the history of the telephone-第19章

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His　monumental　work　has　been　the　development　of　the　MULTIPLE　Switchboard；　a　much　more　brain…twisting　problem　than　the　building　of　the　Pyramids　or　the　digging　of　the　Panama　Canal。　The　earlier　types　of　switchboard　had　become　too　cumbersome　by　1885。　They　were　well　enough　for　five　hundred　wires　but　not　for　five　thousand。　In　some　exchanges　as　many　as　half　a　dozen　operators　were　necessary　to　handle　a　single　call；　and　the　clamor　and　confusion　were　becoming　unbearable。　Some　handier　and　quieter　way　had　to　be　devised；　and　thus　arose　the　Multiple　board。　The　first　crude　idea　of　such　a　way　had　sprung　to　life　in　the　brain　of　a　Chicago　man　named　L。　B。　Firman；　in　1879；　but　he　became　a　farmer　and　forsook　his　invention　in　its　infancy。

In　the　Multiple　board；　as　it　grew　up　under　the　hands　of　Scribner；　the　outgoing　wires　are　duplicated　so　as　to　be　within　reach　of　every　operator。　A　local　call　can　thus　be　answered　at　once　by　the　operator　who　receives　it；　and　any　operator　who　is　overwhelmed　by　a　sudden　rush　of　business　can　be　helped　by　her　companions。　Every　wire　that　comes　into　the　board　is　tasselled　out　into　many　ends；　and　by　means　of　a　〃busy　test；〃　invented　by　Scribner；　only　one　of　these　ends　can　be　put　into　use　at　a　time。　The　normal　limit　of　such　a　board　is　ten　thousand　wires；　and　will　always　remain　so；　unless　a　race　of　long…armed　giantesses　should　appear；　who　would　be　able　to　reach　over　a　greater　expanse　of　board。　At　present；　a　business　of　more　than　ten　thousand　lines　means　a　second　exchange。

The　Multiple　board　was　enormously　expensive。　It　grew　more　and　more　elaborate　until　it　cost　one…third　of　a　million　dollars。　The　telephone　men　racked　their　brains　to　produce　something　cheaper　to　take　its　place；　and　they　failed。　The　Multiple　boards　swallowed　up　capital　as　a　desert　swallows　water；　but　THEY　SAVED　TEN　SECONDS　ON　EVERY　CALL。　This　was　an　unanswerable　argument　in　their　favor；　and　by　1887　twenty…　one　of　them　were　in　use。

Since　then；　the　switchboard　has　had　three　or　four　rebuildings。　There　has　seemed　to　be　no　limit　to　the　demands　of　the　public　or　the　fertility　of　Scribner's　brain。　Persistent　changes　were　made　in　the　system　of　signalling。　The　first　signal；　used　by　Bell　and　Watson；　was　a　tap　on　the　diaphragm　with　the　finger…nail。　Soon　after…　wards　came　a　〃buzzer；〃　and　then　the　magneto…　electric　bell。　In　1887　Joseph　O'Connell；　of　Chicago；　conceived　of　the　use　of　tiny　electric　lights　as　signals；　a　brilliant　idea；　as　an　electric　light　makes　no　noise　and　can　be　seen　either　by　night　or　by　day。　In　1901；　J。　J。　Carty　invented　the　〃bridging　bell；〃　a　way　to　put　four　houses　on　a　single　wire；　with　a　different　signal　for　each　house。　This　idea　made　the　〃party　line〃　practicable；　and　at　once　created　a　boom　in　the　use　of　the　telephone　by　enterprising　farmers。

In　1896　there　came　a　most　revolutionary　change　in　switchboards。　All　things　were　made　new。　Instead　of　individual　batteries；　one　at　each　telephone；　a　large　common　battery　was　installed　in　the　exchange　itself。　This　meant　better　signalling　and　better　talking。　It　reduced　the　cost　of　batteries　and　put　them　in　charge　of　experts。　It　established　uniformity。　It　introduced　the　federal　idea　into　the　mechanism　of　a　telephone　system。　Best　of　all；　it　saved　FOUR　SECONDS　ON　EVERY　CALL。　The　first　of　these　centralizing　switchboards　was　put　in　place　at　Philadelphia；　and　other　cities　followed　suit　as　fast　as　they　could　afford　the　expense　of　rebuilding。　Since　then；　there　have　come　some　switchboards　that　are　wholly　automatic。　Few　of　these　have　been　put　into　use；　for　the　reason　that　a　switchboard；　like　a　human　body；　must　be　semi…automatic　only。　To　give　the　most　efficient　service；　there　will　always　need　to　be　an　expert　to　stand　between　it　and　the　public。

As　the　final　result　of　all　these　varying　changes　in　switchboards　and　signals　and　batteries；　there　grew　up　the　modern　Telephone　Exchange。　This　is　the　solar　plexus　of　the　telephone　body。　It　is　the　vital　spot。　It　is　the　home　of　the　switchboard。　It　is　not　any　one's　invention；　as　the　telephone　was。　It　is　a　growing　mechanism　that　is　not　yet　finished；　and　may　never　be；　but　it　has　already　evolved　far　enough　to　be　one　of　the　wonders　of　the　electrical　world。　There　is　probably　no　other　part　of　an　American　city's　equipment　that　is　as　sensitive　and　efficient　as　a　telephone　exchange。

