heroes of the telegraph-第16部分

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f　the　instrument；　appears　to　us　as　INTELLIGENCE。

The　recorder　is　now　in　use　in　all　four　quarters　of　the　globe；　from　Northern　Europe　to　Southern　Brazil；　from　China　to　New　England。　　Many　and　complete　are　the　adjustments　for　rendering　it　serviceable　under　a　wide　range　of　electrical　conditions　and　climatic　changes。　　The　siphon　is；　of　course；　in　a　mechanical　sense；　the　most　delicate　part；　but；　in　an　electrical　sense；　the　mouse…mill　proves　the　most　susceptible。　　It　is　essential　for　the　fine　marking　of　the　siphon　that　the　ink　should　neither　be　too　strongly　nor　too　feebly　electrified。　　When　the　atmosphere　is　moderately　humid；　a　proper　supply　of　electricity　is　generated　by　the　mouse…mill；　the　paper　is　sufficiently　moist；　and　the　ink　flows　freely。　But　an　excess　of　moisture　in　the　air　diminishes　the　available　supply　of　EXALTED　electricity。　　In　fact；　the　damp　depositing　on　the　parts　leads　the　electricity　away；　and　the　ink　tends　to　clog　in　the　siphon。　　On　the　other　hand；　drought　not　only　supercharges　the　ink；　but　dries　the　paper　so　much　that　it　INSULATES　the　siphon　point　from　the　metal　tablet　and　the　earth。　　There　is　then　an　insufficient　escape　for　the　electricity　of　the　ink　to　earth；　the　ink　ceases　to　flow　down　the　siphon；　the　siphon　itself　becomes　highly　electrified　and　agitated　with　vibrations　of　its　own；　the　line　becomes　spluttered　and　uncertain。

Various　devices　are　employed　at　different　stations　to　cure　these　local　complaints。　　The　electrician　soon　learns　to　diagnose　and　prescribe　for　this；　his　most　valuable　charge。　　At　Aden；　where　they　suffer　much　from　humidity；　the　mouse…mill　is　or　has　been　surrounded　with　burning　carbon。　At　Malta　a　gas　flame　was　used　for　the　same　purpose。　　At　Suez；　where　they　suffer　from　drought；　a　cloud　of　steam　was　kept　rising　round　the　instrument；　saturating　the　air　and　paper。　　At　more　temperate　places　the　ordinary　means　of　drying　the　air　by　taking　advantage　of　the　absorbing　power　of　sulphuric　acid　for　moisture　prevailed。　　At　Marseilles　the　recorder　acted　in　some　respects　like　a　barometer。　　Marseilles　is　subject　to　sudden　incursions　of　dry　northerly　winds；　termed　the　MISTRAL。　　The　recorder　never　failed　to　indicate　the　mistral　when　it　blew；　and　sometimes　even　to　predict　it　by　many　hours。　　Before　the　storm　was　itself　felt；　the　delicate　glass　pen　became　agitated　and　disturbed；　the　frail　blue　line　broken　and　irregular。　　The　electrician　knew　that　the　mistral　would　blow　before　long；　and；　as　it　rarely　blows　for　less　than　three　days　at　a　time；　that　rather　rude　wind；　so　dreaded　by　the　Marseillaise；　was　doubly　dreaded　by　him。

