a journey in other worlds-第36章

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Superior；　and　that　several　large　and　small　streams　ran　into　its
upper　end。　　These　had　their　sources　in　smaller　lakes　that　were　at
slightly　higher　elevations。　　Though　the　air　was　cool；　the　sun
shone　brightly；　while　the　ground　was　covered　with　flowers
resembling　those　of　the　northern　climes　on　earth；　of　all　shapes
and　lines。　　Twice　a　day　these　sent　up　their　song；　and　trees　were
covered　with　buds；　and　the　birds　twittered　gaily。　　The　streams
murmured　and　bubbled；　and　all　things　reminded　the　travellers　of
early　morning　in　spring。
　　　
〃If　anything　could　reconcile　me；〃　said　Bearwarden；　〃to　exchange
my　active　utilitarian　life　for　a　rustic　poetical　existence；　it
would　be　this　place；　for　it　is　far　more　beautiful　than　anything　I
have　seen　on　earth。　　It　needs　but　a　Maud　Muller　and　a　few　cows　to
complete　the　picture；　since　Nature　gives　us　a　vision　of　eternal
peace　and　repose。〃
　　　
Somehow　the　mention　of　Maud　Muller；　and　the　delicate　and　refined
flowers；　whose　perfume　he　inhaled；　brought　up　thoughts　that　were
never　far　below　the　surface　in　Ayrault's　mind。　　〃The　place　is
heavenly　enough；〃　said　he；　〃to　make　one　wish　to　live　and　remain
here　forever；　but　to　me　it　would　be　Hamlet　with　Hamlet　left　out。〃
　　　
〃Ah！　poor　chap；〃　said　Cortlandt；　〃you　are　in　love；　but　you　are
not　to　be　pitied；　for　though　the　thrusts　at　the　heart　are　sharp；
they　may　be　the　sweetest　that　mortals　know。〃
　　　
The　following　morning　they　reluctantly　left　the　picturesque
shores　of　Lake　Serenity；　with　their　beautiful　tints　and　foliage；
and　resumed　the　journey；　to　explore　a　number　of　islands　in　the
ocean　in　the　west；　which　were　recorded　on　their　negatives。　
Ascending　to　rarefied　air；　they　saw　great　chains　of　mountains；
which　they　imagined　ran　parallel　to　the　coast；　rising　to
considerable　altitudes　in　the　east。　　The　tops　of　all　glistened
with　a　mantle　of　snow　in　the　sunlight；　while　between　the　ridges
they　saw　darker　and　evidently　fertile　valleys。　　They　passed；
moving　northwest；　over　large　and　small　lakes；　all　evidently　part
of　the　same　great　system；　and　continued　to　sweep　along　for
several　days　with　a　beautiful　panorama；　as　varying　as　a
kaleidoscope；　spread　beneath　their　eyes。　　They　observed　that　the
character　of　the　country　gradually　changed。　　The　symmetrically
rounded　mountains　and　hills　began　to　show　angles；　while　great
slabs　of　rock　were　split　from　the　faces。　　The　sides　also　became
less　vertical；　and　there　was　an　accumulation　of　detrital
fragments　about　their　bases。　　These　heaps　of　fractured　stone　had
in　some　cases　begun　to　disintegrate　and　form　soil；　on　which　there
was　a　scant　growth　of　vegetation；　but　the　sides　and　summits；
whose　jaggedness　increased　with　their　height；　were　absolutely
bare。
　　　
〃Here；〃　said　Cortlandt；　〃we　have　unmistakable　evidence　of　frost
and　ice　action。　　The　next　interesting　question　is；　How　recently
has　denudation　occurred？　　The　absence　of　plant　life　at　the
exposed　places；〃　he　continued；　as　if　lecturing　to　a　class；　〃can
be　accounted　for　here；　as　nearer　the　equator；　by　the　violence　of
the　wind；　but　I　greatly　doubt　whether　water　will　now　freeze　in
this　latitude　at　any　season　of　the　year；　for；　even　should　the
Northern　hemisphere's　very　insignificant　winter　coincide　with　the
planet's　aphelion；　the　necessary　drop　from　the　present
temperature　would　be　too　great　to　be　at　all　probable。　　If；　then；
it　is　granted　that　ice　does　not　form　here　now；　notwithstanding
the　fact　that　it　has　done　so；　the　most　plausible　conclusion　is
that　the　inclination　of　Jupiter's　axis　is　automatically　changing；
as　we　know　the　earth's　has　often　done。　　There　being　nothing
incompatible　in　this　view　with　the　evidence　at　hand；　we　can
safely　assume　it　correct　for　the　time　being　at　least。　　When
farther　south；　you　remember；　we　found　no　trace　of　ice　action；
notwithstanding　the　comparative　slowness　with　which　we　decided
that　the　ridges　in　the　crust　had　been　upheaved　on　account　of　the
resisting　power　of　gravity；　and；　as　I　see　now；　also　on　account　of
Jupiter's　great　mass；　which　must　prevent　its　losing　its　heat
anything　like　as　fast　as　the　earth　has；　in　which　I　think　also　we
have　the　explanation　of　the　comparatively　low　elevation　of　the
mountains　that　we　found　we　could　not　account　for　by　the　power　of
gravitation　alone。＇2＇　　From　the　fact　that　the　exposed　surface
farther　south　must　be　old；　on　account　of　the　slow　upheaval　and
the　slight　wear　to　which　it　is　exposed；　about　the　only　wearing
agent　being　the　wind；　which　would　be　powerless　to　erase
ice…scratches；　especially　since；　on　account　of　gravity's　power；
it　cannot；　like　our　desert　winds；　carry　much　sandwhich；　as　we
know；　has　cut　away　the　base　of　the　SphinxI　think　it　is　logical
to　conclude　that；　though　Jupiter's　axis　is　changing　naturally　as
the　earth's　has　been；　it　has　never　varied　as　much　as　twenty…three
and　a　half　degrees；　and　certainly　to　nothing　like　the　extent　to
which　we　see　Venus　and　Uranus　tilted　to…day。〃

