Towardthesouth，theplainwasveryflat，withoutoneelevation，withoutoneprojection。Towardthenorth，onthecontrary，tillwhereitwasboundedbythe"SeaofStorms，"itresembledaliquidsurfaceagitatedbyastorm，ofwhichthehillsandhollowsformedasuccessionofwavessuddenlycongealed。
Overthewholeofthis，andinalldirections，laytheluminouslines，allconvergingtothesummitofCopernicus。
Thetravelersdiscussedtheoriginofthesestrangerays；buttheycouldnotdeterminetheirnatureanymorethanterrestrialobservers。
"Butwhy，"saidNicholl，"shouldnottheseraysbesimplyspursofmountainswhichreflectmorevividlythelightofthesun？"
"No，"repliedBarbicane；"ifitwasso，undercertainconditionsofthemoon，theseridgeswouldcastshadows，andtheydonotcastany。"
Andindeed，theseraysonlyappearedwhentheorbofdaywasinoppositiontothemoon，anddisappearedassoonasitsraysbecameoblique。
"Buthowhavetheyendeavoredtoexplaintheselinesoflight？"
askedMichel；"forIcannotbelievethatsavantswouldeverbestrandedforwantofanexplanation。"
"Yes，"repliedBarbicane；"Herschelhasputforwardanopinion，buthedidnotventuretoaffirmit。"
"Nevermind。Whatwastheopinion？"
"Hethoughtthattheseraysmightbestreamsofcooledlavawhichshonewhenthesunbeatstraightuponthem。Itmaybeso；
butnothingcanbelesscertain。Besides，ifwepassnearertoTycho，weshallbeinabetterpositiontofindoutthecauseofthisradiation。"
"Doyouknow，myfriends，whatthatplain，seenfromtheheightweareat，resembles？"saidMichel。
"No，"repliedNicholl。
"Verywell；withallthosepiecesoflavalengthenedlikerockets，itresemblesanimmensegameofspelikansthrownpellmell。
Therewantsbutthehooktopullthemoutonebyone。"
"Dobeserious，"saidBarbicane。
"Well，letusbeserious，"repliedMichelquietly；"andinsteadofspelikans，letusputbones。Thisplain，wouldthenbenothingbutanimmensecemetery，onwhichwouldreposethemortalremainsofthousandsofextinctgenerations。Doyoupreferthathigh-flowncomparison？"
"Oneisasgoodastheother，"retortedBarbicane。
"Myword，youaredifficulttoplease，"answeredMichel。
"Myworthyfriend，"continuedthematter-of-factBarbicane，"itmattersbutlittlewhatit_resembles_，whenwedonotknowwhatit_is_。"
"Wellanswered，"exclaimedMichel。"Thatwillteachmetoreasonwithsavants。"
Buttheprojectilecontinuedtoadvancewithalmostuniformspeedaroundthelunardisc。Thetravelers，wemayeasilyimagine，didnotdreamoftakingamoment'srest。Everyminutechangedthelandscapewhichfledfrombeneaththeirgaze。
Abouthalfpastoneo'clockinthemorning，theycaughtaglimpseofthetopsofanothermountain。Barbicane，consultinghismap，recognizedEratosthenes。
Itwasaringedmountainninethousandfeethigh，andoneofthosecirclessonumerousonthissatellite。Withregardtothis，BarbicanerelatedKepler'ssingularopinionontheformationofcircles。Accordingtothatcelebratedmathematician，thesecrater-likecavitieshadbeendugbythehandofman。
"Forwhatpurpose？"askedNicholl。
"Foraverynaturalone，"repliedBarbicane。"TheSelenitesmighthaveundertakentheseimmenseworksanddugtheseenormousholesforarefugeandshieldfromthesolarrayswhichbeatuponthemduringfifteenconsecutivedays。"
"TheSelenitesarenotfools，"saidMichel。
"Asingularidea，"repliedNicholl；"butitisprobablethatKeplerdidnotknowthetruedimensionsofthesecircles，forthediggingofthemwouldhavebeentheworkofgiantsquiteimpossiblefortheSelenites。"
"Why？ifweightonthemoon'ssurfaceissixtimeslessthanontheearth？"saidMichel。
"ButiftheSelenitesaresixtimessmaller？"retortedNicholl。
"Andifthereare_no_Selenites？"addedBarbicane。
Thisputanendtothediscussion。
SoonEratosthenesdisappearedunderthehorizonwithouttheprojectilebeingsufficientlyneartoallowcloseobservation。
ThismountainseparatedtheApenninesfromtheCarpathians。Inthelunarorographytheyhavediscernedsomechainsofmountains，whicharechieflydistributedoverthenorthernhemisphere。Some，however，occupycertainportionsofthesouthernhemispherealso。
Abouttwoo'clockinthemorningBarbicanefoundthattheywereabovethetwentiethlunarparallel。Thedistanceoftheprojectilefromthemoonwasnotmorethansixhundredmiles。
Barbicane，nowperceivingthattheprojectilewassteadilyapproachingthelunardisc，didnotdespair；ifnotofreachingher，atleastofdiscoveringthesecretsofherconfiguration。
CHAPTERXIII
LUNARLANDSCAPES
Athalf-pasttwointhemorning，theprojectilewasoverthethirteenthlunarparallelandattheeffectivedistanceoffivehundredmiles，reducedbytheglassestofive。Itstillseemedimpossible，however，thatitcouldevertouchanypartofthedisc。
Itsmotivespeed，comparativelysomoderate，wasinexplicabletoPresidentBarbicane。Atthatdistancefromthemoonitmusthavebeenconsiderable，toenableittobearupagainstherattraction。
Herewasaphenomenonthecauseofwhichescapedthemagain。
Besides，timefailedthemtoinvestigatethecause。Alllunarreliefwasdefilingundertheeyesofthetravelers，andtheywouldnotloseasingledetail。
Undertheglassesthediscappearedatthedistanceoffivemiles。Whatwouldanaeronaut，bornetothisdistancefromtheearth，distinguishonitssurface？Wecannotsay，sincethegreatestascensionhasnotbeenmorethan25，000feet。
