heroes of the telegraph-第31部分

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y。'　　At　first　it　was　a　dream；　and　now　it　is　a　plaything。　　Have　we　not　had　enough　of　that　superior　wisdom　which　is　another　name　for　stupidity？　　The　dreams　of　the　imagination　are　apt　to　become　realities；　and　the　toy　of　to…day　has　a　knack　of　growing　into　the　mighty　engine　of　to…morrow。

Reis　believed　in　his　invention；　if　no　one　else　did；　and　had　he　been　encouraged　by　his　fellows　from　the　beginning；　he　might　have　brought　it　into　a　practical　shape。　　But　rebuffs　had　preyed　upon　his　sensitive　heart；　and　he　was　already　stricken　with　consumption。　　It　is　related　that；　after　his　lecture　on　the　telephone　at　Geissen；　in　1854；　Professor　Poggendorff；　who　was　present；　invited　him　to　send　a　description　of　his　instrument　to　the　ANNALEN。　　Reis　answered　him；'Ich　danke　Ihnen　recht　Sehr；　Herr　Professor　；　es　ist　zu　spaty。　Jetzt　will　ICH　nicht　ihn　schickeny。　Mein　Apparat　wird　ohne　Beschreibung　in　den　ANNALEN　bekannt　werden。'　（'Thank　you　very　much；　Professor；　but　it　is　too　late。　I　shall　not　send　it　now。　　My　apparatus　will　become　known　without　any　writing　in　the　ANNALEN。'）

Latterly　Reis　had　confined　his　teaching　and　study　to　matters　of　science；　but　his　bad　health　was　a　serious　impediment。　　For　several　years　it　was　only　by　the　exercise　of　a　strong　will　that　he　was　able　to　carry　on　his　duties。　　His　voice　began　to　fail　as　the　disease　gained　upon　his　lungs；　and　in　the　summer　of　1873　he　was　obliged　to　forsake　tuition　during　several　weeks。　　The　autumn　vacation　strengthened　his　hopes　of　recovery；　and　he　resumed　his　teaching　with　his　wonted　energy。　　But　this　was　the　last　flicker　of　the　expiring　flame。　　It　was　announced　that　he　would　show　his　new　gravity…machine　at　a　meeting　of　the　Deutscher　Naturforscher　of　Wiesbaden　in　September；　but　he　was　too　ill　to　appear。　　In　December　he　lay　down；　and；　after　a　long　and　painful　illness；　breathed　his　last　at　five　o'clock　in　the　afternoon　of　January　14；　1874

In　his　CURRICULUM　VITAE　he　wrote　these　words：　　'As　I　look　back　upon　my　life　I　call　indeed　say　with　the　Holy　Scriptures　that　it　has　been　〃labour　and　sorrow。〃　But　I　have　also　to　thank　the　Lord　that　He　has　given　me　His　blessing　in　my　calling　and　in　my　family；　and　has　bestowed　more　good　upon　me　than　I　have　known　how　to　ask　of　Him。　　The　Lord　has　helped　hitherto；　He　will　help　yet　further。'

Reis　was　buried　in　the　cemetery　of　Friedrichsdorff；　and　in　1878；　after　the　introduction　of　the　speaking　telephone；　the　members　of　the　Physical　Society　of　Frankfort　erected　over　his　grave　an　obelisk　of　red　sandstone　bearing　a　medallion　portrait。



