,is ,m>s ,habitable8 ,a ,,critical ,,exam9ation ,,( ,,pr(essor ,,p]cival ,,l[ell',s ,,book ,,m>s ,,& ,,its ,,canals1 ,,) ,,an ,,alt]native ,,explanation ,,by ,,alfr$ ,,russel ,,wallace ,f4,r4,s41 ,,etc4 ,,preface4 ,?is small volume 0 comm5c$ z a review article on ,pr(essor ,p]cival ,l[ell's book1 ,m>s & its ,canals1 ) ! object ( %[+ t ! l>ge am\nt ( new & int]e/+ facts conta9$ 9 ?is "w did n invalidate ! conclusion ,i _h rea*$ 9 #aijb1 & /at$ 9 my book on ,man's ,place 9 ! ,univ]se1 t ,m>s 0 n habitable4 ,b ! m complete pres5tation ( ! opposite view 9 ! volume n[ "u discussion requir$ a m detail$ exam9ation ( ! v>i\s physical problems involv$1 & z ! subject is "o ( great1 popul>1 z well z sci5tific int]e/1 ,i det]m9$ to und]take ! task4 ,?is 0 r5d]$ ! m necess>y by ! fact t 9 ,july la/ ,pr(essor ,l[ell publi%$ 9 ! ,philosophical ,magaz9e an elaborate ma!matical article claim+ to demon/rate t1 not)/&+ its mu* great] di/ance f ! sun & its excessively ?9 atmosph]e1 ,m>s possess$ a climate on ! av]age equal to t ( ! s\? ( ,engl&1 & 9 its pol> & sub-pol> regions ev5 less sev]e ?an t ( ! e>?4 ,su* a cont5tion ( c\rse requir$ to be dealt )1 & l$ me to collect in=mation be>+ ^u temp]ature 9 all its aspects1 & s enl>g+ my criticism t ,i saw x w\ld be necess>y to issue x 9 book =m4 ,two ( my ma!matical fri5ds h po9t$ out ! *ief omission :i* vitiates ,pr(essor ,l[ell's ma!matical conclusions--t ( a failure to recognise ! v l>ge cons]vative & cumulative effect ( a d5se atmosph]e4 ,?is v po9t h[ev] ,i _h already myself discuss$ 9 ,*apt] ,,vi41 & by means ( "s rem>kable rese>*es on ! heat ( ! moon & an inve/igation ( ! causes ( its v l[ temp]ature1 ,i h1 ,i ?9k1 demon/rat$ ! incorrectness ( ,mr4 ,l[ell's results4 ,9 my la/ *apt]1 9 :i* ,i briefly summ>ise ! :ole argum5t1 ,i h fur!r /r5g!n$ ! case = v sev]e cold 9 ,m>s1 by adduc+ ! rapid l[]+ ( temp]ature univ]sally caus$ by dim9ution ( atmosph]ic pressure1 z manife/$ 9 ! well-kn[n ph5om5on ( temp]ate climates at mod]ate heights ev5 close to ! equator1 cold climates at great] heights ev5 on ext5sive plateaux1 culm9at+ 9 arctic climates & p]petual sn[ at heights :]e ! air is /ill f> d5s] ?an x is on ! surface ( ,m>s4 ,?is argum5t itself is1 9 my op9ion1 conclusive2 b x is en=c$ by two o!rs equally complete1 nei!r ( :i* is adequately met by ,mr4 ,l[ell4 ,! c>eful exam9ation :i* ,i h be5 l$ to give to ! :ole ( ! ph5om5a :i* ,m>s pres5ts1 & especially to ! discov]ies ( ,mr4 ,l[ell1 has l$ me to :at ,i hope w be consid]$ a satisfactory physical explanation ( !m4 ,?is explanation1 :i* occupies ! :ole ( my sev5? *apt]1 is f\nd$ ^u a special mode ( orig9 = ,m>s1 d]iv$ f ! ,meteoritic ,hypo!sis1 n[ v widely adopt$ by a/ronom]s & physici/s4 ,!n1 by a comp>ison ) c]ta9 well-kn[n & widely spread geological ph5om5a1 ,i %[ h[ ! great features ( ,m>s--! 'canals' & 'oases'--may h be5 caus$4 ,?is *apt] w p]haps be ! mo/ int]e/+ to ! g5]al read]1 z furni%+ a q natural explanation ( features ( ! planet :i* h be5 t]m$ 'non-natural' by ,mr4 ,l[ell4 ,incid5tally1 also1 ,i h be5 l$ to an explanation ( ! highly volcanic nature ( ! moon's surface4 ,?is seems to me absolutely to require "s su* orig9 z ,sir ,george ,d>w9 has giv5 x1 & ?us furni%es corroborative pro( ( ! accuracy ( ! hypo!sis t our moon has _h an unique orig9 among ! kn[n satellites1 9 hav+ be5 ?r[n (f f ! e>? itself4 ,i am indebt$ to ,pr(essor ,j4 ,h4 ,poynt+1 ( ! ,univ]sity ( ,birm+ham1 = valuable sugge/ions on "s ( ! m difficult po9ts ( ma!matical physics "h discuss$1 & also = ! critical note 7at ! end ( ,*apt] ,v47 on ,pr(essor ,l[ell's e/imate ( ! temp]ature ( ,m>s4 ,,broad/one1 ,,dorset1 ,octob] #aijg4 ,,table ,,( ,,cont5ts4 ,,*apt] ,i4 ,,e>ly ,,obs]v]s ,,( ,,m>s1 --,m>s ! only planet ! surface ( :i* is di/9ctly visible --,e>ly obs]vation ( ! sn[-caps & seas --,! 'canals' se5 by ,s*iap>elli 9 #ahgg --,d\ble canals fir/ se5 9 #ahha --,r\nd spots at int]section ( canals se5 by ,pick]+ 9 #ahib --,confirm$ by ,l[ell 9 #ahid --,*anges ( col\r se5 9 #ahib & #ahid --,exi/5ce ( seas d\bt$ by ,pick]+ & ,b>n>d 9 #ahid4 ,,*apt] ,,ii4 ,,mr4 ,,l[ell',s ,,discov]ies ,,& ,,!ories1 --,obs]vatory at ,flag/aff1 ,arizona --,illu/rat$ book on 8 obs]vations ( ,m>s --,volume on ,m>s & its canals1 #aijf --,non-natural features --,! canals z irrigation works ( an intellig5t race --,a *all5ge to ! ?9k+ _w --,! canals z describ$ & mapp$ by ,mr4 ,l[ell --,! d\ble canals --,dim5sions ( ! canals --,!y cross ! suppos$ seas --,circul> black spots t]m$ oases --,an int]e/+ volume4 ,,*apt] ,,iii4 ,,! ,,climate ,,& ,,physiography ,,( ,,m>s1 --,no p]man5t wat] on ,m>s --,r>ely any cl\ds & no ra9 --,sn[-caps ! only s\rce ( wat] --,no m\nta9s1 hills1 or valleys on ,m>s --,two-?irds ( ! surface a des]t --,wat] f ! sn[-caps too scanty to supply ! canals --,miss ,cl]ke's views z to ! wat]-supply --,description ( "s ( ! *ief canals --,mr4 ,l[ell on ! purpose ( ! canals --,rem>ks on ! same --,mr4 ,l[ell on relation ( canals to oases & sn[-caps --,critical rem>ks on ! same4 ,,*apt] ,,iv4 ,,is ,,animal ,,life ,,possible ,,on ,,m>s8 --,wat] & air ess5tial = animal life --,atmosph]e ( ,m>s assum$ to be l ours --,blue t9t ne> melt+ sn[ ! only evid5ce ( wat] --,fallacy ( ?is argum5t --,dr4 ,john/one ,/oney's pro( t wat]-vap\r _c exi/ on ,m>s --,spectroscope gives no evid5ce ( wat]4 ,,*apt] ,v4 ,,temp]ature ,,( ,,m>s--,,mr4 ,,l[ell',s ,,e/imate1 --,problem ( t]re/rial temp]ature --,ice "u rec5t lava --,tropical oceans ice-cold at bottom --,e>?'s surface-heat all f ! sun --,absolute z]o ( temp]ature --,complex problem ( planet>y temp]atures --,mr4 ,l[ell's inve/igation ( ! problem --,ab/ract ( ,mr4 ,l[ell's pap] --,critical rem>ks on ,mr4 ,l[ell's pap]4 ,,*apt] ,,vi4 ,a ,,new ,,e/imate ,,( ,,! ,,temp]ature ,,( ,,m>s1 --,langley's det]m9ation ( lun> heat --,rapid loss ( heat by radiation on ! e>? --,rapid loss ( heat on moon dur+ eclipse --,sir ,george ,d>w9's !ory ( ! moon's orig9 --,v's rese>*es on ! moon's temp]ature --,application ( ^! results to ! case ( ,m>s --,cause ( great diff]5ce ( temp]atures ( e>? & moon --,special features ( ,m>s influ5c+ its temp]ature --,fur!r criticism ( ,mr4 ,l[ell's article --,v l[ temp]ature ( arctic regions on ,m>s4 ,,*apt] ,,vii4 ,a ,,sugge/ion ,,z ,,to ,,! ',,canals' ,,( ,,m>s1 --,special features ( ! canals --,mr4 ,pick]+'s sugge/$ explanation --,! meteoritic hypo!ses ( orig9 ( planets --,probable mode ( orig9 ( ,m>s --,/ructural /raight l9es on ! e>? --,probable orig9 ( ! surface-features ( ,m>s --,symmetry ( basaltic columns --,h[ ?is applies to ,m>s --,sugge/$ explanation ( ! oases --,probable function ( ! great fissures --,sugge/$ orig9 ( blue pat*es adjac5t to sn[-caps --,! d\ble canals --,conclud+ rem>ks on ! canals4 ,,*apt] ,,viii4 ,,page ,,summ>y ,,& ,,conclusion1 --,! canals ! orig9 ( ,mr4 ,l[ell's !ory --,be/ expla9$ z natural features --,evaporation difficulty n met by ,mr4 ,l[ell --,h[ did ,m>tians live )\t ! canals --,radiation due to scanty atmosph]e n tak5 acc\nt ( --,?ree indep5d5t pro(s ( l[ temp]ature & un9habitability ( ,m>s --,conclusion4 ,,*apt] ,i4 ,,e>ly ,,obs]v]s ,,( ,,m>s4 ,few p]sons except a/ronom]s fully realise t ( all ! planets ( ! ,sol> sy/em ! only "o ^: solid surface has be5 se5 ) c]ta9ty is ,m>s2 &1 v =tunately1 t is also ! only "o :i* is suffici5tly ne> to u = ! physical features ( ! surface to be det]m9$ ) any accuracy1 ev5 if we c\ld see x 9 ! o!r planets4 ,( ,v5us we probably see only ! upp] surface ( its cl\dy atmosph]e4#a ,z reg>ds ,jupit] & ,saturn ?is is /ill m c]ta91 s9ce _! l[ d5sity w only p]mit ( a comp>atively small proportion ( _! huge bulk be+ solid4 ,_! belts are b ! cl\d-/rata ( _! upp] atmosph]e1 p]haps ?\s&s ( miles above _! solid surfaces1 & a some:at simil> condition seems to prevail 9 ! f> m remote planets ,uranus & ,neptune4 ,x has ?us happ5$1 t1 al?\gh z telescopic objects ( int]e/ & beauty1 ! m>vell\s r+s ( ,saturn1 ! belts & ev]-*ang+ aspects ( ! satellites ( ,jupit]1 & ! moon-l phases ( ,v5us1 toge!r ) its extreme brilliancy1 /ill rema9 unsurpass$1 yet ! great] am\nt ( details ( ^! features :5 exam9$ ) ! p[]ful in/rum5ts ( ! n9ete5? c5tury h nei!r add$ mu* to our k ( ! planets !mselves or l$ to any s5sational !ories calculat$ to attract ! popul> imag9ation4 ,footnote #a3 ,m]cury also seems to h a scanty atmosph]e1 b z its mass is only "o-?irtie? t ( ! e>? x c reta9 only ! heavi] gases1 & its atmosph]e may be du/-lad51 z is t ( ,m>s1 accord+ to ,mr4 ,l[ell4 ,its dusky m>k+s1 z se5 by ,s*iap>elli1 seem to be p]man5t1 & !y are also = consid]able p]iods un*angeable 9 position1 indicat+ t ! planet keeps ! same face t[>ds ! sun z does ,v5us4 ,?is 0 confirm$ by ,mr4 ,l[ell 9 #ahif4 ,its di/ance f u & unfav\rable position = obs]vation mu/ prev5t u f obta9+ any detail$ k ( its actual surface1 ?