Explainthedevice。””Iwilldrawit。””Youcan?””AsIseeit。””Asyouseeit！””Yes。It’sabrilliantidea；Icouldneverhaveconceivedit。””Youbelieve-””Iknow。””Sithere。Let’sseewhatyouknow。”
　　Sweetwatersatdownatthetabletheotherpointedout，anddrawingforwardapieceofpaper，tookupapencilwithaneasyair。
　　Brothersonapproachedandstoodathisshoulder。Hehadtakenuphispistolagain，whyhehardlyknew，andasSweetwaterbeganhismarks，hisfingerstightenedonitsbutttilltheyturnedwhiteinthemurkylamplight。”Yousee，”cameineasytonesfromthestoopingdraughtsman，”I
　　haveanimaginationwhichonlyneedsaslightfillipfromamindlikeyourstosenditinthedesireddirection。Ishallnotdrawanexactreproductionofyouridea，butIthinkyouwillseethatIunderstanditverywell。How’sthatforastart?”
　　Brothersonlookedandhastilydrewback。Hedidnotwanttheothertonotehissurprise。”Butthatisaportionyouneversaw，”heloudlydeclared。”No，butIsawthis，”returnedSweetwater，workingbusilyonsomecurves；”andthesegavemethefillipImentioned。Therestcameeasily。”
　　Brotherson，indreadofhisownanger，threwhispistoltotheotherendoftheshed：”Youknave！Youthief！”hefuriouslycried。”Howso?”askedSweetwatersmilingly，risingandlookinghimcalmlyintheface。”Athiefisonewhoappropriatesanotherman’sgoods，or，letussay，anotherman’sideas。Ihaveappropriatednothingyet。I’veonlyshownyouhoweasilyIcoulddoso。Mr。Brotherson，takemeinasyourassistant。Iwillbefaithfultoyou，Iswearit。
　　Iwanttoseethatmachinegoup。””Forhowmanypeoplehaveyoudrawnthoselines?”thunderedtheinexorablevoice。”Fornobody；notformyselfeven。Thisisthefirsttimetheyhavelefttheirhiding-placeinmybrain。””Canyousweartothat?””Icanandwill，ifyourequireit。Butyououghttobelievemyword，sir。Iamsquareasadieinallmattersnotconnected-well，notconnectedwithmyprofession，”hesmiledinaburstofthatwhimsicalhumour，whichnoteventheseriousnessofthemomentcouldquitesuppress。”AndwhatsuretyhaveIthatyoudonotconsiderthisverymatterofmineascomingwithintheboundsyouspeakof?””None。Butyoumusttrustmethatfar。”
　　Brothersonsurveyedhimwithanironywhichconveyedaverydifferentmessagetothedetectivethananyhehadintended。Thenquickly：”Tohowmanyhaveyouspoken，dilatinguponthisdevice，andpublishingabroadmysecret?””Ihavespokentonoone，noteventoMr。Gryce。Thatshowsmyhonestyasnothingelsecan。””Youhavekeptmysecretintact?””Entirelyso，sir。””Sothatnoone，hereorelsewhere，sharesourknowledgeofthenewpointsinthismechanism?””Isayso，sir。””ThenifIshouldkillyou，”cameinferociousaccents，”now-here-””Youwouldbetheonlyonetoownthatknowledge。Butyouwon’tkillme。””Why?””NeedIgointoreasons?”Why?Isay。””Becauseyourconscienceisalreadytooheavilyladentobeartheburdenofanotherunprovokedcrime”
　　Brotherson，startingback，glaredwithopenferocityuponthemanwhodaredtofacehimwithsuchanaccusation。”God！whydidn’tIshootyouonentrance！”hecried。”Yourcourageiscertainlycolossal。”
　　Afinesmile，withouteventhehintofhumournow，touchedthedaringdetective’slip。Brotherson’sangerseemedtogrowunderit，andheloudlyrepeated：”It’smorethancolossal；it’sabnormaland-”Amoment’spause，thenwithironicpauses-”andquiteunnecessarysaveasamatterofdisplay，unlessyouthinkyouneedittosustainyouthroughtheordealyouarecourting。Youwishtohelpmefinishandprepareforflight?”
　　Isincerelydo。””Youconsideryourselfcompetent?””Ido。”
　　Brotherson’seyesfellandhewalkedoncetotheextremityoftheovalflooringandback。”Well，wewillgrantthat。Butthat’snotallthatisnecessary。
　　Myrequirementsdemandacompanioninmyfirstflight。WillyougoupinthecarwithmeonSaturdaynight?”
　　AquickaffirmativewasonSweetwater’slipsbuttheglimpsewhichhegotofthespeaker’sfacegloweringuponhimfromtheshadowsintowhichBrothersonhadwithdrawn，stoppeditsutterance，andthesilencegrewheavy。Thoughitmaynothavelastedlongbytheclock，theinstantofbreathlesscontemplationofeachother’sfeaturesacrosstheinterveningspacewasofincalculablemomenttoSweetwater，and，possibly，toBrotherson。Asdrowningmenaresaidtoliveovertheirwholehistorybetweentheirfirstplungeandtheirfinalrisetolightandair，sothroughthemindofthedetectiverushedthememoriesofhispastandthefastfadinggloriesofhisfuture；andrebellingatthesubtleperilhesawinthatsardoniceye，hevociferatedanimpulsive：”No！I’llnot-”andpaused，caughtbyanewandirresistiblesensation。
　　Abreathofwind-thefirsthe，hadfeltthatnight-hadsweptinthroughsomecreviceinthecurvingwall，flappingthecanvasenvelopingthegreatcar。Itactedlikeapealtobattle。Afterall，amanmusttakesomerisksinhislife，andhisheartwasinthistrialofaredoubtablemechanisminwhichhehadfullfaith。
　　Hecouldnotsaynototheprospectofbeingthefirsttoshareatriumphwhichwouldsendhisnametotheendsoftheearth；and，changingthetrendofhissentence，herepeatedwithacalmnesswhichhadtheforceofagreatdecisionIwillnotfailyouinanything。Ifsherises-herehistremblinghandfellonthecurtainshuttingoffhisviewoftheship，”sheshalltakemewithher，sothatwhenshedescendsImaybethefirsttocongratulatetheproudinventorofsuchamarvel。”
　　Sobeit！”shotfromtheother’slips，hiseyeslosingtheirthreateninglook，andhiswholecountenancesuddenlyaglowwiththeenthusiasmofawakenedgenius。
　　Comingfromtheshadows，helaidhishandonthecordregulatingtheriseandfalloftheconcealingcurtain。”Heresheis！”hecriedanddrewthecord。
　　Thecanvasshook，gathereditselfintogreatfoldsanddisappearedintheshadowsfromwhichhehadjuststepped。
　　Theair-carstoodrevealed-astartling，becausewhollyunique，vision。
　　LongdidSweetwatersurveyit，thenturningwithbeamingfaceuponthewatchfulinventor，heutteredaloudHurrah。
　　Nextmoment，witheverythingforgottenbetweenthemsavethegloriesofthisinvention，bothdroppedsimultaneouslytothefloorandbeganthatminuteexaminationofthemechanismnecessarytotheirmutualwork。