This，however，isanexactdescriptionofwhatBarbicaneandhiscompanionssawatthisheight。Largepatchesofdifferentcolorsappearedonthedisc。Selenographersarenotagreeduponthenatureofthesecolors。Thereareseveral，andrathervividlymarked。JuliusSchmidtpretendsthat，iftheterrestrialoceansweredriedup，aSeleniteobservercouldnotdistinguishontheglobeagreaterdiversityofshadesbetweentheoceansandthecontinentalplainsthanthoseonthemoonpresenttoaterrestrialobserver。Accordingtohim，thecolorcommontothevastplainsknownbythenameof"seas"isadarkgraymixedwithgreenandbrown。Someofthelargecraterspresentthesameappearance。BarbicaneknewthisopinionoftheGermanselenographer，anopinionsharedbyBoeerandMoedler。
Observationhasprovedthatrightwasontheirside，andnotonthatofsomeastronomerswhoadmittheexistenceofonlygrayonthemoon'ssurface。Insomepartsgreenwasverydistinct，suchassprings，accordingtoJuliusSchmidt，fromtheseasof"SerenityandHumors。"Barbicanealsonoticedlargecraters，withoutanyinteriorcones，whichshedabluishtintsimilartothereflectionofasheetofsteelfreshlypolished。Thesecolorsbelongedreallytothelunardisc，anddidnotresult，assomeastronomerssay，eitherfromtheimperfectionintheobjectiveoftheglassesorfromtheinterpositionoftheterrestrialatmosphere。
NotadoubtexistedinBarbicane'smindwithregardtoit，asheobserveditthroughspace，andsocouldnotcommitanyopticalerror。
Heconsideredtheestablishmentofthisfactasanacquisitiontoscience。Now，weretheseshadesofgreen，belongingtotropicalvegetation，keptupbyalowdenseatmosphere？Hecouldnotyetsay。
Fartheron，henoticedareddishtint，quitedefined。Thesameshadehadbeforebeenobservedatthebottomofanisolatedenclosure，knownbythenameofLichtenburg'scircle，whichissituatedneartheHercynianmountains，onthebordersofthemoon；buttheycouldnottellthenatureofit。
Theywerenotmorefortunatewithregardtoanotherpeculiarityofthedisc，fortheycouldnotdecideuponthecauseofit。
MichelArdanwaswatchingnearthepresident，whenhenoticedlongwhitelines，vividlylightedupbythedirectraysofthesun。
Itwasasuccessionofluminousfurrows，verydifferentfromtheradiationofCopernicusnotlongbefore；theyranparallelwitheachother。
Michel，withhisusualreadiness，hastenedtoexclaim:
"Lookthere！cultivatedfields！"
"Cultivatedfields！"repliedNicholl，shrugginghisshoulders。
"Plowed，atallevents，"retortedMichelArdan；"butwhatlaborersthoseSelenitesmustbe，andwhatgiantoxentheymustharnesstotheirplowtocutsuchfurrows！"
"Theyarenotfurrows，"saidBarbicane；"theyare_rifts_。"
"Rifts？stuff！"repliedMichelmildly；"butwhatdoyoumeanby`rifts'inthescientificworld？"
Barbicaneimmediatelyenlightenedhiscompanionastowhatheknewaboutlunarrifts。Heknewthattheywereakindoffurrowfoundoneverypartofthediscwhichwasnotmountainous；thatthesefurrows，generallyisolated，measuredfrom400to500
leaguesinlength；thattheirbreadthvariedfrom1，000to1，500
yards，andthattheirborderswerestrictlyparallel；butheknewnothingmoreeitheroftheirformationortheirnature。
Barbicane，throughhisglasses，observedtheseriftswithgreatattention。Henoticedthattheirborderswereformedofsteepdeclivities；theywerelongparallelramparts，andwithsomesmallamountofimaginationhemighthaveadmittedtheexistenceoflonglinesoffortifications，raisedbySeleniteengineers。
Ofthesedifferentriftssomewereperfectlystraight，asifcutbyaline；otherswereslightlycurved，thoughstillkeepingtheirbordersparallel；somecrossedeachother，somecutthroughcraters；heretheywoundthroughordinarycavities，suchasPosidoniusorPetavius；theretheywoundthroughtheseas，suchasthe"SeaofSerenity。"
Thesenaturalaccidentsnaturallyexcitedtheimaginationsoftheseterrestrialastronomers。Thefirstobservationshadnotdiscoveredtheserifts。NeitherHevelius，Cassin，LaHire，norHerschelseemedtohaveknownthem。ItwasSchroeterwhoin1789firstdrewattentiontothem。Othersfollowedwhostudiedthem，asPastorff，Gruithuysen，Boeer，andMoedler。Atthistimetheirnumberamountstoseventy；but，iftheyhavebeencounted，theirnaturehasnotyetbeendetermined；theyarecertainly_not_fortifications，anymorethantheyaretheancientbedsofdried-uprivers；for，ononeside，thewaters，soslightonthemoon'ssurface，couldneverhavewornsuchdrainsforthemselves；and，ontheother，theyoftencrosscratersofgreatelevation。
Wemust，however，allowthatMichelArdanhad"anidea，"andthat，withoutknowingit，hecoincidedinthatrespectwithJuliusSchmidt。
"Why，"saidhe，"shouldnottheseunaccountableappearancesbesimplyphenomenaofvegetation？"
"Whatdoyoumean？"askedBarbicanequickly。
"Donotexciteyourself，myworthypresident，"repliedMichel；
"mightitnotbepossiblethatthedarklinesformingthatbastionwererowsoftreesregularlyplaced？"
"Yousticktoyourvegetation，then？"saidBarbicane。
"Ilike，"retortedMichelArdan，"toexplainwhatyousavantscannotexplain；atleastmyhypotheseshastheadvantageofindicatingwhytheseriftsdisappear，orseemtodisappear，atcertainseasons。"
"Andforwhatreason？"
"Forthereasonthatthetreesbecomeinvisiblewhentheylosetheirleaves，andvisibleagainwhentheyregainthem。"
"Yourexplanationisingenious，mydearcompanion，"repliedBarbicane，"butinadmissible。"
"Why？"
"Because，sotospeak，therearenoseasonsonthemoon'ssurface，andthat，consequently，thephenomenaofvegetationofwhichyouspeakcannotoccur。"
Indeed，theslightobliquityofthelunaraxiskeepsthesunatanalmostequalheightineverylatitude。Abovetheequatorialregionstheradiantorbalmostinvariablyoccupiesthezenith，anddoesnotpassthelimitsofthehorizoninthepolarregions；thus，accordingtoeachregion，therereignsaperpetualwinter，spring，summer，orautumn，asintheplanetJupiter，whoseaxisisbutlittleinclineduponitsorbit。