\gh its l[ reflective p[] indicates t ! surface may be really visible4 ,b 9 ! case ( ,m>s ! progress ( discov]y has _h a v diff]5t result4 ,! mo/ obvi\s peculi>ity ( ?is planet--its pol> sn[-caps--7 se5 ab\t #bej ye>s ago1 b !y 7 fir/ prov$ to increase & decrease alt]nately1 9 ! summ] & w9t] ( ea* hemisph]e1 by ,sir ,william ,h]s*ell 9 ! latt] "p ( ! eighte5? c5tury4 ,?is fact gave ! impulse to t idea ( simil>ity 9 ! conditions ( ,m>s & ! e>?1 :i* ! recognition ( _m l>ge dusky pat*es & /reaks z wat]1 & ! m ruddy & bright] portions z l&1 fur!r increas$4 ,add$ to ?is1 a day only ab\t half an h\r long] ?an our own1 & a succession ( seasons ( ! same "* z ours b ( ne>ly d\ble ! l5g? ow+ to its mu* long] ye>1 seem$ to leave little want+ to r5d] ?is planet a true e>? on a small] scale4 ,x 0 !re=e v natural to suppose t x mu/ be inhabit$1 & t we %\ld "s day obta9 evid5ce ( ! fact4 ,! ,canals discov]$ by ,s*iap>elli4 ,h5ce ! great int]e/ excit$ :5 ,s*iap>elli1 at ! ,milan ,obs]vatory1 dur+ ! v fav\rable opposition ( #ahgg & #ahgi1 obs]v$ t ! :ole ( ! tropical & temp]ate regions f #fj ,n4 to #fj ,s4 ,lat4 7 cov]$ ) a rem>kable network ( broad] curv$ & n>r[] /raight l9es ( a d>k col\r4 ,at ea* successive fav\rable opposition1 ^! /range objects call$ canali 7*annels7 by _! discov]]1 b r mislead+ly 'canals' 9 ,engl& & ,am]ica1 7 obs]v$ by means ( all ! great telescopes 9 ! _w1 & _! reality & g5]al features became well e/abli%$4 ,9 ,s*iap>elli's fir/ map !y 7 repres5t$ z be+ mu* broad] & less %>ply def9$ ?an he himself & o!r obs]v]s f\nd by lat] & equally fav\rable obs]vations t !y really 74 ,discov]y ( ! ,d\ble ,canals4 ,9 #ahha ano!r /range feature 0 discov]$ by ,s*iap>elli1 :o f\nd t ab\t tw5ty canals :i* _h previ\sly be5 se5 s+le 7 n[ di/9ctly d\ble1 t is1 t !y consi/$ ( two p>allel l9es1 equally di/9ct & ei!r v close toge!r or a consid]able di/ance ap>t4 ,?is curi\s appe>ance 0 at fir/ ?\ght to be due to "s in/rum5tal defect or optical illusion2 b z x 0 soon confirm$ by o!r obs]v]s ) ! be/ in/rum5ts & 9 widely diff]5t localities x became 9 "t accept$ z a real ph5om5on ( ! planet's surface4 ,r\nd ,spots discov]$ 9 #ahib4 ,at ! fav\rable opposition ( #ahib1 ,mr4 ,w4 ,h4 ,pick]+ notic$ t besides ! 'seas' ( v>i\s sizes !re 7 num]\s v small black spots app>5tly q circul> & occurr+ at e int]section or />t+-po9t ( ! 'canals4' ,_m ( ^! _h be5 se5 by ,s*iap>elli z l>g] & ill-def9$ d>k pat*es1 & 7 t]m$ seas or lakes2 b ,mr4 ,pick]+'s obs]vatory 0 at ,arequipa 9 ,p]u1 ab\t #hjjj feet above ! sea1 & ) su* p]fect atmosph]ic conditions z 71 9 8 op9ion1 equal to a d\bl+ ( telescopic ap]ture4 ,!y 7 soon detect$ by o!r obs]v]s1 especially by ,mr4 ,l[ell 9 #ahid1 :o ?us wrote ( !m3 ,scatt]$ ov] ! orange-o*re gr\ndwork ( ! cont95tal regions ( ! planet1 are any numb] ( d>k r\nd spots4 ,h[ _m !re may be x is n possible to /ate1 z ! bett] ! see+1 ! m ( !m !re seem to be4 ,9 spite1 h[ev]1 ( _! great numb]1 !re is no in/ance ( "o unconnect$ ) a canal4 ,:at is m1 !re is app>5tly none t does n lie at ! junction ( sev]al canals4 ,rev]sely1 all ! junctions appe> to be provid$ ) spots4 ,plott$ ^u a globe !y & _! connect+ canals make a mo/ curi\s network ov] all ! orange-o*re equatorial p>ts ( ! planet1 a mass ( l9es & knots1 ! "o m>k+ be+ z omnipres5t z ! o!r4 ,*anges ( ,col\r recognis$4 ,dur+ ! oppositions ( #ahib & #ahid x 0 fully recognis$ t a regul> c\rse ( *ange occurr$ dep5d5t ^u ! succession ( ! seasons1 z _h be5 fir/ sugge/$ by ,s*iap>elli4 ,z ! pol> sn[s melt ! adjac5t seas appe> to ov]fl[ & spread out z f> z ! tropics1 & are (t5 se5 to assume a di/9ctly gre5 col\r4 ,^! rem>kable *anges & ! extraord9>y ph5om5a ( p]fect /raight l9es cross+ ea* o!r ov] a l>ge portion ( ! planet's surface1 ) ! circul> spots at _! int]sections1 _h su* an appe>ance ( artificiality t ! idea t !y 7 really 'canals' made by intellig5t be+s = purposes ( irrigation1 0 fir/ h9t$ at1 & !n adopt$ z ! only intelligible explanation1 by ,mr4 ,l[ell & a few o!r p]sons4 ,?is at once seiz$ ^u ! public imag9ation & 0 spread by ! newspap]s & magaz9es ov] ! :ole civilis$ _w4 ,exi/5ce ( ,seas d\bt$4 ,at ?is "t 7#ahid7 x began to be d\bt$ :e!r !re 7 any seas at all on ,m>s4 ,pr(essor ,pick]+ ?\ght !y 7 f> m limit$ 9 size ?an _h be5 suppos$1 & ev5 might n exi/ z true seas4 ,pr(essor ,b>n>d1 ) ! ,lick ?irty-six in* telescope1 disc]n$ an a/oni%+ weal? ( detail on ! surface ( ,m>s1 s intricate1 m9ute1 & abundant1 t x baffl$ all attempts to del9eate x2 & ^! peculi>ities 7 se5 ^u ! suppos$ seas z well z on ! l&-surfaces4 ,9 fact1 "u ! be/ conditions ^! 'seas' lo/ all trace ( uni=mity1 _! appe>ance be+ t ( a m\nta9\s c\ntry1 brok5 by ridges1 rifts1 & canyons1 se5 f a great elevation4 ,z we %all see lat] on ^! d\bts soon became c]ta9ties1 & x is n[ almo/ univ]sally admitt$ t ,m>s possesses no p]man5t bodies ( wat]4 ,,*apt] ,,ii4 ,,mr4 ,,p]cival ,,l[ell',s ,,discov]ies ,,& ,,!ories4 ,! ,obs]vatory 9 ,arizona4 ,9 #ahid1 aft] a c>eful se>* = ! be/ atmosph]ic conditions1 ,mr4 ,l[ell e/abli%$ 8 obs]vatory ne> ! t[n ( ,flag/aff 9 ,arizona1 9 a v dry & uni=m climate1 & at an elevation ( #gcjj feet above ! sea4 ,he !n possess$ a f9e equatorial telescope ( #ah in*es ap]ture & #bf feet focal l5g?1 besides two small] ones1 all ( ! be/ quality4 ,to ^! he add$ 9 #ahif a telescope ) #bd in* object glass1 ! la/ "w ( ! celebrat$ firm ( ,alvan ,cl>k ,sons1 ) :i* he has made 8 lat] discov]ies4 ,he ?us became p]haps m fav\rably situat$ ?an any a/ronom] 9 ! nor!rn hemisph]e1 & dur+ ! la/ twelve ye>s has made a specialty ( ! /udy ( ,m>s1 besides do+ mu* valuable a/ronomical "w on o!r planets4 ,mr1 ,l[ell's rec5t ,books ^u ,m>s4 ,9 #aije ,mr4 ,l[ell publi%$ an illu/rat$ volume giv+ a full acc\nt ( 8 obs]vations ( ,m>s f #ahid to #aijc1 *iefly = ! use ( a/ronom]s2 & he has n[ giv5 u a popul> volume summ>is+ ! :ole ( 8 "w on ! planet1 & publi%$ bo? 9 ,am]ica & ,engl& by ! ,macmillan ,company4 ,?is v int]e/+ volume is fully illu/rat$ ) tw5ty plates1 f\r ( !m col\r$1 & m ?an =ty figures 9 ! text1 %[+ ! great v>iety ( details f :i* ! l>g] g5]al maps h be5 con/ruct$4 ,non-natural ,features ( ,m>s4 ,b :at r5d]s ?is "w especially int]e/+ to all intellig5t read]s is1 t ! au?or has "h1 = ! fir/ "t1 fully set =? 8 views bo? z to ! habitability ( ,m>s & z to its be+ actually inhabit$ by be+s comp>able ) ourselves 9 intellect4 ,! l>g] "p ( ! "w is 9 fact devot$ to a detail$ description ( :at he t]ms ! ',non-natural ,features' ( ! planet's surface1 includ+ especially a full acc\nt ( ! ',canals1' s+le & d\ble2 ! ',oases1' z he t]ms ! d>k spots at _! int]sections2 & ! v>y+ visibility ( bo?1 dep5d+ p>tly on ! ,m>tian seasons2 :ile ! five conclud+ *apt]s deal ) ! possibility ( animal life & ! evid5ce 9 fav\r ( x4 ,he also upholds ! !ory ( ! canals hav+ be5 con/ruct$ = ! purpose ( 'husb&+' ! scanty wat]-supply t exi/s2 & ?r\gh\t ! :ole ( ?is argum5t he cle>ly %[s t he consid]s ! evid5ce to be satisfactory1 & t ! only intelligible explanation ( ! :ole ( ! ph5om5a he s cle>ly sets =? is1 t ! inhabitants ( ,m>s h c>ri$ out on _! small & naturally inhospitable planet a va/ sy/em ( irrigation-works1 f> great] bo? 9 its ext5t1 9 its utility1 & its effect ^u _! _w z a habitation = civilis$ be+s1 ?an any?+ we h yet done ^u our e>?1 :]e our de/ructive ag5cies are p]haps m prom95t ?an ^? ( an improv+ & recup]ative "*4 ,a ,*all5ge to ! ,?9k+ ,_w4 ,?is volume is !re=e 9 ! nature ( a *all5ge1 n s mu* to a/ronom]s z to ! educat$ _w at l>ge1 to inve/igate ! evid5ce = s port5t\s a conclusion4 ,to d ?is requires only a g5]al acqua9tance ) mod]n sci5ce1 m especially ) me*anics & physics1 :ile ! ma9 cont5tion 7) :i* ,i %all *iefly deal7 t ! features t]m$ 'canals' are really works ( art & necessitate ! pres5ce ( intellig5t organic be+s1 requires only c>e & judgm5t 9 draw+ conclusions f admitt$ facts4 ,z ,i h already paid "s att5tion to ?is problem & h express$ ! op9ion t ,m>s is n habitable1#b judg+ f ! evid5ce !n available1 & z few m5 ( sci5ce h ! leisure requir$ = a c>eful exam9ation ( s speculative a subject1 ,i propose "h to po9t out :at ! facts1 z /at$ by ,mr4 ,l[ell himself1 d n r5d] ev5 probable mu* less prove4 ,incid5tally1 ,i may be able to adduce evid5ce ( a m or less weighty "*1 :i* seems to negative ! possibility ( any high =m ( animal life on ,m>s1 &1 a =tiori1 ! developm5t ( su* life z might culm9ate 9 a be+ equal or sup]ior to ourselves4 ,z mo/ popul> works on ,a/ronomy = ! la/ t5 ye>s at lea/1 z well z _m sci5tific p]iodicals & popul> magaz9es1 h reproduc$ "s ( ! maps ( ,m>s by ,s*iap>elli1 ,l[ell1 & o!rs1 ! g5]al appe>ance ( its surface w be famili> to mo/ read]s1 :o w ?us be fully able to appreciate ,mr4 ,l[ell's acc\nt ( 8 own fur!r discov]ies :i* ,i may h to quote4 ,"o ( ! be/ ( ^! maps ,i am able to give z a frontispiece to ?is volume1 & to ?is ,i %all ma9ly ref]4 ,footnote #b3 ,man's ,place 9 ! ,univ]se p4 #bfg 7#aijc74 ,! ,canals z describ$ by ,mr4 ,l[ell4 ,9 ! cle> atmosph]e ( ,arizona1 ,mr4 ,l[ell has be5 able on v>i\s fav\rable occasions to detect a network ( /raight l9es1 meet+ or cross+ ea* o!r at v>i\s angles1 & (t5 ext5d+ to a ?