TradebeingveryslackinGlasgowatthetime,Clement,afteraboutayear’sstayintheplace,acceptedasituationwithMessrs。Leys,Masson,andCo。,ofAberdeen,withwhomhebeganataguineaandahalfaweek,fromwhichhegraduallyrosetotwoguineas,andultimatelytothreeguineas。Hisprincipalworkconsistedindesigningandmakingpower-loomsforhisemployers,andfittingthemupindifferentpartsofthecountry。Hecontinuedtodevotehimselftothestudyofpracticalmechanics,andmademanyimprovementsinthetoolswithwhichheworked。WhileatGlasgowhehadmadeanimprovedpairofdie-stocksforscrews;and,atAberdeen,hemadeaturning-lathewithaslidingmandrillandguide-screws,forcuttingscrews,furnishedalsowiththemeansforcorrectingguide-screws。Inthesamemachineheintroducedasmallsliderest,intowhichhefixedthetoolforcuttingthescrews,——havingneverbeforeseenasliderest,thoughitisveryprobablehemayhaveheardofwhatMaudslayhadalreadydoneinthesamedirection。Clementcontinuedduringthisperiodofhislifeanindustriousself-cultivator,occupyingmostofhissparehoursinmechanicalandlandscapedrawing,andinvariousstudies。AmongthepapersleftbehindhimwefindatickettoacourseofinstructiononNaturalPhilosophygivenbyProfessorCoplandintheMarischalCollegeatAberdeen,whichClementattendedinthesessionof1812-13;andwedonotdoubtthatourmechanicwasamongthemostdiligentofhispupils。Towardstheendof1813,aftersavingabout100L。outofhiswages,ClementresolvedtoproceedtoLondonforthepurposeofimprovinghimselfinhistradeandpushinghiswayintheworld。ThecoachbywhichhetravelledsethimdowninSnowHill,Holborn;andhisfirstthoughtwasoffindingwork。Hehadnofriendintowntoconsultonthematter,sohemadeinquiryofthecoach-guardwhetherheknewofanypersoninthemechanicallineinthatneighbourhood。Theguardsaid,”Yes;therewasAlexanderGalloway’sshowshop,justroundthecorner,andheemployedalargenumberofhands。”Runningroundthecorner,ClementlookedinatGalloway’swindow,throughwhichhesawsomelathesandotherarticlesusedinmachineshops。Nextmorninghecalledupontheowneroftheshoptoaskemployment。”Whatcanyoudo?”askedGalloway。”Icanworkattheforge,”saidClement。”Anythingelse?””Icanturn。””Whatelse?””Icandraw。””What!”
saidGalloway,”canyoudraw?ThenIwillengageyou。”Amanwhocoulddraworworktoadrawinginthosedayswasregardedasasuperiorsortofmechanic。ThoughGallowaywasoneoftheleadingtradesmenofhistime,andhadexcellentopportunitiesforadvancement,hemissedthemall。AsClementafterwardssaidofhim,”Hewasonlyamouthingcommon-councilman,theheightofwhoseambitionwastobeanalderman;”and,likemostcorporationcelebrities,heheldalowrankinhisownbusiness。Heveryrarelywentintohisworkshopstosuperintendordirecthisworkmen,leavingthistohisforemen——asufficientindicationofthecausesofhisfailureasamechanic。*
[footnote……
OnoneoccasionGallowayhadacast-ironroofmadeforhisworkshop,soflatandsoindependentoftiesthatthewonderwasthatitshouldhavestoodanhour。OnedayPeterKeir,anengineermuchemployedbythegovernment——acleverman,thoughsomewhateccentric——wastakenintotheshopbyGallowaytoadmirethenewroof。Keir,onglancingupatit,immediatelyexclaimed,”Comeoutside,andletusspeakaboutitthere!”AllthathecouldsaytoGallowayrespectingtheunsoundnessofitsconstructionwasofnoavail。Thefactwasthat,howeverKeirmightargueaboutitsnotbeingabletostand,thereitwasactuallystanding,andthatwasenoughforGalloway。Keirwenthome,hismindfilledwithGalloway’smostunprincipledroof。”Ifthatstands,”saidhetohimself,”allthatIhavebeenlearninganddoingforthirtyyearshasbeenwrong。”Thatnighthecouldnotsleepforthinkingaboutit。InthemorninghestrolledupPrimroseHill,andreturnedhomestillmutteringtohimselfabout”thatroof。””What,saidhiswifetohim,”areyouthinkingofGalloway’sroof?””Yes,saidhe。”Thenyouhaveseenthepapers?””No——whataboutthem?””Galloway’sroofhasfalleninthismorning,andkilledeightortenofthemen!”Keirimmediatelywenttobed,andsleptsoundlytillnextmorning。