Whatorigindotheyattributetotheserifts？Thatisaquestiondifficulttosolve。Theyarecertainlyanteriortotheformationofcratersandcircles，forseveralhaveintroducedthemselvesbybreakingthroughtheircircularramparts。Thusitmaybethat，contemporarywiththelatergeologicalepochs，theyareduetotheexpansionofnaturalforces。
Buttheprojectilehadnowattainedthefortiethdegreeoflunarlatitude，atadistancenotexceeding40miles。Throughtheglassesobjectsappearedtobeonlyfourmilesdistant。
Atthispoint，undertheirfeet，roseMountHelicon，1，520feethigh，androundabouttheleftrosemoderateelevations，enclosingasmallportionofthe"SeaofRains，"underthenameoftheGulfofIris。Theterrestrialatmospherewouldhavetobeonehundredandseventytimesmoretransparentthanitis，toallowastronomerstomakeperfectobservationsonthemoon'ssurface；butinthevoidinwhichtheprojectilefloatednofluidinterposeditselfbetweentheeyeoftheobserverandtheobjectobserved。Andmore，Barbicanefoundhimselfcarriedtoagreaterdistancethanthemostpowerfultelescopeshadeverdonebefore，eitherthatofLordRosseorthatoftheRockyMountains。Hewas，therefore，underextremelyfavorableconditionsforsolvingthatgreatquestionofthehabitabilityofthemoon；butthesolutionstillescapedhim；hecoulddistinguishnothingbutdesertbeds，immenseplains，andtowardthenorth，aridmountains。Notaworkbetrayedthehandofman；
notaruinmarkedhiscourse；notagroupofanimalswastobeseenindicatinglife，eveninaninferiordegree。Innopartwastherelife，innopartwasthereanappearanceofvegetation。
Ofthethreekingdomswhichsharetheterrestrialglobebetweenthem，onealonewasrepresentedonthelunarandthatthemineral。
"Ah，indeed！"saidMichelArdan，alittleoutofcountenance；
"thenyouseenoone？"
"No，"answeredNicholl；"uptothistime，notaman，notananimal，notatree！Afterall，whethertheatmospherehastakenrefugeatthebottomofcavities，inthemidstofthecircles，orevenontheoppositefaceofthemoon，wecannotdecide。"
"Besides，"addedBarbicane，"eventothemostpiercingeyeamancannotbedistinguishedfartherthanthreeandahalfmilesoff；
sothat，ifthereareanySelenites，theycanseeourprojectile，butwecannotseethem。"
Towardfourinthemorning，attheheightofthefiftiethparallel，thedistancewasreducedto300miles。Totheleftranalineofmountainscapriciouslyshaped，lyinginthefulllight。Totheright，onthecontrary，layablackhollowresemblingavastwell，unfathomableandgloomy，drilledintothelunarsoil。
Thisholewasthe"BlackLake"；itwasPluto，adeepcirclewhichcanbeconvenientlystudiedfromtheearth，betweenthelastquarterandthenewmoon，whentheshadowsfallfromwesttoeast。
Thisblackcolorisrarelymetwithonthesurfaceofthesatellite。AsyetithasonlybeenrecognizedinthedepthsofthecircleofEndymion，totheeastofthe"ColdSea，"inthenorthernhemisphere，andatthebottomofGrimaldi'scircle，ontheequator，towardtheeasternborderoftheorb。
Plutoisanannularmountain，situatedin51@northlatitude，and9@eastlongitude。Itscircuitisforty-sevenmileslongandthirty-twobroad。
Barbicaneregrettedthattheywerenotpassingdirectlyabovethisvastopening。Therewasanabysstofathom，perhapssomemysteriousphenomenontosurprise；buttheprojectile'scoursecouldnotbealtered。Theymustrigidlysubmit。Theycouldnotguideaballoon，stilllessaprojectile，whenonceenclosedwithinitswalls。Towardfiveinthemorningthenorthernlimitsofthe"SeaofRains"wasatlengthpassed。ThemountsofCondamineandFontenelleremained——oneontheright，theotherontheleft。Thatpartofthediscbeginningwith60@wasbecomingquitemountainous。Theglassesbroughtthemtowithintwomiles，lessthanthatseparatingthesummitofMontBlancfromthelevelofthesea。Thewholeregionwasbristlingwithspikesandcircles。Towardthe60@Philolausstoodpredominantataheightof5，550feetwithitsellipticalcrater，andseenfromthisdistance，thediscshowedaveryfantasticalappearance。
Landscapeswerepresentedtotheeyeunderverydifferentconditionsfromthoseontheearth，andalsoveryinferiortothem。
Themoonhavingnoatmosphere，theconsequencesarisingfromtheabsenceofthisgaseousenvelopehavealreadybeenshown。
Notwilightonhersurface；nightfollowingdayanddayfollowingnightwiththesuddennessofalampwhichisextinguishedorlightedamidprofounddarkness——notransitionfromcoldtoheat，thetemperaturefallinginaninstantfromboilingpointtothecoldofspace。
Anotherconsequenceofthiswantofairisthatabsolutedarknessreignswherethesun'sraysdonotpenetrate。
Thatwhichonearthiscalleddiffusionoflight，thatluminousmatterwhichtheairholdsinsuspension，whichcreatesthetwilightandthedaybreak，whichproducesthe_umbrae_and_penumbrae_，andallthemagicof_chiaro-oscuro_，doesnotexistonthemoon。Hencetheharshnessofcontrasts，whichonlyadmitoftwocolors，blackandwhite。IfaSeleniteweretoshadehiseyesfromthesun'srays，theskywouldseemabsolutelyblack，andthestarswouldshinetohimasonthedarkestnight。JudgeoftheimpressionproducedonBarbicaneandhisthreefriendsbythisstrangescene！Theireyeswereconfused。Theycouldnolongergrasptherespectivedistancesofthedifferentplains。Alunarlandscapewithoutthesofteningofthephenomenaof_chiaro-oscuro_couldnotberenderedbyanearthlylandscapepainter；itwouldbespotsofinkonawhitepage——nothingmore。
