an autobiography-第60部分

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Way。　　It　revealed　such　countless　multitudes　of　stars　that　I　had　only　to　sit　before　the　eyepiece；　and　behold　the　endless　procession　of　these　glorious　objects　pass　before　me。　The　motion　of　the　earth　assisted　in　changing　this　scene　of　inexpressible　magnificence；　which　reached　its　climax　when　some　object　such　as　the　〃Cluster　in　Hercules〃　came　into　sight。　　The　component　stars　are　so　crowded　together　there　as　to　give　the　cluster　the　appearance　of　a　gray　spot；　but　when　examined　with　a　telescope　of　large　aperture；　it　becomes　resolved　into　such　myriads　of　stars　as　to　defy　all　attempts　to　count　them。　　Nothing　can　convey　to　the　mind；　in　so　awful　and　impressive　a　manner；　the　magnificent　and　infinite　extent　of　Creation；　and　the　inconceivable　power　of　its　Creator！

I　had　already　a　slight　acquaintance　with　Astronomy。　　My　father　had　implanted　in　me　the　first　germs。　　He　was　a　great　admirer　of　that　sublimest　of　sciences。　　I　had　obtained　a　sufficient　amount　of　technical　knowledge　to　construct　in　1827　a　small　but　very　effective　reflecting　telescope　of　six　inches　diameter。　　Three　years　later　I　initiated　Mr。　Maudslay　into　the　art　and　mystery　of　making　a　reflecting　telescope。　I　then　made　a　speculum　of　ten　inches　diameter；　and　but　for　the　unhappy　circumstance　of　his　death　in　1831；　it　would　have　been　mounted　in　his　proposed　observatory　at　Norwood。　　After　I　had　settled　down　at　Fireside；　Patricroft；　I　desired　to　possess　a　telescope　of　considerable　power　in　order　to　enjoy　the　tranquil　pleasure　of　surveying　the　heavens　in　their　impressive　grandeur　at　night。