CHAPTER　VIII。

GRAHAM　BELL。

The　first　to　produce　a　practicable　speaking　telephone　was　Alexander　Graham　Bell。　　He　was　born　at　Edinburgh　on　March　1；　1847；　and　comes　of　a　family　associated　with　the　teaching　of　elocution。　　His　grandfather　in　London；　his　uncle　in　Dublin；　and　his　father；　Mr。　Andrew　Melville　Bell；　in　Edinburgh；　were　all　professed　elocutionists。　　The　latter　has　published　a　variety　of　works　on　the　subject；　several　of　which　are　well　known；　especially　his　treatise　on　Visible　Speech；　which　appeared　in　Edinburgh　in　1868。　　In　this　he　explains　his　ingenious　method　of　instructing　deaf　mutes；　by　means　of　their　eyesight；　how　to　articulate　words；　and　also　how　to　read　what　other　persons　are　saying　by　the　motions　of　their　lips。　　Graham　Bell；　his　distinguished　son；　was　educated　at　the　high　school　of　Edinburgh；　and　subsequently　at　Warzburg；　in　Germany；　where　he　obtained　the　degree　of　Ph。D。　（Doctor　of　Philosophy）。　　While　still　in　Scotland　he　is　said　to　have　turned　his　attention　to　the　science　of　acoustics；　with　a　view　to　ameliorate　the　deafness　of　his　mother。

In　1873　he　accompanied　his　father　to　Montreal；　in　Canada；　where　he　was　employed　in　teaching　the　system　of　visible　speech。　　The　elder　Bell　was　invited　to　introduce　it　into　a　large　day…school　for　mutes　at　Boston；　but　he　declined　the　post　in　favour　of　his　son；　who　soon　became　famous　in　the　United　States　for　his　success　in　this　important　work。　　He　published　more　than　one　treatise　on　the　subject　at　Washington；　and　it　is；　we　believe；　mainly　through　his　efforts　that　thousands　of　deaf　mutes　in　America　are　now　able　to　speak　almost；　if　not　quite；　as　well　as　those　who　are　able　to　hear。

Before　he　left　Scotland　Mr。　Graham　Bell　had　turned　his　attention　to　telephony；　and　in　Canada　he　designed　a　piano　which　could　transmit　its　music　to　a　distance　by　means　of　electricity。　　At　Boston　he　continued　his　researches　in　the　same　field；　and　endeavoured　to　produce　a　telephone　which　would　not　only　send　musical　notes；　but　articulate　speech。

If　it　be　interesting　to　trace　the　evolution　of　an　animal　from　its　rudimentary　germ　through　the　lower　phases　to　the　perfect　organism；　it　is　almost　as　interesting　　to　follow　an　invention　from　the　original　model　through　the　faultier　types　to　the　finished　apparatus。

In　1860　Philipp　Reis；　as　we　have　seen；　produced　a　telephone　which　could　transmit　musical　notes；　and　even　a　lisping　word　or　two；　and　some　ten　years　later　Mr。　Cromwell　Fleetwood　Varley；　F。R。S。；　a　well…known　English　electrician；　patented　a　number　of　ingenious　devices　for　applying　the　musical　telephone　to　transmit　messages　by　dividing　the　notes　into　short　or　long　signals；　after　the　Morse　code；　which　could　be　interpreted　by　the　ear　or　by　the　eye　in　causing　them　to　mark　a　moving　paper。　　These　inventions　were　not　put　in　practice；　but　four　years　afterwards　Herr　Paul　la　Cour；　a　Danish　inventor；　experimented　with　a　similar　appliance　on　a　line　of　telegraph　between　Copenhagen　and　Fredericia　in　Jutland。　　In　this　a　vibrating　tuning…fork　interrupted　the　current；　which；　after　traversing　the　line；　passed　through　an　electro…magnet；　and　attracted　the　limbs　of　another　fork；　making　it　strike　a　note　like　the　transmitting　fork。　　By　breaking　up　the　note　at　the　sending　station　with　a　signalling　key；　the　message　was　heard　as　a　series　of　long　and　short　hums。　Moreover；　the　hums　were　made　to　record　themselves　on　paper　by　turning　the　electro…magnetic　receiver　into　a　relay；　which　actuated　a　Morse　printer　by　means　of　a　local　battery。