Thisaspectwasnotalteredevenwhentheprojectile，attheheightof80@，wasonlyseparatedfromthemoonbyadistanceoffiftymiles；norevenwhen，atfiveinthemorning，itpassedatlessthantwenty-fivemilesfromthemountainofGioja，adistancereducedbytheglassestoaquarterofamile。
Itseemedasifthemoonmightbetouchedbythehand！
Itseemedimpossiblethat，beforelong，theprojectilewouldnotstrikeher，ifonlyatthenorthpole，thebrilliantarchofwhichwassodistinctlyvisibleontheblacksky。
MichelArdanwantedtoopenoneofthescuttlesandthrowhimselfontothemoon'ssurface！Averyuselessattempt；foriftheprojectilecouldnotattainanypointwhateverofthesatellite，Michel，carriedalongbyitsmotion，couldnotattainiteither。
Atthatmoment，atsixo'clock，thelunarpoleappeared。Thedisconlypresentedtothetravelers'gazeonehalfbrilliantlylitup，whiletheotherdisappearedinthedarkness。Suddenlytheprojectilepassedthelineofdemarcationbetweenintenselightandabsolutedarkness，andwasplungedinprofoundnight！
CHAPTERXIV
THENIGHTOFTHREEHUNDREDANDFIFTY-FOURHOURSANDAHALF
Atthemomentwhenthisphenomenontookplacesorapidly，theprojectilewasskirtingthemoon'snorthpoleatlessthantwenty-fivemilesdistance。Somesecondshadsufficedtoplungeitintotheabsolutedarknessofspace。Thetransitionwassosudden，withoutshade，withoutgradationoflight，withoutattenuationoftheluminouswaves，thattheorbseemedtohavebeenextinguishedbyapowerfulblow。
"Melted，disappeared！"MichelArdanexclaimed，aghast。
Indeed，therewasneitherreflectionnorshadow。Nothingmorewastobeseenofthatdisc，formerlysodazzling。Thedarknesswascomplete。andrenderedevenmoresobytheraysfromthestars。
Itwas"thatblackness"inwhichthelunarnightsareinsteeped，whichlastthreehundredandfifty-fourhoursandahalfateachpointofthedisc，alongnightresultingfromtheequalityofthetranslatoryandrotarymovementsofthemoon。Theprojectile，immergedintheconicalshadowofthesatellite，experiencedtheactionofthesolarraysnomorethananyofitsinvisiblepoints。
Intheinterior，theobscuritywascomplete。Theycouldnotseeeachother。Hencethenecessityofdispellingthedarkness。
HoweverdesirousBarbicanemightbetohusbandthegas，thereserveofwhichwassmall，hewasobligedtoaskfromitafictitiouslight，anexpensivebrilliancywhichthesunthenrefused。
"Deviltaketheradiantorb！"exclaimedMichelArdan，"whichforcesustoexpendgas，insteadofgivingushisraysgratuitously。"
"Donotletusaccusethesun，"saidNicholl，"itisnothisfault，butthatofthemoon，whichhascomeandplacedherselflikeascreenbetweenusandit。"
"Itisthesun！"continuedMichel。
"Itisthemoon！"retortedNicholl。
Anidledispute，whichBarbicaneputanendtobysaying:
"Myfriends，itisneitherthefaultofthesunnorofthemoon；
itisthefaultofthe_projectile_，which，insteadofrigidlyfollowingitscourse，hasawkwardlymissedit。Tobemorejust，itisthefaultofthatunfortunatemeteorwhichhassodeplorablyalteredourfirstdirection。"
"Well，"repliedMichelArdan，"asthematterissettled，letushavebreakfast。Afterawholenightofwatchingitisfairtobuildourselvesupalittle。"
Thisproposalmeetingwithnocontradiction，Michelpreparedtherepastinafewminutes。Buttheyateforeating'ssake，theydrankwithouttoasts，withouthurrahs。Theboldtravelersbeingborneawayintogloomyspace，withouttheiraccustomed_cortege_ofrays，feltavagueuneasinessintheirhearts。
The"strange"shadowsodeartoVictorHugo'spenboundthemonallsides。Buttheytalkedovertheinterminablenightofthreehundredandfifty-fourhoursandahalf，nearlyfifteendays，whichthelawofphysicshasimposedontheinhabitantsofthemoon。
Barbicanegavehisfriendssomeexplanationofthecausesandtheconsequencesofthiscuriousphenomenon。
"Curiousindeed，"saidthey；"for，ifeachhemisphereofthemoonisdeprivedofsolarlightforfifteendays，thatabovewhichwenowfloatdoesnotevenenjoyduringitslongnightanyviewoftheearthsobeautifullylitup。Inawordshehasnomoonapplyingthisdesignationtoourglobebutononesideofherdisc。Nowifthiswerethecasewiththeearth——if，forexample，Europeneversawthemoon，andshewasonlyvisibleattheantipodes，imaginetoyourselftheastonishmentofaEuropeanonarrivinginAustralia。"
"Theywouldmakethevoyagefornothingbuttoseethemoon！"
repliedMichel。
"Verywell！"continuedBarbicane，"thatastonishmentisreservedfortheSeleniteswhoinhabitthefaceofthemoonoppositetotheearth，afacewhichiseverinvisibletoourcountrymenoftheterrestrialglobe。"
"Andwhichweshouldhaveseen，"addedNicholl，"ifwehadarrivedherewhenthemoonwasnew，thatistosayfifteendayslater。"
"Iwilladd，tomakeamends，"continuedBarbicane，"thattheinhabitantsofthevisiblefacearesingularlyfavoredbynature，tothedetrimentoftheirbrethrenontheinvisibleface。
Thelatter，asyousee，havedarknightsof354hours，withoutonesingleraytobreakthedarkness。Theother，onthecontrary，whenthesunwhichhasgivenitslightforfifteendayssinksbelowthehorizon，seeasplendidorbriseontheoppositehorizon。
Itistheearth，whichisthirteentimesgreaterthanthediminutivemoonthatweknow——theearthwhichdevelopesitselfatadiameteroftwodegrees，andwhichshedsalightthirteentimesgreaterthanthatqualifiedbyatmosphericstrata——theearthwhichonlydisappearsatthemomentwhenthesunreappearsinitsturn！"
"Nicelyworded！"saidMichel，"slightlyacademicalperhaps。"
