heroes of the telegraph-第30部分

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。　　The　results　were　described　in　a　paper　'On　the　Radiation　of　Electricity；'　which；　in　1859；　he　posted　to　Professor　Poggendorff；　for　insertion　in　the　well…known　periodical；　the　ANNALEN　DER　PHYSIK。　　The　memoir　was　declined；　to　the　great　disappointment　of　the　sensitive　young　teacher。

Reis　had　studied　the　organs　of　hearing；　and　the　idea　of　an　apparatus　for　transmitting　sound　by　means　of　electricity　had　been　floating　in　his　mind　for　years。　　Incited　by　his　lessons　on　physics；　in　the　year　1860　he　attacked　the　problem；　and　was　rewarded　with　success。　　In　1862　he　again　tried　Poggendorff；　with　an　account　of　his　'Telephon；'　as　he　called　it；＇The　word　'telephone'　　occurs　in　Timbs'　REPOSITORY　OF　SCIENCE　AND　ART　for　1845；　　in　connection　With　a　signal　trumpet　operated　by　compressed　air。＇　but　his　second　offering　was　rejected　like　the　first。　　The　learned　professor；　it　seems；　regarded　the　transmission　of　speech　by　electricity　as　a　chimera；　but　Reis；　in　the　bitterness　of　wounded　feeling；　attributed　the　failure　to　his　being　'only　a　poor　schoolmaster。'

Since　the　invention　of　the　telephone；　attention　has　been　called　to　the　fact　that；　in　1854；　M。　Charles　Bourseul；　a　French　telegraphist；　＇Happily　still　alive　（1891）。＇　　had　conceived　a　plan　for　conveying　sounds　and　even　speech　by　electricity。　　'Suppose；'　he　explained；　'that　a　man　speaks　near　a　movable　disc　sufficiently　flexible　to　lose　none　of　the　vibrations　of　the　voice；　that　this　disc　alternately　makes　and　breaks　the　currents　from　a　battery：　　you　may　have　at　a　distance　another　disc　which　will　simultaneously　execute　the　same　vibrations。。。。　It　is　certain　that；　in　a　more　or　less　distant　future；　speech　will　be　transmitted　by　electricity。　I　have　made　　experiments　in　this　direction；　they　are　delicate　and　demand　time　and　patience；　but　the　approximations　obtained　promise　a　favourable　result。'＇See　Du　Moncel's　EXPOSE　DES　APPLICATIONS；　etc。＇

Bourseul　deserves　the　credit　of　being　perhaps　the　first　to　devise　an　electric　telephone　and　try　to　make　it；　but　to　Reis　belongs　the　honour　of　first　realising　the　idea。　　A　writer　may　plot　a　story；　or　a　painter　invent　a　theme　for　a　picture；　but　unless　he　execute　the　work；　of　what　benefit　is　it　to　the　world？　　True；　a　suggestion　in　mechanics　may　stimulate　another　to　apply　it　in　practice；　and　in　that　case　the　suggester　is　entitled　to　some　share　of　the　credit；　as　well　as　the　distinction　of　being　the　first　to　think　of　the　matter。　　But　it　is　best　when　the　original　deviser　also　carries　out　the　work；　and　if　another　should　independently　hit　upon　the　same　idea　and　bring　it　into　practice；　we　are　bound　to　honour　him　in　full；　though　we　may　also　recognise　the　merit　of　his　predecessor。

Bourseul's　idea　seems　to　have　attracted　little　notice　at　the　time；　and　was　soon　forgotten。　　Even　the　Count　du　Moncel；　who　was　ever　ready　to　welcome　a　promising　invention；　evidently　regarded　it　as　a　fantastic　notion。　　It　is　very　doubtful　if　Reis　had　ever　heard　of　it。　　He　was　led　to　conceive　a　similar　apparatus　by　a　study　of　the　mechanism　of　the　human　ear；　which　he　knew　to　contain　a　membrane；　or　'drum；'　vibrating　under　the　waves　of　sound；　and　communicating　its　vibrations　through　the　hammer…bone　behind　it　to　the　auditory　nerve。　　It　therefore　occurred　to　him；　that　if　he　made　a　diaphragm　in　imitation　of　the　drum；　and　caused　it　by　vibrating　to　make　and　break　the　circuit　of　an　electric　current；　he　would　be　able　through　the　magnetic　power　of　the　interrupted　current　to　reproduce　the　original　sounds　at　a　distance。

In　1837…8　Professor　Page；　of　Massachusetts；　had　discovered　that'　a　needle　or　thin　bar　of　iron；　placed　in　the　hollow　of　a　coil　or　bobbin　of　insulated　wire；　would　emit　an　audible　'tick'　at　each　interruption　of　a　current；　flowing　in　the　coil；　and　that　if　these　separate　ticks　followed　each　other　fast　enough；　by　a　rapid　interruption　of　the　current；　they　would　run　together　into　a　continuous　hum；　to　which　he　gave　the　name　of　'galvanic　music。'　The　pitch　of　this　note　would　　correspond　to　the　rate　of　interruption　of　the　current。　　From　these　and　other　discoveries　which　had　been　made　by　Noad；　Wertheim；　Marrian；　and　others；　Reis　knew　that　if　the　current　which　had　been　interrupted　by　his　vibrating　diaphragm　were　conveyed　to　a　distance　by　a　metallic　circuit；　　and　there　passed　through　a　coil　like　that　of　Page；　the　iron　needle　would　emit　a　note　like　that　which　had　caused　the　oscillation　of　the　transmitting　diaphragm。　　Acting　on　this　knowledge；　he　constructed　a　rude　telephone。

