heroes of the telegraph-第22章

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　business；　and　whose　name；　as　Sir　Josiah　Mason；　will　ever　be　remembered　for　his　munificent　endowment　of　education。　　It　was　agreed　that　I　should　not　be　judged　by　the　novelty　of　my　invention；　but　by　the　results　which　I　promised；　namely；　of　being　able　to　deposit　with　a　smooth　surface　30　dwt。　of　silver　upon　a　　dish…cover；　the　crystalline　structure　of　the　deposit　having　theretofore　been　a　source　of　difficulty。　　In　this　I　succeeded；　and　I　was　able　to　return　to　my　native　country　and　my　mechanical　engineering　a　comparative　Croesus。

'But　it　was　not　for　long；　as　in　the　following　year　（1844）　I　again　landed　in　the　Thames　with　another　invention；　worked　out　also　with　my　brother；　namely；　the　chronometric　governor；　which；　though　less　successful；　commercially　speaking；　than　the　first；　obtained　for　me　the　advantage　of　bringing　me　into　contact　with　the　engineering　world；　and　of　fixing　me　permanently　in　this　country。　　This　invention　was　in　course　of　time　applied　by　Sir　George　Airy；　the　then　Astronomer…Royal；　for　regulating　the　motion　of　his　great　transit　and　touch…recording　instrument　at　the　Royal　Observatory；　where　it　still　continues　to　be　employed。

'Another　early　subject　of　mine；　the　anastatic　printing　process；　found　favour　with　Faraday；　〃the　great　and　the　good；〃　who　made　it　the　subject　of　a　Friday　evening　lecture　at　the　Royal　Institution。　　These　two　circumstances；　combined；　obtained　for　me　an　entry　into　scientific　circles；　and　helped　to　sustain　me　in　difficulty；　until；　by　dint　of　a　certain　determination　to　win；　I　was　able　to　advance　step　by　step　up　to　this　place　of　honour；　situated　within　a　gunshot　of　the　scene　of　my　earliest　success　in　life；　but　separated　from　it　by　the　time　of　a　generation。　　But　notwithstanding　the　lapse　of　time；　my　heart　still　beats　quick　each　time　I　come　back　to　the　scene　of　this；　the　determining　incident　of　my　life。'

The　'anastatic'　process；　described　by　Faraday　in　1845；　and　partly　due　to　Werner　Siemens；　was　a　method　of　reproducing　printed　matter　by　transferring　the　print　from　paper　to　plates　of　zinc。　　Caustic　baryta　was　applied　to　the　printed　sheet　to　convert　the　resinous　ingredients　of　the　ink　into　an　insoluble　soap；　the　stearine　being　precipitated　with　sulphuric　acid。　　The　letters　were　then　transferred　to　the　zinc　by　pressure；　so　as　to　be　printed　from。　　The　process；　though　ingenious　and　of　much　interest　at　the　time；　has　long　ago　been　superseded　by　photographic　methods。

Even　at　this　time　Siemens　had　several　irons　in　the　fire。　　Besides　the　printing　process　and　the　chronometric　governor；　which　operated　by　the　differential　movement　between　the　engine　and　a　chronometer；　he　was　occupied　with　some　minor　improvements　at　Hoyle's　Calico　Printing　Works。　He　also　engaged　in　railway　works　from　time　to　time；　and　in　1846　he　brought　out　a　double　cylinder　air…pump；　in　which　the　two　cylinders　are　so　combined；　that　the　compressing　side　of　the　first　and　larger　cylinder　communicated　with　the　suction　side　of　the　second　and　smaller　cylinder；　and　the　limit　of　exhaustion　was　thereby　much　extended。　　The　invention　was　well　received　at　the　time；　but　is　now　almost　forgotten。