"Itfollows，then，"continuedBarbicane，withoutknittinghisbrows，"thatthevisiblefaceofthediscmustbeveryagreeabletoinhabit，sinceitalwayslooksoneitherthesunwhenthemoonisfull，orontheearthwhenthemoonisnew。"
"But，"saidNicholl，"thatadvantagemustbewellcompensatedbytheinsupportableheatwhichthelightbringswithit。"
"Theinconvenience，inthatrespect，isthesameforthetwofaces，fortheearth'slightisevidentlydeprivedofheat。
Buttheinvisiblefaceisstillmoresearchedbytheheatthanthevisibleface。Isaythatfor_you_，Nicholl，becauseMichelwillprobablynotunderstand。"
"Thankyou，"saidMichel。
"Indeed，"continuedBarbicane，"whentheinvisiblefacereceivesatthesametimelightandheatfromthesun，itisbecausethemoonisnew；thatistosay，sheissituatedbetweenthesunandtheearth。Itfollows，then，consideringthepositionwhichsheoccupiesinoppositionwhenfull，thatsheisnearertothesunbytwiceherdistancefromtheearth；andthatdistancemaybeestimatedatthetwo-hundredthpartofthatwhichseparatesthesunfromtheearth，orinroundnumbers400，000miles。Sothatinvisiblefaceissomuchnearertothesunwhenshereceivesitsrays。"
"Quiteright，"repliedNicholl。
"Onthecontrary，"continuedBarbicane。
"Onemoment，"saidMichel，interruptinghisgravecompanion。
"Whatdoyouwant？"
"Iasktobeallowedtocontinuetheexplanation。"
"Andwhy？"
"ToprovethatIunderstand。"
"Getalongwithyou，"saidBarbicane，smiling。
"Onthecontrary，"saidMichel，imitatingthetoneandgesturesofthepresident，"onthecontrary，whenthevisiblefaceofthemoonislitbythesun，itisbecausethemoonisfull，thatistosay，oppositethesunwithregardtotheearth。Thedistanceseparatingitfromtheradiantorbisthenincreasedinroundnumbersto400，000miles，andtheheatwhichshereceivesmustbealittleless。"
"Verywellsaid！"exclaimedBarbicane。"Doyouknow，Michel，that，foranamateur，youareintelligent。"
"Yes，"repliedMichelcoolly，"weareallsoontheBoulevarddesItaliens。"
Barbicanegravelygraspedthehandofhisamiablecompanion，andcontinuedtoenumeratetheadvantagesreservedfortheinhabitantsofthevisibleface。
Amongothers，hementionedeclipsesofthesun，whichonlytakeplaceonthissideofthelunardisc；since，inorderthattheymaytakeplace，itisnecessaryforthemoontobe_inopposition_。Theseeclipses，causedbytheinterpositionoftheearthbetweenthemoonandthesun，canlast_twohours_；duringwhichtime，byreasonoftheraysrefractedbyitsatmosphere，theterrestrialglobecanappearasnothingbutablackpointuponthesun。
"So，"saidNicholl，"thereisahemisphere，thatinvisiblehemispherewhichisveryillsupplied，veryilltreated，bynature。"
"Nevermind，"repliedMichel；"ifweeverbecomeSelenites，wewillinhabitthevisibleface。Ilikethelight。"
"Unless，byanychance，"answeredNicholl，"theatmosphereshouldbecondensedontheotherside，ascertainastronomerspretend。"
"Thatwouldbeaconsideration，"saidMichel。
Breakfastover，theobserversreturnedtotheirpost。Theytriedtoseethroughthedarkenedscuttlesbyextinguishingalllightintheprojectile；butnotaluminoussparkmadeitswaythroughthedarkness。
OneinexplicablefactpreoccupiedBarbicane。Why，havingpassedwithinsuchashortdistanceofthemoon——abouttwenty-fivemilesonly——whytheprojectilehadnotfallen？Ifitsspeedhadbeenenormous，hecouldhaveunderstoodthatthefallwouldnothavetakenplace；but，witharelativelymoderatespeed，thatresistancetothemoon'sattractioncouldnotbeexplained。
Wastheprojectileundersomeforeigninfluence？Didsomekindofbodyretainitintheether？Itwasquiteevidentthatitcouldneverreachanypointofthemoon。Whitherwasitgoing？
Wasitgoingfartherfrom，ornearing，thedisc？Wasitbeingborneinthatprofounddarknessthroughtheinfinityofspace？
Howcouldtheylearn，howcalculate，inthemidstofthisnight？
AllthesequestionsmadeBarbicaneuneasy，buthecouldnotsolvethem。
Certainly，theinvisibleorbwas_there_，perhapsonlysomefewmilesoff；butneitherhenorhiscompanionscouldseeit。
Iftherewasanynoiseonitssurface，theycouldnothearit。
Air，thatmediumofsound，waswantingtotransmitthegroaningsofthatmoonwhichtheArabiclegendscall"amanalreadyhalfgranite，andstillbreathing。"
Onemustallowthatthatwasenoughtoaggravatethemostpatientobservers。Itwasjustthatunknownhemispherewhichwasstealingfromtheirsight。Thatfacewhichfifteendayssooner，orfifteendayslater，hadbeen，orwouldbe，splendidlyilluminatedbythesolarrays，wasthenbeinglostinutterdarkness。
Infifteendayswherewouldtheprojectilebe？Whocouldsay？
Wherewouldthechancesofconflictingattractionshavedrawnitto？Thedisappointmentofthetravelersinthemidstofthisutterdarknessmaybeimagined。Allobservationofthelunardiscwasimpossible。Theconstellationsaloneclaimedalltheirattention；andwemustallowthattheastronomersFaye，Charconac，andSecchi，neverfoundthemselvesincircumstancessofavorablefortheirobservation。
Indeed，nothingcouldequalthesplendorofthisstarryworld，bathedinlimpidether。Itsdiamondssetintheheavenlyvaultsparkledmagnificently。TheeyetookinthefirmamentfromtheSouthernCrosstotheNorthStar，thosetwoconstellationswhichin12，000years，byreasonofthesuccessionofequinoxes，willresigntheirpartofthepolarstars，theonetoCanopusinthesouthernhemisphere，theothertoWegainthenorthern。