The　idea　of　the　exchange　is　somewhat　older　than　the　idea　of　the　telephone　itself。　There　were　communication　exchanges　before　the　invention　of　the　telephone。　Thomas　B。　Doolittle　had　one　in　Bridgeport；　using　telegraph　instruments　Thomas　B。　A。　David　had　one　in　Pittsburg；　using　printing…telegraph　machines；　which　required　little　skill　to　operate。　And　William　A。　Childs　had　a　third；　for　lawyers　only；　in　New　York；　which　used　dials　at　first　and　afterwards　printing　machines。　These　little　exchanges　had　set　out　to　do　the　work　that　is　done　to…day　by　the　telephone；　and　they　did　it　after　a　fashion；　in　a　most　crude　and　expensive　way。　They　helped　to　prepare　the　way　for　the　telephone；　by　building　up　small　constituencies　that　were　ready　for　the　telephone　when　it　arrived。

Bell　himself　was　perhaps　the　first　to　see　the　future　of　the　telephone　exchange。　In　a　letter　written　to　some　English　capitalists　in　1878；　he　said：　〃It　is　possible　to　connect　every　man's　house；　office　or　factory　with　a　central　station；　so　as　to　give　him　direct　communication　with　his　neighbors。　。　。　。　It　is　conceivable　that　cables　of　telephone　wires　could　be　laid　underground；　or　suspended　overhead；　connecting　by　branch　wires　with　private　dwellings；　shops；　etc。；　and　uniting　them　through　the　main　cable　with　a　central　office。〃　This　remarkable　prophecy　has　now　become　stale　reading；　as　stale　as　Darwin's　〃Origin　of　Species；〃　or　Adam　Smith's　〃Wealth　of　Nations。〃　But　at　the　time　that　it　was　written　it　was　a　most　fanciful　dream。

When　the　first　infant　exchange　for　telephone　service　was　born　in　Boston；　in　1877；　it　was　the　tiny　offspring　of　a　burglar…alarm　business　operated　by　E。　T。　Holmes；　a　young　man　whose　father　had　originated　the　idea　of　protecting　property　by　electric　wires　in　1858。　Holmes　was　the　first　practical　man　who　dared　to　offer　telephone　service　for　sale。　He　had　obtained　two　telephones；　numbers　six　and　seven；　the　first　five　having　gone　to　the　junk…heap；　and　he　attached　these　to　a　wire　in　his　burglar…alarm　office。　For　two　weeks　his　business　friends　played　with　the　telephones；　like　boys　with　a　fascinating　toy；　then　Holmes　nailed　up　a　new　shelf　in　his　office；　and　on　this　shelf　placed　six　box…telephones　in　a　row。　These　could　be　switched　into　connection　with　the　burglar…alarm　wires　and　any　two　of　the　six　wires　could　be　joined　by　a　wire　cord。　Nothing　could　have　been　simpler；　but　it　was　the　arrival　of　a　new　idea　in　the　business　world。

The　Holmes　exchange　was　on　the　top　floor　of　a　little　building；　and　in　almost　every　other　city　the　first　exchange　was　as　near　the　roof　as　possible；　partly　to　save　rent　and　partly　because　most　of　the　wires　were　strung　on　roof…tops。　As　the　telephone　itself　had　been　born　in　a　cellar；　so　the　exchange　was　born　in　a　garret。　Usually；　too；　each　exchange　was　an　off…shoot　of　some　other　wire…using　business。　It　was　a　medley　of　makeshifts。　Almost　every　part　of　its　outfit　had　been　made　for　other　uses。　In　Chicago　all　calls　came　in　to　one　boy；　who　bawled　them　up　a　speaking…　tube　to　the　operators。　In　another　city　a　boy　received　the　calls；　wrote　them　on　white　alleys；　and　rolled　them　to　the　boys　at　the　switchboard。　There　was　no　number　system。　Every　one　was　called　by　name。　Even　as　late　as　1880；　when　New　York　boasted　fifteen　hundred　telephones；　names　were　still　in　use。　And　as　the　first　telephones　were　used　both　as　transmitters　and　receivers；　there　was　usually　posted　up　a　rule　that　was　highly　important：　〃Don't　Talk　with　your　Ear　or　Listen　with　your　Mouth。〃

To　describe　one　of　those　early　telephone　exchanges　in　the　silence　of　a　printed　page　is　a　wholly　impossible　thing。　Nothing　but　a　language　of　noise　could　convey　the　proper　impression。　An　editor　who　visited　the　Chicago　exchange　in　1879　said　of　it：　〃The　racket　is　almost　deafening。　Boys　are　rushing　madly　hither　and　thither；　while　others　are　putting　in　or　taking　out　pegs　from　a　central　framework　as　if　they　were　lunatics　engaged　in　a　game　of　fox　and　geese。〃　In　the　same　year　E。　J。　Hall　wrote　from　Buffalo　that　hi