\s& or ev5 ov] two ?\s& miles 9 l5g?4 ,!y are se5 to cross bo? ! light & ! d>k regions ( ! planet's surface1 (t5 ext5d+ up to or />t+ f ! pol> sn[-caps4 ,mo/ ( ^! l9es are s f9e z only to be visible on special occasions ( atmosph]ic cle>ness & /ead9ess1 :i* h>dly ev] occur at l[l& /ations1 ev5 ) ! be/ in/rum5ts1 & almo/ all are se5 to be z p]fectly /raight z if drawn ) a rul]4 ,! ,d\ble ,canals4 ,"u exceptionally fav\rable conditions1 _m ( ! l9es t h be5 already se5 s+le appe> d\ble--a pair ( equally f9e l9es exactly p>allel ?r\gh\t _! :ole l5g?1 & appe>+1 z ,mr4 ,l[ell says1 cle> cut ^u ! disc1 its tw9 l9es l ! rails ( a railway track4 ,bo? ,s*iap>elli & ,l[ell 7 at fir/ s surpris$ at ?is ph5om5on t !y ?\ght x mu/ be an optical illusion1 & x 0 only aft] _m obs]vations 9 diff]5t ye>s1 & by ! application ( e conceivable te/1 t !y bo? became conv9c$ t !y witness$ a real feature ( ! planet's surface4 ,mr4 ,l[ell says he has n[ se5 !m hundr$s ( times1 & t 8 fir/ view ( "o 0 '! mo/ />tl+ly impressive' sight he has ev] witness$4 ,dim5sions ( ! ,canals4 ,a few dim5sions ( ^! /range objects mu/ be giv5 9 ord] t read]s may appreciate _! full /rang5ess & inexplicability4 ,out ( m ?an f\r hundr$ canals se5 & record$ by ,mr4 ,l[ell1 fifty-"o1 or ab\t "o eigh?1 are ei!r con/antly or occasionally se5 to be d\ble1 ! appe>ance ( duplicity be+ m or less p]iodical4 ,( 'canals' g5]ally1 ,mr4 ,l[ell /ates t !y v>y 9 l5g? f a few hundr$ to a few ?\s& miles long1 "o ( ! l>ge/ be+ ! ,phison1 :i* he t]ms 'a typical d\ble canal1' & :i* is said to be #bbej miles long1 :ile ! di/ance betwe5 its two con/itu5ts is ab\t #acj miles4#c ,! actual wid? ( ea* canal is f a m9imum ( ab\t a mile up to sev]al miles1 9 "o case ov] tw5ty4 ,a great feature ( ! d\bles is1 t !y are /rictly p>allel ?r\gh\t _! :ole c\rse1 & t 9 almo/ all cases !y are s truly /raight z to =m p>ts ( a great circle ( ! planet's sph]e4 ,a few h[ev] foll[ a gradual b v di/9ct curve1 & su* ( ^! z are d\ble pres5t ! same /rict p>allelism z ^? :i* are /raight4 ,footnote #c3 ,?is is on ! opposite side ( ,m>s f t %[n 9 ! frontispiece4 ,canals ext5d across ! ,seas4 ,x 0 only aft] sev5te5 ye>s ( obs]vation ( ! canals t x 0 f\nd t !y ext5d$ also into & across ! d>k spots & surfaces :i* by ! e>li] obs]v]s 7 t]m$ seas1 & :i* !n =m$ ! only cle>ly di/+ui%able & p]man5t m>ks on ! planet's surface4 ,at ! pres5t "t1 ,pr(essor ,l[ell /ates t ?is curi\s triangulation has be5 trac$ ov] almo/ e portion ( ! planet's surface1 :e!r d>k or light1 :e!r gre5i%1 o*re1 or br[n 9 col\r4 ,9 "s p>ts !y are mu* clos] toge!r ?an 9 o!rs1 =m+ a p]fect network ( l9es & spots1 s t to id5tify !m all 0 a matt] ( extreme difficulty4 ,two su* portions are figur$ at pages #bdg & #bef ( ,mr4 ,l[ell's volume4 ,! ,oases4 ,! curi\s circul> black spots :i* are se5 at ! int]sections ( _m ( ! canals1 & :i* 9 "s p>ts ( ! surface are v num]\s1 are said to be m difficult ( detection ?an ev5 ! l9es1 be+ (t5 blurr$ or r5d]$ completely invisible by slight irregul>ities 9 our own atmosph]e1 :ile ! canals !mselves cont9ue visible4 ,ab\t #ahj ( ^! h n[ be5 f\nd1 & ! m prom95t ( !m are e/imat$ to v>y f #ge to #ajj miles 9 diamet]4 ,!re are h[ev] _m mu* small]1 d[n to m9ute & b>ely visible black po9ts4 ,yet !y all seem a little l>g] ?an ! canals :i* ent] !m4 ,:]e ! canals are d\ble1 ! spots 7or 'oases' z ,mr4 ,l[ell t]ms !m7 lie betwe5 ! two p>allel canals4 ,no "o c read ?is book )\t admiration = ! extreme p]sev]ance 9 long cont9u$ & successful obs]vation1 ! results ( :i* are "h record$2 & ,i myself accept unres]v$ly ! sub/antial accuracy ( ! :ole s]ies4 ,x mu/ h[ev] always be rememb]$ t ! gr[? ( k ( ! detail$ m>k+s has be5 v gradual1 & t mu* ( x has only be5 se5 "u v r>e & exceptional conditions4 ,x is !re=e q possible t1 if at "s future "t a fur!r consid]able advance 9 in/rum5tal p[] %\ld be made1 or a /ill m fav\rable locality be f\nd1 ! new discov]ies might s modify pres5t appe>ances z to r5d] a satisfactory explanation ( !m m easy ?an x is at pres5t4 ,b ?\gh ,i wi% to d ! fulle/ ju/ice to ,mr4 ,l[ell's te*nical skill & long ye>s ( p]sev]+ "w1 :i* h br\ght to light ! mo/ complex & rem>kable appe>ances t any ( ! heav5ly bodies pres5t to u1 ,i am oblig$ absolutely to "p company ) him z reg>ds ! />tl+ !ory ( artificial production :i* he ?9ks alone adequate to expla9 !m4 ,s mu* is ?is ! case1 t ! v ph5om5a1 :i* to him seem to demon/rate ! int]v5tion ( intellig5t be+s work+ = ! improvem5t ( _! own environm5t1 are ^? :i* seem to me to be> ! unmi/akable impress ( be+ due to natural =ces1 :ile !y are :olly un9telligible z be+ useful works ( art4 ,i ref] ( c\rse to ! great sy/em ( :at are t]m$ 'canals1' :e!r s+le or d\ble4 ,( ^! ,i %all give my own int]pretation lat] on4 ,,*apt] ,,iii4 ,,! ,,climate ,,& ,,physiography ,,( ,,m>s4 ,mr4 ,l[ell admits1 & inde$ urges /rongly1 t !re are no p]man5t bodies ( wat] on ,m>s2 t ! d>k spaces & spots1 ?\ght by ! e>ly obs]v]s to be seas1 are c]ta9ly n s n[1 ?\gh !y may h be5 at an e>li] p]iod2 t true cl\ds are r>e1 ev5 if !y exi/1 ! appe>ances t h be5 tak5 = !m be+ ei!r du/-/orms or a surface haze2 t !re is consequ5tly no ra91 & t l>ge portions 7ab\t two-?irds7 ( ! planet's surface h all ! *>act]i/ics ( des]t regions4 ,sn[-caps ! only ,s\rce ( ,wat]4 ,?is /ate ( ?+s is suppos$ to be ameliorat$ by ! fact ( ! pol> sn[s1 :i* 9 ! w9t] cov] ! arctic & ab\t half ! temp]ate regions ( ea* hemisph]e alt]nately4 ,! maximum ( ! nor!rn sn[-caps is rea*$ at a p]iod ( ! ,m>tian w9t] correspond+ to ! end ( ,febru>y ) u4 ,ab\t ! end ( ,m>* ! cap beg9s to %r9k 9 size 79 ! ,nor!rn ,hemisph]e71 & ?is goes on s rapidly t e>ly 9 ! ,june ( ,m>s x is r$uc$ to its m9imum4 ,ab\t ! same "t *anges ( col\r take place 9 ! adjac5t d>k] portions ( ! surface1 :i* become at fir/ blui%1 & lat] a decid$ blue-gre52 b by f> ! l>g] portion1 includ+ almo/ all ! equatorial regions ( ! planet1 rema9 always ( a r$di%-o*re t9t4#d ,footnote #d3 ,9 #ahij at ,m\nt ,wilson1 ,cali=nia1 ,mr4 ,w4,h4 ,pick]+'s photographs ( ,m>s on ,april #i? %[$ ! s\!rn pol> cap ( mod]ate dim5sions1 b ) a l>ge dim adjac5t area4 ,tw5ty-f\r h\rs lat] a correspond+ plate %[$ ?is same area brilliantly :ite2 ! result app>5tly ( a great ,m>tian sn[fall4 ,9 #ahhb ! same obs]v] witness$ ! /eady disappe>ance ( #a1fjj1jjj squ>e miles ( ! s\!rn sn[-cap1 an area ne>ly "o-?ird ( t hemisph]e ( ! planet4 ,! rapid & comp>atively e>ly disappe>ance ( ! :ite cov]+ is1 v reasonably1 suppos$ to prove t x is ( small ?ickness1 correspond+ p]haps to ab\t a foot or two ( sn[ 9 nor?-temp]ate ,am]ica & ,europe1 & t by ! increas+ am\nt ( sun-heat x is conv]t$1 p>tly into liquid & p>tly into vap\r4 ,co9cid5t ) ?is disappe>ance & z a presum$ result ( ! wat] 7or o!r liquid7 produc+ inundations1 ! blui%-gre5 t+e :i* appe>s on ! previ\sly d>k portion ( ! surface is suppos$ to be due to a rapid gr[? ( vegetation4 ,b ! evid5ce on ?is po9t does n seem to be cle> or h>moni\s1 = 9 ! f\r col\r$ plates %[+ ! planet's surface at successive ,m>tian dates f ,decemb] #cj? to ,febru>y #ba/1 n only is a consid]able ext5t ( ! s\? temp]ate zone %[n to *ange rapidly f blui%-gre5 to *ocolate-br[n & !n aga9 to blui%-gre51 b ! portions fur!/ f ! suppos$ f]tilis+ ov]fl[ are p]man5tly gre51 z are also consid]able portions 9 ! opposite or nor!rn hemisph]e1 :i* "o w\ld ?9k w\ld !n be completely dri$ up4 ,no ,hills ^u ,m>s4 ,! special po9t to :i* ,i "h wi% to call att5tion is ?is4 ,mr4 ,l[ell's ma9 cont5tion is1 t ! surface ( ,m>s is wond]fully smoo? & level4 ,n only are !re no m\nta9s1 b !re are no hills or valleys or plateaux4 ,?is assumption is absolutely ess5tial to support ! o!r great assumption1 t ! wond]ful network ( p]fectly /raight l9es ov] ne>ly ! :ole surface ( ! planet are irrigation canals4 ,x is n alleg$ t irregul>ities or undulations ( a few hundr$s or ev5 "o or two ?\s&s ( feet c\ld possibly be detect$1 :ile c]ta9ly all we "k ( planet>y =mation or /ructure po9t /rongly t[>ds "s inequalities ( surface4 ,mr4 ,l[ell admits t ! d>k portions ( ! surface1 :5 exam9$ on ! t]m9ator 7! m>g9 ( ! illum9at$ portion71 d look l holl[s & may be ! b$s ( dri$-up seas2 yet ! suppos$ canals run across ^! old sea-b$s 9 p]fect /raight l9es j z !y d across ! _m ?