholdanotheroil-cup，soastoseeandregulatethedrop-feed。OnthiscombinationIobtainedapatentwhichisnowuniversallyused。“
ItisneedlesstosaythatinduecoursetheenginebuildersoftheUnitedStatesdevelopedavarietyofexcellentprimemoversforelectric-lightandpowerplants，andweregratefultotheartfromwhichsuchastimuluscametotheirindustry；butformanyyearsoneneversawanEdisoninstallationwithoutexpectingtofindoneormoreArmington&Simshigh-
speedenginespartofit。Thoughthetypehasgoneoutofexistence，likesomanyotherthingsthatareusefulintheirdayandgeneration，itwasonceaveryvitalpartoftheart，andonemoreillustrationofthatintimatemannerinwhichtheadvancesindifferentfieldsofprogressinteractandco-operate。
Edisonhadinstalledhishistoricfirstgreatcentral-
stationsysteminNewYorkonthemultiplearcsystemcoveredbyhisfeederandmaininvention，whichresultedinanotablesavinginthecostofconductorsasagainstastraighttwo-wiresystemthroughoutofthe“tree“kind。Hesoonforesawthatstillgreatereconomywouldbenecessaryforcommercialsuccessnotaloneforthelargerterritoryopening，butforthecompactdistrictsoflargecities。Beingfirmlyconvincedthattherewasawayout，hepushedasideamassofotherwork，andsettleddowntothisproblem，withtheresultthatonNovember20，1882，onlytwomonthsaftercurrenthadbeensentoutfromPearlStreet，heexecutedanapplicationforapatentcoveringwhatisnowknownasthe“three-wiresystem。“
Ithasbeenuniversallyrecognizedasoneofthemostvaluableinventionsinthehistoryofthelightingart。[13]
Itsuseresultedinasavingofover60percent。ofcopperinconductors，figuredonthemostfavorablebasispreviouslyknown，inclusiveofthosecalculatedunderhisownfeederandmainsystem。Sucheconomyofoutlaybeingeffectedinoneoftheheaviestitemsofexpenseincentral-stationconstruction，itwasnowmadepossibletoestablishplantsintownswherethelargeinvestmentwouldotherwisehavebeenquiteprohibitive。Theinventionisinuniversalusetoday，alikefordirectandforalternatingcurrent，andaswellintheequipmentoflargebuildingsasinthedistributionsystemofthemostextensivecentral-stationnetworks。Onecannotimaginetheartwithoutit。
[13]Fortechnicaldescriptionandillustrationofthisinvention，seeAppendix。
ThestrongpositionheldbytheEdisonsystem，underthestrenuouscompetitionthatwasalreadyspringingup，wasenormouslyimprovedbytheintroductionofthethree-wiresystem；anditgaveanimmediateimpetustoincandescentlighting。Desiringtoputthisnewsystemintopracticalusepromptly，andreceivingapplicationsforlicensesfromalloverthecountry，EdisonselectedBrockton，Massachusetts，andSunbury，Pennsylvania，asthetwotownsforthetrial。OfthesetwoBrocktonrequiredthelargerplant，butwiththeconductorsplacedunderground。Itwasthefirsttocompleteitsarrangementsandcloseitscontract。Mr。HenryVillard，itwillberemembered，hadmarriedthedaughterofGarrison，thefamousabolitionist，anditwasthroughhisrelationshipwiththeGarrisonfamilythatBrocktoncametohavethehonorofexemplifyingsosoontheprinciplesofanentirelynewart。Sunbury，however，wasamuchsmallerinstallation，employedoverheadconductors，andhencewasthefirstto“crossthetape。“Itwasspeciallysuitedforatrialplantalso，intheearlydayswhenayieldofsixoreightlampstothehorse-powerwasconsideredsubjectforcongratulation。ThetownbeingsituatedinthecoalregionofPennsylvania，goodcoalcouldthenbeobtainedthereatseventy-fivecentsaton。
TheSunburygeneratingplantconsistedofanArmington&SimsenginedrivingtwosmallEdisondynamoshavingatotalcapacityofaboutfourhundredlampsof16c。p。Theindicatinginstrumentswereofthecrudestconstruction，consistingoftwovoltmetersconnectedby“pressurewires“tothecentreofelectricaldistribution。Oneammeter，formeasuringthequantityofcurrentoutput，wasinterpolatedinthe“neutralbus“orthird-wirereturncircuittoindicatewhentheloadonthetwomachineswasoutofbalance。Thecircuitswereopenedandclosedbymeansofabouthalfadozenroughlymadeplug-switches。[14]The“bus-bars“toreceivethecurrentfromthedynamosweremadeofNo。000copperlinewire，straightenedoutandfastenedtothewoodensheathingofthestationbyironstapleswithoutanypresencetoinsulation。CommentinguponthisMr。
W。S。Andrews，detailedfromthecentralstaff，says：
“TheinteriorwindingoftheSunburystation，includingtherunningoftwothree-wirefeederstheentirelengthofthebuildingfrombacktofront，thewiringupofthedynamosandswitchboardandallinstruments，togetherwithbus-bars，etc——infact，alllaborandmaterialusedintheelectricalwiringinstallation——amountedtothesumof$90。IreceivedarathersharpletterfromtheNewYorkofficeexpostulatingforthisEXTRAVAGANTEXPENDITURE，andstatingthatgreateconomymustbeobservedinfuture！”
Thestreetconductorswereoftheoverheadpole-lineconstruction，andwereinstalledbytheconstructioncompanythathadbeenorganizedbyEdisontobuildandequipcentralstations。Aspecialtypeofstreetpolehadbeendevisedbyhimforthethree-wiresystem。
[14]Byreasonoftheexperiencegainedatthisstationthroughtheuseofthesecrudeplug-switches，Mr。Edisonstartedacompetitionamongafewofhisassistantstodevisesomethingbetter。
