heroes of the telegraph-第42部分

快捷操作: 按键盘上方向键 ← 或 → 可快速上下翻页 按键盘上的 Enter 键可回到本书目录页 按键盘上方向键 ↑ 可回到本页顶部! 如果本书没有阅读完，想下次继续接着阅读，可使用上方 "收藏到我的浏览器" 功能 和 "加入书签" 功能！

he　whole　of　NICHOLAS　NICKLEBY。'　To　the　invalid；　especially；　this　use　would　come　as　a　boon；　and　if　the　instrument　were　a　loud　speaker；　a　circle　of　listeners　could　be　entertained。　　How　interesting　it　would　be　to　have　NICHOLAS　NICKLEBY　read　to　us　in　the　voice　of　Dickens；　or　TAM　O'　SHANTER　in　that　of　Burns！　　If　the　idea　is　developed；　we　may　perhaps　have　circulating　libraries　which　issue　phonograms；　and　there　is　already　some　talk　of　a　phonographic　newspaper　which　will　prattle　politics　and　scandal　at　the　breakfast…table。　　Addresses；　sermons；　and　political　speeches　may　be　delivered　by　the　phonograph；　languages　taught；　and　dialects　preserved；　while　the　study　of　words　cannot　fail　to　benefit　by　its　performance。

Musicians　will　now　be　able　to　record　their　improvisations　by　a　phonograph　placed　near　the　instrument　they　are　playing。　　There　need　in　fact　be　no　more　'lost　chords。'　Lovers　of　music；　like　the　inventor　himself；　will　be　able　to　purchase　songs　and　pieces；　sung　and　played　by　eminent　performers；　and　reproduce　them　in　their　own　homes。　　Music…　sellers　will　perhaps　let　them　out；　like　books；　and　customers　can　choose　their　piece　in　the　shop　by　having　it　rehearsed　to　them。

In　preserving　for　us　the　words　of　friends　who　have　passed　away；　the　sound　of　voices　which　are　stilled；　the　phonograph　assumes　its　most　beautiful　and　sacred　character。　　The　Egyptians　treasured　in　their　homes　the　mummies　of　their　dead。　　We　are　able　to　cherish　the　very　accents　of　ours；　and；　as　it　were；　defeat　the　course　of　time　and　break　the　silence　of　the　grave。　The　voices　of　illustrious　persons；　heroes　and　statesmen；　orators；　actors；　and　singers；　will　go　down　to　posterity　and　visit　us　in　our　homes。　　A　new　pleasure　will　be　added　to　life。　　How　pleasant　it　would　be　if　we　could　listen　to　the　cheery　voice　of　Gordon；　the　playing　of　Liszt；　or　the　singing　of　Jenny　Lind！

Doubtless　the　rendering　of　the　phonograph　will　be　still　further　improved　as　time　goes　on　；　but　even　now　it　is　remarkable　；　and　the　inventor　must　be　considered　to　have　redeemed　his　promises　with　regard　to　it。　Notwithstanding　his　deafness；　the　development　of　the　instrument　has　been　a　labour　of　love　to　him；　and　those　who　knew　his　rare　inventive　skill　believed　that　he　would　some　time　achieve　success。　　It　is　his　favourite；　his　most　original；　and　novel　work。　　For　many　triumphs　of　mind　over　matter　Edison　has　been　called　the　'Napoleon　of　Invention；'　and　the　aptness　of　the　title　is　enhanced　by　his　personal　resemblance　to　the　great　conqueror。　　But　the　phonograph　is　his　victory　of　Austerlitz；　and；　like　the　printing…press　of　Gutenberg；　it　will　assuredly　immortalise　his　name。

'The　phonograph；'　said　Edison　of　his　favourite；　'is　my　baby；　and　I　expect　it　to　grow　up　a　big　fellow　and　support　me　in　my　old　age。'　　Some　people　are　still　in　doubt　whether　it　will　prove　more　than　a　curious　plaything；　but　even　now　it　seems　to　be　coming　into　practical　use　in　America；　if　not　in　Europe。