\s& miles ( :at are admitt$ to be des]ts--:i* he describes 9 ^! =cible t]ms3 ,pitiless z our des]ts are1 !y are b fa9t =eca/s ( ! /ate ( ?+s exi/5t on ,m>s at ! pres5t "t4 ,x appe>s1 !n1 t ,mr4 ,l[ell has to face ?is dilemma--,only if ! :ole surface ( ,m>s is an almo/ p]fect level c\ld ! enorm\s network ( /raight canals1 ea* f hundr$s to ?\s&s ( miles long1 h be5 possibly con/ruct$ by intellig5t be+s = purposes ( irrigation2 b1 if a complete & univ]sal level surface exi/s no su* sy/em w\ld be necess>y4 ,= on a level surface--or on a surface slightly incl9$ f ! poles t[>ds ! equator1 :i* w\ld be advantage\s 9 ei!r case--! melt+ wat] w\ld ( itself spread ov] ! gr\nd & naturally irrigate z mu* ( ! surface z x 0 possible = x to rea*4 ,if ! surface 7 n level1 b consi/$ ( slight elevations & expressions to ! ext5t ( a few scores or a few hundr$s ( feet1 !n !re w\ld be no possible advantage 9 cutt+ /raight tr\ghs ?r\gh ^! elevations 9 v>i\s directions ) wat] fl[+ at ! bottom ( !m4 ,9 nei!r case1 & 9 h>dly any conceivable case1 c\ld ^! p]fectly /raight canals1 cutt+ across ea* o!r 9 e direction & at v v>y+ angles1 be ( any use1 or be ! "w ( an intellig5t race1 if any su* race c\ld possibly h be5 develop$ "u ! adv]se conditions :i* exi/ 9 ,m>s4 ,! ,scanty ,wat]-supply4 ,b fur!r1 if !re 7 any sup]fluity ( wat] d]iv$ f ! melt+ sn[ beyond :at 0 suffici5t to moi/5 ! holl[s indicat$ by ! d>k] portions ( ! surface1 :i* at ! "t ! wat] rea*es !m acquire a gre5 t9t 7a sup]fluity "u ! circum/ances highly improbable71 t sup]fluity c\ld be be/ utilis$ by wid5+1 h[ev] little1 ! bord]s to :i* natural ov]fl[ _h c>ri$ x4 ,any attempt to make t scanty surplus1 by means ( ov]fl[+ canals1 travel across ! equator into ! opposite hemisph]e1 ?r\gh su* a t]rible des]t region & expos$ to su* a cl\dless sky z ,mr4 ,l[ell describes1 w\ld be ! "w ( a body ( madm5 r ?an ( intellig5t be+s4 ,x may be safely ass]t$ t n "o drop ( wat] w\ld escape evaporation or insoak at ev5 a hundr$ miles f its s\rce4 #e ,footnote #e3 ,:at ! evaporation is likely to be 9 ,m>s may be e/imat$ by ! fact1 /at$ by ,pr(essor ,j4,w4 ,gregory 9 8 rec5t volume on ',au/ralia' 9 ,/an=d's ,comp5dium1 t 9 ,nor?-,we/ ,victoria evaporation is at ! rate ( t5 feet p] annum1 :ile 9 ,c5tral ,au/ralia x is v mu* m4 ,! greatly dim9i%$ atmosph]ic pressure 9 ,m>s w probably m ?an balance ! loss ( sun-heat 9 produc+ rapid evaporation4 ,miss ,cl]ke on ! ,scanty ,wat]-supply4 ,on ?is po9t ,i am support$ by no less an au?ority ?an ! hi/orian ( mod]n a/ronomy1 ! late ,miss ,agnes ,cl]ke4 ,9 ! ,ed9burgh ,review 7( ,octob] #ahif7 !re is an article entitl$ ',new ,views ab\t ,m>s1' exhibit+ ! writ]'s *>act]i/ic fulness ( k & *>m ( /yle4 ,speak+ ( ,mr4 ,l[ell's idea ( ! 'canals' c>ry+ ! surplus wat] across ! equator1 f> into ! opposite hemisph]e1 = purposes ( irrigation !re 7:i* we see he aga9 /ates 9 ! pres5t volume71 ,miss ,cl]ke writes3 ,we c h>dly imag9e s %rewd a p z ! irrigators ( ,?ule & ,hellas#f wa/+ lab\r1 & ! life-giv+ fluid1 aft] s unpr(itable a fa%ion4 ,!re is e reason to believe t ! ,m>tian sn[-caps are q flimsy /ructures4 ,_! mat]ial might be call$ sn[ s\ffl1 s9ce1 ow+ to ! small p[] ( gravity on ,m>s1 sn[ is almo/ ?ree times light] !re ?an "h4 ,consequ5tly1 its own weight c h v little effect 9 r5d]+ x compact4 ,nor1 inde$1 is !re "t = mu* settl+ d[n4 ,! calotte does n =m until sev]al mon?s aft] ! w9t] sol/ice1 & x beg9s to melt1 z a rule1 %ortly aft] ! v]nal equ9ox4 7,! int]val betwe5 ^! two epo*s 9 ! s\!rn hemisph]e ( ,m>s is #agf days47 ,! sn[ lies on ! gr\nd1 at ! outside1 a c\ple ( mon?s4 ,at times x melts :ile x is /ill fre% fall54 ,?us1 at ! opposition ( #ahha-hb ! spread+ ( ! nor!rn sn[s 0 delay$ until sev5 weeks aft] ! equ9ox3 & !y _h1 accord+ly1 no soon] rea*$ _! maximum ?an !y began to decl9e4 ,& ,pr(essor ,pick]+'s photographs ( ,april #i? & #aj?1 #ahij1 prov$ t ! s\!rn calotte may assume its def9itive proportions 9 a s+le night4 ,footnote #f3 ,areas on ,m>s s nam$4 ,no attempt has yet be5 made to e/imate ! quantity ( wat] d]ivable f ! melt+ ( "o ( ^! =mations2 yet ! exp]im5t is wor? try+ z a help t[>ds def9+ ideas4 ,let u grant t ! av]age dep? ( sn[ 9 !m1 ( ! delicate ,m>tian k9d1 is tw5ty feet1 equival5t at ! mo/ to "o foot ( wat]4 ,! maximum area cov]$1 ( #b1djj1jjj squ>e miles1 is ne>ly equal to t ( ! ,unit$ ,/ates1 :ile ! :ole globe ( ,m>s measures #ee1ejj1jjj squ>e miles1 ( :i* "o-?ird1 on ! pres5t hypo!sis1 is "u cultivation1 & 9 ne$ ( wat]4 ,ne>ly ! :ole ( ! d>k areas1 z we "k1 are situat$ 9 ! s\!rn hemisph]e1 ( :i* !y ext5d ov]1 at ! v lea/1 #ag1jjj1jjj squ>e miles2 t is to say1 !y cov] an area1 9 r\nd numb]s1 sev5 times t ( ! sn[-cap4 ,only "o-sev5? ( a foot ( wat]1 accord+ly1 c\ld possibly be made available = _! f]tilisation1 suppos+ !m to get ! entire advantage ( ! spr+ fre%et4 ,^u a /9t ( less ?an two in*es ( wat] ^! f]tile l&s are expect$ to fl\ri% & be> abundant crops2 & s9ce !y completely enclose ! pol> area !y are necess>ily s]v$ fir/4 ,! great emiss>ies = c>ry+ (f ! surplus ( _! aque\s ri*es1 w\ld !n appe> to be sup]flu\s con/ructions1 nor is x likely t ! %>e 9 ^? ri*es due to ! canals & oases1 intricately divid+ up ! wide1 dry1 cont95tal pla9s1 c ev] be realis$4 ,we h assum$1 9 our little calculation1 t ! entire cont5ts ( a pol> hood turn to wat]2 b 9 actual fact a consid]able proportion ( !m mu/ pass directly into vap\r1 omitt+ ! int]m$iate /age4 ,ev5 ) u a l>ge quantity ( sn[ is remov$ a]ially2 & 9 ! r>e atmosph]e ( ,m>s ?is cause ( wa/e mu/ be especially effective4 ,?us ! pol> res]voirs are despoil$ 9 ! act ( be+ op5$4 ,fur!r objections might be tak5 to ,mr4 ,l[ell's irrigation s*eme1 b en\gh has be5 said to %[ t x is hopelessly unworkable4 ,x w be se5 t ! writ] ( ?is article accept$ ! exi/5ce ( wat] on ,m>s1 on ! te/imony ( ,sir ,w4 ,hugg9s1 :i*1 9 view ( lat] obs]vations1 he has himself ackn[l$g$ to be valueless4 ,dr4 ,john/one ,/oney's pro( ( its abs5ce1 d]iv$ f ! molecul> !ory ( gases1 _h n !n be5 made public4 ,description ( "s ( ! ,canals4 ,at ! end ( 8 volume ,mr4 ,l[ell gives a l>ge *>t ( ,m>s on ,m]cator's projection1 %[+ ! canals & o!r features se5 dur+ ! opposition ( #aije4 ,?is conta9s _m canals n %[n on ! map "h reproduc$ 7see frontispiece71 & "s ( ! diff]5ces betwe5 ! two are v puzzl+4 ,look+ at our map1 :i* %[s ! nor?-pol> sn[ bel[1 s t ! s\? pole is out ( ! view at ! top ( ! map1 ! c5tral feature is ! l>ge spot ,ascraeeus ,lucus1 f :i* t5 canals div]ge c5trally1 & f\r f ! sides1 =m+ wide d\ble canals1 f\rte5 9 all4 ,!re is also a canal nam$ ,ulysses1 :i* "h passes f> to ! "r ( ! spot1 b 9 ! l>ge *>t ent]s x c5trally4 ,look+ at our map we see1 go+ d[nw>ds a little to ! left1 ! canal ,udon1 :i* runs ?r\gh a d>k area q to ! out] m>g94 ,9 ! d>k area1 h[ev]1 !re is %[n on ! *>t a spot ,aspl$on ,lucus1 :]e five canals meet1 & if ?is is tak5 z a t]m9us ! ,udon canal is almo/ exactly #bjjj miles long1 & ano!r on its "r1 ,lapadon1 is ! same l5g?1 :ile ,i*1 runn+ 9 a slightly curv$ l9e to a l>ge spot 7,lucus ,ca/orius on ! *>t7 is /ill long]4 ,! ,ulysses canal1 :i* 7on ! *>t7 runs /raight f ! po9t ( ! ,m>e ,sir5um to ! ,a/raeeus ,lucus is ab\t #bbjj miles long4 ,o!rs h[ev] are ev5 long]1 & ,mr4 ,l[ell says3 ,) !m #bjjj miles is common2 :ile _m exce$ #bejj2 & ! ,eum5ides-,orcus is #cedj miles f ! po9t :]e x leaves ,lucus ,pho5iceus to :]e x ent]s ! ,trivium ,*>ontis4 ,?is la/ canal is b>ely visible on our map1 its comm5cem5t be+ indicat$ by ! ^w ,eum5ides4 ,! ,trivium ,*>ontis is situat$ j beyond ! "r-h& m>g9 ( our map4 ,x is a triangul> d>k area1 ! sides ab\t #bjj miles long1 & x is %[n on ! *>t z be+ ! c5tre f :i* radiate ?irte5 canals4 ,ano!r c5tre is ,aquae ,calidae situat$ at ! po9t ( a d>k area runn+ obliquely f #ee to #ce ,n4 latitude1 &1 z %[n on a map ( ! opposite hemisph]e to our map1 has ne>ly tw5ty canals radiat+ f x 9 almo/ e direction4 ,"h at all ev5ts !re seems to be no special connection ) ! pol> sn[-caps1 & ! radiat+ l9es seem to h no intellig5t purpose :atev]1 b are su* z might result f fractures 9 a glass globe produc$ by fir+ at x ) v small %ots "o at a "t4 ,tak+ ! :ole s]ies ( !m1 ,mr4 ,l[ell v ju/ly comp>es !m to a network :i* triangulates ! surface ( ! planet l a geodetic survey1 into polygons ( all %apes & sizes4 ,at ! v l[e/ e/imate ! total l5g? ( ! canals obs]v$ & mapp$ by ,mr4 ,l[ell mu/ be ov] a hundr$ ?