Theresultwastheinventionofa“breakdown“switchbyMr。
W。S。Andrews，whichwasacceptedbyMr。Edisonasthebestofthedevicessuggested，andwasdevelopedandusedforagreatmanyyearsafterward。
SupplementingthestoryofMr。AndrewsisthatofLieut。F。J。Sprague，whoalsogivesacuriousglimpseofthegloriousuncertaintiesandvicissitudesofthatformativeperiod。Mr。SpragueservedonthejuryattheCrystalPalaceExhibitionwithDarwin\'sson——
thepresentSirHorace——andafterthetestswereendedlefttheNavyandenteredEdison\'sserviceatthesuggestionofMr。E。H。Johnson，whowasEdison\'sshrewdrecruitingsergeantinthosedays：“IresignedsoonerthanJohnsonexpected，andhehadmeonhishands。Meanwhilehehadcalleduponmetomakeareportofthethree-wiresystem，knowninEnglandastheHopkinson，bothDr。JohnHopkinsonandMr。Edisonbeingindependentinventorsatpracticallythesametime。Ireportedonthat，leftLondon，andlandedinNewYorkonthedayoftheopeningoftheBrooklynBridgein1883——May24——
withayear\'sleaveofabsence。
“IreportedattheofficeofMr。EdisononFifthAvenueandtoldhimIhadseenJohnson。Helookedmeoverandsaid：`Whatdidhepromiseyou？\'I
replied：`Twenty-fivehundreddollarsayear。\'Hedidnotsaymuch，butlookedit。AboutthattimeMr。AndrewsandIcametogether。OnJuly2dofthatyearwewereorderedtoSunbury，andtobereadytostartthestationonthefourth。Theelectricalworkhadtobedoneinforty-eighthours！Havingtravelledaroundtheworld，Ihadcultivatedanindifferencetoanyspecialdifficultiesofthatkind。Mr。
AndrewsandIworkedincollaborationuntilthenightofthethird。IthinkhewasperhapsmoreappreciativethanIwasofthedisciplineoftheEdisonConstructionDepartment，andthoughtitwouldbewellforustowaituntilthemorningofthefourthbeforewestartedup。Isaidweweresentovertogetgoing，andinsistedonstartinguponthenightofthethird。WehadanArmington&Simsenginewithsight-feedoiler。Ihadneverseenone，anddidnotknowhowitworked，withtheresultthatwesoonburnedupthebabbittmetalinthebearingsandspentagoodpartofthenightgettingtheminorder。ThenextdayMr。Edison，Mr。Insull，andthechiefengineeroftheconstructiondepartmentappearedonthesceneandwantedtoknowwhathadhappened。
Theyfoundanenginesomewhatlooseinthebearings，andtherefollowedremarkswhichwouldnotlookwellinprint。Andrewsskippedfromunder；heobeyedorders；Ididnot。Buttheplantran，anditwasthefirstthree-wirestationinthiscountry。“
Seenfromyetanotherangle，theworriesofthisearlyworkwerenotmerelythoseofthemenonthe“firingline。“Mr。Insull，inspeakingofthisperiod，says：“Whenitwasfounddifficulttopushthecentral-
stationbusinessowingtothelackofconfidenceinitsfinancialsuccess，Edisondecidedtogointothebusinessofpromotingandconstructingcentral-stationplants，andheformedwhatwasknownastheThomasA。EdisonConstructionDepartment，whichheputmeinchargeof。Theorganizationwascrude，thesteam-engineeringtalentpoor，andowingtotheimpossibilityofgettinganyconsiderablecapitalsubscribed，theplantswereputinascheaplyaspossible。Ibelievethatthisconstructiondepartmentwasunkindlynamedthe`DestructionDepartment。\'
Itserveditspurpose；nevermadeanymoney；andI
hadtheunpleasanttaskofpresidingatitsobsequies。“
OnJuly4ththeSunburyplantwasputintocommercialoperationbyEdison，andheremainedaweekstudyingitsconditionsandwatchingforanyunforeseendifficultythatmightarise。Nothinghappened，however，tointerferewiththesuccessfulrunningofthestation，andfortwentyyearsthereafterthesametwodynamoscontinuedtofurnishlightinSunbury。
Theywerelaterusedasreservemachines，andfinally，withtheengine，retiredfromserviceaspartofthe“CollectionofEdisonia“；buttheyremaininpracticallyasgoodconditionaswheninstalledin1883。
Sunburywasalsoprovidedwiththefirstelectro-
chemicalmetersusedintheUnitedStatesoutsideNewYorkCity，sothatitservedalsotoaccentuateelectricalpracticeinamostvitalrespect——namely，themeasurementoftheelectricalenergysuppliedtocustomers。Atthistimeandlongafter，allarclightingwasdoneona“flatrate“basis。Thearclampinstalledoutsideacustomer\'spremises，orinacircuitforpublicstreetlighting，burnedsomanyhoursnightly，somanynightsinthemonth；andwaspaidforatthatrate，subjecttorebateforhourswhenthelampmightbeoutthroughaccident。Theearlyarclampswereratedtorequire9to10amperesofcurrent，at45voltspressureeach，receivingwhichtheywereestimatedtogive2000c。p。，whichwasarrivedatbyaddingtogetherthelightfoundatfourdifferentpositions，sothatinrealitytheactuallightwasabout500c。p。Fewofthesedatawereeveractuallyused，however；anditwasallmoreorlessamatterofguesswork，althoughthecentral-stationmanager，aimingtogivegoodservice，wouldnaturallyseethatthedynamosweresooperatedastomaintainassteadilyaspossiblethenormalpotentialandcurrent。
Thesameloosemethodsappliedtotheearlyattemptstouseelectricmotorsonarc-lightingcircuits，andcontractsweremadebasedonthesizeofthemotor，thewidthoftheconnectingbelt，ortheamountofpowerthecustomerthoughtheused——