ImaginationlosesitselfinthissublimeInfinity，amidwhichtheprojectilewasgravitating，likeanewstarcreatedbythehandofman。Fromanaturalcause，theseconstellationsshonewithasoftluster；theydidnottwinkle，fortherewasnoatmospherewhich，bytheinterventionofitslayersunequallydenseandofdifferentdegreesofhumidity，producesthisscintillation。Thesestarsweresofteyes，lookingoutintothedarknight，amidthesilenceofabsolutespace。
Longdidthetravelersstandmute，watchingtheconstellatedfirmament，uponwhichthemoon，likeavastscreen，madeanenormousblackhole。Butatlengthapainfulsensationdrewthemfromtheirwatchings。Thiswasanintensecold，whichsooncoveredtheinsideoftheglassofthescuttleswithathickcoatingofice。Thesunwasnolongerwarmingtheprojectilewithitsdirectrays，andthusitwaslosingtheheatstoredupinitswallsbydegrees。Thisheatwasrapidlyevaporatingintospacebyradiation，andaconsiderablylowertemperaturewastheresult。Thehumidityoftheinteriorwaschangedintoiceuponcontactwiththeglass，preventingallobservation。
Nichollconsultedthethermometer，andsawthatithadfallentoseventeendegreesCentigradebelowzero。[3]Sothat，inspiteofthemanyreasonsforeconomizing，Barbicane，afterhavingbeggedlightfromthegas，wasalsoobligedtobegforheat。
Theprojectile'slowtemperaturewasnolongerendurable。
Itstenantswouldhavebeenfrozentodeath。
[3]1@Fahrenheit。
"Well！"observedMichel，"wecannotreasonablycomplainofthemonotonyofourjourney！Whatvarietywehavehad，atleastintemperature。Nowweareblindedwithlightandsaturatedwithheat，liketheIndiansofthePampas！nowplungedintoprofounddarkness，amidthecold，liketheEsquimauxofthenorthpole。
No，indeed！wehavenorighttocomplain；naturedoeswondersinourhonor。"
"But，"askedNicholl，"whatisthetemperatureoutside？"
"Exactlythatoftheplanetaryspace，"repliedBarbicane。
"Then，"continuedMichelArdan，"wouldnotthisbethetimetomaketheexperimentwhichwedarednotattemptwhenweweredrownedinthesun'srays？
"Itisnowornever，"repliedBarbicane，"forweareinagoodpositiontoverifythetemperatureofspace，andseeifFourierorPouillet'scalculationsareexact。"
"Inanycaseitiscold，"saidMichel。"See！thesteamoftheinterioriscondensingontheglassesofthescuttles。Ifthefallcontinues，thevaporofourbreathwillfallinsnowaroundus。"
"Letusprepareathermometer，"saidBarbicane。
Wemayimaginethatanordinarythermometerwouldaffordnoresultunderthecircumstancesinwhichthisinstrumentwastobeexposed。Themercurywouldhavebeenfrozeninitsball，asbelow42@Fahrenheitbelowzeroitisnolongerliquid。
ButBarbicanehadfurnishedhimselfwithaspiritthermometeronWafferdin'ssystem，whichgivestheminimaofexcessivelylowtemperatures。
Beforebeginningtheexperiment，thisinstrumentwascomparedwithanordinaryone，andthenBarbicanepreparedtouseit。
"Howshallwesetaboutit？"askedNicholl。
"Nothingiseasier，"repliedMichelArdan，whowasneverataloss。
"Weopenthescuttlerapidly；throwouttheinstrument；itfollowstheprojectilewithexemplarydocility；andaquarterofanhourafter，drawitin。"
"Withthehand？"askedBarbicane。
"Withthehand，"repliedMichel。
"Well，then，myfriend，donotexposeyourself，"answeredBarbicane，"forthehandthatyoudrawinagainwillbenothingbutastumpfrozenanddeformedbythefrightfulcold。"
"Really！"
"Youwillfeelasifyouhadhadaterribleburn，likethatofironatawhiteheat；forwhethertheheatleavesourbodiesbrisklyorentersbriskly，itisexactlythesamething。
Besides，Iamnotatallcertainthattheobjectswehavethrownoutarestillfollowingus。"
"Whynot？"askedNicholl。
"Because，ifwearepassingthroughanatmosphereoftheslightestdensity，theseobjectswillberetarded。Again，thedarknesspreventsourseeingiftheystillfloataroundus。
Butinordernottoexposeourselvestothelossofourthermometer，wewillfastenit，andwecanthenmoreeasilypullitbackagain。"
Barbicane'sadvicewasfollowed。Throughthescuttlerapidlyopened，Nichollthrewouttheinstrument，whichwasheldbyashortcord，sothatitmightbemoreeasilydrawnup。Thescuttlehadnotbeenopenedmorethanasecond，butthatsecondhadsufficedtoletinamostintensecold。
"Thedevil！"exclaimedMichelArdan，"itiscoldenoughtofreezeawhitebear。"
Barbicanewaiteduntilhalfanhourhadelapsed，whichwasmorethantimeenoughtoallowtheinstrumenttofalltothelevelofthesurroundingtemperature。Thenitwasrapidlypulledin。
Barbicanecalculatedthequantityofspiritsofwineoverflowedintothelittlevialsolderedtothelowerpartoftheinstrument，andsaid:
"AhundredandfortydegreesCentigrade[4]belowzero！"
[4]218degreesFahrenheitbelowzero。
M。PouilletwasrightandFourierwrong。Thatwastheundoubtedtemperatureofthestarryspace。Suchis，perhaps，thatofthelunarcontinents，whentheorbofnighthaslostbyradiationalltheheatwhichfifteendaysofsunhavepouredintoher。
CHAPTERXV
HYPERBOLAORPARABOLA
Wemay，perhaps，beastonishedtofindBarbicaneandhiscompanionssolittleoccupiedwiththefuturereservedforthemintheirmetalprisonwhichwasbearingthemthroughtheinfinityofspace。Insteadofaskingwheretheyweregoing，theypassedtheirtimemakingexperiments，asiftheyhadbeenquietlyinstalledintheirownstudy。
Wemightanswerthatmensostrong-mindedwereabovesuchanxieties——thattheydidnottroublethemselvesaboutsuchtrifles——andthattheyhadsomethingelsetodothantooccupytheirmindswiththefuture。
Thetruthwasthattheywerenotmastersoftheirprojectile；
theycouldneithercheckitscourse，noralteritsdirection。