＇2＇　　It　is　well　known　that　mountain　chains　are　but　ridges　or
foldings　in　the　crust　upheaved　as　the　interior　cools　and　shrinks。　
This　is　proved　by　reason　and　by　experiments　with　viscous　clay　or
other　material　placed　upon　a　sheet　of　stretched　rubber；　which　is
afterwards　allowed　to　contract；　whereupon　the　analogues　of
mountain　ridges　are　thrown　up。


〃I　follow　you；〃　said　Bearwarden；　〃and　do　not　see　how　we　could
arrive　at　anything　else。　　From　Jupiter's　low　specific　gravity；
weighing　but　little　more　than　an　equal　bulk　of　water；　I　should
say　the　interior　must　be　very　hot；　or　else　is　composed　of　light
material；　for　the　crust's　surface；　or　the　part　we　see；　is
evidently　about　as　dense　as　what　we　have　on　earth。　　These　things
have　puzzled　me　a　good　deal；　and　I　have　been　wondering　if　Jupiter
may　not　have　been　formed　before　the　earth　and　the　smaller
planets。〃
　　　
〃The　discrepancies　between　even　the　best　authorities；〃　replied
Cortlandt；　〃show　that　as　yet　but　little　has　been　discovered　from
the　earth　concerning　Jupiter's　real　condition。　　The　two　theories
that　try　to　account　for　its　genesis　are　the　ring　theory　and　the
nebulous。　　We　know　that　the　sun　is　constantly　emitting　vast
volumes　of　heat　and　light；　and　that；　with　the　exception　of　the
heat　resulting　from　the　impact　of　falling　meteors；　it　receives
none　from　outside；　the　principal　source　being　the　tremendous
friction　and　pressure　between　the　cooling　and　shrinking　strata
within　the　great　mass　of　the　sun　itself。　　A　seeming　paradox
therefore　comes　in　here；　which　must　be　considered：　　If　the　sun
were　composed　entirely　of　gas；　it　would　for　a　time　continue　to
grow　hotter；　but　the　sun　is　incessantly　radiating　light　and　heat；
and　consequently　becoming　smaller。　　Therefore　the　farther　back　we
go　the　hotter　we　find　the　sun；　and　also　the　larger；　till；　instead
of　having　a　diameter　of　eight　hundred　and　eighty　thousand　miles；
it　filled　the　space　now　occupied　by　the　entire　solar　system。　
Here　is　where　the　two　theories　start。　　According　to　the　first；
the　revolving　nebulous　mass　threw　off　a　ring　that　became　the
planet　Neptune；　afterwards　another　that　contained　the　material
for　Uranus；　and　so　on；　the　lightest　substance　in　the　sun　being
thrown　off　first；　by　which　they　accounted　for　the　lightness　of
the　four　great　planets；　and　finally　Mars；　the　earth；　and　the
small　dense　planets　near　the　sun。　　The　advocates　of　this　theory
pointed　to　Saturn's　rings　as　an　illustration　of　the　birth　of　a
planet；　or；　rather；　in　that　case　a　satellite。　　According　to　this；
the　major　planets　have　had　a　far　longer　separate　existence　than
the　minor；　which　would　account　for　their　being　so　advanced
notwithstanding　their　size。　　This　theory　may　again　come　into
general　acceptance；　but　for　the　present　it　has　been　discredited
by　the　nebulous。　　According　to　this　second　theory；　at　the　time
the　sun　filled　all　the　space　inside　of　Neptune's；　orbit；　or
extended　even　farther；　several　centres　of　condensation　were
formed　within　the　nebulous；　gaseous　mass。　　The　greatest　centre
became　the　sun；　and　the　others；　large　and　small；　the　planets；
whichas　a　result　of　the　spiral　motion　of　the　whole；　such　as　is
now　going　on　before　our　eyes　in　the　great　nebulae　of　fifty…　one
M。　Canuin　venaticorum；　and　many　othersbegan　to　revolve　about
the　greatest　centra