neveronthemeasurementoftheelectricalenergyfurnishedhim。
HereagainEdisonlaidthefoundationofstandardpractice。Itistruethatevendowntothepresenttimetheflatrateisappliedtoagreatdealofincandescentlighting，eachlampbeingchargedforindividuallyaccordingtoitsprobableconsumptionduringeachmonth。Thismayanswer，perhaps，inasmallplacewherethemanagercangaugeprettycloselyfromactualobservationwhateachcustomerdoes；buteventhenthereareelementsofriskandwaste；andobviouslyinalargecitysuchamethodwouldsoonbelikelytoresultinfinancialdisastertotheplant。Edisonheldthattheelectricitysoldmustbemeasuredjustlikegasorwater，andheproceededtodevelopameter。Therewasinfinitescepticismaroundhimonthesubject，andwhileotherinventorswerealsogivingthesubjecttheirthought，thepublictookitforgrantedthatanythingsoutterlyintangibleaselectricity，thatcouldnotbeseenorweighed，andonlygavesecondaryevidenceofitselfattheexactpointofuse，couldnotbebroughttoaccurateregis-
tration。ThegeneralattitudeofdoubtwasexemplifiedbytheincidentinMr。J。P。Morgan\'soffice，notedinthelastchapter。Edison，however，hadsatisfiedhimselfthattherewerevariouswaysofaccomplishingthetask，andhaddeterminedthatthecurrentshouldbemeasuredonthepremisesofeveryconsumer。Hiselectrolyticmeterwasverysuccessful，andwasofwidespreaduseinAmericaandinEuropeuntiltheperfectionofmechanicalmetersbyElihuThomsonandothersbroughtthattypeintogeneralacceptance。HencetheEdisonelectrolyticmeterisnolongerused，despiteitsexcellentqualities。Houston&KennellyintheirElectricityinEverydayLifesumthematterupasfollows：“TheEdisonchemicalmeteriscapableofgivingfairmeasurementsoftheamountofcurrentpassing。Byreason，however，ofdissatisfactioncausedfromtheinabilityofcustomerstoreadtheindicationsofthemeter，ithasinlateryears，toagreatextent，beenreplacedbyregisteringmetersthatcanbereadbythecustomer。“
TheprincipleemployedintheEdisonelectrolyticmeteristhatwhichexemplifiesthepowerofelectricitytodecomposeachemicalsubstance。Inotherwordsitisadepositionbath，consistingofaglasscellinwhichtwoplatesofchemicallypurezincaredippedinasolutionofzincsulphate。Whenthelightsormotorsinthecircuitareturnedon，andacertaindefinitesmallportionofthecurrentisdivertedtoflowthroughthemeter，fromthepositiveplatetothenegativeplate，thelatterincreasesinweightbyreceivingadepositofmetalliczinc；thepositiveplatemeantimelosinginweightbythemetalthuscarriedawayfromit。Thisdifferenceinweightisaveryexactmeasureofthequantityofelectricity，ornumberofampere-hours，thathave，sotospeak，passedthroughthecell，andhenceofthewholeconsumptioninthecircuit。Theamountthusduefromthecustomerisascertainedbyremovingthecell，washinganddryingtheplates，andweighingtheminachemicalbalance。Associatedwiththissimpleformofapparatuswerevariousingeniousdetailsandrefinementstosecureregularityofoperation，freedomfrominaccuracy，andimmunityfromsuchtamperingaswouldpermittheftofcurrentordamage。Asthefreezingofthezincsulphatesolutionincoldweatherwouldcheckitsoperation，Edisonintroduced，forexample，intothemeteranincandescentlampandathermostatsoarrangedthatwhenthetemperaturefelltoacertainpoint，orroseaboveanotherpoint，itwascutinorout；andinthismannerthemetercouldbekeptfromfreezing。ThestandardEdisonmeterpracticewastoremovethecellsonceamonthtothemeter-roomofthecentral-stationcompanyforexamination，anothersetbeingsubstituted。Themeterwascheaptomanufactureandinstall，andnotatallliabletogetoutoforder。
InDecember，1888，Mr。W。J。JenksreadaninterestingpaperbeforetheAmericanInstituteofElectricalEngineersonthesixyearsofpracticalexperiencehaduptothattimewiththemeter，thenmoregenerallyinusethananyother。Itappearsfromthepaperthattwenty-threeEdisonstationswerethenequippedwith5187meters，whichwererelieduponforbillingthemonthlycurrentconsumptionof87，856lampsand350motorsof1000horse-powertotal。Thisrepresentedabout75percent。oftheentirelampcapacityofthestations。Therewasanaveragecostperlampformeteroperationoftwenty-
twocentsayear，andeachmetertookcareofanaverageofseventeenlamps。Itisworthyofnote，astothepromptnesswithwhichtheEdisonstationsbecamepayingproperties，thatfourofthemeteredstationswereearningupwardof15percent。ontheircapitalstock；threeothersbetween8and10percent。；
eightbetween5and8percent。；theothershavingbeeninoperationtooshortatimetoshowdefiniteresults，althoughtheyalsowentquicklytoadividendbasis。Reportsmadeinthediscussionatthemeetingbyengineersshowedthesimplicityandsuccessofthemeter。Mr。C。L。Edgar，oftheBostonEdisonsystem，statedthathehad800ofthemetersinservicecaredforbytwomenandthreeboys，thelatteremployedincollectingthemetercells；thetotalcostbeingperhaps$2500ayear。Mr。J。W。LiebwrotefromMilan，Italy，thathehadinuseontheEdisonsystemthere360metersrangingfrom350ampere-
hourspermonthupto30，000。
