For，inrespecttothelatterbranchofthesupposition，itshouldbeconsideredthatthemosttriflingvariationinthefactsofthetwocasesmightgiverisetothemostimportantmiscalculations，bydivertingthoroughlythetwocoursesofevents；verymuchas，inarithmetic，anerrorwhich，initsownindividuality，maybeinappreciable，produces，atlength，bydintofmultiplicationatallpointsoftheprocess，aresultenormouslyatvariancewithtruth。
　　And，inregardtotheformerbranch，wemustnotfailtoholdinviewthattheveryCalculusofProbabilitiestowhichIhavereferred，forbidsallideaoftheextensionoftheparallel：-forbidsitwithapositivenessstronganddecidedjustinproportionasthisparallelhasalreadybeenlong-drawnandexact。Thisisoneofthoseanomalouspropositionswhich，seeminglyappealingtothoughtaltogetherapartfromthemathematical，isyetonewhichonlythemathematiciancanfullyentertain。Nothing，forexample，ismoredifficultthantoconvincethemerelygeneralreaderthatthefactofsixeshavingbeenthrowntwiceinsuccessionbyaplayeratdice，issufficientcauseforbettingthelargestoddsthatsixeswillnotbethrowninthethirdattempt。Asuggestiontothiseffectisusuallyrejectedbytheintellectatonce。Itdoesnotappearthatthetwothrowswhichhavebeencompleted，andwhichlienowabsolutelyinthePast，canhaveinfluenceuponthethrowwhichexistsonlyintheFuture。Thechanceforthrowingsixesseemstobepreciselyasitwasatanyordinarytime-thatistosay，subjectonlytotheinfluenceofthevariousotherthrowswhichmaybemadebythedice。Andthisisareflectionwhichappearssoexceedinglyobviousthatattemptstocontrovertitarereceivedmorefrequentlywithaderisivesmilethanwithanythinglikerespectfulattention。Theerrorhereinvolved-agrosserrorredolentofmischief-Icannotpretendtoexposewithinthelimitsassignedmeatpresent；andwiththephilosophicalitneedsnoexposure。ItmaybesufficientheretosaythatitformsoneofaninfiniteseriesofmistakeswhichariseinthepathorReasonthroughherpropensityforseekingtruthindetail。
　　{*1}Upontheoriginalpublicationof“MarieRoget。”thefoot-notesnowappendedwereconsideredunnecessary；butthelapseofseveralyearssincethetragedyuponwhichthetaleisbased，rendersitexpedienttogivethem，andalsotosayafewwordsinexplanationofthegeneraldesign。Ayounggirl，MaryCeciliaRogers，wasmurderedinthevicinityofNewYork；and，althoughherdeathoccasionedanintenseandlong-enduringexcitement，themysteryattendingithadremainedunsolvedattheperiodwhenthepresentpaperwaswrittenandpublishedNovember，1842。Herein，underpretenceofrelatingthefateofaParisiangrisette，theauthorhasfollowedinminutedetail，theessential，whilemerelyparallelingtheinessentialfactsoftherealmurderofMaryRogers。Thusallargumentfoundeduponthefictionisapplicabletothetruth：andtheinvestigationofthetruthwastheobject。The“MysteryofMarieRoget“wascomposedatadistancefromthesceneoftheatrocity，andwithnoothermeansofinvestigationthanthenewspapersafforded。Thusmuchescapedthewriterofwhichhecouldhaveavailedhimselfhadhebeenuponthespot，andvisitedthelocalities。Itmaynotbeimpropertorecord，nevertheless，thattheconfessionsoftwopersons，oneofthemtheMadameDelucofthenarrativemade，atdifferentperiods，longsubsequenttothepublication，confirmed，infull，notonlythegeneralconclusion，butabsolutelyallthechiefhypotheticaldetailsbywhichthatconclusionwasattained。
　　TheNewYork“Mercury。”
　　TheNewYork“BrotherJonathan。”editedbyH。HastingsWeld，Esq。
　　NewYork“JournalofCommerce。”
　　Philadelphia“SaturdayEveningPost。”editedbyC。I。Peterson，Esq。
　　Adam{*14}See“MurdersintheRueMorgue。”
　　TheNewYork“CommercialAdvertiser。”editedbyCol。Stone。
　　“Atheorybasedonthequalitiesofanobject，willpreventitsbeingunfoldedaccordingtoitsobjects；andhewhoarrangestopicsinreferencetotheircauses，willceasetovaluethemaccordingtotheirresults。Thusthejurisprudenceofeverynationwillshowthat，whenlawbecomesascienceandasystem，itceasestobejustice。Theerrorsintowhichablinddevotiontoprinciplesofclassificationhasledthecommonlaw，willbeseenbyobservinghowoftenthelegislaturehasbeenobligedtocomeforwardtorestoretheequityitsschemehadlost。”-Landor。
