“Howisthisknown？”askedDupin。
　　“Itisclearlyinferred。”repliedthePrefect，“fromthenatureofthedocument，andfromthenon-appearanceofcertainresultswhichwouldatoncearisefromitspassingoutoftherobber’spossession；
　　thatistosay，fromhisemployingitashemustdesignintheendtoemployit。”
　　“Bealittlemoreexplicit。”Isaid。
　　“Well，Imayventuresofarastosaythatthepapergivesitsholderacertainpowerinacertainquarterwheresuchpowerisimmenselyvaluable。”ThePrefectwasfondofthecantofdiplomacy。
　　“StillIdonotquiteunderstand。”saidDupin。
　　“No？Well；thedisclosureofthedocumenttoathirdperson，whoshallbenameless，wouldbringinquestionthehonorofapersonageofmostexaltedstation；andthisfactgivestheholderofthedocumentanascendancyovertheillustriouspersonagewhosehonorandpeacearesojeopardized。”
　　“Butthisascendancy。”Iinterposed，“woulddependupontherobber’sknowledgeoftheloser’sknowledgeoftherobber。Whowoulddare-“
　　“Thethief。”saidG。，“istheMinisterD，whodaresallthings，thoseunbecomingaswellasthosebecomingaman。Themethodofthetheftwasnotlessingeniousthanbold。Thedocumentinquestion-aletter，tobefrank-hadbeenreceivedbythepersonagerobbedwhilealoneintheroyalboudoir。Duringitsperusalshewassuddenlyinterruptedbytheentranceoftheotherexaltedpersonagefromwhomespeciallyitwasherwishtoconcealit。Afterahurriedandvainendeavortothrustitinadrawer，shewasforcedtoplaceit，openasitwas，uponatable。Theaddress，however，wasuppermost，and，thecontentsthusunexposed，theletterescapednotice。AtthisjunctureenterstheMinisterD。Hislynxeyeimmediatelyperceivesthepaper，recognisesthehandwritingoftheaddress，observestheconfusionofthepersonageaddressed，andfathomshersecret。Aftersomebusinesstransactions，hurriedthroughinhisordinarymanner，heproducesalettersomewhatsimilartotheoneinquestion，opensit，pretendstoreadit，andthenplacesitinclosejuxtapositiontotheother。Againheconverses，forsomefifteenminutes，uponthepublicaffairs。Atlength，intakingleave，hetakesalsofromthetablethelettertowhichhehadnoclaim。Itsrightfulownersaw，but，ofcourse，darednotcallattentiontotheact，inthepresenceofthethirdpersonagewhostoodatherelbow。Theministerdecamped；
　　leavinghisownletter-oneofnoimportance-uponthetable。”
　　“Here，then。”saidDupintome，“youhavepreciselywhatyoudemandtomaketheascendancycomplete-therobber’sknowledgeoftheloser’sknowledgeoftherobber。”
　　“Yes。”repliedthePrefect；“andthepowerthusattainedhas，forsomemonthspast，beenwielded，forpoliticalpurposes，toaverydangerousextent。Thepersonagerobbedismorethoroughlyconvinced，everyday，ofthenecessityofreclaimingherletter。Butthis，ofcourse，cannotbedoneopenly。Infine，driventodespair，shehascommittedthemattertome。”
　　“Thanwhom。”saidDupin，amidaperfectwhirlwindofsmoke，“nomoresagaciousagentcould，Isuppose，bedesired，orevenimagined。”
　　“Youflatterme。”repliedthePrefect；“butitispossiblethatsomesuchopinionmayhavebeenentertained。”
　　“Itisclear。”saidI，“asyouobserve，thattheletterisstillinpossessionoftheminister；sinceitisthispossession，andnotanyemploymentoftheletter，whichbestowsthepower。Withtheemploymentthepowerdeparts。”
　　“True。”saidG。；“anduponthisconvictionIproceeded。Myfirstcarewastomakethoroughsearchoftheminister’shotel；andheremychiefembarrassmentlayinthenecessityofsearchingwithouthisknowledge。Beyondallthings，Ihavebeenwarnedofthedangerwhichwouldresultfromgivinghimreasontosuspectourdesign。”
　　“But。”saidI，“youarequiteaufaitintheseinvestigations。TheParisianpolicehavedonethisthingoftenbefore。”