InthisconnectionitshouldbementionedthattheAssociationofEdisonIlluminatingCompaniesinthesameyearadoptedresolutionsunanimouslytotheeffectthattheEdisonmeterwasaccurate，andthatitsusewasnotexpensiveforstationsaboveonethousandlights；andthatthebestfinancialresultswereinvariablysecuredinastationsellingcurrentbymeter。Beforethesameassociation，atitsmeetinginSeptember，1898，atSaultSte。Marie，Mr。C。S。ShepardreadapaperonthemeterpracticeoftheNewYorkEdisonCompany，givingdataastothelargenumberofEdisonmetersinuseandthetransitiontoothertypes，ofwhichto-daythecompanyhasseveralonitscircuits：“UntilOctober，1896，theNewYorkEdisonCompanymetereditscurrentinconsumer\'spremisesexclusivelybytheold-stylechemicalmeters，ofwhichtherewereconnectedonthatdate8109。Itwasthendeterminedtopurchasenomore。“Mr。Shepardwentontostatethatthechemicalmetersweregraduallydisplaced，andthatonSeptember1，1898，therewereonthesystem5619mechanicaland4874chemical。Themetercontinuedingeneralserviceduring1899，andprobablyuptothecloseofthecentury。
Mr。Andrewsrelatesaratherhumorousmeterstoryofthoseearlydays：“ThemetermanatSunburywasafirmandenthusiasticbelieverinthecorrectnessoftheEdisonmeter，havingpersonallyverifieditsreadingmanytimesbyactualcomparisonoflamp-hours。
Oneday，onmakingoutacustomer\'sbill，hisconfidencereceivedasevereshock，forthemeterreadingshowedaconsumptioncallingforachargeofover$200，whereasheknewthatthelightactuallyusedshouldnotcostmorethanone-quarterofthatamount。
Heweighedandreweighedthemeterplates，andpursuedeverylineofinvestigationimaginable，butallinvain。Hefelthewasupagainstit，andthatperhapsanotherkindofajobwouldsuithimbetter。
Onceagainhewenttothecustomer\'smetertolookaround，whenasmallpieceofthickwireonthefloorcaughthiseye。Theproblemwassolved。Hesud-
denlyrememberedthatafterweighingtheplateshewentandputtheminthecustomer\'smeter；butthewireattachedtooneoftheplateswastoolongtogointhemeter，andhehadcutitoff。Hepickedupthepieceofwire，tookittothestation，weigheditcarefully，andfoundthatitaccountedforabout$150
worthofelectricity，whichwastheamountofthedifference。“
Edisonhimselfis，however，thebestrepertoryofstorieswhenitcomestothedifficultiesofthatearlyperiod，inconnectionwithmeteringthecurrentandchargingforit。Hemaybequotedatlengthasfollows：“WhenwestartedthestationatPearlStreet，inSeptember，1882，wewerenotverycommercial。Weputmanycustomerson，butdidnotmakeoutmanybills。Weweremoreinterestedinthetechnicalconditionofthestationthaninthecommercialpart。Wehadmetersinwhichthereweretwobottlesofliquid。Topreventtheseelectrolytesfromfreezingwehadineachmeterastripofmetal。Whenitgotverycoldthemetalwouldcontractandcloseacircuit，andthrowalampintocircuitinsidethemeter。Theheatfromthislampwouldpreventtheliquidfromfreezing，sothatthemetercouldgoondoingitsduty。Thefirstcolddayafterstartingthestation，peoplebegantocomeinfromtheiroffices，especiallydowninFrontStreetandWaterStreet，sayingthemeterwasonfire。Wereceivednumeroustelephonemessagesaboutit。
Somehadpouredwateronit，andotherssaid：`Sendamanrightuptoputitout。\'
“Afterthestationhadbeenrunningseveralmonthsandwastechnicallyasuccess，webegantolookafterthefinancialpart。Westartedtocollectsomebills；
butwefoundthatourbookswerekeptbadly，andthatthepersonincharge，whowasnobusinessman，hadneglectedthatpartofit。Infact，hedidnotknowanythingaboutthestation，anyway。SoIgotthedirectorstopermitmetohireamantorunthestation。ThiswasMr。Chinnock，whowasthensuperintendentoftheMetropolitanTelephoneCompanyofNewYork。IknewChinnocktobesquareandofgoodbusinessability，andinducedhimtoleavehisjob。Imadehimapersonalguarantee，thatifhewouldtakeholdofthestationandputitonacommercialbasis，andpay5percent。on$600，000，I
wouldgivehim$10，000outofmyownpocket。Hetookhold，performedthefeat，andIpaidhimthe$10，000。ImightremarkinthisconnectionthatyearsafterwardIappliedtotheEdisonElectricLightCompanyaskingthemiftheywouldnotliketopaymethismoney，asitwasspentwhenIwasveryhardupandmadethecompanyasuccess，andwasthefoundationoftheirpresentprosperity。Theysaidthey`weresorry\'——thatis，`WallStreetsorry\'——
andrefusedtopayit。Thisshowswhatanice，genial，generouslotofpeopletheyhaveoverinWallStreet。
“Chinnockhadagreatdealoftroublegettingthecustomersstraightenedout。IrememberonemanwhohadasaloononNassauStreet。Hehadhadhislightsburningfortwoorthreemonths。ItwasinJune，andChinnockputinabillfor$20；Julyfor$20；Augustabout$28；Septemberabout$35。Ofcoursethenightsweregettinglonger。Octoberabout$40；Novemberabout$45。ThenthemancalledChinnockup。Hesaid：`Iwanttoseeyouaboutmyelectric-lightbill。\'Chinnockwentuptoseehim。
Hesaid：`Areyouthemanagerofthiselectric-lightplant？\'Chinnocksaid：`Ihavethehonor。\'`Well，\'
hesaid，mybillhasgonefrom$20upto$28，$35，$45。Iwantyoutounderstand，youngfellow，thatmylimitis$60。\'
“AfterChinnockhadhadallthistroubleduetotheincompetencyoftheprevioussuperintendent，amancameinandsaidtohim：`DidMr。Blankhavechargeofthisstation？\'`Yes。\'`Didheknowanythingaboutrunningastationlikethis？\'Chinnocksaid：`DoesheKNOWanythingaboutrunningastationlikethis？No，sir。Hedoesn\'tevensuspectanything。\'
