Dangersofanotherkindmightmorereasonablybeapprehendedfromthisperfectanddistinctorganization，civilandmilitary，oftheStates；towit，thatcertainStatesfromlocalandoccasionaldiscontents，mightattempttosecedefromtheUnion。Thisiscertainlypossible；andwouldbebefriendedbythisregularorganization。Butitisnotprobablethatlocaldiscontentscanspreadtosuchanextent，astobeabletofacethesoundpartsofsoextensiveanUnion；andifevertheyshouldreachthemajority，theywouldthenbecometheregulargovernment，acquiretheascendencyinCongress，andbeabletoredresstheirowngrievancesbylawspeaceablyandconstitutionallypassed。AndeventheStatesinwhichlocaldiscontentsmightengenderacommencementoffermentation，wouldbeparalyzedandself-checkedbythatverydivisionintopartiesintowhichwehavefallen，intowhichallStatesmustfallwhereinmenareatlibertytothink，speak，andactfreely，accordingtothediversitiesoftheirindividualconformations，andwhichare，perhaps，essentialtopreservethepurityofthegovernment，bythecensorshipwhichthesepartieshabituallyexerciseovereachother。
　　Youwillread，Iamsure，withindulgence，theexplanationsofthegroundsonwhichIhaveventuredtoformanopiniondifferingfromyours。Theyprovemyrespectforyourjudgment，anddiffidenceinmyown，whichhaveforbiddenmetoretain，withoutexamination，anopinionquestionedbyyou。Permitmenowtorendermyportionofthegeneraldebtofgratitude，byacknowledgementsinadvanceforthesingularbenefactionwhichisthesubjectofthisletter，totendermywishesforthecontinuanceofalifesousefullyemployed，andtoaddtheassurancesofmyperfectesteemandrespect。
　　THELATINAMERICANREVOLUTION
　　_ToAlexandervonHumboldt_
　　_Monticello，April14，1811_
　　MYDEARBARON，——TheinterruptionofourintercoursewithFranceforsometimepast，haspreventedmywritingtoyou。A
　　conveyancenowoccurs，byMr。BarloworMr。Warden，bothofthemgoinginapubliccapacity。ItisthefirstsafeopportunityofferedofacknowledgingyourfavorofSeptember23d，andthereceiptatdifferenttimesoftheIIIdpartofyourvaluablework，2d，3d，4thand5thlivraisons，andtheIVthpart，2d，3d，and4thlivraisons，withthe_Tableauxdelanature_，andaninterestingmapofNewSpain。Forthesemagnificentandmuchesteemedfavors，acceptmysincerethanks。TheygiveusaknowledgeofthatcountrymoreaccuratethanIbelievewepossessofEurope，theseatofthescienceofathousandyears。Itcomesout，too，atamomentwhenthosecountriesarebeginningtobeinterestingtothewholeworld。Theyarenowbecomingthescenesofpoliticalrevolution，totaketheirstationsasintegralmembersofthegreatfamilyofnations。Allarenowininsurrection。Inseveral，theIndependentsarealreadytriumphant，andtheywillundoubtedlybesoinall。Whatkindofgovernmentwilltheyestablish?Howmuchlibertycantheybearwithoutintoxication?Aretheirchiefssufficientlyenlightenedtoformawell-guardedgovernment，andtheirpeopletowatchtheirchiefs?HavetheymindenoughtoplacetheirdomesticatedIndiansonafootingwiththewhites?Allthesequestionsyoucananswerbetterthananyother。Iimaginetheywillcopyouroutlinesofconfederationandelectivegovernment，abolishdistinctionofranks，bowthenecktotheirpriests，andpersevereinintolerantism。Theirgreatestdifficultywillbeintheconstructionoftheirexecutive。
　　Isuspectthat，regardlessoftheexperimentofFrance，andofthatoftheUnitedStatesin1784，theywillbeginwithadirectory，andwhentheunavoidableschismsinthatkindofexecutiveshalldrivethemtosomethingelse，theirgreatquestionwillcomeonwhethertosubstituteanexecutiveelectiveforyears，forlife，oranhereditaryone。Butunlessinstructioncanbespreadamongthemmorerapidlythanexperiencepromises，despotismmaycomeuponthembeforetheyarequalifiedtosavethegroundtheywillhavegained。CouldNapoleonobtain，atthecloseofthepresentwar，theindependenceofalltheWestIndiaislands，andtheirestablishmentinaseparateconfederacy，ourquarteroftheglobewouldexhibitanenrapturingprospectintofuturity。Youwilllivetoseemuchofthis。Ishallfollow，however，cheerfullymyfellowlaborers，contentedwithhavingborneapartinbeginningthisbeatificreformation。