Asailorcanchangetheheadofhisshipashepleases；anaeronautcangiveaverticalmotiontohisballoon。They，onthecontrary，hadnopowerovertheirvehicle。Everymaneuverwasforbidden。Hencetheinclinationtoletthingsalone，orasthesailorssay，"letherrun。"
Wheredidtheyfindthemselvesatthismoment，ateighto'clockinthemorningofthedaycalledupontheearththe6thofDecember？
Verycertainlyintheneighborhoodofthemoon，andevennearenoughforhertolooktothemlikeanenormousblackscreenuponthefirmament。Astothedistancewhichseparatedthem，itwasimpossibletoestimateit。Theprojectile，heldbysomeunaccountableforce，hadbeenwithinfourmilesofgrazingthesatellite'snorthpole。
Butsinceenteringtheconeofshadowtheselasttwohours，hadthedistanceincreasedordiminished？Everypointofmarkwaswantingbywhichtoestimateboththedirectionandthespeedoftheprojectile。
Perhapsitwasrapidlyleavingthedisc，sothatitwouldsoonquitthepureshadow。Perhaps，again，ontheotherhand，itmightbenearingitsomuchthatinashorttimeitmightstrikesomehighpointontheinvisiblehemisphere，whichwoulddoubtlesslyhaveendedthejourneymuchtothedetrimentofthetravelers。
Adiscussionaroseonthissubject，andMichelArdan，alwaysreadywithanexplanation，gaveitashisopinionthattheprojectile，heldbythelunarattraction，wouldendbyfallingonthesurfaceoftheterrestrialglobelikeanaerolite。
"Firstofall，myfriend，"answeredBarbicane，"everyaerolitedoesnotfalltotheearth；itisonlyasmallproportionwhichdoso；andifwehadpassedintoanaerolite，itdoesnotnecessarilyfollowthatweshouldeverreachthesurfaceofthemoon。"
"Buthowifwegetnearenough？"repliedMichel。
"Puremistake，"repliedBarbicane。"Haveyounotseenshootingstarsrushthroughtheskybythousandsatcertainseasons？"
"Yes。"
"Well，thesestars，orrathercorpuscles，onlyshinewhentheyareheatedbyglidingovertheatmosphericlayers。Now，iftheyentertheatmosphere，theypassatleastwithinfortymilesoftheearth，buttheyseldomfalluponit。Thesamewithourprojectile。Itmayapproachveryneartothemoon，andnotyetfalluponit。"
"Butthen，"askedMichel，"Ishallbecurioustoknowhowourerringvehiclewillactinspace？"
"Iseebuttwohypotheses，"repliedBarbicane，aftersomemoments'reflection。
"Whatarethey？"
"Theprojectilehasthechoicebetweentwomathematicalcurves，anditwillfollowoneortheotheraccordingtothespeedwithwhichitisanimated，andwhichatthismomentIcannotestimate。"
"Yes，"saidNicholl，"itwillfolloweitheraparabolaorahyperbola。"
"Justso，"repliedBarbicane。"Withacertainspeeditwillassumetheparabola，andwithagreaterthehyperbola。"
"Ilikethosegrandwords，"exclaimedMichelArdan；"oneknowsdirectlywhattheymean。Andpraywhatisyourparabola，ifyouplease？"
"Myfriend，"answeredthecaptain，"theparabolaisacurveofthesecondorder，theresultofthesectionofaconeintersectedbyaplaneparalleltooneofthesides。"
"Ah！ah！"saidMichel，inasatisfiedtone。
"Itisverynearly，"continuedNicholl，"thecoursedescribedbyabomblaunchedfromamortar。"
"Perfect！Andthehyperbola？"
"Thehyperbola，Michel，isacurveofthesecondorder，producedbytheintersectionofaconicsurfaceandaplaneparalleltoitsaxis，andconstitutestwobranchesseparatedonefromtheother，bothtendingindefinitelyinthetwodirections。"
"Isitpossible！"exclaimedMichelArdaninaserioustone，asiftheyhadtoldhimofsomeseriousevent。"WhatIparticularlylikeinyourdefinitionofthehyperbolaIwasgoingtosayhyperblagueisthatitisstillmoreobscurethanthewordyoupretendtodefine。"
NichollandBarbicanecaredlittleforMichelArdan'sfun。
Theyweredeepinascientificdiscussion。Whatcurvewouldtheprojectilefollow？wastheirhobby。Onemaintainedthehyperbola，theothertheparabola。Theygaveeachotherreasonsbristlingwith_x_。TheirargumentswerecouchedinlanguagewhichmadeMicheljump。Thediscussionwashot，andneitherwouldgiveuphischosencurvetohisadversary。
ThisscientificdisputelastedsolongthatitmadeMichelveryimpatient。
"Now，gentlemencosines，willyouceasetothrowparabolasandhyperbolasateachother'sheads？Iwanttounderstandtheonlyinterestingquestioninthewholeaffair。Weshallfollowoneortheotherofthesecurves？Good。Butwherewilltheyleadusto？"
"Nowhere，"repliedNicholl。
"How，nowhere？"
"Evidently，"saidBarbicane，"theyareopencurves，whichmaybeprolongedindefinitely。"
"Ah，savants！"criedMichel；"andwhatareeithertheoneortheothertousfromthemomentweknowthattheyequallyleadusintoinfinitespace？"
BarbicaneandNichollcouldnotforbearsmiling。Theyhadjustbeencreating"artforart'ssake。"Neverhadsoidleaquestionbeenraisedatsuchaninopportunemoment。Thesinistertruthremainedthat，whetherhyperbolicallyorparabolicallyborneaway，theprojectilewouldneveragainmeeteithertheearthorthemoon。
Whatwouldbecomeoftheseboldtravelersintheimmediatefuture？
Iftheydidnotdieofhunger，iftheydidnotdieofthirst，insomedays，whenthegasfailed，theywoulddiefromwantofair，unlessthecoldhadkilledthemfirst。Still，importantasitwastoeconomizethegas，theexcessivelownessofthesurroundingtemperatureobligedthemtoconsumeacertainquantity。
Strictlyspeaking，theycoulddowithoutits_light_，butnotwithoutits_heat_。FortunatelythecaloricgeneratedbyReiset'sandRegnaut'sapparatusraisedthetemperatureoftheinterioroftheprojectilealittle，andwithoutmuchexpendituretheywereabletokeepitbearable。
Butobservationshadnowbecomeverydifficult。thedampnessoftheprojectilewascondensedonthewindowsandcongealedimmediately。