“OnedayChinnockcametomeandsaid：`Ihaveanewcustomer。\'Isaid：`Whatisit？\'Hesaid：
`Ihaveafellowwhoisgoingtotaketwohundredandfiftylights。\'Isaid：`Whatfor？\'`Hehasaplacedownhereinatoploft，andhasgottwohundredandfiftybarrelsof“rotgut“whiskey。Heputsalightdowninthebarrelandlightsitup，anditagesthewhiskey。\'ImetChinnockseveralweeksafter，andsaid：`Howisthewhiskeymangettingalong？\'
`It\'sallright；heispayinghisbill。Itfixesthewhiskeyandtakestheshudderrightoutofit。\'Somebodywentandtookoutapatentonthisidealater。
“InthesecondyearweputtheStockExchangeonthecircuitsofthestation，butwereveryfearfulthattherewouldbeacombinationofheavydemandandadarkday，andthattherewouldbeanoverloadedstation。Wehadanindexlikeasteam-gauge，calledanampere-meter，toindicatetheamountofcurrentgoingout。Iwasupat65FifthAvenueoneafternoon。
Asuddenblackcloudcameup，andItelephonedtoChinnockandaskedhimabouttheload。
Hesaid：`Weareuptothemuzzle，andeverythingisrunningallright。\'By-and-byitbecamesothickwecouldnotseeacrossthestreet。Itelephonedagain，andfeltsomethingwouldhappen，butfortunatelyitdidnot。IsaidtoChinnock：`Howisitnow？\'Hereplied：`Everythingisred-hot，andtheampere-
meterhasmadeseventeenrevolutions。\'“
In1883nosuchfittingsas“fixtureinsulators“wereknown。Itwasthecommonpracticetotwinetheelectricwiresaroundthedisusedgas-fixtures，fastenthemwithtapeorstring，andconnectthemtolamp-
socketsscrewedintoattachmentsunderthegas-
burners——elaboratedlaterintowhatwasknownasthe“combinationfixture。“Asaresultitwasnouncommonthingtoseebrightsparkssnappingbetweenthechandelierandthelightingwiresduringasharpthunder-storm。AstartlingmanifestationofthiskindhappenedatSunbury，whenthevividdisplaydrovenervousguestsofthehoteloutintothestreet，andtheprovidentialstormledMr。LutherStieringertoinventthe“insulatingjoint。“Thisseparatedthetwolightingsystemsthoroughly，wentintoimmediateservice，andisuniversallyusedto-day。
Returningtothemorespecificsubjectofpioneerplantsofimportance，thatatBrocktonmustbeconsideredforamoment，chieflyforthereasonthatthecitywasthefirstintheworldtopossessanEdisonstationdistributingcurrentthroughanundergroundthree-wirenetworkofconductors——theessentiallymoderncontemporaneouspractice，standardtwenty-
fiveyearslater。Itwasproposedtoemploypole-lineconstructionwithoverheadwires，andapartyofEdisonengineersdroveaboutthetowninanopenbarouchewithablue-printofthecircuitsandstreetsspreadoutontheirknees，todeterminehowmuchtree-trimmingwouldbenecessary。Whentheycametosomeheavilyshadedspots，thefinetreesweremarked“T“toindicatethattheworkingettingthroughthemwouldbe“tough。“Wherethetreesweresparseandthefoliagewasthin，thesamecheerfulbandofvandalsmarkedthespots“E“toindicatethatthereitwouldbe“easy“torunthewires。Inthosedayspublicopinionwasnotsoaliveasnowtothedesirabilityofpreservingshade-trees，andofenhancingthebeautyofacityinsteadofdestroyingit。
Brocktonhadagooddealofprideinitsfinetrees，andastrongsentimentwasverysoonarousedagainstthemutilationproposedsothoughtlessly。Theinvestorsintheenterprisewerereadyandanxioustomeettheextracostofputtingthewiresunderground。
Edison\'sownwisheswerealtogetherfortheuseofthemethodshehadsocarefullydevised；andhencethatbustlinghomeofshoemanufacturewassparedthisinflictionofmoreoverheadwires。
ThestationequipmentatBrocktonconsistedatfirstofthreedynamos，oneofwhichwassoarrangedastosupplybothsidesofthesystemduringlightloadsbyabreakdownswitchconnection。Thisarrangementinterferedwithcorrectmeterregistra-
tion，asthemetersononesideofthesystemregisteredbackwardduringthehoursinwhichthecombinationwasemployed。Hence，aftersupplyinganall-nightcustomerwhoselampswereononesideofthecircuits，thecompanymightbefoundtoowehimsomethingsubstantialinthemorning。Soonafterthestationwentintooperationthisingeniousplanwaschanged，andthethirddynamowasreplacedbytwoothers。TheEdisonconstructiondepartmenttookentirechargeoftheinstallationoftheplant，andtheformalopeningwasattendedonOctober1，1883，byMr。Edison，whothenremainedaweekinceaselessstudyandconsultationovertheconditionsdevelopedbythisinitialthree-wireundergroundplant。SomeideaoftheconfidenceinspiredbythefameofEdisonatthisperiodisshownbythefactthatthefirsttheatreeverlightedfromacentralstationbyincandescentlampswasdesignedthisyear，andopenedin1884atBrocktonwithanequipmentofthreehundredlamps。Thetheatrewasneverpipedforgas！ItwasalsofromtheBrocktoncentralstationthatcurrentwasfirstsuppliedtoafire-enginehouse——anotherdisplayofremarkablyearlybeliefinthetrustworthinessoftheservice，underconditionswherecontinuityoflightingwasvital。Thebuildingwasequippedinsuchamannerthatthestrikingofthefire-alarmwouldlighteverylampinthehouseautomaticallyandliberatethehorses。ItwasatthiscentralstationthatLieutenantSpraguebeganhishistoricworkontheelectricmotor；andherethatanotherdistinguishedengineerandinventor，Mr。H。WardLeonard，installedthemetersandbecamemeterman，inorderthathemightstudyineveryintimatedetailtheimprovementsandrefinementsnecessaryinthatbranchoftheindustry。