　　[AstoundingNewsbyExpress，_via_Norfolk！-TheAtlanticcrossedinThreeDays！SignalTriumphofMr。MonckMason’sFlyingMachine！-ArrivalatSullivan’sIsland，nearCharlestown，S。C。，ofMr。Mason，Mr。RobertHolland，Mr。Henson，Mr。HarrisonAinsworth，andfourothers，intheSteeringBalloon，“Victoria。”afterapassageofSeventy-fiveHoursfromLandtoLand！FullParticularsoftheVoyage！
　　Thesubjoined_jeud’esprit_withtheprecedingheadinginmagnificentcapitals，wellinterspersedwithnotesofadmiration，wasoriginallypublished，asmatteroffact，inthe“NewYorkSun。”adailynewspaper，andthereinfullysubservedthepurposeofcreatingindigestiblealimentforthe_quidnuncs_duringthefewhoursinterveningbetweenacoupleoftheCharlestonmails。Therushforthe“solepaperwhichhadthenews。”wassomethingbeyondeventheprodigious；and，infact，ifassomeassertthe“Victoria“_did_
　　notabsolutelyaccomplishthevoyagerecorded，itwillbedifficulttoassignareasonwhyshe_should_nothaveaccomplishedit。]
　　THEgreatproblemisatlengthsolved！Theair，aswellastheearthandtheocean，hasbeensubduedbyscience，andwillbecomeacommonandconvenienthighwayformankind。_TheAtlantichasbeenactuallycrossedinaBalloon！_andthistoowithoutdifficulty-
　　withoutanygreatapparentdanger-withthoroughcontrolofthemachine-andintheinconceivablybriefperiodofseventy-fivehoursfromshoretoshore！BytheenergyofanagentatCharleston，S。C。，weareenabledtobethefirsttofurnishthepublicwithadetailedaccountofthismostextraordinaryvoyage，whichwasperformedbetweenSaturday，the6thinstant，at11，A。M。，and2，P。M。，onTuesday，the9thinstant，bySirEverardBringhurst；Mr。Osborne，anephewofLordBentinck’s；Mr。MonckMasonandMr。RobertHolland，thewell-known鎟onauts；Mr。HarrisonAinsworth，authorof“JackSheppard。”&c。；andMr。Henson，theprojectorofthelateunsuccessfulflyingmachine-withtwoseamenfromWoolwich-inall，eightpersons。Theparticularsfurnishedbelowmaybereliedonasauthenticandaccurateineveryrespect，as，withaslightexception，theyarecopied_verbatim_fromthejointdiariesofMr。MonckMasonandMr。HarrisonAinsworth，towhosepolitenessouragentisalsoindebtedformuchverbalinformationrespectingtheballoonitself，itsconstruction，andothermattersofinterest。TheonlyalterationintheMS。received，hasbeenmadeforthepurposeofthrowingthehurriedaccountofouragent，Mr。Forsyth，intoaconnectedandintelligibleform。
　　“THEBALLOON。
　　“Twoverydecidedfailures，oflate-thoseofMr。HensonandSirGeorgeCayley-hadmuchweakenedthepublicinterestinthesubjectofaerialnavigation。Mr。Henson’sschemewhichatfirstwasconsideredveryfeasibleevenbymenofscience，wasfoundedupontheprincipleofaninclinedplane，startedfromaneminencebyanextrinsicforce，appliedandcontinuedbytherevolutionofimpingingvanes，informandnumberresemblingthevanesofawindmill。But，inalltheexperimentsmadewithmodelsattheAdelaideGallery，itwasfoundthattheoperationofthesefansnotonlydidnotpropelthemachine，butactuallyimpededitsflight。Theonlypropellingforceiteverexhibited，wasthemere_impetus_acquiredfromthedescentoftheinclinedplane；andthis_impetus_carriedthemachinefartherwhenthevaneswereatrest，thanwhentheywereinmotion-afactwhichsufficientlydemonstratestheirinutility；
　　andintheabsenceofthepropelling，whichwasalsothe_sustaining_
　　power，thewholefabricwouldnecessarilydescend。ThisconsiderationledSirGeorgeCayleytothinkonlyofadaptingapropellertosomemachinehavingofitselfanindependentpowerofsupport-inaword，toaballoon；theidea，however，beingnovel，ororiginal，withSirGeorge，onlysofarasregardsthemodeofitsapplicationtopractice。HeexhibitedamodelofhisinventionatthePolytechnicInstitution。Thepropellingprinciple，orpower，washere，also，appliedtointerruptedsurfaces，orvanes，putinrevolution。Thesevaneswerefourinnumber，butwerefoundentirelyineffectualinmovingtheballoon，orinaidingitsascendingpower。
　　Thewholeprojectwasthusacompletefailure。