As　I　had　all　the　means　and　appliances　for　casting　specula　at　the　factory；　I　soon　had　the　felicity　of　embodying　all　my　former　self…acquired　skill　in　this　fine　art　by　producing　a　very　perfect　casting　of　a　ten…inch　diameter　speculum。　　The　alloy　consisted　of　fifteen　parts　of　pure　tin　and　thirty…two　parts　of　pure　copper；　with　one　part　of　arsenic。　　It　was　cast　with　perfect　soundness；　and　was　ground　and　polished　by　a　machine　which　I　contrived　for　the　purpose。　The　speculum　was　so　brilliant　that　when　my　friend　William　Lassell　saw　it；　he　said　〃it　made　his　mouth　water。〃　　It　was　about　this　time　（1840）　that　I　had　the　great　happiness　of　becoming　acquainted　with　Mr。　Lassell；*　　＇footnote。。。　Mr。　Lassell　was　a　man　of　superb　powers。　　Like　many　others　who　have　done　so　much　for　astronomy；　he　started　as　an　amateur。　He　was　first　apprenticed　to　a　merchant　at　Liverpool。　　He　then　began　business　as　a　brewer。　　Eventually　he　devoted　himself　to　astronomy　and　astronomical　mechanics。　　When　in　his　twenty…first　year　he　began　constructing　reflecting　telescopes　for　himself。　　He　proceeded　to　make　a　Newtonian　of　nine　inches　aperture；　which　he　erected　in　an　observatory　at　his　residence　near　Liverpool；　happily　named　〃Starfield。〃　With　this　instrument　he　worked　diligently；　and　detected　the　sixth　star　in　the　trapezium　of　Orion。　　In　1844　he　conceived　the　bold　idea　of　constructing　a　reflector　of　two　feet　aperture；　and　twenty　feet　focal　length；　to　be　mounted　equatorially。　　Sir　John　Herschel；　in　mentioning　Mr。　Lassell's　work；　did　me　the　honour　of　saying　〃that　in　Mr　Nasmyth　he　was　fortunate　to　find　a　mechanist　capable　of　executing　in　the　highest　perfection　all　his　conceptions；　and　prepared　by　his　own　love　of　astronomy　and　practical　acquaintance　with　astronomical　observations；　and　with　the　construction　of　specula；　to　give　them　their　full　effect。〃　With　this　fine　instrument　Mr。　Lassell　discovered　the　satellite　of　Neptune。　　He　also　discovered　the　eighth　satellite　of　Saturn；　of　extreme　minuteness；　as　well　as　two　additional　satellites　of　Uranus。　But　perhaps　his　best　work　was　done　at　Malta　with　a　much　larger　telescope；　four　feet　in　aperture；　and　thirty…seven　feet　focus；　erected　there　in　1861。　　He　remained　at　Malta　for　three　years；　and　published　a　catalogue　of　600　new　nebulae；　which　will　be　found　in　the　Memoirs　of　the　Royal　Astronomical　Society。　　One　of　his　curious　sayings　was；　〃I　have　had　a　great　deal　to　do　with　opticians；　some　of　themlike　Cooke　of　Yorkare　really　opticians；　but　the　greater　number　of　them　are　merely　shopticians！〃　　。。。＇　and　profiting　by　his　devotion　to　astronomical　pursuits　and　his　profound　knowledge　of　the　subject。　　He　had　acquired　much　technical　skill　in　the　construction　of　reflecting　telescopes；　and　the　companionship　between　us　was　thus　rendered　very　agreeable。　　There　was　an　intimate　exchange　of　opinions　on　the　subject；　and　my　friendship　with　him　continued　during　forty　successive　years。　　I　was　perhaps　a　little　ahead　of　him　in　certain　respects。　　I　had　more　practical　knowledge　of　casting；　for　I　had　begun　when　a　boy　in　my　bedroom　at　Edinburgh。　　In　course　of　time　I　contrived　many　practical　〃dodges〃　（if　I　may　use　such　a　word）；　and　could　nimbly　vault　over　difficulties　of　a　special　kind　which　had　hitherto　formed　a　barrier　in　the　way　of　amateur　speculum　makers　when　fighting　their　way　to　a　home…made　telescope。　　I　may　mention　that　I　know　of　no　mechanical　pursuit　in　connection　with　science；　that　offers　such　an　opportunity　for　practising　the　technical　arts；　as　that　of　constructing　from　first　to　last　a　complete　Newtonian　or　Gregorian　Reflecting　Telescope。　Such　an　enterprise　brings　before　the　amateur　a　succession　of　the　most　interesting　and　instructive　mechanical　arts；　and　obliges　the　experimenter　to　exercise　the　faculty　of　delicate　manipulation。　If　I　were　asked　what　course　of　practice　was　the　best　to　instil　a　true　taste　for　refined　mechanical　work；　I　should　say；　set　to　and　make　for　yourself　from　first　to　last　a　reflecting　telescope　with　a　metallic　speculum。　　Buy　nothing　but　the　raw　material；　and　work　your　way　to　the　possession　of　a　telescope　by　means　of　your　own　individual　labour　and　skill。　　If　you　do　your　work　with　the　care；　intelligence；　and　patience　that　is　necessary；　you　will　find　a　glorious　reward　in　the　enhanced　enjoyment　of　a　night　with　the　heavensall　the　result　of　your　own　ingenuity　and　handiwork。　　It　will　prove　a　source　of　abundant　pleasure　and　of　infinite　enjoyment　for　the　rest　of　your　life。

I　well　remember　the　visit　I　received　from　my　dear　friend　Warren　de　la　Rue　in　the　year　1840。　　I　was　executing　some　work　for　him　with　respect　to　a　new　process　which　he　had　contrived　for　the　production　of　white　lead。　I　was　then　busy　with　the　casting　of　my　thirteen…inch　speculum。　He　watched　my　proceedings　with　earnest　interest　and　most　careful　attention。　　He　told　me　many　years　after；　that　it　was　the　sight　of　my　special　process　of　casting　a　sound　speculum　that　in　a　manner　caused　him　to　turn　his　thoughts　to　practical　astronomy；　a　subject　in　which　he　has　exhibited　such　noble　devotion　as　well　as　masterly　skill。　　Soon　after　his　visit　I　had　the　honour　of　casting　for　him　a　thirteen…inch　speculum；　which　he　afterwards　ground　and　polished　by　a　method　of　his　own。　He　mounted　it　in　an　equatorial　instrument　of　such　surpassing　excellence　as　enabled　him；　aided　by　his　devotion　and　pure　love　of　the　subject；　to　record　a　series　of　observations　and　results　which　will　hand　his　name　down　to　posterity　as　one　of　the　most　faithful　and　patient　of　astronomical　observers。