\s& miles1 :ile he assures u t numb]s ( o!rs h be5 se5 ov] ! :ole surface1 b s fa9tly or on su* r>e occasions z to elude all attempts to fix _! position ) c]ta9ty4 ,b ^!1 be+ ( ! same "* & evid5tly =m+ "p ( ! same sy/em1 mu/ also be artificial1 & ?us we are l$ to a sy/em ( irrigation ( almo/ unimag9able magnitude on a planet :i* has no m\nta9s1 no riv]s1 & no ra9 to support x2 ^: :ole wat]-supply is d]iv$ f pol> sn[s1 ! am\nt ( :i* is ludicr\sly inadequate to ne$ any su* _w-wide sy/em2 :ile ! l[ atmosph]ic pressure w\ld lead to rapid evaporation1 ?us greatly dim9i%+ ! small am\nt ( moi/ure t is available4 ,ev]yone mu/1 ,i ?9k1 agree ) ,miss ,cl]ke1 t1 ev5 admitt+ ! assumption t ! pol> sn[s consi/ ( froz5 wat]1 ! excessively scanty am\nt ( wat] ?us obta9$ w\ld r5d] any s*eme ( _w-wide di/ribution ( x hopelessly unworkable4 ,! v rem>kable ph5om5a ( ! duplication ( _m ( ! l9es1 toge!r ) ! d>kspots--! s-call$ oases--at _! int]sections1 are d\btless all connect$ 9 "s unkn[n way ) ! con/itution & pa/ hi/ory ( ! planet2 b1 on ! !ory ( ! :ole be+ works ( art1 !y c]ta9ly d n help to remove any ( ! difficulties :i* h be5 %[n to att5d ! !ory t ! s+le l9es repres5t artificial canals ( irrigation ) a /rip ( v]dure on ea* side ( !m produc$ by _! ov]fl[4 ,l[ell on ! ,purpose ( ! ,canals4 ,be=e leav+ ?is subject x w be well to quote ,mr4 ,l[ell's own words z to ! suppos$ p]fectly level surface ( ,m>s1 & 8 int]pretation ( ! orig9 & purpose ( ! 'canals'3 ,a body ( planet>y size1 if unrotat+1 becomes a sph]e1 except = sol> tidal de=mation2 if rotat+1 x takes on a sph]oidal =m exactly expressive1 s f> z obs]vation goes1 ( ! s-call$ c5trifugal =ce at "w4 ,m>s pres5ts su* a figure1 be+ flatt5$ out to correspond to its axial rotation4 ,its surface !re=e is 9 fluid equilibrium1 or1 9 o!r words1 a p>ticle ( liquid at any po9t ( its surface at ! pres5t "t w\ld /ay :]e x 0 devoid ( incl9ation to move else:]e4 ,n[ ! wat] :i* quick5s ! v]dure ( ! canals moves f ! pole d[n to ! equator z ! season advances4 ,?is x does !n irrespective ( gravity4 ,no natural =ce propels x1 & ! inf]5ce is =?right & inevitable t x is artificially help$ to its end4 ,!re seems to be no escape f ?is d$uction4 ,wat] only fl[s d[nhill1 & !re is no su* ?+ z d[nhill on a surface already 9 fluid equilibrium4 ,a few canals might presumably be s situat$ t _! fl[ c\ld1 by inequality ( t]rane1 lie equatorw>d1 b n all4444,n[ x is n 9 p>ticul> b by g5]al cons5t t ! canal-sy/em ( ,m>s develops f pole to equator4 ,f ! respective times at :i* ! m9ima take place1 x appe>s t ! canal quick5+ occupies fifty-two days1 z evid5c$ by ! successive vegetal d>k5+s1 to desc5d f latitude #gb nor? to latitude #j1 a j\rney ( #bfej miles4 ,?is gives = ! wat] a spe$ ( fifty-"o miles a day1 or #b4a miles an h\r4 ,! rate ( progression is rem>kably uni=m1 & ?is abets ! d$uction z to assi/$ transf]5ce4 ,b ! fact is m unnatural yet4 ,! gr[? pays no reg>d to ! equator1 b proce$s across x z if x did n exi/ into ! planet's o!r hemisph]e4 ,"h is some?+ /ill m tell+ ?an travel to ?is po9t4 ,= ev5 if we suppose1 = ! sake ( argum5t1 t natural =ces took ! wat] d[n to ! equator1 _! action mu/ !re be c]ta9ly rev]s$1 & ! equator prove a dead-l9e1 to pass :i* 7 impossible 7pp4 #cgd-e74 ,i ?9k my read]s w agree ) me t ?is :ole argum5t is "o ( ! mo/ curi\s ev] put =? s]i\sly by an em95t man ( sci5ce4 ,because ! pol> compression ( ,m>s is ab\t :at calculation %[s x ought to be 9 accordance ) its rate ( rotation1 its surface is 9 a /ate ( 'fluid equilibrium1' & mu/ !re=e be absolutely level ?r\gh\t4 ,b ! pol> compression ( ! e>? equally agrees ) calculation2 !re=e its surface is also 9 'fluid equilibrium'2 !re=e x also ought to be z p]fectly level on l& z x is on ! ocean surface6 ,b z we "k ?is is v f> f be+ ! case1 :y mu/ x be s 9 ,m>s8 ,are we to suppose ,m>s to h be5 =m$ 9 "s totally diff]5t way f o!r planets1 & t !re nei!r is nor ev] has be5 any reaction betwe5 its int]ior & ext]ior =ces8 ,aga91 ! assumption ( p]fect flatness is directly oppos$ to all obs]vation & all analogy ) :at we see on ! e>? & moon4 ,x gives no acc\nt :atev] ( ! num]\s & l>ge d>k pat*es1 once t]m$ seas1 b n[ f\nd to be n s1 & to be full ( detail$ m>k+s & v>i$ dep?s ( %ad[4 ,to suppose t ^! are all ! same dead-level z ! light-col\r$ portions are assum$ to be1 implies t ! d>kness is "o ( mat]ial & col\r only1 n ( div]sifi$ cont\r1 :i* aga9 is contr>y to exp]i5ce1 s9ce diff]5ce ( mat]ial ) u always leads to diff]5ces 9 rate ( degradation1 & h5ce ( div]sifi$ cont\r1 z ^! d>k spaces actually %[ !mselves "u fav\rable conditions to indep5d5t obs]v]s4 ,l[ell on ! ,sy/em ( ,canals z a :ole4 ,we w n[ see :at ,mr4 ,l[ell claims to be ! pla9 tea*+ ( ! 'canals' z a :ole3 ,b la/ & all-embrac+ 9 its import is ! sy/em :i* ! canals =m4 ,in/ead ( runn+ at hap-haz>d1 ! canals are int]connect$ 9 a mo/ rem>kable mann]4 ,!y seek c5tres in/ead ( avoid+ !m4 ,! c5tres are l9k$ ?us p]fectly "o ) ano!r1 an arrangem5t :i* c\ld n result f c5tres1 :e!r ( explosion or o!rwise1 :i* 7 !mselves discrete4 ,fur!rmore1 ! sy/em cov]s ! :ole surface ( ! planet1 d>k areas & light ones alike1 a _w-wide di/ribution :i* exce$s ! b\nds ( natural possibility4 ,any =ce :i* c\ld act longitud9ally on su* a scale mu/ be limit$ latitud9ally 9 its action1 z witness ! belts ( ,jupit] & ! spots ^u ! sun4 ,rotational1 climatic1 or o!r physical cause c\ld n fail ( zonal expression4 ,yet ^! l9es are gr&ly indiff]5t to su* compet+ influ5ces4 ,f9ally1 ! sy/em1 aft] me%+ ! surface 9 its entirety1 runs /raight into ! pol> caps4 ,x is1 !n1 a sy/em ^: end & aim is ! tapp+ ( ! sn[-cap = ! wat] !re semi-annually let loose2 !n to di/ribute x ov] ! planet's face 7p4 #cgc74 ,"h1 aga91 we h curi\sly weak argum5ts adduc$ to support ! view t ^! num]\s /raight l9es imply works ( art r ?an ( nature1 especially 9 ! comp>ison made ) ! belts ( ,jupit] & ! spots on ! sun1 bo? purely atmosph]ic ph5om5a1 :]eas ! l9es on ,m>s are on ! solid surface ( ! planet4 ,:y %\ld !re be any resemblance betwe5 !m8 ,e fact /at$ 9 ! above quotation1 always keep+ 9 m9d ! physical conditions ( ! planet--its v t5u\s atmosph]e & ra9less des]t-surface--seem :olly 9 fav\r ( a purely natural z oppos$ to an artificial orig92 & at ! close ( ?is discussion ,i %all sugge/ "o :i* seems to me to be at lea/ possible1 & to expla9 ! :ole s]ies ( ! ph5om5a set =? & l>gely discov]$ by ,mr4 ,l[ell1 9 a simpl] & m probable mann] ?an does 8 trem5d\s assumption ( _! be+ works ( art4 ,read]s :o may n possess ,mr4 ,l[ell's volume w f9d ?ree ( 8 mo/ rec5t maps ( ! 'canals' reproduc$ 9 ,nature ( ,octob] #aa?1 #aijf4 ,,*apt] ,,iv4 ,,is ,,animal ,,life ,,possible ,,on ,,m>s8 ,hav+ n[ %[n1 t1 ev5 admitt+ ! accuracy ( all ,mr4 ,l[ell's obs]vations1 & provisionally accept+ all 8 *ief conclusions z to ! climate1 ! nature ( ! sn[-caps1 ! vegetation1 & ! animal life ( ,m>s1 yet 8 int]pretation ( ! l9es on its surface z be+ v]itably 'canals1' con/ruct$ by intellig5t be+s = ! special purpose ( c>ry+ wat] to ! m arid regions1 is :olly errone\s & rationally inconceivable4 ,i n[ proce$ to discuss 8 m fundam5tal position z to ! actual habitability ( ,m>s by a highly organis$ & intellectual race ( mat]ial organic be+s4 ,wat] & ,air ess5tial to ,life4 ,"h1 =tunately1 ! issue is r5d]$ v simple1 because ,mr4 ,l[ell fully recognises ! id5tity ( ! con/itution ( matt] & ( physical laws ?r\gh\t ! sol>-sy/em1 & t = any high =m ( organic life c]ta9 conditions :i* are absolutely ess5tial on our e>? mu/ also exi/ 9 ,m>s4 ,he admits1 = example1 t wat] is ess5tial1 t an atmosph]e conta9+ oxyg51 nitrog51 aque\s vap\r1 & c>bonic acid gas is ess5tial1 & t an abundant vegetation is ess5tial2 & ^! ( c\rse involve a surface-temp]ature ?r\gh a consid]able portion ( ! ye> t r5d]s ! exi/5ce ( ^!--especially ( wat]--possible & available = ! purposes ( a high & abundant animal life4 ,blue ,col\r ! only ,evid5ce ( ,wat]4 ,9 attempt+ to %[ t ^! ess5tials actually exi/ on ,m>s he is n v successful4 ,he adduces evid5ce ( an atmosph]e1 b ( an exce$+ly scanty "o1 s9ce ! greate/ am\nt he c give to x is-- n m ?an ab\t f\r in*es ( b>ometric pressure z we reckon x2#g & he assumes1 z he has a fair "r to d till disprov$1 t x consi/s ( oxyg5 & nitrog51 ) c>bon-dioxide & wat]-vap\r1 9 approximately ! same proportions z ) u4 ,) reg>d to ! la/ item--! wat]-vap\r--!re are h[ev] _m s]i\s difficulties4 ,! wat]-vap\r ( our atmosph]e is d]iv$ f ! enorm\s area ( our seas1 oceans1 lakes1 & riv]s1 z well z f ! evaporation f heat$ l&s & tropical =e/s ( mu* ( ! moi/ure produc$ by frequ5t & abundant ra9s4 ,all ^! s\rces ( supply are admitt$ly abs5t f ,m>s1 :i* has no p]man5t bodies ( wat]1 no ra91 & tropical regions :i* are almo/ entirely des]t4 ,_m writ]s h !re=e d\bt$ ! exi/5ce ( wat] 9 any =m ^u ?is planet1 suppos+ t ! sn[-caps are n =m$ ( froz5 wat] b ( c>bon-dioxide1 or "s o!r heavy gas1 9 a froz5 /ate2 & ,mr4 ,l[ell evid5tly feels ?is to be a difficulty1 s9ce ! only fact he is able to adduce 9 fav\r ( ! melt+ sn[s ( ! pol> caps produc+ wat] is1 t at ! "t !y are melt+ a m>g9al blue b& appe>s :i* accompanies !m 9 _! retreat1 & ?is blue col\r is said to prove conclusively t ! liquid is n c>bonic acid b wat]4 ,?is po9t he dwells ^u repeat$ly1 /at+1 ( ^! blue bord]s3 ,?is excludes ! possibility ( _! be+ =m$ by c>bon-dioxide1 & %[s t ( all ! sub/ances we "k ! mat]ial compos+ !m mu/ be wat]4 ,footnote #g3 ,9 a pap] writt5 s9ce ! book appe>$ ! d5sity ( air at ! surface ( ,m>s is said to be #a_/ab ( ! e>?'s4 ,?is is ! only pro( ( ! exi/5ce ( wat] he adduces1 & x is c]ta9ly a mo/ extraord9>y & futile "o4 ,= x is p]fectly well kn[n t al?