MostofthosepresenthaveatsometimeintheirlivesheardmentionmadeoftheMETALLICTRACTORS，inventedbyoneDr。Perkins，anAmerican，andformerlyenjoyinggreatreputeforthecureofvariousdiseases。Manyhaveseenorheardofasatiricalpoem，writtenbyoneofourowncountrymenalso，aboutfortyyearssince，andcalled“TerribleTractoration。“TheMetallicTractorsarenowsoutterlyabandonedthatIhaveonlybygoodfortunefallenuponasingleoneofapair，toshowforthesakeofillustration。Formorethanthirtyyearsthisgreatdiscovery，whichwastobanishatleasthalftheevilswhichafflicthumanity，hasbeensleepingundisturbedinthegraveofoblivion。Notavoicehas，forthislongperiod，beenraisedinitsfavor；itsnobleandlearnedpatrons，itspublicinstitutions，itseloquentadvocates，itsbrilliantpromisesareallcoveredwiththedustofsilentneglect；andofthegenerationwhichhassprungupsincetheperiodwhenitflourished，veryfewknowanythingofitshistory，andhardlyeventhetitlewhichinitspalmydaysitboreofPERKINISM。Takingitassettled，then，asnooneappearstoanswerforit，thatPerkinismisentirelydeadandgone，thatbothinpublicandprivate，officiallyandindividually，itsformeradherentsevenallowittobeabsolutelydefunct，Iselectitforanatomicalexamination。Ifthispretendeddiscoverywasmadepublic；ifitwaslongkeptbeforethepublic；ifitwasaddressedtothepeopleofdifferentcountries；ifitwasformallyinvestigatedbyscientificmen，andsystematicallyadoptedbybenevolentpersons，whodideverythingintheirpowertodiffusetheknowledgeandpracticeofit；ifvariouscollateralmotives，suchasinterestandvanity，wereembarkedinitscause；if，notwithstandingallthesethings，itgraduallysickenedanddied，thentheconclusionseemsafairone，thatitdidnotdeservetolive。Contrastingitsfailurewithitshighpretensions，itisfairtocallitanimposition；whetheranexpresslyfraudulentcontrivanceornot，somemightbereadytoquestion。Everythinghistoricallyshowntohavehappenedconcerningthemodeofpromulgation，thewidediffusion，theapparentsuccessofthisdelusion，therespectabilityandenthusiasmofitsadvocates，isofgreatinterestinshowingtowhatextentandbywhatmeansaconsiderablepartofthecommunitymaybeledintothebeliefofthatwhichistobeeventuallyconsidered’asanidlefolly。Ifthereisanyexistingfolly，fraudulentorinnocentinitsorigin，whichappealstocertainargumentsforitssupport；providedthattheverysameargumentscanbeshowntohavebeenusedforPerkinismwithasgoodreason，theywillatoncefalltotheground。Stillmore，ifitshallappearthatthegeneralcourseofanyexistingdelusionbearsastrongresemblancetothatofPerkinism，thattheformerismostfrequentlyadvocatedbythesameclassofpersonswhowereconspicuousinbehalfofthelatter，andtreatedwithcontemptoropposedbythesamekindofpersonswhothustreatedPerkinism；ifthefactsinfavorofbothhaveasimilaraspect；ifthemotivesoftheiroriginatorsandpropagatorsmaybepresumedtohavebeensimilar；thenthereiseveryreasontosupposethattheexistingfollywillfollowinthefootstepsofthepast，andafterdisplayingagivenamountofcunningandcredulityinthosedeceivinganddeceived，willdropfromthepublicviewlikeafruitwhichhasripenedintospontaneousrottenness，andbesucceededbythefreshbloomofsomeotherdelusionrequiredbythesameexcitableportionofthecommunity。
Dr。ElishaPerkinswasbornatNorwich，Connecticut，intheyear1740。Hehadpractisedhisprofessionwithagoodlocalreputationformanyyears，whenhefelluponacourseofexperiments，asitisrelated，whichledtohisgreatdiscovery。Heconceivedtheideathatmetallicsubstancesmighthavetheeffectofremovingdiseases，ifappliedinacertainmanner；anotionprobablysuggestedbythethenrecentexperimentsofGalvani，inwhichmuscularcontractionswerefoundtobeproducedbythecontactoftwometalswiththelivingfibre。Itwasin1796thathisdiscoverywaspromulgatedintheshapeoftheMetallicTractors，twopiecesofmetal，oneapparentlyironandtheotherbrass，aboutthreeincheslong，bluntatoneendandpointedattheother。Theseinstrumentswereappliedforthecureofdifferentcomplaints，suchasrheumatism，localpains，inflammations，andeventumors，bydrawingthemovertheaffectedpartverylightlyforabouttwentyminutes。Dr。Perkinstookoutapatentforhisdiscovery，andtravelledaboutthecountrytodiffusethenewpractice。Hesoonfoundnumerousadvocatesofhisdiscovery，manyofthemofhighstandingandinfluence。Intheyear1798thetractorshadcrossedtheAtlantic，andwerepubliclyemployedintheRoyalHospitalatCopenhagen。Aboutthesametimethesonoftheinventor，Mr。BenjaminDouglassPerkins，carriedthemtoLondon，wheretheysoonattractedattention。TheDanishphysicianspublishedanaccountoftheircases，containingnumerousinstancesofallegedsuccess，inarespectableoctavovolume。Intheyear1804anestablishment，honoredwiththenameofthePerkineanInstitution，wasfoundedinLondon。Thetransactionsofthisinstitutionwerepublishedinpamphlets，thePerkineanSocietyhadpublicdinnersattheCrownandAnchor，andapoetcelebratedtheirmedicaltriumphinstrainslikethese：
“See，pointedmetals，blestwithpowert’appeaseTheruthlessrageofmercilessdisease，O’erthefrailpartasubtlefluidpour，DrenchedwithinvisibleGalvanicshower，Tillthearthriticstaffandcrutchforego，Andleapexultingliketheboundingroe！“
Whileallthesethingsweregoingon，Mr。BenjaminDouglassPerkinswascalmlypocketingmoney，sothataftersomehalfadozenyearsheleftthecountrywithmorethantenthousandpounds，whichhadbeenpaidhimbythebelieversinGreatBritain。Butinspiteofallthissuccess，andthenumberofthoseinterestedandcommittedinitsbehalf，Perkinismsoonbegantodecline，andin1811theTractorsarespokenofbyanintelligentwriterasbeingalmostforgotten。Suchwastheoriginanddurationofthisdoctrineandpractice，intothehistoryofwhichwewillnowlookalittlemorenarrowly。
Letussee，then，bywhoseagencythisdelusionwasestablishedandkeptup；whetheritwasprincipallybythosewhowereaccustomedtomedicalpursuits，orthosewhosehabitsandmodesofreasoningweredifferent；whetheritwaswiththeapprobationofthoselearnedbodiesusuallysupposedtotakeaninterestinscientificdiscoveries，oronlyofindividualswhoseclaimstodistinctionwerefoundedupontheirpositioninsociety，orpoliticalstation，orliteraryeminence；whetherthejudiciousorexcitableclassesenteredmostdeeplyintoit；whether，inshort，thescientificmenofthattimeweredeceived，oronlyintrudedupon，andshouteddownforthemomentbypersonswhohadnoparticularcalltoinvadetheirprecincts。