Dr。　Messel　informs　us　that　his　first　transmitter　consisted　of　the　bung　of　a　beer　barrel　hollowed　out　in　imitation　of　the　external　ear。　　The　cup　or　mouth…piece　thus　formed　was　closed　by　the　skin　of　a　German　sausage　to　serve　as　a　drum　or　diaphragm。　　To　the　back　of　this　he　fixed；　with　a　drop　of　sealing…wax；　a　little　strip　of　platinum；　representing　the　hammer…　bone；　which　made　and　broke　the　metallic　circuit　of　the　current　as　the　membrane　oscillated　under　the　sounds　which　impinged　against　it。　　The　current　thus　interrupted　was　conveyed　by　wires　to　the　receiver；　which　consisted　of　a　knitting…needle　loosely　surrounded　by　a　coil　of　wire　fastened　to　the　breast　of　a　violin　as　a　sounding…board。　　When　a　musical　note　was　struck　near　the　bung；　the　drum　vibrated　in　harmony　with　the　pitch　of　the　note；　the　platinum　lever　interrupted　the　metallic　circuit　of　the　current；　which；　after　traversing　the　conducting　wire；　passed　through　the　coil　of　the　receiver；　and　made　the　needle　hum　the　original　tone。　　This　primitive　arrangement；　we　are　told；　astonished　all　who　heard　it。　　＇It　is　now　in　the　museum　of　the　Reichs　Post…Amt；　Berlin。＇

Another　of　his　early　transmitters　was　a　rough　model　of　the　human　ear；　carved　in　oak；　and　provided　with　a　drum　which　actuated　a　bent　and　pivoted　lever　of　platinum；　making　it　open　and　close　a　springy　contact　of　platinum　foil　in　the　metallic　circuit　of　the　current。　　He　devised　some　ten　or　twelve　different　forms；　each　an　improvement　on　its　predecessors；　which　transmitted　music　fairly　well；　and　even　a　word　or　two　of　speech　with　more　or　less　perfection。　　But　the　apparatus　failed　as　a　practical　means　of　talking　to　a　distance。

The　discovery　of　the　microphone　by　Professor　Hughes　has　enabled　us　to　understand　the　reason　of　this　failure。　　The　transmitter　of　Reis　was　based　on　the　plan　of　interrupting　the　current；　and　the　spring　was　intended　to　close　the　contact　after　it　had　been　opened　by　the　shock　of　a　vibration。　　So　long　as　the　sound　was　a　musical　tone　it　proved　efficient；　for　a　musical　tone　is　a　regular　succession　of　vibrations。　　But　the　vibrations　of　speech　are　irregular　and　complicated；　and　in　order　to　transmit　them　the　current　has　to　be　varied　in　strength　without　being　altogether　broken。　　The　waves　excited　in　the　air　by　the　voice　should　merely　produce　corresponding　waves　in　the　current。　　In　short；　the　current　ought　to　UNDULATE　in　sympathy　with　the　　oscillations　of　the　air。　It　appears　from　the　report　of　Herr　Von　Legat；　inspector　of　the　Royal　Prussian　Telegraphs；　on　the　Reis　telephone；　published　in　1862；　that　the　inventor　was　quite　aware　of　this　principle；　but　his　instrument　was　not　well　adapted　to　apply　it。　　No　doubt　the　platinum　contacts　he　employed　in　the　transmitter　behaved　to　some　extent　as　a　crude　metal　microphone；　and　hence　a　few　words；　especially　familiar　or　expected　ones；　could　be　transmitted　and　distinguished　at　the　other　end　of　the　line。　　But　Reis　does　not　seem　to　have　realised　the　importance　of　not　entirely　breaking　the　circuit　of　the　current；　at　all　events；　his　metal　spring　is　not　in　practice　an　effective　provision　against　this；　for　it　allows　the　metal　contacts　to　jolt　too　far　apart；　and　thus　interrupt　the　current。　　Had　he　lived　to　modify　the　spring　and　the　form　or　material　of　his　contacts　so　as　to　keep　the　current　continuousas　he　might　have　done；　for　example；　by　using　carbon　for　platinumhe　would　have　forestalled　alike　Bell；　Edison；　and　Hughes　in　the　production　of　a　good　speaking　telephone。　　Reis　in　fact　was　trembling　on　the　verge　of　a　great　discovery；　which　was；　however；　reserved　for　others。

His　experiments　were　made　in　a　little　workshop　behind　his　home　at　Friedrichsdorff；　and　wires　were　run　from　it　to　an　upper　chamber。　Another　line　was　erected　between　the　physical　cabinet　at　Garnier's　Institute　across　the　playground　to　one　of　the　class…rooms；　and　there　was　a　tradition　in　the　school　that　the　boys　were　afraid　of　creating　an　uproar　in　the　room　for　fear　Herr　Reis　should　hear　them　with　his　'telephon。'

The　new　invention　was　published　to　the　world　in　a　lecture　before　the　Physical　Society　of　Frankfort　on　October　26；　1861；　and　a　description；　written　by　himself　for　the　JAHRESBERICHT；　a　month　or　two　later。　　It　excited　a　good　deal　of　scientific　notice　in　Germany；　models　of　it　were　sent　abroad；　to　London；　Dublin；　Tiflis；　and　other　places。　　It　became　a　subject　for　popular　lectures；　and　an　article　for　scientific　cabinets。　Reis　obtained　a　brief　renown；　but　the　reaction　soon　set　in。　　The　Physical　Society　of　Frankfort　turned　its　back　on　the　apparatus　which　had　given　it　lustre。　　Reis　resigned　his　membership　in　1867；　but　the　Free　German　Institute　of　Frankfort；　which　elected　him　an　honorary　member；　also　slighted　the　instrument　as　a　mere　'philosophical　toy。'　　At　first　it　was　a　dream；　and　now　it　is　a　plaything。　　Have　we　not　had　enough　of　that　superior　wi