\gh wat]1 9 l>ge masses & by transmitt$ light1 is ( a blue col\r1 yet %all[ wat] by reflect$ light is n s2 & 9 ! case ( ! liquid produc$ by ! sn[-caps ( ,m>s1 :i* ! :ole conditions ( ! planet %[ mu/ be %all[1 & also be m or less turbid1 x _c possibly be ! cause ( ! 'deep blue' t9t said to result f ! melt+ ( ! sn[4 ,b !re is a v weighty argum5t dep5d+ on ! molecul> !ory ( gases aga9/ ! pol> caps ( ,m>s be+ compos$ ( froz5 wat] at all4 ,! mass & ela/ic =ce ( ! sev]al gases is due to ! great] or less rapidity ( ! vibratory motion ( _! molecules "u id5tical conditions4 ,! spe$ ( ^! molecul> motions has be5 asc]ta9$ = all ! *ief gases1 & x is f\nd to be s great z 9 c]ta9 cases to enable !m to ov]come ! =ce ( gravity & escape f a planet's surface into space4 ,dr4 ,g4 ,john/one ,/oney has specially inve/igat$ ?is subject1 & he f9ds t ! =ce ( gravity on ! e>? is suffici5t to reta9 all ! gases compos+ its atmosph]e1 b n suffici5t to reta9 hydrog52 & z a consequ5ce1 al?\gh ?is gas is produc$ 9 small quantities by volcanoes & by decompos+ vegetation1 yet no trace ( x is f\nd 9 our atmosph]e4 ,! moon h[ev]1 hav+ only "o-eightie? ! mass ( ! e>?1 _c reta9 any gas1 h5ce its airless & wat]less condition4 ,wat] ,vap\r _c exi/ on ,m>s4 ,n[1 ,dr4 ,/oney f9ds t 9 ord] to reta9 wat] vap\r p]man5tly a planet mu/ h a mass at lea/ a qu>t] t ( ! e>?4 ,b ! mass ( ,m>s is only "o-n9? t ( ! e>?2 !re=e1 unless !re are "s special conditions t prev5t its loss1 ?is gas _c be pres5t 9 ! atmosph]e4 ,mr4 ,l[ell does n ref] to ?is argum5t aga9/ 8 view1 nei!r does he claim ! evid5ce ( spectroscopy 9 8 fav\r4 ,?is 0 alleg$ m ?an ?irty ye>s ago to %[ ! exi/5ce ( wat]-vap\r 9 ! atmosph]e ( ,m>s1 b ( late ye>s x has be5 d\bt$1 & ,mr4 ,l[ell's complete sil5ce on ! subject1 :ile lay+ /ress on su* a v weak & inconclusive argum5t z t f ! t+e ( col\r t is obs]v$ a little di/ance f ! edge ( ! dim9i%+ sn[-caps1 %[s t he himself does n ?9k ! fact to be ?us prov$4 ,if he did he w\ld h>dly adduce su* an argum5t = its pres5ce z ! foll[+3 ,! melt+ ( ! caps on ! "o h& & _! re-=m+ on ! o!r affirm ! pres5ce ( wat]-vap\r 9 ! ,m>tian atmosph]e1 ( :atev] else t air consi/s 7p4 #afb74 ,yet absolutely ! only pro( he gives t ! caps are froz5 wat] is ! almo/ frivol\s col\r-argum5t above ref]r$ to6 ,no ,spectroscopic ,evid5ce ( ,wat] ,vap\r4 ,z ,sir ,william ,hugg9s is ! *ief au?ority quot$ = ?is fact1 & is ref]r$ to z be+ almo/ conclusive 9 ! ?ird edition ( ,miss ,cl]ke's ,hi/ory ( ,a/ronomy 9 #ahic1 ,i h asc]ta9$ t 8 op9ion at ! pres5t "t is t !re is no conclusive pro( ( ! pres5ce ( aque\s vap\r 9 ! atmosph]e ( ,m>s1 & t obs]vations at ! ,lick ,obs]vatory 79 #ahie71 :]e ! conditions & in/rum5ts are ( ! highe/ ord]1 7 negative4 ,he also in=ms me t ,m>*& at ! ,pic du ,midi ,obs]vatory 0 unable to obta9 l9es ( aque\s vap\r 9 ! spectrum ( ,m>s2 & t 9 #aije1 ,sliph]1 at ,mr4 ,l[ell's obs]vatory1 0 unable to detect any indications ( aque\s vap\r 9 ! spectrum ( ,m>s4 ,x ?us appe>s t spectroscopic obs]vations are q accordant ) ! calculations f\nd$ on ! molecul> !ory ( gases z to ! abs5ce ( aque\s vap\r1 & !re=e presumably ( liquid wat]1 f ,m>s4 ,x is true t ! spectroscopic argum5t is purely negative1 & ?is may be due to ! extreme delicacy ( ! obs]vations requir$2 b t dep5d5t on ! inability ( ! =ce ( gravity to reta9 x is positive sci5tific evid5ce aga9/ its pres5ce1 &1 till %[n to be errone\s1 mu/ be held to be conclusive4 ,?is abs5ce ( wat] is ( itself conclusive aga9/ ! exi/5ce ( animal life1 unless we ent] ! regions ( pure conjecture z to ! possibility ( "s o!r liquid be+ able to take its place1 & t liquid be+ z omnipres5t !re z wat] is "h4 ,mr4 ,l[ell h[ev] nev] takes ?is gr\nd1 b bases 8 :ole !ory on ! fundam5tal id5tity ( ! sub/ance ( ! bodies ( liv+ organisms :]ev] !y may exi/ 9 ! sol> sy/em4 ,9 ! next two *apt]s ,i %all discuss an equally ess5tial condition1 t ( temp]ature1 :i* af=ds a /ill m conclusive & ev5 cru%+ argum5t aga9/ ! suitability ( ,m>s = ! exi/5ce ( organic life4 ,,*apt] ,v4 ,,! ,,temp]ature ,,( ,,m>s--,,mr4 ,,l[ell',s ,,e/imate4 ,we h n[ to consid] a /ill m important & fundam5tal "q1 & "o :i* ,mr4 ,l[ell does n grapple ) 9 ?is volume1 ! actual temp]atures on ,m>s due to its di/ance f ! sun & ! atmosph]ic conditions on :i* he himself lays s mu* /ress4 ,if ,i am n greatly mi/ak5 we %all arrive at conclusions on ?is subject :i* are absolutely fatal to ! conception ( any high =m ( organic life be+ possible on ?is planet4 ,! ,problem ( ,t]re/rial ,temp]atures4 ,9 ord] t ! problem may be und]/ood & its importance appreciat$1 x is necess>y to expla9 ! n[ g5]ally accept$ pr9ciples z to ! causes :i* det]m9e ! temp]atures on our e>?1 &1 presumably1 on all o!r planets ^: conditions are n :olly unlike ours4 ,! fact ( ! int]nal heat ( ! e>? :i* becomes v p]ceptible ev5 at ! mod]ate dep?s rea*$ 9 m9es & deep bor+s1 & 9 ! deepe/ m9es becomes a positive inconv5i5ce1 leads _m p to suppose t ! surface- temp]atures ( ! e>? are p>tly due to ?is cause4 ,b x is n[ g5]ally admitt$ t ?is is n ! case1 ! reason be+ t all rocks & soils1 9 _! natural compact$ /ate1 are exce$+ly bad conductors ( heat4 ,a /rik+ illu/ration ( ?is is ! fact1 t a /ream ( lava (t5 cont9ues to be r$ hot at a few feet dep? = ye>s aft] ! surface is consolidat$1 & is h>dly any w>m] ?an t ( ! surr\nd+ l&4 ,a /ill m rem>kable case is t ( a glaci] on ! s\?-ea/ side ( ! highe/ cone ( ,etna und]nea? a lava /ream ) an int]v5+ b$ ( volcanic s& only t5 feet ?ick4 ,?is 0 visit$ by ,sir ,*>les ,lyell 9 #ahbh1 & a second "t ?irty ye>s lat]1 :5 he made a v c>eful exam9ation ( ! /rata1 & 0 q satisfi$ t ! s& & ! lava /ream toge!r _h actually pres]v$ ?is mass ( ice1 :i* nei!r ! heat ( ! lava above x at its fir/ outfl[1 nor ! cont9u$ heat ris+ f ! great volcano bel[ x1 _h be5 able to melt or p]ceptibly to dim9i% 9 ?irty ye>s4 ,ano!r fact t po9ts 9 ! same direction is ! exi/5ce ov] ! :ole floor ( ! deepe/ oceans ( ice-cold wat]1 :i*1 orig9at+ 9 ! pol> seas1 ow+ to its great] d5sity s9ks & creeps sl[ly along ! ocean bottom to ! dep?s ( ! ,atlantic & ,pacific1 & is n p]ceptibly w>m$ by ! int]nal heat ( ! e>?4 ,n[ ! solid cru/ ( ! e>? is e/imat$ z at lea/ ab\t tw5ty miles 9 av]age ?ickness2 &1 keep+ 9 m9d ! o!r facts j ref]r$ to1 we c und]/& t ! heat f ! int]ior passes ?r\gh x ) su* extreme sl[ness z n to be detect$ at ! surface1 ! v>y+ temp]atures ( :i* are due entirely to sol> heat4 ,a l>ge portion ( ?is heat is /or$ up 9 ! surface soil1 & especially 9 ! surface lay] ( ! oceans & seas1 ?us p>tly equalis+ ! temp]atures ( day & night1 ( w9t] & summ]1 s z greatly to ameliorate ! rapid *anges ( temp]ature t w\ld o!rwise occur4 ,our d5se atmosph]e is also ( imm5se advantage to u z an equalis] ( temp]ature1 *>g$ z x almo/ always is ) a l>ge quantity ( wat]-vap\r4 ,?is latt] gas1 :5 n cond5s$ into cl\d1 all[s ! sol> heat to pass freely to ! e>?2 b x has ! s+ul> & highly b5eficial prop]ty ( absorb+ & reta9+ ! d>k or l[]-grade heat giv5 (f by ! e>? :i* w\ld o!rwise radiate into space mu* m rapidly4 ,we mu/ !re=e always rememb] t1 v ne>ly if n q1 ! :ole ( ! w>m? we exp]i5ce on ! e>? is d]iv$ f ! sun4#h ,footnote #h3 ,pr(essor ,j4,h4 ,poynt+1 9 8 lecture to ! ,briti% ,association at ,cambridge 9 #aijd1 says3 ,! surface ( ! e>? receives1 we "k1 an am\nt ( heat f ! inside almo/ inf9itesimal comp>$ ) t :i* x receives f ! sun1 & on ! sun1 !re=e1 we dep5d = our temp]ature4 ,9 ord] to und]/& ! imm5se significance ( ?is conclusion we mu/ "k :at is meant by ! :ole heat or w>m?2 z unless we "k ?is we _c def9e :at half or any o!r proportion ( sun-heat really means4 ,n[ ,i feel pretty sure t n9e out ( t5 ( ! av]age educat$ public w\ld answ] ! foll[+ "q incorrectly3 ,! mean temp]ature ( ! s\!rn half ( ,engl& is ab\t #dh ,f4 ,suppos+ ! e>? receiv$ only half ! sun-heat x n[ receives1 :at w\ld !n be ! probable mean temp]ature ( ! ,s\? ( ,engl&8 ,! majority w\ld1 ,i ?9k1 answ] at once--,ab\t #bd ,f4 ,ne>ly z _m w\ld p]haps say--#dh ,f4 is #af above ! freez+ po9t2 !re=e half ! heat receiv$ w\ld br+ u d[n to #h above ! freez+ po9t1 or #dj ,f4 ,v few1 ,i ?9k1 w\ld realise t our %>e ( half ! am\nt ( sun-heat receiv$ by ! e>? w\ld probably result 9 r$uc+ our mean temp]ature to ab\t #ajj ,f4 bel[ ! freez+ po9t1 & p]haps ev5 l[]4 ,?is is ab\t ! v l[e/ temp]ature yet exp]i5c$ on ! e>?'s surface4 ,to und]/& h[ su* results are obta9$ a few words mu/ be said ab\t ! absolute z]o ( temp]ature4 ,! ,z]o ( ,temp]ature4 ,heat is n[ believ$ to be entirely due to e!r-vibration1 :i* produces a correspond+ly rapid vibration ( ! molecules ( matt]1 caus+ x to exp& & produc+ all ! ph5om5a we t]m 'heat4' ,we c conceive ?is vibration to increase indef9itely1 & ?us !re w\ld appe> to be no necess>y limit to ! am\nt ( heat possible1 b we _c conceive x to decrease indef9itely at ! same uni=m rate1 z x mu/ soon inevitably come to no?