　　Ifear，fromsomeexpressionsinyourletter，thatyourpersonalinterestshavenotbeendulyprotected，whileyouweredevotingyourtime，talentsandlaborfortheinformationofmankind。
　　Ishouldsincerelyregretitforthehonorofthegoverningpowers，aswellasfromaffectionateattachmenttoyourselfandthesincerestwishesforyourfelicity，fortunesandfame。
　　InsendingyouacopyofmyNotesonVirginia，Idobutobeythedesireyouhaveexpressed。TheymustappearchetifenoughtotheauthorofthegreatworkonSouthAmerica。Butfromthewidowhermitewaswelcome，andyouwilladdtothisindulgencetheacceptanceofmysincereassurancesofconstantfriendshipandrespect。”AYOUNGGARDENER”
　　_ToCharlesWillsonPeale_
　　_PoplarForest，August20，1811_
　　Itislong，mydearSir，sincewehaveexchangedaletter。Ourformercorrespondencehadalwayssomelittlematterofbusinessinterspersed；butthisbeingatanend，Ishallstillbeanxioustohearfromyousometimes，andtoknowthatyouarewellandhappy。I
　　knowindeedthatyoursystemisthatofcontentmentunderanysituation。Ihaveheardthatyouhaveretiredfromthecitytoafarm，andthatyougiveyourwholetimetothat。Doesnotthemuseumsuffer?Andisthefarmasinteresting?Here，asyouknow，weareallfarmers，butnotinapleasingstyle。Wehavesolittlelaborinproportiontoourlandthat，althoughperhapswemakemoreprofitfromthesamelabor，wecannotgivetoourgroundsthatstyleofbeautywhichsatisfiestheeyeoftheamateur。Ourrotationsarecorn，wheat，andclover，orcorn，wheat，cloverandclover，orwheat，corn，wheat，cloverandclover；precedingthecloverbyaplastering。
　　Butsome，insteadofcloversubstitutemererest，andallareslovenlyenough。WeareaddingthecareofMerinosheep。Ihaveoftenthoughtthatifheavenhadgivenmechoiceofmypositionandcalling，itshouldhavebeenonarichspotofearth，wellwatered，andnearagoodmarketfortheproductionsofthegarden。Nooccupationissodelightfultomeasthecultureoftheearth，andnoculturecomparabletothatofthegarden。Suchavarietyofsubjects，someonealwayscomingtoperfection，thefailureofonethingrepairedbythesuccessofanother，andinsteadofoneharvestacontinuedonethroughtheyear。Underatotalwantofdemandexceptforourfamilytable，Iamstilldevotedtothegarden。Butthoughanoldman，Iambutayounggardener。
　　YourapplicationtowhateveryouareengagedinIknowtobeincessant。ButSundaysandrainydaysarealwaysdaysofwritingforthefarmer。Thinkofmesometimeswhenyouhaveyourpeninhand，andgivemeinformationofyourhealthandoccupations；andbealwaysassuredofmygreatesteemandrespect。
　　REPRISE：WEIGHTS，MEASURES，ANDCOINS
　　_ToDr。RobertPatterson_
　　_Monticello，November10，1811_
　　DEARSIR，——YourfavorofSeptember23dcametohandinduetime，andIthankyouforthenauticalalmanacitcoveredfortheyear1813。IlearnwithpleasurethatthePhilosophicalSocietyhasconcludedtotakeintoconsiderationthesubjectofafixedstandardofmeasures，weightsandcoins，andyouaskmyideasonit；insulatedasmysituationis，IamsureIcanoffernothingbutwhatwilloccurtothecommitteeengagedonit，withtheadvantageontheirpartofcorrectionbyaninterchangeofsentimentsandobservationsamongthemselves。Iwill，however，hazardsomegeneralideasbecauseyoudesireit，andifasingleonebeuseful，thelaborwillnotbelost。
　　Thesubjecttobereferredtoasastandard，whetheritbematterormotion，shouldbefixedbynature，invariableandaccessibletoallnations，independentlyofothers，andwithaconveniencenotdisproportionedtoitsutility。Whatsubjectinnaturefulfilsbesttheseconditions?Whatsystemshallweproposeonthis，embracingmeasures，weightsandcoins?andinwhatformshallwepresentittotheworld?Thesearethequestionsbeforethecommittee。