TheauthorsareindebtedforthesefactsandsomeotherdataembodiedinthisbooktoMr。W。J。Jenks，whoasmanagerofthisplantheremadehisdebutintheEdisonranks。Hehadbeenconnectedwithlocaltelephoneinterests，butresignedtotakeactivechargeofthisplant，imbibingquicklythetraditionalEdisonspirit，workinghardalldayandsleepinginthestationatnightonacotbroughtthereforthatpurpose。Itwasatimeofuninterruptedwatchfulness。Thedifficultyofobtainingengineersinthosedaystorunthehigh-speedenginesthreehundredandfiftyrevolutionsperminuteiswellillustratedbyanamusingincidentintheveryearlyhistoryofthestation。A
locomotiveengineerhadbeenengaged，asitwassupposedhewouldnotbeafraidofanything。Oneeveningtherecameasuddenflashoffireandaspluttering，sizzlingnoise。Therehadbeenashort-circuitonthecoppermainsinthestation。Thefiremanhidbehindtheboilerandtheengineerjumpedoutofthewindow。Mr。Spraguerealizedthetrouble，quicklythrewoffthecurrentandstoppedtheengine。
Mr。Jenksrelatesanotherhumorousincidentinconnectionwiththisplant：“OnenightIheardaknockattheofficedoor，andonopeningitsawtwowell-dressedladies，whoaskediftheymightbeshownthrough。Iinvitedthemin，takingthemfirsttotheboiler-room，whereIshowedthemthecoal-pile，explainingthatthiswasusedtogeneratesteamintheboiler。Wethenwenttothedynamo-room，whereIpointedoutthemachinesconvertingthesteam-
powerintoelectricity，appearinglaterintheformoflightinthelamps。Afterthattheywereshownthemetersbywhichtheconsumptionofcurrentwasmeasured。Theyappearedtobeinterested，andI
proceededtoenteruponacomparisonofcoalmadeintogasorburnedunderaboilertobeconvertedintoelectricity。Theladiesthankedmeeffusivelyandbroughttheirvisittoaclose。Astheywereabouttogothroughthedoor，oneofthemturnedtomeandsaid：`Wehaveenjoyedthisvisitverymuch，butthereisonequestionwewouldliketoask：Whatisitthatyoumakehere？\'“
TheBrocktonstationwasforalongtimeashowplantoftheEdisoncompany，andhadmanydistinguishedvisitors，amongthembeingProf。ElihuThomson，whowaspresentattheopening，andSirW。H。Preece，ofLondon。TheengineeringmethodspursuedformedthebasisofsimilarinstallationsinLawrence，Massachusetts，inNovember，1883；inFallRiver，Massachusetts，inDecember，1883；andinNewburgh，NewYork，thefollowingspring。
Anotherimportantplantofthisperioddeservesspecialmention，asitwasthepioneerinthelightingoflargespacesbyincandescentlamps。Thisinstallationoffivethousandlampsonthethree-wiresystemwasmadetoilluminatethebuildingsattheLouisville，Kentucky，Expositionin1883，and，owingtothecarefulsurveys，calculations，andpreparationsofH。M。
ByllesbyandthelateLutherStieringer，wascompletedandinoperationwithinsixweeksaftertheplacingoftheorder。TheJuryofAwards，inpresentingfourmedalstotheEdisoncompany，tookoccasiontopayahighcomplimenttotheefficiencyofthesystem。IthasbeenthoughtbymanythatthemagnificentsuccessofthisplantdidmoretostimulatethegrowthoftheincandescentlightingbusinessthananyothereventinthehistoryoftheEdisoncompany。ItwasliterallythebeginningoftheelectricalilluminationofAmericanExpositions，carriedlatertosuchsplendiddisplaysasthoseoftheChicagoWorld\'sFairin1893，Buffaloin1901，andSt。Louisin1904。
ThustheartwassetgoingintheUnitedStatesundermanydifficulties，butwitheverysignofcomingtriumph。ReferencehasalreadybeenmadetotheworkabroadinParisandLondon。ThefirstpermanentEdisonstationinEuropewasthatatMilan，Italy，forwhichtheorderwasgivenasearlyasMay，1882，byanenterprisingsyndicate。Lessthanayearlater，March3，1883，theinstallationwasreadyandwasputinoperation，theTheatreSantaRadegondahavingbeenpulleddownandanewcentral-
stationbuildingerectedinitsplace——probablythefirstedificeconstructedinEuropeforthespecificpurposeofincandescentlighting。Here“Jumbos“wereinstalledfromtimetotime，untilatlasttherewerenofewerthantenofthem；andcurrentwasfurnishedtocustomerswithatotalofnearlytenthousandlampsconnectedtothemains。ThispioneersystemwasoperatedcontinuouslyuntilFebruary9，1900，orforaperiodofaboutseventeenyears，whenthesturdyoldmachines，stillinexcellentcondition，wereputoutofservice，sothatalargerplantcouldbeinstalledtomeetthedemand。Thisnewplanttakeshigh-tensionpolyphasecurrentfromawater-powerthirtyorfortymilesawayatPaderno，ontheriverAdda，flowingfromtheApennines；
butdeliverslow-tensiondirectcurrentfordistributiontotheregularEdisonthree-wiresystemthroughoutMilan。
AboutthesametimethatsouthernEuropewasthusopeneduptothenewsystem，SouthAmericacameintoline，andthefirstEdisoncentralstationtherewasinstalledatSantiago，Chile，inthesummerof1883，underthesupervisionofMr。W。N。Stewart。