After　the　publication　of　the　phonograph；　Edison；　owing；　it　is　stated；　to　an　erroneous　description　of　the　instrument　by　a　reporter；　received　letters　from　deaf　people　inquiring　whether　it　would　enable　them　to　hear　well。　　This；　coupled　with　the　fact　that　he　is　deaf　himself；　turned　his　thoughts　to　the　invention　of　the　'megaphone；'　a　combination　of　one　large　speaking　and　two　ear…trumpets；　intended　for　carrying　on　a　conversation　beyond　the　ordinary　range　of　the　voicein　short；　a　mile　or　two。　　It　is　said　to　render　a　whisper　audible　at　a　distance　of　1000　yards；　but　its　very　sensitiveness　is　a　drawback；　since　it　gathers　up　extraneous　sounds。

To　the　same　category　belongs　the　'aerophone；'　which　may　be　described　as　a　gigantic　tympanum；　vibrated　by　a　piston　working　in　a　cylinder　of　compressed　air；　which　is　regulated　by　the　vibrations　of　the　sound　to　be　magnified。　　It　was　designed　to　call　out　fog　or　other　warnings　in　a　loud　and　penetrating　tone；　but　it　has　not　been　successful。

The　'magnetic　ore　separator'　is　an　application　of　magnetism　to　the　extraction　of　iron　particles　from　powdered　ores　and　unmagnetic　matter。　The　ground　material　is　poured　through　a　funnel　or　'hopper；'　and　falls　in　a　shower　between　the　poles　of　a　powerful　electro…magnet；　which　draws　the　metal　aside；　thus　removing　it　from　the　dress。

Among　Edison's　toys　and　minor　inventions　may　be　mentioned　a　'voice　mill；'　or　wheel　driven　by　the　vibrations　of　the　air　set　up　in　speaking。　It　consists　of　a　tympanum　or　drum；　having　a　stylus　attached　as　in　the　phonograph。　　When　the　tympanum　vibrates　under　the　influence　of　the　voice；　the　stylus　acts　as　a　pawl　and　turns　a　ratchet…wheel。　　An　ingenious　smith　might　apply　it　to　the　construction　of　a　lock　which　would　operate　at　the　command　of　'Open；　Sesame！'　Another　trifle　perhaps　worthy　of　note　is　his　ink；　which　rises　on　the　paper　and　solidifies；　so　that　a　blind　person　can　read　the　writing　by　passing　his　fingers　over　the　letters。

Edison's　next　important　work　was　the　adaptation　of　the　electric　light　for　domestic　illumination。　　At　the　beginning　of　the　century　the　Cornish　philosopher；　Humphrey　Davy；　had　discovered　that　the　electric　current　produced　a　brilliant　arch　or　'arc'　of　light　when　passed　between　two　charcoal　points　drawn　a　little　apart；　and　that　it　heated　a　fine　rod　of　charcoal　or　a　metal　wire　to　incandescencethat　is　to　say；　a　glowing　condition。　　A　great　variety　of　arc　lamps　were　afterwards　introduced；　and　Mr。　Staite；　on　or　about　the　year　1844…5；　invented　an　incandescent　lamp　in　which　the　current　passed　through　a　slender　stick　of　carbon；　enclosed　in　a　vacuum　bulb　of　glass。　　Faraday　discovered　that　electricity　could　be　generated　by　the　relative　motion　of　a　magnet　and　a　coil　of　wire；　and　hence　the　dynamo…electric　generator；　or　'dynamo；'　was　ere　long　invented　and　improved。

In　1878　the　boulevards　of　Paris　were　lit　by　the　arc　lamps　of　Jablochkoff　during　the　season　of　the　　Exhibition；　and　the　display　excited　a　widespread　interest　in　the　new　mode　of　illumination。　　It　was　too　brilliant　for　domestic　use；　however；　and；　as　the　lamps　were　connected　one　after　another　in　the　same　circuit　like　pearls　upon　a　string；　the　breakage　of　one　would　interrupt　the　current　and　extinguish　them　all　but　for　special　precautions。　　In　short；　the　electric　light　was　not　yet　'subdivided。'