　　Someothersubjectshave，atdifferenttimes，beenproposedasstandards，buttwoonlyhavedividedtheopinionsofmen：first，adirectadmeasurementofalineontheearth’ssurface，orsecond，ameasurederivedfromitsmotiononitsaxis。Tomeasuredirectlysuchaportionoftheearthaswouldfurnishanelementofmeasure，whichmightbefoundagainwithcertaintyinallfuturetimes，wouldbetoofarbeyondthecompetenceofourmeanstobetakenintoconsideration。Iamfree，atthesametime，tosaythatifthesewerewithinourpowerinthemostampledegree，thiselementwouldnotmeetmypreference。Theadmeasurementwouldofcoursebeofaportionofsomegreatcircleoftheearth。Ifoftheequator，thecountriesoverwhichthatpasses，theircharacterandremoteness，rendertheundertakingarduous，andwemaysayimpracticableformostnations。Ifofsomemeridian，thevaryingmeasuresofitsdegreesfromtheequatortothepole，requireameantobesought，ofwhichsomealiquotpartmayfurnishwhatisdesired。Forthispurposethe45thdegreehasbeenrecurredto，andsuchalengthoflineonbothsidesofitterminatingateachendintheocean，asmayfurnishasatisfactorylawforadeductionoftheunmeasuredpartofthequadrant。TheportionresortedtobytheFrenchphilosophers，andthereisnootherontheglobeundercircumstancesequallysatisfactory，isthemeridianpassingthroughtheircountryandaportionofSpain，fromDunkirktoBarcelona。Theobjectionstosuchanadmeasurementasanelementofmeasure，arethelabor，thetime，thenumberofhighly-qualifiedagents，andthegreatexpenserequired。Allthis，too，istoberepeatedwheneveranyaccidentshallhavedestroyedthestandardderivedfromit，orimpaireditsdimensions。Thisportionofthatparticularmeridianisaccessibleofrighttonoonenationonearth。France，indeed，availingherselfofamomentofpeculiarrelationbetweenSpainandherself，hasexecutedsuchanadmeasurement。Buthowwoulditbeatthismoment，astoeitherFranceorSpain?andhowisitatalltimesastoothernations，inpointeitherofrightorofpractice?Mustthesegothroughthesameoperation，ortaketheirmeasuresfromthestandardpreparedbyFrance?Neithercasebearsthatcharacterofindependencewhichtheproblemrequires，andwhichneithertheequalitynorconvenienceofnationscandispensewith。Howwoulditnowbe，wereEnglandthedepositofastandardfortheworld?Atwarwithalltheworld，thestandardwouldbeinaccessibletoallothernations。Againstthis，too，aretheinaccuraciesofadmeasurementsoverhillsandvalleys，mountainsandwaters，inaccuraciesoftenunobservedbytheagenthimself，andalwaysunknowntotheworld。
　　Thevariousresultsofthedifferentmeasuresheretoforeattempted，sufficientlyprovetheinadequacyofhumanmeanstomakesuchanadmeasurementwiththeexactnessrequisite。
　　Letusnowseeunderwhatcircumstancesthependulumoffersitselfasanelementofmeasure。Themotionoftheearthonitsaxisfromnoontonoonofameansolarday，hasbeendividedfromtimeimmemorial，andbyverygeneralconsent，into86，400portionsoftimecalledseconds。Thelengthofapendulumvibratinginoneoftheseportions，isdeterminedbythelawsofnature，isinvariableunderthesameparallel，andaccessibleindependentlytoallmen。Likeadegreeofthemeridian，indeed，itvariesinitslengthfromtheequatortothepole，andlikeit，too，requirestobereducedtoamean。Inseekingameaninthefirstcase，the45thdegreeoccurswithunrivalledpreferences。Itisthemid-wayofthecelestialarkfromtheequatortothepole。Itisameanbetweenthetwoextremedegreesoftheterrestrialark，orbetweenanytwoequi-distantfromit，anditisalsoameanvalueofallitsdegrees。Inlikemanner，whenseekingameanforthependulum，thesame45thdegreeoffersitselfonthesamegrounds，itsincrementsbeinggovernedbythesamelawswhichdeterminethoseofthedifferentdegreesofthemeridian。