Thiswastheresultofthesuccessobtainedwithsmallisolatedplants，leadingtotheformationofanEdisoncompany。Itcanreadilybeconceivedthatatsuchanextremedistancefromthesourceofsupplyofapparatustheplantwassubjecttomanypeculiardifficultiesfromtheoutset，ofwhichMr。Stewartspeaksasfollows：“Imadeanexhibitionofthe`Jumbo\'inthetheatreatSantiago，andonthefirstevening，whenitwasfilledwiththearistocracyofthecity，Idiscoveredtomyhorrorthatthebindingwirearoundthearmaturewasslowlystrippingoffandgoingtopieces。Wehadnomeansofboringoutthefieldmagnets，andwecutgroovesinthem。Ithinkthemachineisstillrunning1907。ThestationwentintooperationsoonafterwithanequipmentofeightEdison`K\'dynamoswithcertainconditionsinimicaltoefficiency，butwhichhavenothinderedthesplendidexpansionofthelocalsystem。Withthoseeightdynamoswehadfourbeltsbetweeneachengineandthedynamo。Thesteampressurewaslimitedtoseventy-fivepoundspersquareinch。Wehadtwo-wireundergroundfeeders，sentwithoutanyplansorspecificationsfortheirinstallation。Thestationhadneithervoltmeternorammeter。Thecurrentpressurewasregulatedbyagalvanometer。
Wewereusingcoalcosting$12aton，andwerepaidforourlightincurrencyworthfiftycentsonthedollar。TheonlythingIcanbeproudofinconnectionwiththeplantisthefactthatIdidnotdesignit，thatonceinawhilewemadeouttopayitsoperatingexpenses，andthatoccasionallywecouldrunitforthreemonthswithoutatotalbreakdown。“
Itwasnotuntil1885thatthefirstEdisonstationinGermanywasestablished；buttheartwasstillveryyoung，andtheplantrepresentedpioneerlightingpracticeintheEmpire。ThestationatBerlincomprisedfiveboilers，andsixverticalsteam-enginesdrivingbybeltstwelveEdisondynamos，eachofaboutfifty-fivehorse-powercapacity。AmodelofthisstationispreservedintheDeutschenMuseumatMunich。InthebulletinoftheBerlinElectricityWorksforMay，1908，itissaidwithregardtotheeventsthatleduptothecreationofthesystem，asnotedalreadyattheRathenaucelebration：“Theyear1881wasamile-stoneinthehistoryoftheAllgemeineElektricitaetsGesellschaft。TheInternationalElectricalExpositionatPariswasintendedtoplacebeforetheeyesofthecivilizedworldtheachievementsofthecentury。AmongtheexhibitsofthatExpositionwastheEdisonsystemofincandescentlighting。ITBECAMETHEBASISOFMODERNHEAVYCURRENT
TECHNICS。“Thelastphraseisitalicizedasbeingahappyandauthoritativedescription，aswellasatribute。
Thischapterwouldnotbecompleteifitfailedtoincludesomereferencetoafewoftheearlierisolatedplantsofahistoriccharacter。NotehasalreadybeenmadeofthefirstEdisonplantsafloatontheJeannetteandColumbia，andthefirstcommercialplantintheNewYorklithographicestablishment。ThefirstmillplantwasplacedinthewoollenfactoryofJamesHarrisonatNewburgh，NewYork，aboutSeptember15，1881。Ayearlater，Mr。Harrisonwrotewithsomepride：“Ibelievemymillwasthefirstlightedwithyourelectriclight，andthereforemaybecalledNo。1。
BesidesbeingjobNo。1itisaNo。1job，andaNo。1
light，beingbetterandcheaperthangasandabsolutelysafeastofire。“Thefirststeam-yachtlightedbyincandescentlampswasJamesGordonBennett\'sNamouna，equippedearlyin1882withaplantforonehundredandtwentylampsofeightcandlepower，whichremainedinusetheremanyyearsafterward。
ThefirstEdisonplantinahotelwasstartedinOctober，1881，attheBlueMountainHouseintheAdirondacks，andconsistedoftwo“Z“dynamoswithacomplementofeightandsixteencandlelamps。
Thehotelissituatedatanelevationofthirty-fivehundredfeetabovethesea，andwasatthattimefortymilesfromtherailroad。Themachinerywastakenupinpiecesonthebacksofmulesfromthefootofthemountain。Theboilerswerefiredbywood，astheeconomicaltransportationofcoalwasaphysicalimpossibility。Forasix-hourrunoftheplantone-
quarterofacordofwoodwasrequired，atacostoftwenty-fivecentspercord。
ThefirsttheatreintheUnitedStatestobelightedbyanEdisonisolatedplantwastheBijouTheatre，Boston。Theinstallationofboilers，engines，dynamos，wiring，switches，fixtures，threestageregulators，andsixhundredandfiftylamps，wascompletedinelevendaysafterreceiptoftheorder，andtheplantwassuccessfullyoperatedattheopeningofthetheatre，onDecember12，1882。
ThefirstplanttobeplacedonaUnitedStatessteamshipwastheoneconsistingofanEdison“Z“
dynamoandonehundredandtwentyeight-candlelampsinstalledontheFishCommission\'ssteamerAlbatrossin1883。Themostinterestingfeatureofthisinstallationwastheemploymentofspecialdeep-
sealamps，suppliedwithcurrentthroughacableninehundredandfortyfeetinlength，forthepurposeofalluringfish。Bymeansofthebrilliancyofthelampsmarineanimalsinthelowerdepthswereattractedandtheneasilyensnared。
CHAPTERXVIII
THEELECTRICRAILWAY
EDISONhadnosoonerdesignedhisdynamoin1879thanheadoptedthesameformofmachineforuseasamotor。ThetwoareshownintheScientificAmericanofOctober18，1879，andarealike，exceptthatthedynamoisverticalandthemotorliesinahorizontalposition，thearticleremarking：“Itsconstructiondiffersbutslightlyfromtheelectricgenerator。“