OnenteringGalloway’sshop,Clementwasfirstemployedinworkingatthelathe;butfindingthetoolssobadthatitwasimpossibletoexecutesatisfactoryworkwiththem,heatoncewenttotheforge,andbeganmakinganewsetoftoolsforhimself。Theothermen,towhomsuchaproceedingwasentirelynew,cameroundhimtoobservehisoperations,andtheyweremuchstruckwithhismanualdexterity。
Thetoolsmade,heproceededtousethem,displayingwhatseemedtotheotherworkmenanunusualdegreeofenergyandintelligence;andsomeoftheoldhandsdidnothesitatealreadytopronounceClementtobethebestmechanicintheshop。WhenSaturdaynightcameround,theothermenwerecurioustoknowwhatwagesGallowaywouldallowthenewhand;andwhenhehadbeenpaid,theyaskedhim。”Aguinea,”
wasthereply。”Aguinea!Why,youareworthtwoifyouareworthashilling,”saidanoldmanwhocameoutoftherank——anexcellentmechanic,who,thoughcomparativelyworthlessthroughhisdevotiontodrink,knewClement’smoneyvaluetohisemployerbetterthananymanthere;andheadded,”Waitforaweekortwo,andifyouarenotbetterpaidthanthis,Icantellyouofamasterwhowillgiveyouafairerwage。”SeveralSaturdayscameround,butnoadvancewasmadeontheguineaaweek;andthentheoldworkmanrecommendedClementtoofferhimselftoBramahatPimlico,whowasalwaysonthelookoutforfirst-ratemechanics。
Clementactedontheadvice,andtookwithhimsomeofhisdrawings,atsightofwhichBramahimmediatelyengagedhimforamonth;andattheendofthattimehehadgivensomuchsatisfaction,thatitwasagreedheshouldcontinueforthreemonthslongerattwoguineasaweek。Clementwasplacedinchargeofthetoolsoftheshop,andheshowedhimselfsoaptatintroducingimprovementsinthem,aswellasinorganizingtheworkwithaviewtodespatchandeconomy,thatattheendofthetermBramahmadehimahandsomepresent,adding,”ifI
hadsecuredyourservicesfiveyearssince,Iwouldnowhavebeenarichermanbymanythousandsofpounds。”AformalagreementforatermoffiveyearswasthenenteredintobetweenBramahandClement,datedthe1stofApril,1814,bywhichthelatterundertooktofilltheofficeofchief-draughtsmanandsuperintendentofthePimlicoWorks,inconsiderationofasalaryofthreeguineasaweek,withanadvanceoffourshillingsaweekineachsucceedingyearoftheengagement。Thisarrangementprovedofmutualadvantagetoboth。
Clementdevotedhimselfwithincreasedzealtotheimprovementofthemechanicalarrangementsoftheconcern,exhibitinghisingenuityinmanyways,andtaking;agenuineprideinupholdingthecharacterofhismasterforturningoutfirst-classwork。
OnthedeathofBramah,hissonsreturnedfromcollegeandenteredintopossessionofthebusiness。TheyfoundClementtherulingmindthereandgrewjealousofhimtosuchanextentthathissituationbecameuncomfortable;andbymutualconsenthewasallowedtoleavebeforetheexpiryofhistermofagreement。Hehadnodifficultyinfindingemployment;andwasatoncetakenonaschiefdraughtsmanatMaudslayandField’swherehewasofmuchassistanceinproportioningtheearlymarineengines,forthemanufactureofwhichthatfirmwerebecomingcelebrated。Afterashorttime,hebecamedesirousofbeginningbusinessonhisownaccountasamechanicalengineer。HewasencouragedtodothisbytheDukeofNorthumberland,who,beingagreatloverofmechanicsandhimselfacapitalturner,usedoftentovisitMaudslay’s,andthusbecameacquaintedwithClement,whoseexpertnessasadraughtsmanandmechanichegreatlyadmired。Beingamanoffrugalandsoberhabits,alwayskeepinghisexpenditureveryconsiderablywithinhisincome,Clementhadbeenenabledtoaccumulateabout500L。,whichhethoughtwouldbeenoughforhispurpose;andheaccordinglyproceeded,in1817,totakeasmallworkshopinProspectPlace,NewingtonButts,wherehebeganbusinessasamechanicaldraughtsmanandmanufacturerofsmallmachineryrequiringfirst-classworkmanship。