　　InapendulumloadedwithaBob，somedifficultyoccursinfindingthecentreofoscillation；andconsequentlythedistancebetweenthatandthepointofsuspension。Tolessenthis，ithasbeenproposedtosubstituteforthependulum，acylindricalrodofsmalldiameter，inwhichthedisplacementofthecentreofoscillationwouldbelessened。IthasalsobeenproposedtoprolongthesuspendingwireofthependulumbelowtheBob，untiltheircentresofoscillationshallcoincide。Butthesepropositionsnotappearingtohavereceivedgeneralapprobation，werecurtothependulum，suspendedandchargedashasbeenusual。Andtheratherasthethelawswhichdeterminethecentreofoscillationleavenoroomforerrorinfindingit，otherthanthatminimuminpracticetowhichalloperationsaresubjectintheirexecution。Theothersourcesofinaccuracyinthelengthofthependulumneednotbementioned，becauseeasilyguardedagainst。Butthegreatanddecisivesuperiorityofthependulum，asastandardofmeasure，isinitsaccessibilitytoallmen，atalltimesandinallplaces。Toobtainthesecondpendulumfor45degreesitisnotnecessarytogoactuallytothatlatitude。Havingascertaineditslengthinourownparallel，boththeoryandobservationgiveusalawforascertainingthedifferencebetweenthatandthependulumofanyother。Tomakeanewmeasuretherefore，orverifyanoldone，nothingisnecessaryinanyplacebutawell-regulatedtime-piece，oragoodmeridian，andsuchaknowledgeofthesubjectasiscommoninallcivilizednations。
　　Thoseindeedwhohavepreferredtheotherelement，dojusticetothecertainty，aswellassuperiorfacilitiesofthependulum，byproposingtorecurtooneofthelengthoftheirstandard，andtoascertainitsnumberofvibrationsinaday。Thesebeingonceknown，ifanyaccidentimpairtheirstandarditistoberecovedbymeansofapendulumwhichshallmaketherequisitenumberofvibrationsinaday。AndamongtheseveralcommissionsestablishedbytheAcademyofSciencesfortheexecutionoftheseveralbranchesoftheirworkonmeasuresandweights，thatrespectingthependulumwasassignedtoMessrs。Borda，Coulomb&Cassini，theresultofwhoselabors，however，Ihavenotlearned。
　　Letourunitofmeasuresthenbeapendulumofsuchlengthasinthelatitudeof45degrees，intheleveloftheocean，andinagiventemperature，shallperformitsvibrations，insmallandequalarcs，inonesecondofmeantime。
　　Whatratioshallweadoptforthepartsandmultiplesofthisunit?Thedecimalwithoutadoubt。Ourarithmaticbeingfoundedinadecimalnumeration，thesamenumerationinasystemofmeasures，weightsandcoins，talliesatoncewiththat。Onthisquestion，I
　　believe，therehasbeennodifferenceofopinion。
　　Inmeasuresoflength，then，thependulumisourunit。Itisalittlemorethanouryardandlessthantheell。Itstenthordime，willnotbequite。4inches。Itshundredth，orcent，notquite。4ofaninch；itsthousandth，ormill，notquite。04ofaninch，andsoon。Thetravellerwillcounthisroadbyalongermeasure。1，000
　　units，orakiliad，willnotbequitetwo-thirdsofourpresentmile，andmorenearlyathousandpacesthanthat。
　　Formeasuresofsurface，thesquareunit，equaltoabouttensquarefeet，orone-ninthmorethanasquareyard，willbegenerallyconvenient。Butforthoseoflandsalargermeasurewillbewanted。
　　Akiliadwouldbenotquitearood，orquarterofanacre；amyriadnotquite21/2acres。
　　Formeasuresofcapacity，wetanddry，ThecubicUnit=。1wouldbeabout。35cubicfeet，。28bushelsdry，or7/8ofatonliquid。
　　Dime=。1wouldbeabout3。5cubicfeet，2。8bushels，orabout7/8ofabarrelliquid。
　　Cent=。01about50cubicinches，or7/8ofaquart。
　　Mill=。001=。5ofacubicinch，or2/3ofagill。
　　Toincorporateintothesamesystemourweightsandcoins，wemustrecurtosomenaturalsubstance，tobefoundeverywhere，andofacompositionsufficientlyuniform。Waterhasbeenconsideredasthemosteligiblesubstance，andrain-watermorenearlyuniformthananyotherkindfoundinnature。Thatcircumstancerendersitpreferabletodistilledwater，anditsvariationsinweightmaybecalledinsensible。
　　Thecubicunitofthis=。1wouldweighabout2，165lbs。oratonbetweenthelongandshort。
　　TheDime=。1alittlemorethan2。kentals。
　　Cent=。01alittlemorethan20lb。
　　Mill=。001alittlemorethan2lb。
　　Decimmil=。0001about31/2oz。avoirdupoise。
　　Centimmil=。00001alittlemorethan6dwt。
　　Millionth=。000001about15grains。
　　Decimmillionth=。0000001about11/2grains。
　　Centimmillionth=。00000001about。14ofagrain。
　　Billionth=。000000001about。014ofagrain。
　　Withrespecttoourcoins，thepuresilverinadollarbeingfixedbylawat3471/4grains，andalldebtsandcontractsbeingbottomedonthatvalue，wecanonlystatethepuresilverinthedollar，whichwouldbeverynearly23millionths。