＇Image＇　　Fireside；　Patricroft。　　After　a　drawing　by　James　Nasmyth

But　to　return　to　my　own　little　work　at　Patricroft。　　I　mounted　my　ten…inch　home…made　reflecting　telescope；　and　began　my　survey　of　the　heavens。　　Need　I　say　with　what　exquisite　delight　the　harmony　of　their　splendour　filled　me。　　I　began　as　a　learner；　and　my　learning　grew　with　experience。　　There　were　the　prominent　stars；　the　planets；　the　Milky　Way　with　thousands　of　far…off　sunsto　be　seen。　　My　observations　were　at　first　merely　general；　by　degrees　they　became　particular。　I　was　not　satisfied　with　enjoying　these　sights　myself；　I　made　my　friends　and　neighbours　sharers　in　my　pleasure；　and　some　of　them　enjoyed　the　wonders　of　the　heavens　as　much　as　I　did。

In　my　early　use　of　the　telescope　I　had　fitted　the　speculum　into　a　light　square　tube　of　deal　to　which　the　eye…piece　was　attached；　so　as　to　have　all　the　essential　parts　of　the　telescope　combined　together　in　the　most　simple　and　portable　form。　　I　had　often　to　remove　it　from　place　to　place　in　my　small　garden　at　the　side　of　the　Bridgewater　Canal；　in　order　to　get　it　clear　of　the　trees　and　branches　which　intercepted　some　object　in　the　heavens　which　I　wished　to　see。　　How　eager　and　enthusiastic　I　was　in　those　days！　　Sometimes　I　got　out　of　bed　in　the　clear　small　hours　of　the　morning；　and　went　down　to　the　garden　in　my　night…shirt。　　I　would　take　the　telescope　in　my　arms　and　plant　it　in　some　suitable　spot；　where　I　might　get　a　peep　at　some　special　planet　or　star　then　above　the　horizon。

It　became　bruited　about　that　a　ghost　was　seen　at　Patricroft！　A　barge　was　silently　gliding　along　the　canal　near　midnight；　when　the　boatman　suddenly　saw　a　figure　in　white。　〃It　moved　among　the　trees　with　a　coffin　in　its　arms！〃　The　apparition　was　so　sudden　and　strange　that　he　immediately　concluded　that　it　was　a　ghost。　　The　weird　sight　was　reported　at　the　stations　along　the　canal；　and　also　at　Wolverhampton；　which　was　the　boatman's　headquarters。　　He　told　the　people　at　Patricroft　on　his　return　journey　what　he　had　seen；　and　great　was　the　excitement　produced。　　The　place　was　haunted：　　there　was　no　doubt　about　it！　　After　all；　the　rumour　was　founded　on　fact；　for　the　ghost　was　merely　myself　in　my　night…shirt；　and　the　coffin　was　my　telescope；　which　I　was　quietly　shifting　from　one　place　to　another　in　order　to　get　a　clearer　sight　of　the　heavens　at　midnight。

My　ambition　expanded。　　I　now　resolved　to　construct　a　reflecting　telescope　of　considerably　greater　power　than　that　which　I　possessed。　I　made　one　of　twenty　inches　diameter；　and　mounted　it　on　a　very　simple　plan；　thus　removing　many　of　the　inconveniences　and　even　personal　risks　that　attend　the　use　of　such　instruments。　　（For　illustration　of　the　plan　of　mounting　a　large　telescope；　see　p。　338）　It　had　been　necessary　to　mount　steps　or　ladders　to　get　at　the　eyepiece；　especially　when　the　objects　to　be　observed　were　at　a　high　elevation　above　the　horizon。　I　now　prepared　to　do　some　special　work　with　this　instrument。　In　1842　I　began　my　systematic　researches　upon　the　Moon。　　I　carefully　and　minutely　scrutinised　the　marvellous　details　of　its　surface；　a　pursuit　which　I　continued　for　many　years；　and　still　continue　with　ardour　until　this　day。　　My　method　was　as　follows：　

I　availed　myself　of　every　favourable　opportunity　for　ca