an autobiography-第26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！

atus　was　then　plunged　into　a　vessel　of　boiling　water；　or　heated　to　boiling　point；　when　the　total　expansion　of　the　bar　was　measured　by　a　graduated　scale；　as　seen　in　the　annexed　engraving。　By　this　simple　means　the　expansion　of　any　material　might　be　ascertained　under　various　increments　of　heat；　say　from　60deg　to　2l2deg。　It　was　simply　a　thermometer；　the　mass　marking　its　own　expansion。　Dr。　Brewster　was　so　much　pleased　with　the　apparatus　that　he　described　it　and　figured　it　in　the　Edinburgh　Philosophical　Journal；　of　which　he　was　then　editor。

＇Image＇　　The　road　steam…carriage。　　By　James　Nasmyth。

About　the　year　1827；　when　I　was　nineteen　years　old；　the　subject　of　steam　carriages　to　run　upon　common　roads　occupied　considerable　attention。　　Several　engineers　and　mechanical　schemers　had　tried　their　hands；　but　as　yet　no　substantial　results　had　come　of　their　attempts　to　solve　the　problem。　　Like　others；　I　tried　my　hand。　　Having　made　a　small　working　model　of　a　steam…carriage；　I　exhibited　it　before　the　members　of　the　Scottish　Society　of　Arts。　　The　performance　of　this　active　little　machine　was　so　gratifying　to　the　Society　that　they　requested　me　to　construct　one　of　such　power　as　to　enable　four　or　six　persons　to　be　conveyed　along　the　ordinary　roads。　　The　members　of　the　Society；　in　their　individual　capacity；　subscribed　#60；　which　they　placed　in　my　hands　as　the　means　for　carrying　out　their　project。

I　accordingly　set　to　work　at　once。　　I　had　the　heavy　parts　of　the　engine　and　carriage　done　at　Anderson's　foundry　at　Leith。　　There　was　in　Anderson's　employment　a　most　able　general　mechanic　named　Robert　Maclaughlan；　who　had　served　his　time　at　Carmichaels'　of　Dundee。　Anderson　possessed　some　excellent　tools；　which　enabled　me　to　proceed　rapidly　with　the　work。　　Besides；　he　was　most　friendly；　and　took　much　delight　in　being　concerned　in　my　enterprise。　　This　〃big　job〃　was　executed　in　about　four　months。　　The　steam…carriage　was　completed　and　exhibited　before　the　members　of　the　Society　of　Arts。　　Many　successful　trials　were　made　with　it　on　the　queensferry　Road；　near　Edinburgh。　The　runs　were　generally　of　four　or　five　miles；　with　a　load　of　eight　passengers　sitting　on　benches　about　three　feet　from　the　ground。

The　experiments　were　continued　for　nearly　three　months；　to　the　great　satisfaction　of　the　members。　　I　may　mention　that　in　my　steam…carriage　I　employed　the　waste　steam　to　create　a　blast　or　draught　by　discharging　it　into　the　short　chimney　of　the　boiler　at　its　lowest　part；　and　found　it　most　effective。　　I　was　not　at　that　time　aware　that　George　Stephenson　and　others　had　adopted　the　same　method；　but　it　was　afterwards　gratifying　to　me　to　find　that　I　had　been　correct　as　regards　the　important　uses　of　the　steam　blast　in　the　chimney。　　In　fact；　it　is　to　this　use　of　the　waste　steam　that　we　owe　the　practical　success　of　the　locomotive…engine　as　a　tractive　power　on　railways；　especially　at　high　speeds。

The　Society　of　Arts　did　not　attach　any　commercial　value　to　my　steam　road…carriage。　　It　was　merely　as　a　matter　of　experiment　that　they　had　invited　me　to　construct　it。　　When　it　proved　successful　they　made　me　a　present　of　the　entire　apparatus。　　As　I　was　anxious　to　get　on　with　my　studies；　and　to　prepare　for　the　work　of　practical　engineering；　I　proceeded　no　further。　　I　broke　up　the　steam…carriage　and　sold　the　two　small　high…pressure　engines；　provided　with　a　compact　and　strong　boiler；　for　#67；　a　sum　which　more　than　defrayed　all　the　expenses　of　the　construction　and　working　of　the　machine。

I　still　continued　to　make　investigations　as　to　the　powers　and　capabilities　of　the　steam…engine。　　There　were　numerous　breweries；　distilleries；　and　other　establishments；　near　Edinburgh；　where　such　engines　were　at　work。　　As　they　were　made　by　different　engineers；　I　was　desirous　of　seeing　them　and　making　sketches　of　them；　especially　when　there　was　any　special　peculiarity　in　their　construction。　　I　found　this　a　most　favourite　and　instructive　occupation。　　The　engine　tenters　became　very　friendly　with　me；　and　they　we　re　always　glad　to　see　me　interested　in　them　and　their　engines。　　They　were　especially　delighted　to　see　me　make　〃drafts；〃　as　they　called　my　sketches；　of　the　engines　under　their　charge。

My　father　sometimes　feared　that　my　too　close　and　zealous　application　to　engineering　work　might　have　a　bad　effect　upon　my　health。　　My　bedroom　work　at　brass　casting；　my　foundry　work　at　the　making　of　steam…engines；　and　my　studies　at　the　University　classes；　were　perhaps　too　much　for　a　lad　of　my　age；　just　when　I　was　in　the　hobbledehoy　statebetween　a　boy　and　a　man。　　Whether　his　apprehensions　were　warranted　or　not；　it　did　so　happen　that　I　was　attacked　with　typhus　fever　in　1828；　a　disease　that　was　then　prevalent　in　Edinburgh。　　I　had　a　narrow　escape　from　its　fatal　influence。　　But　thanks　to　my　good　constitution；　and　to　careful　nursing；　I　succeeded　in　throwing　off　the　fever；　and　after　due　time　recovered　my　usual　health　and　strength。