The　recorder　was　first　used　experimentally　at　St。　Pierre；　on　the　French　Atlantic　cable；　in　1869。　　This　was　numbered　0；　as　we　were　told　by　Mr。　White　of　Glasgow；　the　maker；　whose　skill　has　contributed　not　a　little　to　the　success　of　the　recorder。　　No。　1　was　first　used　practically　on　the　Falmouth　and　Gibraltar　cable　of　the　Eastern　Telegraph　Company　in　July；　1870。　　No。　1　was　also　exhibited　at　Mr。　（now　Sir　John）　Pender's　telegraph　soiree　in　1870。　　On　that　occasion；　memorable　even　beyond　telegraphic　circles；　'three　hundred　of　the　notabilities　of　rank　and　fashion　gathered　together　at　Mr。　Pender's　house　in　Arlington　Street；　Piccadilly；　to　celebrate　the　completion　of　submarine　communication　between　London　and　Bombay　by　the　successful　laying　of　the　Falmouth；　Gibraltar　and　Malta　and　the　British　Indian　cable　lines。'　Mr。　Pender's　house　was　literally　turned　outside　in；　the　front　door　was　removed；　the　courtyard　temporarily　covered　with　an　iron　roof　and　the　whole　decorated　in　the　grandest　style。　Over　the　gateway　was　a　gallery　filled　with　the　band　of　the　Scots　Fusilier　Guards；　and　over　the　portico　of　the　house　door　hung　the　grapnel　which　brought　up　the　1865　cable；　made　resplendent　to　the　eye　by　a　coating　of　gold　leaf。　　A　handsome　staircase；　newly　erected；　permitted　the　guests　to　pass　from　the　reception…room　to　the　drawing…room。　　In　the　grounds　at　the　back　of　the　house　stood　the　royal　tent；　where　the　Prince　of　Wales　and　a　select　party；　including　the　Duke　of　Cambridge　and　Lady　Mayo；　wife　of　the　Viceroy　of　India　at　that　time；　were　entertained　at　supper。　　Into　this　tent　were　brought　wires　from　India；　America；　Egypt；　and　other　places；　and　Lady　Mayo　sent　off　a　message　to　India　about　half…　past　eleven；　and　had　received　a　reply　before　twelve；　telling　her　that　her　husband　and　sons　were　quite　well　at　five　o'clock　the　next　morning。　The　recorder；　which　was　shown　in　operation；　naturally　stood　in　the　place　of　honour；　and　attracted　great　attention。

The　minor　features　of　the　recorder　have　been　　simplified　by　other　inventors　of　late；　for　example；　magnets　of　steel　have　been　substituted　for　the　electro…magnets　which　influence　the　swinging　coil；　and　the　ink；　instead　of　being　electrified　by　the　mouse…mill；　is　shed　on　the　paper　by　a　rapid　vibration　of　the　siphon　point。

To　introduce　his　apparatus　for　signalling　on　long　submarine　cables；　Sir　William　Thomson　entered　into　a　partnership　with　Mr。　C。　F。　Varley；　who　first　applied　condensers　to　sharpen　the　signals；　and　Professor　Fleeming　Jenkin；　of　Edinburgh　University。　　In　conjunction　with　the　latter；　he　also　devised　an　'automatic　curb　sender；'　or　key；　for　sending　messages　on　a　cable；　as　the　well…known　Wheatstone　transmitter　sends　them　on　a　land　line。

In　both　instruments　the　signals　are　sent　by　means　of　a　perforated　ribbon　of　paper；　but　the　cable　sender　was　the　more　complicated；　because　the　cable　signals　are　formed　by　both　positive　and　negative　currents；　and　not　merely　by　a　single　current；　whether　positive　or　negative。　　Moreover；　to　curb　the　prolongation　of　the　signals　due　to　induction；　each　signal　was　made　by　two　opposite　currents　in　successiona　positive　followed　by　a　negative；　or　a　negative　followed　by　a　positive；　as　the　case　might　be。　The　after…current　had　the　effect　of　curbing　its　precursor。　　This　self…　acting　cable　key　was　brought　out　in　1876；　and　tried　on　the　lines　of　the　Eastern　Telegraph　Company。

Sir　William　Thomson　took　part　in　the　laying　of　the　French　Atlantic　cable　of　1869；　and　with　Professor　Jenkin　was　engineer　of　the　Western　and　Brazilian　and　Platino…Brazilian　cables。　　He　was　present　at　the　laying　of　the　Para　to　Pernambuco　section　of　the　Brazilian　coast　cables　in　1873；　and　introduced　his　method　of　deep…sea　sounding；　in　which　a　steel　pianoforte　wire　replaces　the　ordinary　land　line。　　The　wire　glides　so　easily　to　the　bottom　that　'flying　soundings'　can　be　taken　while　the　ship　is　going　at　full　speed。　　A　pressure…gauge　to　register　the　depth　of　the　sinker　has　been　added　by　Sir　William。