FromthetimewhenhetookhisfirstgratuitouslessonsindrawingfromPeterNicholson,atGlasgow,in1807,hehadbeensteadilyimprovinginthisart,theknowledgeofwhichisindispensabletowhoeveraspirestoeminenceasamechanicalengineer,——untilbygeneralconsentClementwasconfessedtostandunrivalledasadraughtsman。SomeoftheverybestdrawingscontainedintheTransactionsoftheSocietyofArts,fromtheyear1817
downwards,——especiallythoserequiringthedelineationofanyunusuallyelaboratepieceofmachinery,——proceededfromthehandofClement。Insomeofthese,hereachedadegreeoftruthinmechanicalperspectivewhichhasneverbeensurpassed。*
[footnote……
SeemoreparticularlyTheTransactionsoftheSocietyfortheEncouragementofArts,vol。xxxiii。l8l7,atpp。74,l57,l60,175,208
anadmirabledrawing;ofMr。JamesAllen’sTheodolite;vol。xxxvi。
1818,pp。28,176aseriesofremarkableillustrationsofMr。
Clement’sowninventionofanInstrumentforDrawingEllipses;vol。
xliii。1825,containinganillustrationoftheDrawingTableinventedbyhimforlargedrawings;vol。xlvi。1828,containingaseriesofelaborateillustrationsofhisPrizeTurningLathe;andxlviii。1829,containingillustrationsofhisSelf-adjustingDoubleDriverCentreChuck。
Tofacilitatehislabours,heinventedanextremelyingeniousinstrument,bymeansofwhichellipsesofallproportions,aswellascirclesandrightlines,mightbegeometricallydrawnonpaperoroncopper。Hetookhisideaofthisinstrumentfromthetrammelusedbycarpentersfordrawingimperfectellipses;andwhenhehadsucceededinavoidingthecrossingofthepoints,heproceededtoinventthestraight-linemotion。ForthisinventiontheSocietyofArtsawardedhimtheirgoldmedalin1818。Someyearslater,hesubmittedtothesameSocietyhisinventionofastandfordrawingsoflargesize。Hehadexperiencedconsiderabledifficultyinmakingsuchdrawings,andwithhisaccustomedreadinesstoovercomeobstacles,heforthwithsettoworkandbroughtouthisnewdrawing-table。
Aswithmanyotheroriginal-mindedmechanics,inventionbecameahabitwithhim,andbystudyandlabourherarelyfailedinattainingtheobjectwhichhehadbenthisminduponaccomplishing。Indeed,nothingpleasedhimbetterthantohavewhathecalled”atoughjob;”
asitstimulatedhisinventivefaculty,intheexerciseofwhichhetookthehighestpleasure。HencemechanicalschemersofallkindswereaccustomedtoresorttoClementforhelpwhentheyhadfoundanideawhichtheydesiredtoembodyinamachine。Iftherewasanyvalueintheiridea,nonecouldbemorereadythanhetorecogniseitsmerit,andtoworkitintoshape;butifworthless,hespokeouthismindatonce,dissuadingtheprojectorfromwastinguponitfurtherlabourorexpense。
OneoftheimportantbranchesofpracticalmechanicstowhichClementcontinuedthroughlifetodevotehimself,wastheimprovementofself-actingtools,moreespeciallyoftheslide-lathe。Heintroducedvariousimprovementsinitsconstructionandarrangement,untilinhishandsitbecameasnearlyperfectasitwaspossibletobe。In1818,hefurnishedthelathewithaslideresttwenty-twoincheslong,forthepurposeofcuttingscrews,providedwiththemeansofself-correction;andsomeyearslater,in1827,theSocietyofArtsawardedhimtheirgoldIsismedalforhisimprovedturning-lathe,whichembodiedmanyingeniouscontrivancescalculatedtoincreaseitsprecisionandaccuracyinlargesurface-turning。