In　the　course　of　my　inspection　of　the　engines　made　by　different　makers；　I　was　impressed　with　the　superiority　of　those　made　by　the　Carmichaels　of　Dundee。　　They　were　excellent　both　in　design　and　in　execution。　I　afterwards　found　that　the　Carmichaels　were　among　the　first　of　the　Scottish　engine　makers　who　gave　due　attention　to　the　employment　of　improved　mechanical　tools；　with　the　object　of　producing　accurate　work　with　greater　ease；　rapidity；　and　economy；　than　could　possibly　be　effected　by　the　hand　labour　of　even　the　most　skilful　workmen。　　I　was　told　that　the　cause　of　the　excellence　of　the　Carmichaels'　work　was　not　only　in　the　ability　of　the　heads　of　the　firm；　but　in　their　employment　of　the　best　engineers'　tools。　　Some　of　their　leading　men　had　worked　at　Maudslay's　machine　shop　in　London；　the　fame　of　which　had　already　reached　Dundee；　and　Maudslay's　system　of　employing　machine　tools　had　been　imported　into　the　northern　steam　factory。

I　had　on　many　occasions；　when　visiting　the　works　where　steam…engines　were　employed；　heard　of　the　name　and　fame　of　Maudslay。　　I　was　told　that　his　works　were　the　very　centre　and　climax　of　all　that　was　excellent　in　mechanical　workmanship。　　These　reports　built　up　in　my　mind；　at　this　early　period　of　my　aspirations；　an　earnest　and　hopeful　desire　that　I　might　some　day　get　a　sight　of　Maudslay's　celebrated　works　in　London。　In　course　of　time　it　developed　into　a　passion。　　I　will　now　proceed　to　show　how　my　inmost　desires　were　satisfied。


CHAPTER　7。　　Henry　Maudslay；　London

The　chief　object　of　my　ambition　was　now　to　be　taken　on　at　Henry　Maudslay's　works　in　London。　　I　had　heard　so　much　of　his　engineering　work；　of　his　assortment　of　machine…making　tools；　and　of　the　admirable　organisation　of　his　manufactory；　that　I　longed　to　obtain　employment　there。　　I　was　willing　to　labour；　in　however　humble　a　capacity；　in　that　far…famed　workshop。

I　was　aware　that　my　father　had　not　the　means　of　paying　the　large　premium　required　for　placing　me　as　an　apprentice　at　Maudslay's　works。　I　was　also　informed　that　Maudslay　had　ceased　to　take　pupils。　After　experience；　he　found　that　the　premium　apprentices　caused　him　much　annoyance　and　irritation。　　They　came　in　〃gloves；〃　their　attendance　was　irregular；　they　spread　a　bad　example　amongst　the　regular　apprentices　and　workmen；　and　on　the　whole　they　were　found　to　be　very　disturbing　elements　in　the　work　of　the　factory。

It　therefore　occurred　to　me　that；　by　showing　some　specimens　of　my　work　and　drawings；　I　might　be　able　to　satisfy　Mr。　Maudslay　that　I　was　not　an　amateur；　but　a　regular　working　engineer。　　With　this　object　I　set　to　work；　and　made　with　special　care　a　most　complete　working　model　of　a　high…pressure　engine。　　The　cylinder　was　2　inches　diameter；　and　the　stroke　6　inches。　　Every　part　of　the　engine；　including　the　patterns；　the　castings；　the　forgings；　were　the　results　of　my　own　individual　handiwork。　　I　turned　out　this　sample　of　my　ability　as　an　engineer　workman　in　such　a　style　as　even　now　I　should　be　proud　to　own。

In　like　manner　I　executed　several　specimens　of　my　ability　as　a　mechanical　draughtsman；　for　I　knew　that　Maudslay　would　thoroughly　understand　my　ability　to　work　after　a　plan。　　Mechanical　drawing　is　the　alphabet　of　the　engineer。　　Without　this　the　workman　is　merely　a　〃hand。〃　With　it　he　indicates　the　possession　of　〃a　head〃　I　also　made　some　samples　of　my　skill　in　hand…sketching　of　machines；　and　parts　of　machines；　in　perspectivethat　is；　as　such　objects　really　appear　when　set　before　us　in　their　natural　aspect。　　I　was　the　more　desirous　of　exhibiting　the　ability　which　I　possessed　in　mechanical　draughtsmanship；　as　I　knew　it　to　be　a　somewhat　rare　and　much…valued　acquirement。　It　was　a　branch　of　delineative　art　that　my　father　had　carefully　taught　me。　Throughout　my　professional　life　I　have　found　this　art　to　be　of　the　utmost　practical　value。

Having　thus　provided　myself　with　such　visible　and　tangible　evidences　　of　my　capabilities　as　a　young　engineer；　I　carefully　packed　up　my　　working　model　and　drawings；　and　prepared　to　start　for　London。　On　the　19th　of　May　1829；　accompanied　by　my　father；　I　set　sail　by　the　Leith　smack　Edinburgh　Castle；　Captain　Orr；　master。　　After　a　pleasant　voyage　of　four　days　we　reached　the　mouth　of　the　Thames。　　We　sailed　up　from　the　Nore　on　Saturday　afternoon；　lifted　up；　as　it　were；　by　the　tide；　for　it　was　almost　a　dead　calm　the　whole　way。

The　si