Thiswasbutanevidenceofhisearlyappreciationoftheimportanceofelectricityasamotivepower；
butitwillprobablysurprisemanypeopletoknowthathewastheinventorofanelectricmotorbeforeheperfectedhisincandescentlamp。HisinterestinthesubjectwentbacktohisconnectionwithGeneralLeffertsinthedaysoftheevolutionofthestockticker。WhileEdisonwascarryingonhisshopatNewark，NewJersey，therewasconsiderableexcitementinelectricalcirclesoverthePaynemotor，inregardtotheallegedperformanceofwhichGovernorCornellofNewYorkandotherwealthycapitalistswerequiteenthusiastic。PaynehadashopinNewark，andinonesmallroomwasthemotor，weighingperhapssixhundredpounds。Itwasofcircularform，incasediniron，withtheendsofseveralsmallmagnetsstickingthroughthefloor。Apulleyandbelt，con-
nectedtoacircularsawlargerthanthemotor，permittedlargelogsofoaktimbertobesawedwitheasewiththeuseoftwosmallcellsofbattery。Edison\'sfriend，GeneralLefferts，hadbecomeexcitedandwasdeterminedtoinvestalargesumofmoneyinthemotorcompany，butknowingEdison\'sintimatefamiliaritywithallelectricalsubjectshewaswiseenoughtoaskhisyoungexperttogoandseethemotorwithhim。AtanappointedhourEdisonwenttotheofficeofthemotorcompanyandfoundtherethevenerableProfessorMorse，GovernorCornell，GeneralLefferts，andmanyotherswhohadbeeninvitedtowitnessaperformanceofthemotor。Theyallproceededtotheroomwherethemotorwasatwork。Payneputawireinthebinding-postofthebattery，themotorstarted，andanassistantbegansawingaheavyoaklog。Itworkedbeautifully，andsogreatwasthepowerdeveloped，apparently，fromthesmallbattery，thatMorseexclaimed：“IamthankfulthatIhavelivedtoseethisday。“ButEdisonkeptaclosewatchonthemotor。Theresultsweresoforeigntohisexperiencethatheknewtherewasatrickinit。Hesoondiscoveredit。Whileholdinghishandontheframeofthemotorhenoticedatremblecoincidentwiththeexhaustofanengineacrossthealleyway，andhethenknewthatthepowercamefromtheenginebyabeltunderthefloor，shiftedonandoffbyamagnet，theothermagnetsbeingablind。HewhisperedtotheGeneraltoputhishandontheframeofthemotor，watchtheexhaust，andnotethecoincidenttremor。TheGeneraldidso，andinaboutfifteensecondshesaid：“Well，Edison，Imustgonow。Thisthingisafraud。“Andthushesavedhismoney，althoughothersnotsoshrewdlyadvisedwereeasilypersuadedtoinvestbysuchademonstration。
Afewyearslater，in1878，EdisonwenttoWyomingwithagroupofastronomers，totesthistasimeterduringaneclipseofthesun，andsawthelandwhitetoharvest。
Henoticedthelonghaulstomarketorelevatorthatthefarmershadtomakewiththeirloadsofgrainatgreatexpense，andconceivedtheideathatasordinarysteam-railroadservicewastoocostly，lightelectricrailwaysmightbeconstructedthatcouldbeoperatedautomaticallyoversimpletracks，thepropellingmotorsbeingcontrolledatvariouspoints。
Cheaptobuildandcheaptomaintain，suchroadswouldbeagreatboontothenewerfarmingregionsoftheWest，wherethehighwayswerestillofthecrudestcharacter，andwheretransportationwasthegravestdifficultywithwhichthesettlershadtocontend。Theplanseemstohavehauntedhim，andhehadnosoonerworkedoutageneratorandmotorthatowingtotheirlowinternalresistancecouldbeoperatedefficiently，thanheturnedhishandtothepracticaltrialofsucharailroad，applicabletoboththehaulageoffreightandthetransportationofpassengers。Earlyin1880，whenthetremendousrushofworkinvolvedintheinventionoftheincandescentlampintermittedalittle，hebegantheconstructionofastretchoftrackclosetotheMenloParklaboratory，andatthesametimebuiltanelectriclocomotivetooperateoverit。
Thisisafittingstageatwhichtoreviewbrieflywhathadbeendoneinelectrictractionuptothatdate。Therewasabsolutelynoart，buttherehadbeenanumberofsporadicandveryinterestingexperimentsmade。ThehonorofthefirstattemptofanykindappearstorestwiththiscountryandwithThomasDavenport，aself-trainedblacksmith，ofBrandon，Vermont，whomadeasmallmodelofacircularelectricrailwayandcarsin1834，andexhibiteditthefollowingyearinSpringfield，Boston，andothercities。Ofcoursehedependeduponbatteriesforcurrent，butthefundamentalideawasembodiedofusingthetrackforthecircuit，onerailbeingpositiveandtheothernegative，andthemotorbeingplacedacrossorbetweentheminmultiplearctoreceivethecurrent。Sucharealsopracticallythemethodsofto-day。Thelittlemodelwasingoodpreservationuptotheyear1900，when，beingshippedtotheParisExposition，itwaslost，thesteamerthatcarrieditfounderinginmid-ocean。Theverybroadpatenttakenoutbythissimplemechanic，sofaraheadofhistimes，wasthefirstoneissuedinAmericaforanelectricmotor。Davenportwasalsothefirstmantoapplyelectricpowertotheprinting-press，in1840。InhistractionworkhehadaclosesecondinRobertDavidson，ofAberdeen，Scotland，whoin1839operatedbothalatheandasmalllocomotivewiththemotorhehadinvented。Hiswasthecreditoffirstactuallycarryingpassengers——twoatatime，overaroughplankroad——whileitissaidthathiswasthefirstmotortobetriedonrealtracks，thoseoftheEdinburgh-Glasgowroad，makingaspeedoffourmilesanhour。