　　“Oyes；andforthisreasonIdidnotdespair。Thehabitsoftheministergaveme，too，agreatadvantage。Heisfrequentlyabsentfromhomeallnight。Hisservantsarebynomeansnumerous。Theysleepatadistancefromtheirmaster’sapartment，and，beingchieflyNeapolitans，arereadilymadedrunk。Ihavekeys，asyouknow，withwhichIcanopenanychamberorcabinetinParis。Forthreemonthsanighthasnotpassed，duringthegreaterpartofwhichIhavenotbeenengaged，personally，inransackingtheDHotel。Myhonorisinterested，and，tomentionagreatsecret，therewardisenormous。
　　SoIdidnotabandonthesearchuntilIhadbecomefullysatisfiedthatthethiefisamoreastutemanthanmyself。IfancythatIhaveinvestigatedeverynookandcornerofthepremisesinwhichitispossiblethatthepapercanbeconcealed。”
　　“Butisitnotpossible。”Isuggested，“thatalthoughthelettermaybeinpossessionoftheminister，asitunquestionablyis，hemayhaveconcealeditelsewherethanuponhisownpremises？”
　　“Thisisbarelypossible。”saidDupin。“Thepresentpeculiarconditionofaffairsatcourt，andespeciallyofthoseintriguesinwhichDisknowntobeinvolved，wouldrendertheinstantavailabilityofthedocument-itssusceptibilityofbeingproducedatamoment’snotice-apointofnearlyequalimportancewithitspossession。”
　　“Itssusceptibilityofbeingproduced？”saidI。
　　“Thatistosay，ofbeingdestroyed。”saidDupin。
　　“True。”Iobserved；“thepaperisclearlythenuponthepremises。Asforitsbeinguponthepersonoftheminister，wemayconsiderthatasoutofthequestion。”
　　“Entirely。”saidthePrefect。“Hehasbeentwicewaylaid，asifbyfootpads，andhispersonrigorouslysearchedundermyowninspection。”
　　“Youmighthavesparedyourselfthistrouble。”saidDupin。“D，I
　　presume，isnotaltogetherafool，and，ifnot，musthaveanticipatedthesewaylayings，asamatterofcourse。”
　　“Notaltogetherafool。”saidG。，“butthenhe’sapoet，whichItaketobeonlyoneremovefromafool。”
　　“True。”saidDupin，afteralongandthoughtfulwhifffromhismeerschaum，“althoughIhavebeenguiltyofcertaindoggrelmyself。”
　　“Supposeyoudetail。”saidI，“theparticularsofyoursearch。”
　　“Whythefactis，wetookourtime，andwesearchedeverywhere。I
　　havehadlongexperienceintheseaffairs。Itooktheentirebuilding，roombyroom；devotingthenightsofawholeweektoeach。
　　Weexamined，first，thefurnitureofeachapartment。Weopenedeverypossibledrawer；andIpresumeyouknowthat，toaproperlytrainedpoliceagent，suchathingasasecretdrawerisimpossible。Anymanisadoltwhopermitsa’secret’drawertoescapehiminasearchofthiskind。Thethingissoplain。Thereisacertainamountofbulk-
　　ofspace-tobeaccountedforineverycabinet。Thenwehaveaccuraterules。Thefiftiethpartofalinecouldnotescapeus。
　　Afterthecabinetswetookthechairs。Thecushionsweprobedwiththefinelongneedlesyouhaveseenmeemploy。Fromthetablesweremovedthetops。”
　　“Whyso？”
　　“Sometimesthetopofatable，orothersimilarlyarrangedpieceoffurniture，isremovedbythepersonwishingtoconcealanarticle；
　　thenthelegisexcavated，thearticledepositedwithinthecavity，andthetopreplaced。Thebottomsandtopsofbedpostsareemployedinthesameway。”
　　“Butcouldnotthecavitybedetectedbysounding？”Iasked。
　　“Bynomeans，if，whenthearticleisdeposited，asufficientwaddingofcottonbeplacedaroundit。Besides，inourcase，wewereobligedtoproceedwithoutnoise。”
　　“Butyoucouldnothaveremoved-youcouldnothavetakentopiecesallarticlesoffurnitureinwhichitwouldhavebeenpossibletomakeadepositinthemanneryoumention。Alettermaybecompressedintoathinspiralroll，notdifferingmuchinshapeorbulkfromalargeknitting-needle，andinthisformitmightbeinsertedintotherungofachair，forexample。Youdidnottaketopiecesallthechairs？”
　　“Certainlynot；butwedidbetter-weexaminedtherungsofeverychairinthehotel，and，indeedthejointingsofeverydescriptionoffurniture，bytheaidofamostpowerfulmicroscope。Hadtherebeenanytracesofrecentdisturbanceweshouldnothavefailedtodetectitinstantly。Asinglegrainofgimlet-dust，forexample，wouldhavebeenasobviousasanapple。Anydisorderintheglueing-anyunusualgapinginthejoints-wouldhavesufficedtoinsuredetection。”
