heroes of the telegraph-第7部分

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！
————未阅读完？加入书签已便下次继续阅读！


　the　luncheon　table　in　the　cabin；　he　began　to　talk　of　the　experiments　he　had　witnessed。　　Some　one　asked　if　the　speed　of　the　electricity　was　lessened　by　its　passage　through　a　long　wire；　and　Dr。　Jackson；　referring　to　a　trial　of　Faraday；　replied　that　the　current　was　apparently　instantaneous。　　Morse；　who　probably　remembered　his　old　lessons　in　the　subject；　now　remarked　that　if　the　presence　of　the　electricity　could　be　rendered　visible　at　any　point　of　the　circuit　he　saw　no　reason　why　intelligence　might　not　be　sent　by　this　means。

The　idea　became　rooted　in　his　mind；　and　engrossed　his　thoughts。　　Until　far　into　the　night　he　paced　the　deck　discussing　the　matter　with　Dr。　Jackson；　and　pondering　it　in　solitude。　　Ways　of　rendering　the　electricity　sensible　at　the　far　end　of　the　line　were　considered。　　The　spark　might　pierce　a　band　of　travelling　paper；　as　Professor　Day　had　mentioned　years　before；　it　might　decompose　a　chemical　solution；　and　leave　a　stain　to　mark　its　passage；　as　tried　by　Mr。　Dyar　in　1827；　Or　it　could　excite　an　electro…magnet；　which；　by　attracting　a　piece　of　soft　iron；　would　inscribe　the　passage　with　a　pen　or　pencil。　　The　signals　could　be　made　by　very　short　currents　or　jets　of　electricity；　according　to　a　settled　code。　Thus　a　certain　number　of　jets　could　represent　a　corresponding　numeral；　and　the　numeral　would；　in　its　turn；　represent　a　word　in　the　language。　　To　decipher　the　message；　a　special　code…book　or　dictionary　would　be　required。　　In　order　to　transmit　the　currents　through　the　line；　he　devised　a　mechanical　sender；　in　which　the　circuit　would　be　interrupted　by　a　series　of　types　carried　on　a　port…rule　or　composing…stick；　which　travelled　at　a　uniform　speed。　　Each　type　would　have　a　certain　number　of　teeth　or　projections　on　its　upper　face；　and　as　it　was　passed　through　a　gap　in　the　circuit　the　teeth　would　make　or　break　the　current。　　At　the　other　end　of　the　line　the　currents　thus　transmitted　would　excite　the　electro…magnet；　actuate　the　pencil；　and　draw　a　zig…zag　line　on　the　paper；　every　angle　being　a　distinct　signal；　and　the　groups　of　signals　representing　a　word　in　the　code。

During　the　voyage　of　six　weeks　the　artist　jotted　his　crude　ideas　in　his　sketch…book；　which　afterwards　became　a　testimony　to　their　date。　　That　he　cherished　hopes　of　his　invention　may　be　gathered　from　his　words　on　landing；　'Well；　Captain　Pell；　should　you　ever　hear　of　the　telegraph　one　of　these　days　as　the　wonder　of　the　world；　remember　the　discovery　was　made　on　the　good　ship　Sully。'

Soon　after　his　return　his　brothers　gave　him　a　room　on　the　fifth　floor　of　a　house　at　the　corner　of　Nassau　and　Beekman　Streets；　New　York。　　For　a　long　time　it　was　his　studio　and　kitchen；　his　laboratory　and　bedroom。　With　his　livelihood　to　earn　by　his　brush；　and　his　invention　to　work　out；　Morse　was　now　fully　occupied。　　His　diet　was　simple；　he　denied　himself　the　pleasures　of　society；　and　employed　his　leisure　in　making　models　of　his　types。　　The　studio　was　an　image　of　his　mind　at　this　epoch。　　Rejected　pictures　looked　down　upon　his　clumsy　apparatus；　type…moulds　lay　among　plaster…casts；　the　paint…pot　jostled　the　galvanic　battery；　and　the　easel　shared　his　attention　with　the　lathe。　　By　degrees　the　telegraph　allured　him　from　the　canvas；　and　he　only　painted　enough　to　keep　the　wolf　from　the　door。　　His　national　picture；　'The　Signing　of　the　First　Compact　on　Board　the　Mayflower；'　was　never　finished；　and　the　300　dollars　which　had　been　subscribed　for　it　were　finally　returned　with　interest。