　　“ItwasatthisjuncturethatMr。MonckMasonwhosevoyagefromDovertoWeilburgintheballoon，“Nassau。”occasionedsomuchexcitementin1837，conceivedtheideaofemployingtheprincipleoftheArchimedeanscrewforthepurposeofpropulsionthroughtheair-
　　rightlyattributingthefailureofMr。Henson’sscheme，andofSirGeorgeCayley’s，totheinterruptionofsurfaceintheindependentvanes。HemadethefirstpublicexperimentatWillis’sRooms，butafterwardremovedhismodeltotheAdelaideGallery。
　　“LikeSirGeorgeCayley’sballoon，hisownwasanellipsoid。Itslengthwasthirteenfeetsixinches-height，sixfeeteightinches。
　　Itcontainedaboutthreehundredandtwentycubicfeetofgas，which，ifpurehydrogen，wouldsupporttwenty-onepoundsuponitsfirstinflation，beforethegashastimetodeteriorateorescape。Theweightofthewholemachineandapparatuswasseventeenpounds-
　　leavingaboutfourpoundstospare。Beneaththecentreoftheballoon，wasaframeoflightwood，aboutninefeetlong，andriggedontotheballoonitselfwithanetworkinthecustomarymanner。
　　Fromthisframeworkwassuspendedawickerbasketorcar。
　　“Thescrewconsistsofanaxisofhollowbrasstube，eighteeninchesinlength，throughwhich，uponasemi-spiralinclinedatfifteendegrees，passaseriesofsteelwireradii，twofeetlong，andthusprojectingafootoneitherside。Theseradiiareconnectedattheouterextremitiesbytwobandsofflattenedwire-thewholeinthismannerformingtheframeworkofthescrew，whichiscompletedbyacoveringofoiledsilkcutintogores，andtightenedsoastopresentatolerablyuniformsurface。Ateachendofitsaxisthisscrewissupportedbypillarsofhollowbrasstubedescendingfromthehoop。Inthelowerendsofthesetubesareholesinwhichthepivotsoftheaxisrevolve。Fromtheendoftheaxiswhichisnextthecar，proceedsashaftofsteel，connectingthescrewwiththepinionofapieceofspringmachineryfixedinthecar。Bytheoperationofthisspring，thescrewismadetorevolvewithgreatrapidity，communicatingaprogressivemotiontothewhole。Bymeansoftherudder，themachinewasreadilyturnedinanydirection。Thespringwasofgreatpower，comparedwithitsdimensions，beingcapableofraisingforty-fivepoundsuponabarreloffourinchesdiameter，afterthefirstturn，andgraduallyincreasingasitwaswoundup。Itweighed，altogether，eightpoundssixounces。Therudderwasalightframeofcanecoveredwithsilk，shapedsomewhatlikeabattledoor，andwasaboutthreefeetlong，andatthewidest，onefoot。Itsweightwasabouttwoounces。Itcouldbeturned_flat_，anddirectedupwardsordownwards，aswellastotherightorleft；andthusenabledthe鎟onauttotransfertheresistanceoftheairwhichinaninclinedpositionitmustgenerateinitspassage，toanysideuponwhichhemightdesiretoact；thusdeterminingtheballoonintheoppositedirection。
　　“Thismodelwhich，throughwantoftime，wehavenecessarilydescribedinanimperfectmanner，wasputinactionattheAdelaideGallery，whereitaccomplishedavelocityoffivemilesperhour；
　　although，strangetosay，itexcitedverylittleinterestincomparisonwiththepreviouscomplexmachineofMr。Henson-soresoluteistheworldtodespiseanythingwhichcarrieswithitanairofsimplicity。Toaccomplishthegreatdesideratumof鎟ialnavigation，itwasverygenerallysupposedthatsomeexceedinglycomplicatedapplicationmustbemadeofsomeunusuallyprofoundprincipleindynamics。
　　“Sowellsatisfied，however，wasMr。Masonoftheultimatesuccessofhisinvention，thathedeterminedtoconstructimmediately，ifpossible，aballoonofsufficientcapacitytotestthequestionbyavoyageofsomeextent-theoriginaldesignbeingtocrosstheBritishChannel，asbefore，intheNassauballoon。Tocarryouthisviews，hesolicitedandobtainedthepatronageofSirEverardBringhurstandMr。Osborne，twogentlemenwellknownforscientificacquirement，andespeciallyfortheinteresttheyhaveexhibitedintheprogressof鎟ostation。Theproject，atthedesireofMr。Osborne，waskeptaprofoundsecretfromthepublic-theonlypersonsentrustedwiththedesignbeingthoseactuallyengagedintheconstructionofthemachine，whichwasbuiltunderthesuperintendenceofMr。Mason，Mr。Holland，SirEverardBringhurst，andMr。Osborne，attheseatofthelattergentlemannearPenstruthal，inWales。Mr。Henson，accompaniedbyhisfriendMr。