ThebeautifularrangementsembodiedinMr。Clement’simprovedlathecanwithdifficultybedescribedinwords;butitsingenuitymaybeinferredfromabriefstatementofthedefectswhichitwasinventedtoremedy,andwhichitsuccessfullyovercame。Whenthemandrillofalathe,havingametalplatefixedtoit,turnsroundwithauniformmotion,andthesliderestwhichcarriesthecutterismovingfromthecircumferenceoftheworktothecentre,itwillbeobviousthatthequantityofmetalpassingovertheedgeofthecutterateachrevolution,andthereforeatequalintervalsoftime,iscontinuallydiminishing,inexactproportiontothespirallinedescribedbythecutteronthefaceofthework。Butinturningmetalplatesitisfoundveryinexpedienttoincreasethespeedoftheworkbeyondacertainquantity;forwhenthishappens,andthetoolpassestheworkattoogreatavelocity,itheats,softens,andisgroundaway,theedgeofthecutterbecomesdull,andthesurfaceoftheplateisindentedandburnished,insteadofbeingturned。Hencelossoftimeonthepartoftheworkman,anddiminishedworkonthepartofthetool,resultswhich,consideringthewagesoftheoneandthecapitalexpendedontheconstructionoftheother,areofnosmallimportance;fortheprimeobjectsofallimprovementoftoolsare,economyoftimeandeconomyofcapital——tominimizelabourandcost,andmaximizeresult。
Thedefecttowhichwehavereferredwasalmosttheonlyremainingimperfectioninthelathe,andMr。Clementovercameitbymakingthemachineself-regulating;sothat,whatevermightbethesituationofthecutter,equalquantitiesofmetalshouldpassoveritinequaltimes,——thespeedatthecentrenotexceedingthatsuitedtotheworkatthecircumference,——whiletheworkmanwasenabledtoconvertthevaryingrateofthemandrillintoauniformonewheneverhechose。
Thustheexpedientsofwheels,riggers,anddrums,ofdifferentdiameters,bywhichithadbeenendeavouredtoalterthespeedofthelathe-mandrill,accordingtothehardnessofthemetalandthediameterofthethingtobeturned,wereeffectuallydisposedof。
These,thoughansweringverywellwherecylindersofequaldiameterhadtobebored,andauniformmotionwasallthatwasrequired,werefoundveryinefficientwhereaPlanesurfacehadtobeturned;anditwasinsuchcasesthatMr。Clement’slathewasfoundsovaluable。Byitsmeanssurfacesofunrivalledcorrectnesswereproduced,andtheslide-lathe,soimproved,becamerecognisedandadoptedasthemostaccurateandextensivelyapplicableofallmachine-tools。
TheyearafterMr。Clementbroughtouthisimprovedturning-lathe,headdedtoithisself-adjustingdoubledrivingcentre-chuck,forwhichtheSocietyofArtsawardedhimtheirsilvermedalin1828。InintroducingthisinventiontothenoticeoftheSociety,Mr。Clementsaid,”AlthoughIhavebeeninthehabitofturningandmakingturning-lathesandothermachineryforupwardsofthirty-fiveyears,andhaveexaminedthebestturning-lathesintheprincipalmanufactoriesthroughoutGreatBritain,Ifindituniversallyregrettedbyallpracticalmenthattheycannotturnanythingperfectlytruebetweenthecentresofthelathe。”Itwasfoundbyexperience,thattherewasadegreeofeccentricity,andconsequentlyofimperfection,inthefigureofanylongcylinderturnedwhilesuspendedbetweenthecentresofthelathe,andmadetorevolvebytheactionofasingledriver。Undersuchcircumstancesthepressureofthetooltendedtoforcetheworkoutoftherightlineandtodistributethestrainbetweenthedriverandtheadjacentcentre,sothatoneendofthecylinderbecameeccentricwithrespecttotheother。ByMr。Clement’sinventionofthetwo-armeddriver,whichwasself-adjusting,thestrainwastakenfromthecentreanddividedbetweenthetwoarms,whichbeingequidistantfromthecentre,effectuallycorrectedalleccentricityinthework。Thisinventionwasfoundofgreatimportanceinensuringthetrueturningoflargemachinery,whichbeforehadbeenfoundamatterofconsiderabledifficulty。