For　Morse　by　nature　was　proud　and　independent；　with　a　sensitive　horror　of　incurring　debt。　　He　would　rather　endure　privation　than　solicit　help　or　lie　under　a　humiliating　obligation。　　His　mother　seems　to　have　been　animated　with　a　like　spirit；　for　the　Hon。　Amos　Kendall　informs　us　that　she　had　suffered　much　through　the　kindness　of　her　husband　in　becoming　surety　for　his　friends；　and　that　when　she　was　dying　she　exacted　a　promise　from　her　son　that　he　would　never　endanger　his　peace　of　mind　and　the　comfort　of　his　home　by　doing　likewise。

During　the　two　and　a　half　years　from　November；　1832；　to　the　summer　of　1835　he　was　obliged　to　change　his　residence　three　times；　and　want　of　money　prevented　him　from　combining　the　several　parts　of　his　invention　into　a　working　whole。　　In　1835；　however；　his　reputation　as　an　historical　painter；　and　the　esteem　in　which　he　was　held　as　a　man　of　culture　and　refinement；　led　to　his　appointment　as　the　first　Professor　of　the　Literature　of　the　Arts　of　Design　in　the　newly　founded　University　of　the　city　of　New　York。　　In　the　month　of　July　he　took　up　his　quarters　in　the　new　buildings　of　the　University　at　Washington　Square；　and　was　henceforth　able　to　devote　more　time　to　his　apparatus。　　The　same　year　Professor　Daniell；　of　King's　College；　London；　brought　out　his　constant…current　battery；　which　befriended　Morse　in　his　experiments；　as　it　afterwards　did　Cooke　and　Wheatstone；　Hitherto　the　voltaic　battery　had　been　a　source　of　trouble；　owing　to　the　current　becoming　weak　as　the　battery　was　kept　in　action。

The　length　of　line　through　which　Morse　could　work　his　apparatus　was　an　important　point　to　be　determined；　for　it　was　known　that　the　current　grows　feebler　in　proportion　to　the　resistance　of　the　wire　it　traverses。　Morse　saw　a　way　out　of　the　difficulty；　as　Davy；　Cooke；　and　Wheatstone　did；　by　the　device　known　as　the　relay。　　Were　the　current　too　weak　to　effect　the　marking　of　a　message；　it　might　nevertheless　be　sufficiently　strong　to　open　and　close　the　circuit　of　a　local　battery　which　would　print　the　signals。　　Such　relays　and　local　batteries；　fixed　at　intervals　along　the　line；　as　post…horses　on　a　turnpike；　would　convey　the　message　to　an　immense　distance。　　'If　I　can　succeed　in　working　a　magnet　ten　miles；'　said　Morse；'I　can　go　round　the　globe。　　It　matters　not　how　delicate　the　movement　may　be。'

According　to　his　own　statement；　he　devised　the　relay　in　1836　or　earlier；　but　it　was　not　until　the　beginning　of　1837　that　he　explained　the　device；　and　showed　the　working　of　his　apparatus　to　his　friend；　Mr。　Leonard　D。　Gale；　Professor　of　Chemistry　in　the　University。　　This　gentleman　took　a　lively　interest　in　the　apparatus；　and　proved　a　generous　ally　of　the　inventor。　　Until　then　Morse　had　only　tried　his　recorder　on　a　few　yards　of　wire；　the　battery　was　a　single　pair　of　plates；　and　the　electro…magnet　was　of　the　elementary　sort　employed　by　Moll；　and　illustrated　in　the　older　books。　　The　artist；　indeed；　was　very　ignorant　of　what　had　been　done　by　other　electricians；　and　Professor　Gale　was　able　to　enlighten　him。　　When　Gale　acquainted　him　with　some　results　in　telegraphing　obtained　by　Mr。　Barlow；　he　said　he　was　not　aware　that　anyone　had　even　conceived　the　notion　of　using　the　magnet　for　such　a　purpose。　　The　researches　of　Professor　Joseph　Henry　on　the　electro…magnet；　in　1830；　were　equally　unknown　to　Morse；　until　Professor　Gale　drew　his　attention　to　them；　and　in　accordance　with　the　results；　suggested　that　the　simple　electro…magnet；　with　a　few　turns　of　thick　wire　which　he　employed；　should　be　replaced　by　one　having　a　coil　of　long　thin　wire。　　By　this　change　a　much　feebler　current　would　be　able　to　excite　the　magnet；　and　the　recorder　would　mark　through　a　greater　length　of　line。　　Henry　himself；　in　1832；　had　devised　a　telegraph　similar　to　that　of　Morse；　and　signalled　through　a　mile　of　wire；　by　causing　the　armature　of　his　electro…magnet　to　strike　a　bell。　　This　was　virtually　the　first　electro…　magnetic　acoustic　telegraph。＇AMERICAN　JOURNAL　OF　SCIENCE。＇