Thiscloudinesshadtobedispersedcontinually。Inanycasetheymighthopetobeabletodiscoversomephenomenaofthehighestinterest。
Butuptothistimethediscremaineddumbanddark。Itdidnotanswerthemultiplicityofquestionsputbytheseardentminds；
amatterwhichdrewthisreflectionfromMichel，apparentlyajustone:
"Ifeverwebeginthisjourneyoveragain，weshalldowelltochoosethetimewhenthemoonisatthefull。"
"Certainly，"saidNicholl，"thatcircumstancewillbemorefavorable。
Iallowthatthemoon，immersedinthesun'srays，willnotbevisibleduringthetransit，butinsteadweshouldseetheearth，whichwouldbefull。Andwhatismore，ifweweredrawnroundthemoon，asatthismoment，weshouldatleasthavetheadvantageofseeingtheinvisiblepartofherdiscmagnificentlylit。"
"Wellsaid，Nicholl，"repliedMichelArdan。"Whatdoyouthink，Barbicane？"
"Ithinkthis，"answeredthegravepresident:"Ifeverwebeginthisjourneyagain，weshallstartatthesametimeandunderthesameconditions。Supposewehadattainedourend，woulditnothavebeenbettertohavefoundcontinentsinbroaddaylightthanacountryplungedinutterdarkness？Wouldnotourfirstinstallationhavebeenmadeunderbettercircumstances？
Yes，evidently。Astotheinvisibleside，wecouldhavevisiteditinourexploringexpeditionsonthelunarglobe。Sothatthetimeofthefullmoonwaswellchosen。Butweoughttohavearrivedattheend；andinordertohavesoarrived，weoughttohavesufferednodeviationontheroad。"
"Ihavenothingtosaytothat，"answeredMichelArdan。
"Hereis，however，agoodopportunitylostofobservingtheothersideofthemoon。"
Buttheprojectilewasnowdescribingintheshadowthatincalculablecoursewhichnosight-markwouldallowthemtoascertain。Haditsdirectionbeenaltered，eitherbytheinfluenceofthelunarattraction，orbytheactionofsomeunknownstar？Barbicanecouldnotsay。Butachangehadtakenplaceintherelativepositionofthevehicle；andBarbicaneverifieditaboutfourinthemorning。
Thechangeconsistedinthis，thatthebaseoftheprojectilehadturnedtowardthemoon'ssurface，andwassoheldbyaperpendicularpassingthroughitsaxis。Theattraction，thatistosaytheweight，hadbroughtaboutthisalteration。Theheaviestpartoftheprojectileinclinedtowardtheinvisiblediscasifitwouldfalluponit。
Wasitfalling？Werethetravelersattainingthatmuchdesiredend？
No。Andtheobservationofasign-point，quiteinexplicableinitself，showedBarbicanethathisprojectilewasnotnearingthemoon，andthatithadshiftedbyfollowinganalmostconcentriccurve。
Thispointofmarkwasaluminousbrightness，whichNichollsightedsuddenly，onthelimitofthehorizonformedbytheblackdisc。Thispointcouldnotbeconfoundedwithastar。
Itwasareddishincandescencewhichincreasedbydegrees，adecidedproofthattheprojectilewasshiftingtowarditandnotfallingnormallyonthesurfaceofthemoon。
"Avolcano！itisavolcanoinaction！"criedNicholl；"adisembowelingoftheinteriorfiresofthemoon！Thatworldisnotquiteextinguished。"
"Yes，aneruption，"repliedBarbicane，whowascarefullystudyingthephenomenonthroughhisnightglass。"Whatshoulditbe，ifnotavolcano？"
"But，then，"saidMichelArdan，"inordertomaintainthatcombustion，theremustbeair。Sotheatmospheredoessurroundthatpartofthemoon。"
"Perhapsso，"repliedBarbicane，"butnotnecessarily。
Thevolcano，bythedecompositionofcertainsubstances，canprovideitsownoxygen，andthusthrowflamesintospace。Itseemstomethatthedeflagration，bytheintensebrilliancyofthesubstancesincombustion，isproducedinpureoxygen。Wemustnotbeinahurrytoproclaimtheexistenceofalunaratmosphere。"
Thefierymountainmusthavebeensituatedaboutthe45@southlatitudeontheinvisiblepartofthedisc；but，toBarbicane'sgreatdispleasure，thecurvewhichtheprojectilewasdescribingwastakingitfarfromthepointindicatedbytheeruption。
Thushecouldnotdetermineitsnatureexactly。Halfanhourafterbeingsighted，thisluminouspointhaddisappearedbehindthedarkhorizon；buttheverificationofthisphenomenonwasofconsiderableconsequenceintheirselenographicstudies。
Itprovedthatallheathadnotyetdisappearedfromthebowelsofthisglobe；andwhereheatexists，whocanaffirmthatthevegetablekingdom，nay，eventheanimalkingdomitself，hasnotuptothistimeresistedalldestructiveinfluences？Theexistenceofthisvolcanoineruption，unmistakablyseenbytheseearthlysavants，woulddoubtlessgiverisetomanytheoriesfavorabletothegravequestionofthehabitabilityofthemoon。
Barbicaneallowedhimselftobecarriedawaybythesereflections。
Heforgothimselfinadeepreverieinwhichthemysteriousdestinyofthelunarworldwasuppermost。Hewasseekingtocombinetogetherthefactsobserveduptothattime，whenanewincidentrecalledhimbrisklytoreality。Thisincidentwasmorethanacosmicalphenomenon；itwasathreateneddanger，theconsequenceofwhichmightbedisastrousintheextreme。
Suddenly，inthemidstoftheether，intheprofounddarkness，anenormousmassappeared。Itwaslikeamoon，butanincandescentmoonwhosebrilliancywasallthemoreintolerableasitcutsharplyonthefrightfuldarknessofspace。Thismass，ofacircularform，threwalightwhichfilledtheprojectile。
TheformsofBarbicane，Nicholl，andMichelArdan，bathedinitswhitesheets，assumedthatlividspectralappearancewhichphysiciansproducewiththefictitiouslightofalcoholimpregnatedwithsalt。
"ByJove！"criedMichelArdan，"wearehideous。Whatisthatill-conditionedmoon？"
"Ameteor，"repliedBarbicane。
"Ameteorburninginspace？"
"Yes。"