Edison；　in　common　with　others；　turned　his　attention　to　the　subject；　and　took　up　the　neglected　incandescent　lamp。　　He　improved　it　by　reducing　the　rod　of　carbon　to　a　mere　filament　of　charcoal；　having　a　comparatively　high　resistance　and　resembling　a　wire　in　its　elasticity；　without　being　so　liable　to　fuse　under　the　intense　heat　of　the　current。　　This　he　moulded　into　a　loop；　and　mounted　inside　a　pear…shaped　bulb　of　glass。　The　bulb　was　then　exhausted　of　its　air　to　prevent　the　oxidation　of　the　carbon；　and　the　whole　hermetically　sealed。　　When　a　sufficient　current　was　passed　through　the　filament；　it　glowed　with　a　dazzling　lustre。　　It　was　not　too　bright　or　powerful　for　a　room；　it　produced　little　heat；　and　absolutely　no　fumes。　　Moreover；　it　could　be　connected　not　in　but　across　the　main　circuit　of　the　current；　and　hence；　if　one　should　break；　the　others　would　continue　glowing。　　Edison；　in　short；　had　　'subdivided'　the　electric　light。

In　October；　1878；　he　telegraphed　the　news　to　London　and　Paris；　where；　owing　to　his　great　reputation；　it　caused　an　immediate　panic　in　the　gas　market。　　As　time　passed；　and　the　new　illuminant　was　backward　in　appearing；　the　shares　recovered　their　old　value。　Edison　was　severely　blamed　for　causing　the　disturbance；　　but；　nevertheless；　his　announcement　had　been　verified　in　all　but　the　question　of　cost。　　The　　introduction　of　a　practical　system　of　electric　lighting　employed　his　resources　for　several　years。　　Dynamos；　types　of　lamps　and　conductors；　electric　meters；　safety　fuses；　and　other　appliances　had　to　be　invented。　　In　1882　he　returned　to　New　York；　to　superintend　the　installation　of　his　system　in　that　city。

His　researches　on　the　dynamo　caused　him　to　devise　what　he　calls　an　'harmonic　engine。'　It　consists　of　a　tuning…fork；　kept　in　vibration　by　two　small　electro…magnets；　　excited　with　three　or　four　battery　cells。　It　is　capable　of　working　a　small　pump；　but　is　little　more　than　a　scientific　curiosity。　　With　the　object　of　　transforming　heat　direct　from　the　furnace　into　electricity；　he　also　devised　a　'pyro…electric　generator；'　but　it　never　passed　beyond　the　experimental　stage。

The　same　may　be　said　for　his　pyro…electric　motor。　His　dynamo…electric　motors　and　system　of　electric　railways　are；　however；　a　more　promising　invention。　His　method　of　telegraphing　to　and　from　a　railway　train　in　motion；　by　induction　through　the　air　to　a　telegraph　wire　running　along　the　line；　is　very　　ingenious；　and　has　been　tried　with　a　fair　amount　of　success。

At　present　he　is　working　at　the　'Kinetograph；'　a　combination　of　the　phonograph　and　the　instantaneous　photograph　as　exhibited　in　the　zoetrope；　by　which　he　expects　to　produce　an　animated　picture　or　simulacrum　of　a　scene　in　real　life　or　the　drama；　with　its　appropriate　words　and　sounds。

Edison　now　resides　at　Llewellyn　Park；　Orange；　a　picturesque　suburb　of　New　York。　　His　laboratory　there　is　a　glorified　edition　of　Menlo　Park；　and　realises　the　inventor's　dream。　　The　main　building　is　of　brick；　in　three　stories；　but　there　are　several　annexes。　　Each　workshop　and　testing　room　is　devot