第49章
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  AsMr。CadwalladrDaviesobservedatthebanquet,whichtookplaceonthefollowingday:“TheestablishmentofthenewinstitutionwillmarkthedawnofanewerainthehistoryoftheWelshpeople。Helookedtoit,notonlyasameansofimpartingacademicalknowledgetothestudentswithinitswalls,butalsoasameansofraisingtheintellectualandmoraltoneofthewholepeople。TheywerefondofquotingthesayingofagreatEnglishwriter,thattherewassomethingGrecianintheCelticrace,andthattheCelticwastherefiningelementintheBritishcharacter;butsuchremarks,oftenaccompaniedastheywerewithoffensivecomparisonsfromEisteddfodplatforms,wouldinfuturebeputtothetest,fortheywould,withtheirneweducationalmachinery,beplacedonafootingofperfectequalitywiththeScotchandtheIrishpeople。“

  AndheremustcometoanendthecharacterhistoryofmyautumntourinIreland,Scotland,Yorkshire,andWales。Ihadnottheremotestintentionwhensettingoutofcollectinginformationandwritingdownmyrecollectionsofthejourney。ButthepersonsI

  met,andtheinformationIreceived,wereofnosmallinterest——atleasttomyself;andItrustthatthereaderwillderiveasmuchpleasurefromperusingmyobservationsasIhavehadincollectingandwritingthemdown。IdothinkthattheremarkablepersonswhosehistoryandcharactersIhaveendeavoured,howeverbriefly,tosketch,willbefoundtoaffordmanyvaluableandimportantlessonsofSelf-Help;andtoillustratehowthemoralandindustrialfoundationsofacountrymaybebuiltupandestablished。

  FootnotesforChapterXII。

  [1]A“poet,“whodatesfrom“NewYork,March1883,“haspublishedsevenstanzas,entitled“ChangehereforBlairgowrie,“

  fromwhichwetakethefollowing:——

  “Fromearlymorntilllateate’en,John’shonestfaceistobeseen,Bustlingaboutthetrainsbetween,Be’tsunshineorbe’tshowery;

  Andaseachonestopsathisdoor,Hegreetsitwiththewell-knownroarOf’ChangehereforBlairgowrie。’

  EvenwhenthestillanddrowsynightHasdrawnthecurtainsofoursight,John’swatchfuleyesbecomemorebright,Andtakeanotherglow’rayeThro’yonbluedomeofsparklingstarsWhereVenusbrightandruddyMarsShinedownuponBlairgowrie。

  Hekenseachjinkin’comet’strack,Andwhenit’slikelytocomeback,Whentheyhavetails,andwhentheylack——

  Inheaventhewaggishpoweraye;

  WhenJupiter’sbeltbucklehings,AndthePyxmarkonSaturn’srings,HeseesfromnearBlairgowrie。“

  TheObservatory,No。61,p。146;andNo。68,p。371。

  InanarticleonthesubjectintheDundeeEveningTelegraph,Mr。Robertsonobserves:“Ifourfinitemindsweremorecapableofcomprehension,whatagloriousviewofthegrandeuroftheDeitywouldbedisplayedtousinthecontemplationofthecentreandsourceoflightandheattothesolarsystem。Theforcerequisitetopoursuchcontinuousfloodstotheremotestpartsofthesystemmusteverbafflethemindofmantograsp。Butwearenottositdowninindolence:ourdutyistoinquireintoNature’sworks,thoughwecanneverexhaustthefield。OurmindscannotimaginemotionwithoutsomePowermovingthroughthemediumofsomesubordinateagency,everactingonthesun,tosendsuchfloodsoflightandheattoourotherwisecoldanddarkterrestrialball;butitistheoverwhelmingmagnitudeofsuchpowerthatweareincapableofcomprehending。Theagencynecessarytothrowoutthefloodsofflameseenduringthefewmomentsofatotaleclipseofthesun,andthepowerrequisitetoburstopenacavityinitssurface,suchascouldentirelyengulphourearth,willeversetallthethinkingcapacityofmanatnought。“

  TheObservatory,Nos。34,42,45,49,and58。

  WeregrettosaythatSheriffBarclaydiedafewmonthsago,greatlyrespectedbyallwhoknewhim。

  SirE。DenisonBeckett,inhisRudimentaryTreatiseonclocksandWatchesandBells,hasgivenaninstanceorthetelescope-drivingclock,inventedbyMr。Cookep。213。

  J。NormanLockyer,F。R。S——Stargazing,PastandPresent,p。

  302。

  Thisexcellentinstrumentisnowinthepossessionofmyson-in-law,Dr。Hartree,ofLeigh,nearTunbridge。

  AninterestingaccountofMr。AlvanClarkisgiveninProfessorNewcomb’s’PopularAstronomy,’p。137。

  AphotographicrepresentationofthisremarkabletelescopeisgivenasthefrontispiecetoMr。Lockyer’sStargazing,PastandPresent;andafulldescriptionoftheinstrumentisgiveninthetextofthesamework。Thisrefractingtelescopedidnotlongremainthelargest。Mr。AlvanClarkwascommissionedtoerectalargerequatorialforWashingtonObservatory;theobject-glasstheroughdisksofwhichwerealsofurnishedbyMessrs。ChanceofBirminghamexceedinginaperturethatofMr。