About　the　same　time　he　revived　the　Sumner　method　of　finding　a　ship's　place　at　sea；　and　calculated　a　set　of　tables　for　its　ready　application。　His　most　important　aid　to　the　mariner　is；　however；　the　adjustable　compass；　which　he　brought　out　soon　afterwards。　　It　is　a　great　improvement　on　the　older　instrument；　being　steadier；　less　hampered　by　friction；　and　the　deviation　due　to　the　ship's　own　magnetism　can　be　corrected　by　movable　masses　of　iron　at　the　binnacle。

Sir　William　is　himself　a　skilful　navigator；　and　delights　to　cruise　in　his　fine　yacht；　the　Lalla　Rookh；　among　the　Western　Islands；　or　up　the　Mediterranean；　or　across　the　Atlantic　to　Madeira　and　America。　　His　interest　in　all　things　relating　to　the　sea　perhaps　arose；　or　at　any　rate　was　fostered；　by　his　experiences　on　the　Agamemnon　and　the　Great　Eastern。　Babbage　was　among　the　first　to　suggest　that　a　lighthouse　might　be　made　to　signal　a　distinctive　number　by　occultations　of　its　light；　but　Sir　William　pointed　out　the　merits　of　the　Morse　telegraphic　code　for　the　purpose；　and　urged　that　the　signals　should　consist　of　short　and　long　flashes　of　the　light　to　represent　the　dots　and　dashes。

Sir　William　has　done　more　than　any　other　　electrician　to　introduce　accurate　methods　and　apparatus　for　measuring　electricity。　　As　early　as　1845　his　mind　was　attracted　to　this　subject。　　He　pointed　out　that　the　experimental　results　of　William　Snow　Harris　were　in　accordance　with　the　laws　of　Coulomb。

In　the　Memoirs　of　the　Roman　Academy　of　Sciences　for　1857　he　published　a　description　of　his　new　divided　ring　electrometer；　which　is　based　on　the　old　electroscope　of　Bohnenberger　and　since　then　he　has　introduced　a　chain　or　series　of　beautiful　and　effective　instruments；　including　the　quadrant　electrometer；　which　cover　the　entire　field　of　electrostatic　measurement。　　His　delicate　mirror　galvanometer　has　also　been　the　forerunner　of　a　later　circle　of　equally　precise　apparatus　for　the　measurement　of　current　or　dynamic　electricity。

To　give　even　a　brief　account　of　all　his　physical　researches　would　require　a　separate　volume；　and　many　of　them　are　too　abstruse　or　mathematical　for　the　general　reader。　　His　varied　services　have　been　acknowledged　by　numerous　distinctions；　including　the　highest　honour　a　British　man　of　science　can　obtain　the　Presidency　of　the　Royal　Society　of　London；　to　which　he　was　elected　at　the　end　of　last　year。

Sir　William　Thomson　has　been　all　his　life　a　firm　believer　in　the　truth　of　Christianity；　and　his　great　scientific　attainments　add　weight　to　the　following　words；　spoken　by　him　when　in　the　chair　at　the　annual　meeting　of　the　Christian　Evidence　Society；　May　23；　1889　：…

'I　have　long　felt　that　there　was　a　general　impression　in　the　non…　scientific　world；　that　the　scientific　world　believes　Science　has　discovered　ways　of　explaining　all　the　facts　of　Nature　without　adopting　any　definite　belief　in　a　Creator。　　I　have　never　doubted　that　that　impression　was　utterly　groundless。　　It　seems　to　me　that　when　a　scientific　man　saysas　it　has　been　said　from　time　to　timethat　there　is　no　God；　he　does　not　express　his　own　ideas　clearly。　　He　is；　perhaps；　struggling　with　difficulties；　but　when　he　says　he　does　not　believe　in　a　creative　power；　I　am　convinced　he　does　not　faithfully　express　what　is　in　his　own　mind；　He　does　not　fully　express　his　own　ideas。　　He　is　out　of　his　depth。

'We　are　all　out　of　our　depth　when　we　approach　the　subject　of　life。　The　scientific　man；　in　looking　at　a　piece　of　dead　matter；　thinking　over　the　results　of　certain　combinations　which　he　can　impose　upon　it；　is　himself　a　living　miracle；　proving　that　there　is　something　beyond　that　mass　of　dead　matter　of　which　he　is　thinking。　　His　very　thought　is　in　itself　a　contradiction　to　the　idea　that　there　is　nothing　in　existence　but　de