Mr。　Elisha　Gray；　of　Chicago；　also　devised　a　tone　telegraph　of　this　kind　about　the　same　time　as　Herr　La　Cour。　　In　this　apparatus　a　vibrating　steel　tongue　interrupted　the　current；　which　at　the　other　end　of　the　line　passed　through　the　electro…magnet　and　vibrated　a　band　or　tongue　of　iron　near　its　poles。　　Gray's　'harmonic　telegraph；'　with　the　vibrating　tongues　or　reeds；　was　afterwards　introduced　on　the　lines　of　the　Western　Union　Telegraph　Company　in　America。　　As　more　than　one　set　of　vibrationsthat　is　to　say；　more　than　one　notecan　be　sent　over　the　same　wire　simultaneously；　it　is　utilised　as　a　'multiplex'　or　many…ply　telegraph；　conveying　several　messages　through　the　same　wire　at　once；　and　these　can　either　be　interpreted　by　the　sound；　or　the　marks　drawn　on　a　ribbon　of　travelling　paper　by　a　Morse　recorder。

Gray　also　invented　a　'physiological　receiver；'　which　has　a　curious　history。　　Early　in　1874　his　nephew　was　playing　with　a　small　induction　coil；　and；　having　connected　one　end　of　the　secondary　circuit　to　the　zinc　lining　of　a　bath；　which　was　dry；　he　was　holding　the　other　end　in　his　left　hand。　　While　he　rubbed　the　zinc　with　his　right　hand　Gray　noticed　that　a　sound　proceeded　from　it；　which　had　the　pitch　and　quality　of　the　note　emitted　by　the　vibrating　contact　or　electrotome　of　the　coil。　　'I　immediately　took　the　electrode　in　my　hand；'　he　writes；　'and；　repeating　the　operation；　found　to　my　astonishment　that　by　rubbing　hard　and　rapidly　I　could　make　a　much　louder　sound　than　the　electrotome。　　I　then　changed　the　pitch　of　the　vibration；　and　found　that　the　pitch　of　the　sound　under　my　hand　was　also　changed；　agreeing　with　that　of　the　vibration。'　Gray　lost　no　time　in　applying　this　chance　discovery　by　designing　the　physiological　receiver；　which　consists　of　a　sounding…box　having　a　zinc　face　and　mounted　on　an　axle；　so　that　it　can　be　revolved　by　a　handle。　One　wire　of　the　circuit　is　connected　to　the　revolving　zinc；　and　the　other　wire　is　connected　to　the　finger　which　rubs　on　the　zinc。　　The　sounds　are　quite　distinct；　and　would　seem　to　be　produced　by　a　microphonic　action　between　the　skin　and　the　metal。

All　these　apparatus　follow　in　the　track　of　Reis　and　Bourseulthat　is　to　say；　the　interruption　of　the　current　by　a　vibrating　contact。　　It　was　fortunate　for　Bell　that　in　working　with　his　musical　telephone　an　accident　drove　him　into　a　new　path；　which　ultimately　brought　him　to　the　invention　of　a　speaking　telephone。　　He　began　his　researches　in　1874　with　a　musical　telephone；　in　which　he　employed　the　interrupted　current　to　vibrate　the　receiver；　which　consisted　of　an　electro…magnet　causing　an　iron　reed　or　tongue　to　vibrate；　but；　while　trying　it　one　day　with　his　assistant；　Mr。　Thomas　A。　Watson；　it　was　found　that　a　reed　failed　to　respond　to　the　intermittent　current。　　Mr。　Bell　desired　his　assistant；　who　was　at　the　other　end　of　the　line；　to　pluck　the　reed；　thinking　it　had　stuck　to　the　pole　of　the　magnet。　　Mr。　Watson　complied；　and　to　his　astonishment　Bell　observed　that　the　corresponding　reed　at　his　end　of　the　line　thereupon　began　to　vibrate　and　emit　the　same　note；　although　there　was　no　interrupted　current　to　make　it。　　A　few　experiments　soon　showed　that　his　reed　had　been　set　in　vibration　by　the　magneto…electric　currents　induced　in　the　line　by　the　mere　motio