Siemens　had　been　trained　as　a　mechanical　engineer；　and；　although　he　became　an　eminent　electrician　in　later　life；　his　most　important　work　at　this　early　stage　was　non…electrical；　indeed；　the　greatest　achievement　of　his　life　was　non…electrical；　for　we　must　regard　the　regenerative　furnace　as　his　MAGNUM　OPUS。　　Though　in　1847　he　published　a　paper　in　Liebig's　ANNALEN　DER　CHEMIE　on　the　'Mercaptan　of　Selenium；'　his　mind　was　busy　with　the　new　ideas　upon　the　nature　of　heat　which　were　promulgated　by　Carnot；　Clayperon；　Joule；　Clausius；　Mayer；　Thomson；　and　Rankine。　　He　discarded　the　older　notions　of　heat　as　a　substance；　and　accepted　it　as　a　form　of　energy。　　Working　on　this　new　line　of　thought；　which　gave　him　an　advantage　over　other　inventors　of　his　time；　he　made　his　first　attempt　to　economise　heat；　by　constructing；　in　1847；　at　the　factory　of　Mr。　John　Hick；　of　Bolton；　an　engine　of　four　horse…power；　having　a　condenser　provided　with　regenerators；　and　utilising　superheated　steam。　　Two　years　later　he　continued　his　experiments　at　the　works　of　Messrs。　Fox；　Henderson；　and　Co。；　of　Smethwick；　near　Birmingham；　who　had　taken　the　matter　in　hand。　　The　use　of　superheated　steam　was；　however；　attended　with　many　practical　difficulties；　and　the　invention　was　not　entirely　successful；　but　it　embraced　the　elements　of　success；　and　the　Society　of　Arts；　in　1850；　acknowledged　the　value　of　the　principle；　by　awarding　Mr。　Siemens　a　gold　medal　for　his　regenerative　condenser。　　Various　papers　read　before　the　Institution　of　Mechanical　Engineers；　the　Institution　of　Civil　Engineers；　or　appearing　in　DINGLER'S　JOURNAL　and　the　JOURNAL　OF　THE　FRANKLIN　INSTITUTE　about　this　time；　illustrate　the　workings　of　his　mind　upon　the　subject。　　That　read　in　1853；　before　the　Institution　of　Civil　Engineers；　'On　the　Conversion　of　Heat　into　Mechanical　Effect；'　was　the　first　of　a　long　series　of　communications　to　that　learned　body；　and　gained　for　its　author　the　Telford　premium　and　medal。　　In　it　he　contended　that　a　perfect　engine　would　be　one　in　which　all　the　heat　applied　to　the　steam　was　used　up　in　its　expansion　behind　a　working　piston；　leaving　none　to　be　sent　into　a　condenser　or　the　atmosphere；　and　that　the　best　results　in　any　actual　engine　would　be　attained　by　carrying　expansion　to　the　furthest　possible　limit；　or；　in　practice；　by　the　application　of　a　regenerator。　　Anxious　to　realise　his　theories　further；　he　constructed　a　twenty　horse…power　engine　on　the　regenerative　plan；　and　exhibited　it　at　the　Paris　Universal　Exhibition　of　1855；　but；　not　realising　his　expectations；　he　　substituted　for　it　another　of　seven…horse　power；　made　by　M。　Farcot；　of　Paris；　which　was　found　to　work　with　considerable　economy。　　The　use　of　superheated　steam；　however；　still　proved　a　drawback；　and　the　Siemens　engine　has　not　been　extensively　used。

On　the　other　hand；　the　Siemens　water…meter；　which　he　introduced　in　1851；　has　been　very　widely　used；　not　only　in　this　country；　but　abroad。　It　acts　equally　well　under　all　variations　of　pressure；　and　with　a　constant　or　an　intermittent　supply。

Meanwhile　his　brother　Werner　had　been　turning　his　attention　to　telegraphy；　and　the　correspondence　which　never　ceased　between　the　brothers　kept　William　acquainted　with　his　doings。　　In　1844；　Werner；　then　an　officer　in　the　Prussian　army；　was　appointed　to　a　berth　in　the　artillery　workshops　of　Berlin；　where　he　began　to　take　an　interest　in　the　new　art　of　telegraphy。　　In　1845　Werner　patented　his　dial　and　printing　telegraph　instruments；　which　came　into　use　all　over　Germany；　and　introduced　an　automatic　alarm　on　the　same　principle。　　These　inventions　led　to　his　being　made；　in　1846；　a　member　of　a　commission　in　Berlin　for　the　introduction　of　electric　telegraphs　instead　of　semaphores。　　He　advocated　the　use　of　gutta…percha；　then　a　new　material；　for　the　insulation　of　underground　wires；　and　in　1847　designed　a　screw…press　for　coating　the　wires　with　the　gum　rendered　plastic　by　heat。　　The　following　year　he　laid　the　first　great　underground　telegraph　line　from　Berlin　to　Frankfort…on…the…Main；　and　soon　afterwards　left　the　army　to　engage　with　Mr。　Halske　in　the　management　of　a　telegraph　factory　which　they　had　conjointly　established　in　1847。　　In　1852　William　took　an　office　in　John　Street；　Adelphi；　with　a　view　to　practise　as　a　civil　engineer。　　Eleven　years　later；　Mr。　Halske　and　William　Siemens　founded　in　London　the　house　of　Siemens；　Halske　&　Co。；　which　began　with　a　small　factory　at　Millbank；　and　developed　in　course　of　time　into　the　well…known　firm　of　Messrs。　Siemens　Brothers；　and　was　recently　transformed　into　a　limited　liability　company。

In　1859　William　Siemens　became　a　naturalised　Englishman；　and　from　this　time　forward　took　an　active　part　in　the　progress　of　English　engineering　and　telegraphy。　　He　devoted　a　great　part　of　his　time　to　electrical　invention　and　research；　and　the　number　of　telegraph　apparatus　of　all　sortstelegraph　cables；　land　lines；　and　their　accessorieswhich　have　emanated　from　the　Siemens　Telegraph　Works　has　been　remarkable。　　The　engineers　of　this　firm　have　been　pioneers　of　the　electric　telegraph　in　every　quarter　of　the　globe；　both　by　land　and　sea。　　The　most　important　aerial　line　erected　by　the　fir