  Cooke’sbyonlyoneinch。ThiswasfinishedandmountedinNovember,1873。AnotherinstrumentofsimilarsizeandpowerwasmanufacturedbyMr。ClarkfortheUniversityofVirginia。Buttheseinstrumentsdidnotlongmaintaintheirsupremacy。In1881,Mr。HowardGrubb,ofDublin,manufacturedastilllargerinstrumentfortheAustrianGovernment——theobject-glassbeingoftwenty-seveninchesaperture。ButMr。AlvanClarkwasnottobebeaten。In1882,hesuppliedtheRussianGovernmentwiththelargestrefractingtelescopeinexistencetheobject-glassbeingofthirtyinchesdiameter。Eventhis,however,istobesurpassedbythelenswhichMr。ClarkhasinhandfortheLickObservatoryCalifornia,whichistohaveaclearapertureofthreefeetindiameter。

  [11]Sincetheabovepassagewaswrittenandintype,IhaveseeninSeptember1884thereflectingtelescopereferredtoatpp。

  357-8。Itwasmountedonitscast-ironequatorialstand,andatworkinthefieldadjoiningthevillagegreenatBainbridge,Yorkshire。Themirrorofthetelescopeis8inchesindiameter;

  itsfocallength,5feet;andthetubeinwhichitismounted,about6feetlong。Theinstrumentseemedtometohaveanexcellentdefiningpower。

  ButMr。Lancaster,likeeveryeagerastronomer,isanxiousforfurtherimprovements。Heconsiderstheachromatictelescopethekingofinstruments,andisnowengagedintestingconvexopticalsurfaces,withaviewtoachievingatelescopeofthatdescription。Thechiefdifficultyistheheavychargeforthecircularblocksofflintglassrequisitefortheworkwhichhemeditates。“That,“hesays,“isthegreatdifficultywithamateursofmyclass。“Hehas,however,alreadycontrivedandconstructedamachineforgrindingandpolishingthelensesinanaccurateconvexform,anditworksquitesatisfactorily。Mr。

  Lancastermakeshisowntools。Fromtherawmaterial,whetherofglassorsteel,heproducestheworkrequired。Astotools,allthatherequiresisabarofsteelandfire;hisfertilebrainandbusyhandsdotherest。Ilookedintothelittleworkshopbehindhissitting-room,andfounditfullofingeniousadaptations。Theturninglatheoccupiesaconsiderablepartofit;butwhenherequiresmorespace,thevillagesmithwithhisstithy,andthemillerwithhiswater-power,arealwaysreadytohelphim。Histools,thoughnotshowy,areeffective。Hisbestlensesaremadebyhimself:thosewhichhebuysarenottobedependedupon。ThebestflintglassisobtainedfromParisinblocks,whichhedivides,grinds,andpolishestoperfectform。

  Iwasattractedbyanewlymademachine,placedonatableinthesitting-room;andoninquiryfoundthatitsobjectwastogrindandpolishlenses。Mr。Lancasterexplainedthatthedifficultytobeovercomeinagoodmachine,istomaketheemerycutthesurfaceequallyfromcentretoedgeofthelens,sothatthelenswillneitherlengthennorshortenthecurveduringitsproduction。Toquotehiswords:“Thisreallyinvolvestheproblemofthe’threebodies,’ordisturbingforcessocelebratedindynamicalmathematics,anditisfurthercomplicatedbyanotherquantity,the’coefficientofattrition,’orworkdonebythegrindingmaterial,aswellasthemischiefdonebycapillaryattractionandnodalpointsofsuperimposedcurvesinthepathofthetool。Thesecomplicationstendtocauseringsorwavesofunequalwearinthesurfaceoftheglass,andruinthedefiningpowerofthelens,whichdependsupontheuniformityofitscurve。Astheoutcomeofmuchpracticalexperiment,combinedwithmathematicalresearch,Isettledupontheratioofspeedbetweenthesheaveofthelens-toolguideandtheturn-table;

  betweenwhoselimitsthepracticalequalizationofwearorcutoftheemerymightwiththegreaterfacilitybeadjusted,bymeansofvaryingthestrokeandeccentricityofthetool。Astheresultoftheseconsiderationsintheconstructionofthemachine,thesurfaceoftheglass’comesup’regularlyalloverthelens;andthepolishingonlytakesafewminutes’work——thuskeepingthetruthofsurfacegainedbyusingarigidtool。“

  Themachineinquestionconsistsofarevolvingsheaveorring,withaslidingstripacrossitsdiameter;thesaidstriphavingaslotandclampingscrewatoneend,andaholetowardstheother,throughwhichpassestheaxisofthetoolusedinformingthelens,——theslotinthestripallowingthetooltogiveanystrokefrom0to1。25inch。Thelensiscarriedonarevolvingturn-table,withanarrangementtoallowtheaxisofthelenstocoincidewiththeaxisofthetable。Theratioofspeedbetweenthesheaveandturn-tableisarrangedbybeltandproperlysizedpulleys,andthewholecanbedriveneitherbyhandorbypower。

  Thesheavemerelyservesasaguidetothetoolinitspath,andthelensmayeitherbeworkedontheturn-tableoruponachuckattachedtothetoolrod。Theworkuponthelensisthustoagreatextentindependentoftheerrorofthemachinethroughshaking,orbadfitting,orwear;andtheonlypartofthemachinewhichrequiresreallyfirst-classworkistheaxisoftheturn-table,whichinthismachineisaconicalbearingattop,withsteelcentrebelow,——thebearingturned,hardened,andthengrounduptrue,andruninanti-frictionmetal。Otherdetailsmightbegiven,buttheseareprobablyenoughforpresentpurposes。Wehope,atsomefuturetime,foraspecialdetailofMr。Lancaster’sinterestinginvestigations,fromhisownmindandpen。

  [12]ThetranslationsaremadebyW。CadwalladrDavies,Esq。

  [13]ThisevidencewasgivenbyMr。W。CadwalladrDaviesonthe28thOctober,1880。

  End

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