　　“Ipresumeyoulookedtothemirrors，betweentheboardsandtheplates，andyouprobedthebedsandthebed-clothes，aswellasthecurtainsandcarpets。”
　　“Thatofcourse；andwhenwehadabsolutelycompletedeveryparticleofthefurnitureinthisway，thenweexaminedthehouseitself。Wedivideditsentiresurfaceintocompartments，whichwenumbered，sothatnonemightbemissed；thenwescrutinizedeachindividualsquareinchthroughoutthepremises，includingthetwohousesimmediatelyadjoining，withthemicroscope，asbefore。”
　　“Thetwohousesadjoining！”Iexclaimed；“youmusthavehadagreatdealoftrouble。”
　　“Wehad；buttherewardofferedisprodigious！”
　　“Youincludethegroundsaboutthehouses？”
　　“Allthegroundsarepavedwithbrick。Theygaveuscomparativelylittletrouble。Weexaminedthemossbetweenthebricks，andfounditundisturbed。”
　　“YoulookedamongD’spapers，ofcourse，andintothebooksofthelibrary？”
　　“Certainly；weopenedeverypackageandparcel；wenotonlyopenedeverybook，butweturnedovereveryleafineachvolume，notcontentingourselveswithamereshake，accordingtothefashionofsomeofourpoliceofficers。Wealsomeasuredthethicknessofeverybook-cover，withthemostaccurateadmeasurement，andappliedtoeachthemostjealousscrutinyofthemicroscope。Hadanyofthebindingsbeenrecentlymeddledwith，itwouldhavebeenutterlyimpossiblethatthefactshouldhaveescapedobservation。Somefiveorsixvolumes，justfromthehandsofthebinder，wecarefullyprobed，longitudinally，withtheneedles。”
　　“Youexploredthefloorsbeneaththecarpets？”
　　“Beyonddoubt。Weremovedeverycarpet，andexaminedtheboardswiththemicroscope。”
　　“Andthepaperonthewalls？”
　　“Yes。”
　　“Youlookedintothecellars？”
　　“Wedid。”
　　“Then。”Isaid，“youhavebeenmakingamiscalculation，andtheletterisnotuponthepremises，asyousuppose。”
　　“Ifearyouarerightthere。”saidthePrefect。“Andnow，Dupin，whatwouldyouadvisemetodo？”
　　“Tomakeathoroughre-searchofthepremises。”
　　“Thatisabsolutelyneedless。”repliedG。“IamnotmoresurethatIbreathethanIamthattheletterisnotattheHotel。”
　　“Ihavenobetteradvicetogiveyou。”saidDupin。“Youhave，ofcourse，anaccuratedescriptionoftheletter？”
　　“Ohyes！”-AndherethePrefect，producingamemorandum-bookproceededtoreadaloudaminuteaccountoftheinternal，andespeciallyoftheexternalappearanceofthemissingdocument。Soonafterfinishingtheperusalofthisdescription，hetookhisdeparture，moreentirelydepressedinspiritsthanIhadeverknownthegoodgentlemanbefore。Inaboutamonthafterwardshepaidusanothervisit，andfoundusoccupiedverynearlyasbefore。Hetookapipeandachairandenteredintosomeordinaryconversation。AtlengthIsaid，-
　　“Well，butG，whatofthepurloinedletter？IpresumeyouhaveatlastmadeupyourmindthatthereisnosuchthingasoverreachingtheMinister？”
　　“Confoundhim，sayI-yes；Imadethere-examination，however，asDupinsuggested-butitwasalllaborlost，asIknewitwouldbe。”
　　“Howmuchwastherewardoffered，didyousay？”askedDupin。
　　“Why，averygreatdeal-averyliberalreward-Idon’tliketosayhowmuch，precisely；butonethingIwillsay，thatIwouldn’tmindgivingmyindividualcheckforfiftythousandfrancstoanyonewhocouldobtainmethatletter。Thefactis，itisbecomingofmoreandmoreimportanceeveryday；andtherewardhasbeenlatelydoubled。Ifitweretrebled，however，IcoulddonomorethanIhavedone。”
　　“Why，yes。”saidDupin，drawlingly，betweenthewhiffsofhismeerschaum，“Ireally-think，G，youhavenotexertedyourself-
　　totheutmostinthismatter。Youmight-doalittlemore，Ithink，eh？”
　　“How？-inwhatway？’
　　“Why-puff，puff-youmight-puff，puff-employcounselinthematter，eh？-puff，puff，puff。DoyourememberthestorytheytellofAbernethy？”
　　“No；hangAbernethy！”