The　year　of　the　telegraph1837was　an　important　one　for　Morse；　as　it　was　for　Cooke　and　Wheatstone。　　In　the　privacy　of　his　rooms　he　had　constructed；　with　his　own　hands；　a　model　of　his　apparatus；　and　fortune　began　to　favour　him。　　Thanks　to　Professor　Gale；　he　improved　the　electro…　magnet；　employed　a　more　powerful　battery；　and　was　thus　able　to　work　through　a　much　longer　line。　　In　February；　1837；　the　American　House　of　Representatives　passed　a　resolution　asking　the　Secretary　of　the　Treasury　to　report　on　the　propriety　of　establishing　a　system　of　telegraphs　for　the　United　States；　and　on　March　10　issued　a　circular　of　inquiry；　which　fell　into　the　hands　of　the　inventor；　and　probably　urged　him　to　complete　his　apparatus；　and　bring　it　under　the　notice　of　the　Government。　　Lack　of　mechanical　skill；　ignorance　of　electrical　science；　as　well　as　want　of　money；　had　so　far　kept　it　back。

But　the　friend　in　need　whom　he　required　was　nearer　than　he　anticipated。　On　Saturday；　September　2；　1837；　while　Morse　was　exhibiting　the　model　to　Professor　Daubeny；　of　Oxford；　then　visiting　the　States；　and　others；　a　young　man　named　Alfred　Vail　became　one　of　the　spectators；　and　was　deeply　impressed　with　the　results。　　Vail　was　born　in　1807；　a　son　of　Judge　Stephen　Vail；　master　of　the　Speedwell　ironworks　at　Morristown；　New　Jersey。　　After　leaving　the　village　school　his　father　took　him　and　his　brother　George　into　the　works；　but　though　Alfred　inherited　a　mechanical　turn　of　mind；　he　longed　for　a　higher　sphere；　and　on　attaining　to　his　majority　he　resolved　to　enter　the　Presbyterian　Church。　　In　1832　he　went　to　the　University　of　the　city　of　New　York；　where　he　graduated　in　October；　1836。　　Near　the　close　of　the　term；　however；　his　health　failed；　and　he　was　constrained　to　relinquish　his　clerical　aims。　　While　in　doubts　as　to　his　future　he　chanced　to　see　the　telegraph；　and　that　decided　him。　He　says：　　'I　accidentally　and　without　invitation　called　upon　Professor　Morse　at　the　University；　and　found　him　with　Professors　Torrey　and　Daubeny　in　the　mineralogical　cabinet　and　lecture…room　of　Professor　Gale；　where　Professor　Morse　was　exhibiting　to　these　gentlemen　an　apparatus　which　he　called　his　Electro…Magnetic　Telegraph。　　There　were　wires　suspended　in　the　room　running　from　one　end　of　it　to　the　other；　and　returning　many　times；　making　a　length　of　seventeen　hundred　feet。　　The　two　ends　of　the　wire　were　connected　with　an　electro…magnet　fastened　to　a　vertical　wooden　frame。　　In　front　of　the　magnet　was　its　armature；　and　also　a　wooden　lever　or　arm　fitted　at　its　extremity　to　hold　a　lead…　pencil。。。。　I　saw　this　instrument　work；　and　became　thoroughly　acquainted　with　the　principle　of　its　operation；　and；　I　may　say；　struck　with　the　rude　machine；　containing；　as　I　believed；　the　germ　of　what　was　destined　to　produce　great　changes　in　the　conditions　and　relations　of　mankind。　　I　well　recollect　the　impression