+4 ,n[ x has be5 f\nd by exp]im5t t gases "u uni=m pressure exp& #a_/bgc ( _! volume = ea* degree ,c5tigrade ( increas$ temp]ature1 s t 9 pass+ f #j ,c4 to #bgc ,c4 !y are d\bl$ 9 volume4 ,!y also decrease 9 volume at ! same rate = ea* degree bel[ #j ,c4 7! freez+ po9t ( wat]74 ,h5ce if ?is goes on to-#bgc ,c4 a gas w h no volume1 or x w und]go "s *ange ( nature4 ,h5ce ?is is call$ ! z]o ( temp]ature1 or ! temp]ature to :i* any matt] falls :i* receives no heat f any o!r matt]4 ,x is also sometimes call$ ! temp]ature ( space1 or ( ! e!r 9 a /ate ( re/1 if t is possible4 ,all ! gases h n[ be5 prov$ to become1 fir/ liquid & !n 7mo/ ( !m7 solid1 at temp]atures consid]ably above ?is z]o4 ,! only way to comp>e ! proportional temp]atures ( bodies1 :e!r on ! e>? or 9 space1 is !re=e by means ( a scale beg9n+ at ?is natural z]o1 in/ead ( ^? scales f\nd$ on ! artificial z]o ( ! freez+ po9t ( wat]1 or1 z 9 ,fahr5heit's1 #cb bel[ x4 ,only by us+ ! natural z]o & measur+ cont9u\sly f x c we e/imate temp]atures 9 relative proportion to ! am\nt ( heat receiv$4 ,?is is t]m$ ! absolute z]o1 & s t we />t reckon+ f t po9t x does n matt] :e!r ! scale adopt$ is ! ,c5tigrade or t ( ,fahr5heit4 ,! ,complex ,problem ( ,planet>y ,temp]atures4 ,n[ if1 z is ! case ) ,m>s1 a planet receives only half ! am\nt ( sol> heat t we receive1 ow+ to its great] di/ance f ! sun1 & if ! mean temp]ature ( our e>? is #fj ,f41 ?is is equal to #eea ,f4 on ! absolute scale4 ,x w\ld !re=e appe> v simple to halve ?is am\nt & obta9 #bge4e ,f4 z ! mean temp]ature ( t planet4 ,b ?is result is errone\s1 because ! actual am\nt ( sun heat int]cept$ by a planet is only "o condition out ( _m t det]m9e its result+ temp]ature4 ,radiation1 t is loss ( heat1 is go+ on concurr5tly ) ga91 & ! rate ( loss v>ies ) ! temp]ature accord+ to a law rec5tly discov]$1 ! loss be+ mu* great] at high temp]atures 9 proportion to ! #d? p[] ( ! absolute temp]ature4 ,!n1 aga91 ! :ole heat int]cept$ by a planet does n rea* its surface unless x has no atmosph]e4 ,:5 x has "o1 mu* is reflect$ or absorb$ accord+ to complex laws dep5d5t on ! d5sity & composition ( ! atmosph]e4 ,!n1 aga91 ! heat t rea*es ! actual surface is p>tly reflect$ & p>tly absorb$1 accord+ to ! nature ( t surface--l& or wat]1 des]t or =e/ or sn[-clad--t "p :i* is absorb$ be+ ! *ief ag5t 9 rais+ ! temp]ature ( ! surface & ( ! air 9 contact ) x4 ,v important too is ! loss ( heat by radiation f ^! v>i\s heat$ surfaces at diff]5t rates2 :ile ! atmosph]e itself s5ds back to ! surface an ev] v>y+ portion ( bo? ?is radiant & reflect$ heat accord+ to di/9ct laws4 ,fur!r difficulties arise f ! fact t mu* ( ! sun's heat consi/s ( d>k or invisible rays1 & x _c !re=e be measur$ by ! quantity ( light only4 ,f ?is r\gh /atem5t x w be se5 t ! problem is an exce$+ly complex "o1 n to be decid$ (f-h&1 or by any simple me?od4 ,x has 9 fact be5 usually consid]$ z 7/rictly speak+7 insoluble1 & only to be e/imat$ by a m or less r\gh approximation1 or by ! me?od ( g5]al analogy f c]ta9 kn[n facts4 ,x w be se51 f :at has be5 said 9 previ\s *apt]s1 t ,mr4 ,l[ell1 9 8 book1 has us$ ! latt] me?od1 &1 by tak+ ! pres5ce ( wat] & wat]-vap\r 9 ,m>s z prov$ by ! behavi\r ( ! sn[-caps & ! blui% col\r t results f _! melt+1 has d$uc$ a temp]ature above ! freez+ po9t ( wat]1 z preval5t 9 ! equatorial regions p]man5tly1 & 9 ! temp]ate & arctic zones dur+ a portion ( ea* ye>4 ,mr4 ,l[ell's ,ma!matical ,inve/igation ( ! ,problem4 ,b z ?is result has be5 held to be bo? improbable 9 itself & f\nd$ on no valid evid5ce1 he has n[1 9 ! ,london1 ,ed9burgh1 & ,dubl9 ,philosophical ,magaz9e ( ,july #aijg1 publi%$ an elaborate pap] ( #ae pages1 entitl$ ,a ,g5]al ,me?od = ,evaluat+ ! ,surface-,temp]atures ( ! ,planets2 ) special ref]5ce to ! ,temp]ature ( ,m>s1 by ,pr(essor ,p]cival ,l[ell2 & 9 ?is pap]1 by :at purports to be /rict ma!matical reason+ bas$ on ! mo/ rec5t discov]ies z to ! laws ( heat1 z well z on measurem5ts or e/imates ( ! v>i\s elem5ts & con/ants us$ 9 ! calculations1 he arrives at a conclusion /rik+ly accordant ) t put =w>d 9 ! rec5tly publi%$ volume4 ,hav+ myself nei!r ma!matical nor physical k suffici5t to enable me to criticise ?is elaborate pap]1 except on a few po9ts1 ,i w "h limit myself to giv+ a %ort acc\nt ( x1 s z to expla9 its me?od ( proc$ure2 aft] :i* ,i may add a few notes on :at seem to me d\btful po9ts2 :ile ,i also hope to be able to give ! op9ions ( "s m compet5t critics ?an myself4 ,mr4 ,l[ell's ,mode ( ,e/imat+ ! ,surface-temp]ature ( ,m>s4 ,! au?or fir/ /ates1 t ,pr(essor ,"y1 9 8 ,g5]al ,a/ronomy 7#ahih71 makes ! mean temp]ature ( ,m>s #bbc4f absolute1 by us+ ,newton's law ( heat be+ radiat$ 9 proportion to temp]ature1 & #cfc abs4 7-#if ,f47 by ,dulong & ,petit's law2 b adds1 t a clos] det]m9ation has be5 made by ,pr(essor ,m\lton1 us+ ,/efan's law1 t radiation is z ! _/#d? p[] ( ! temp]ature1 :5ce results a mean temp]ature (-#ca ,f4 ,^! e/imates assume id5tity ( atmosph]ic conditions ( ,m>s & ! ,e>?4 ,b z none ( ^! e/imates take acc\nt ( ! _m complex factors :i* int]f]e ) su* direct & simple calculations1 ,mr4 ,l[ell !n proce$s to enunciate !m1 & "w out ma!matically ! effects !y produce3 7#a7 ,! :ole radiant en]gy ( ! sun on /rik+ a planet becomes divid$ z foll[s3 ,"p is reflect$ back into space1 "p absorb$ by ! atmosph]e1 "p transmitt$ to ! surface ( ! planet4 ,?is surface aga9 reflects a portion & only ! balance left goes to w>m ! planet4 7#b7 ,to solve ?is complex problem we are help$ by ! alb$oes or intr9sic brilliancy ( ! planets1 :i* dep5d on ! proportion ( ! visible rays :i* are reflect$ & :i* det]m9es ! comp>ative brightness ( _! respective surfaces4 ,we also h to f9d ! ratio ( ! invisible to ! visible rays & ! heat+ p[] ( ea*4 7#c7 ,he !n ref]s to ! act9omet] & pyroheliomet]1 in/rum5ts = measur+ ! actual heat d]iv$ f ! sun1 & also to ! ,bolomet]1 an in/rum5t inv5t$ by ,pr(essor ,langley = measur+ ! invisible heat rays1 :i* he has prov$ to ext5d to m ?an ?ree times ! l5g? ( ! :ole heat-spectrum z previ\sly kn[n1 & has also %[n t ! invisible rays contribute #fh p] c5t1 ( ! sun's total en]gy4#i ,footnote #i3 ,= a %ort acc\nt ( ?is rem>kable in/rum5t1 see my ,wond]ful ,c5tury1 new ed41 pp4 #adc-ade4 7#d7 ,!n foll[s an elaborate e/imate ( ! loss ( heat dur+ ! passage ( ! sun's rays ?r\gh our atmosph]e f exp]im5ts made at diff]5t altitudes & f ! e/imat$ reflective p[] ( ! v>i\s p>ts ( ! e>?'s surface--rocks & soil1 ocean1 =e/ & sn[--! f9al result be+ t ?ree-f\r?s ( ! :ole sun-heat is reflect$ back into space1 =m+ our alb$o1 :ile only "o-f\r? is absorb$ by ! soil & goes to w>m ! air & det]m9e our mean temp]ature4 7#e7 ,we n[ h ano!r elaborate e/imate ( ! comp>ative am\nts ( heat actually receiv$ by ,m>s & ! ,e>?1 dep5d5t on _! v diff]5t am\nts ( atmosph]e1 & ?is e/imate dep5ds almo/ :olly on ! comp>ative alb$oes1 t ( ,m>s1 z obs]v$ by a/ronom]s be+ #j4bg1 :ile ours has be5 e/imat$ 9 a totally diff]5t way z be+ #j4ge1 :5ce he concludes t ne>ly ?ree-f\r?s ( ! sun-heat t ,m>s receives rea*es ! surface & det]m9es its temp]ature1 :ile we get only "o-f\r? ( our total am\nt4 ,!n by apply+ ,/efan's law1 t ! radiation is z ! #d? p[] ( ! surface temp]ature1 he rea*es ! f9al result t ! actual heat+ p[] at ! surface ( ,m>s is consid]ably m ?an on ! ,e>?1 & w\ld produce a mean temp]ature ( #gb ,f41 if x 7 n = ! great] cons]vative or blanket+ p[] ( our d5s] & m wat]-lad5 atmosph]e4 ,! diff]5ce produc$ by ?is latt] fact he m9imises by dwell+ on ! probability ( a great] proportion ( c>bonic-acid gas & wat]-vap\r 9 ! ,m>tian atmosph]e1 & ?us br+s d[n ! mean temp]ature ( ,m>s to #dh ,f41 :i* is almo/ exactly ! same z t ( ! s\!rn half ( ,engl&4 ,he has also1 z ! result ( obs]vations1 r$uc$ ! probable d5sity ( ! atmosph]e ( ,m>s to #b-a_/b in*es ( m]cury1 or only "o-twelf? ( t ( ! ,e>?4 ,critical ,rem>ks on ,mr4 ,l[ell's ,pap]4 ,! la/ "p ( ?is pap]1 indicat$ "u p>s4 #d & #e1 is ! mo/ elaborate1 occupy+ eight pages1 & x conta9s mu* t seems unc]ta91 if n errone\s4 ,9 p>ticul>1 x seems v unlikely t "u a cle> sky ov] ! :ole e>? we %\ld only receive at ! sea-level #j4bc ( ! sol> rays :i* ! e>? int]cepts 7p4 #afg74 ,^! data l>gely dep5d on obs]vations made 9 ,cali=nia & o!r p>ts ( ! s\!rn ,unit$ ,/ates1 :]e ! l[] atmosph]e is exceptionally du/-lad54 ,till we h simil> obs]vations made 9 ! tropical =e/-regions1 :i* cov] s l>ge an area1 & :]e ! atmosph]e is purifi$ by frequ5t ra9s1 & also on ! prairies & ! great oceans1 we _c tru/ ^! v local obs]vations = g5]al conclusions affect+ ! :ole e>?4 ,lat]1 9 ! same article 7p4 #agj71 ,mr4 ,l[ell says3 ,cl\ds transmit approximately #bj p] c5t4 ( ! heat rea*+ !m3 a cle> sky at sea-level #fj p] c5t4 ,z ! sky is half ! "t cl\dy ! mean transmission is #ce p] c5t4 ,^! /atem5ts seem incompatible ) t quot$ above4 ,! figure he uses 9 8 calculations = ! actual alb$o ( ! e>?1 #j4ge1 is also n only improbable1 b almo/ self-contradictory1 because ! alb$o ( cl\d is #j4gb1 & t ( ! great cl\d-cov]$ planet1 ,jupit]1 is giv5 by ,l[ell z #j4ge1 :ile ,zolln] made x only #j4fb4 ,aga91 ,l[ell gives ,v5us an alb$o ( #j4ib1 :ile ,zolln] made x only #j4ej & ,mr4 ,gore #j4fe4 ,?is %[s ! extreme unc]ta9ty ( ^! e/imates1 :ile ! fact t bo? ,v5us & ,jupit] are :olly cl\d-cov]$1 :ile we are only half-cov]$1 r5d]s x almo/ c]ta9 t our alb$o is f> less ?an ,mr4 ,l[ell makes x4 ,x is evid5t t ma!matical calculations f\nd$ ^u su* unc]ta9 data _c yield tru/wor?y results4 ,b ?is is by no means ! only case 9 :i* ! data employ$ 9 ?is pap] are ( unc]ta9 value4 ,ev]y:]e we meet ) figures ( some:at d\btful accuracy4 ,"h we h somebody's 'e/imate' quot$1 !re ano!r p]son's 'obs]vation1' & ^! are adopt$ )\t fur!r rem>k & us$ 9 ! v>i\s calculations lead+ to ! result above quot$4 ,x requires a practis$ ma!matician1 & "o fully acqua9t$ ) ! ext5sive lit]ature ( ?is subject1 to exam9e ^! v>i\s data1 & track !m ?r\gh ! maze ( =mulae & figures s z to det]m9e to :at ext5t !y affect ! f9al result4 ,!re is h[ev] "o curi\s ov]sight :i* ,i mu/ ref] to1 z x is a po9t to :i* ,i h giv5 mu* att5tion4 ,n only does ,mr4 ,l[ell assume1 z 9 8 book1 t ! 'sn[s' ( ,m>s consi/ ( froz5 wat]1 & t !re=e !re is wat] on its surface & wat]-vap\r 9 its atmosph]e1 n only does he ignore altoge!r ,dr4 ,john/one ,/oney's calculations ) reg>d to x1 :i* ,i h already ref]r$ to1 b he uses t]ms t imply t wat]-vap\r is "o ( ! heavi] compon5ts ( our atmosph]e4 ,! passage is at p4 #afh ( ! ,philosophical ,magaz9e4 ,aft] /at+ t1 ow+ to ! v small b>ometric pressure 9 ,m>s1 wat] w\ld boil at #aaj ,f41 he adds3 ,! sublimation at l[] temp]atures w\ld be correspond+ly increas$4 ,consequ5tly ! am\nt ( wat]-vap\r 9 ! ,m>tian air mu/ on t score be relatively great] ?an our own4 ,!n foll[s ?is rem>kable passage3 ,c>bon-dioxide1 because ( its great] specific gravity1 w\ld also be 9 relatively great] am\nt s f> z ?is cause is consid]$4 ,= ! planet w\ld "p1 caet]is p>ibus1 ) its light] gases ! quicke/4 ,:5ce z reg>ds bo? wat]-vap\r & c>bon-dioxide we h reason to ?9k !m 9 relatively great] quantity ?an 9 our own air at correspond+ b>ometric pressure4 ,i _c und]/& ?is passage except z imply+ t 'wat]-vap\r & c>bon-dioxide' are among ! heavi] & n among ! light] gases ( ! atmosph]e--^? :i* ! planet 'p>ts ) quicke/4' ,b ?is is j :at wat]-vap\r is1 be+ a little less ?an two-?irds ! weight ( air 7#j4fbbe71 & "o ( ^? :i* ! planet w\ld "p ) ! quicke/1 & :i*1 accord+ to ,dr4 ,john/one ,/oney1 x loses altoge!r4 99 99 99 99 99 ,note on ,pr(essor ,l[ell's article 9 ! ,philosophical ,magaz9e2 by ,j4,h4 ,poynt+1 ,f4,r4,s41 ,pr(essor ( ,physics 9 ! ,univ]sity ( ,birm+ham4 ,i ?9k ,pr(essor ,l[ell's results are errone\s ?r\gh 8 neglect ( ! heat /or$ 9 ! air by its absorption ( radiation bo? f ! sun & f ! surface4 ,! air ?us heat$ radiates to ! surface & keeps up ! temp]ature4 ,i h s5t to ! ,philosophical ,magaz9e a pap] 9 :i* ,i ?9k x is %[n t :5 ! radiation by ! atmosph]e is tak5 into acc\nt ! results are entirely *ang$4 ,! temp]ature ( ,m>s1 ) ,pr(essor ,l[ell's data1 /ill comes out f> bel[ ! freez+-po9t--/ill fur!r bel[ ?an ! increas$ di/ance alone w\ld make x4 ,inde$1 ! l[] temp]ature on elevat$ regions ( ! e>?'s surface w\ld lead u to expect ?is4 ,i ?9k x is impossible to raise ! temp]ature ( ,m>s to any?+ l ! value obta9$ by ,pr(essor ,l[ell1 unless we assume "s quality 9 8 atmosph]e entirely diff]5t f any f\nd 9 our own atmosph]e4 ,j4,h4 ,,poynt+4 ,octob] #ai1 #aijg4 ,,*apt] ,,vi4 ,a ,,new ,,e/imate ,,( ,,! ,,temp]ature ,,( ,,m>s4 ,:5 we are pres5t$ ) a complex problem dep5d+ on a great numb] ( imp]fectly asc]ta9$ data1 we may (t5 *eck ! results ?us obta9$ by ! comp>ison ( cases 9 :i* "s ( ! m important ( ^! data are id5tical1 :ile o!rs are at a maximum or a m9imum4 ,9 ! pres5t case we c d ?is by a consid]ation ( ! ,moon z comp>$ ) ! ,e>? & ) ,m>s4 ,langley's ,det]m9ation ( ! ,moon's ,temp]ature4 ,9 ! moon we see ! conditions t prevail 9 ,m>s bo? exagg]at$ & simplifi$4 ,m>s has a v scanty atmosph]e1 ! moon none at all1 or if !re is "o x is s excessively scanty t ! mo/ ref9$ obs]vations h n detect$ x4 ,all ! complications aris+ f ! possible nature ( ! atmosph]e1 & its complex effects ^u reflection1 absorption1 & radiation are ?us elim9at$4 ,! mean di/ance ( ! moon f ! sun be+ id5tical ) t ( ! e>?1 ! total am\nt ( heat int]cept$ mu/ also be id5tical2 only 9 ?is case ! :ole ( x rea*es ! surface in/ead ( "o-f\r? only1 accord+ to ,mr4 ,l[ell's e/imate = ! e>?4 ,n[1 by ! mo/ ref9$ obs]vations ) 8 ,bolomet]1 ,mr4 ,langley 0 able to det]m9e ! temp]ature ( ! moon's surface expos$ to undimm$ sun%9e = f\rte5 days toge!r2 & he f\nd t1 ev5 9 t portion ( x on :i* ! sun 0 %9+ almo/ v]tically1 ! temp]ature r>ely rose above ! freez+ po9t ( wat]4 ,h[ev] extraord9>y ?is result may seem1 x is really a /rik+ confirmation ( ! accuracy ( ! g5]al laws det]m9+ temp]ature :i* ,i h endeav\r$ to expla9 9 ! prec$+ *apt]4 ,= ! same surface :i* has _h f\rte5 days ( sun%9e has also _h a prec$+ f\rte5 days ( d>kness1 dur+ :i* ! heat :i* x _h accumulat$ 9 its surface lay]s w\ld h be5 lo/ by free radiation into /ell> space4 ,x ?us acquires dur+ its day a maximum temp]ature ( only #dia ,f4 absolute1 :ile its m9imum1 aft] #ad days' cont9u\s radiation1 mu/ be v l[1 & is1 ) mu* reason1 suppos$ to approa* ! absolute z]o4 ,rapid ,loss ( ,heat by ,radiation on ! ,e>?4 ,9 ord] bett] to compreh5d :at ?is m9imum may be "u extreme conditions1 x w be useful to take note ( ! effects x actually produces on ! e>? 9 places :]e ! conditions are ne>e/ to ^? exi/+ on ! moon or on ,m>s1 ?\gh nev] q equall+1 or ev5 approa*+ v ne> !m4 ,x is 9 our great des]t regions1 & especially on high plateaux1 t extreme aridity prevails1 & x is 9 su* di/ricts t ! diff]5ces betwe5 day & night temp]atures rea* _! maximum4 ,x is /at$ by geograph]s t 9 p>ts ( ! ,great ,sah>a ! surface temp]ature is sometimes #aej ,f41 :ile dur+ ! night x falls ne>ly or q to ! freez+ po9t--a diff]5ce ( #aah degrees 9 little m ?an #ab h\rs4#aj ,9 ! high des]t pla9s ( ,c5tral ,asia ! extremes are said to be ev5 great]4#aa ,aga91 9 8 ,univ]sal ,geography1 ,reclus /ates t 9 ! ,arm5ian ,highl&s ! !rmomet] oscillates betwe5 #ac ,f4 & #aab;,f4 ,we may !re=e1 )\t any fe> ( exagg]ation1 take x z prov$ t a fall ( #ajj ,f4 9 twelve or fifte5 h\rs n infrequ5tly occurs :]e !re is a v dry & cle> atmosph]e p]mitt+ cont9u\s insolation by day & rapid radiation by night4 ,footnote #aj3 ,kei? ,john/on's ',africa' 9 ,/an=d's ,comp5dium4 ,footnote #aa3 ,*amb]s's ,encyclopa$ia1 ,art4 ',des]ts4' ,n[1 z x is admitt$ t our d5se atmosph]e1 h[ev] dry & cle>1 absorbs & reflects "s consid]able portion ( ! sol> heat1 we %all c]ta9ly und]e/imate ! radiation f ! moon's surface dur+ its long night if we take z ! basis ( our calculation a l[]+ ( temp]ature am\nt+ to #ajj ,f4 dur+ twelve h\rs1 z n unfrequ5tly occurs ) u4 ,us+ ^! data--) ,/efan's law ( decrease ( radiation z ! #d? p[] ( ! temp]ature--a ma!matical fri5d f9ds t ! temp]ature ( ! moon's surface w\ld be r$uc$ dur+ ! lun> night to ne>ly #bjj ,f4 absolute 7equal to-#beh ,f474 ,m ,rapid ,loss ( ,heat by ! ,moon4 ,al?\gh su* a calculation z ! above may af=d u a good approximation to ! rate ( loss ( heat by ,m>s ) its v scanty atmosph]e1 we h n[ good evid5ce t 9 ! case ( ! moon ! loss is mu* m rapid4 ,two indep5d5t work]s h inve/igat$ ?is subject ) v accordant results--,dr4 ,bo$dick]1 ) ,"l ,rosse's #c-;foot reflector & a ,!rmopile to measure ! heat1 & ,mr4 ,frank ,v1 ) a glass reflector ( #ab in*es diamet] & ! ,bolomet] inv5t$ by ,mr4 ,langley4 ,! v /rik+ & unexpect$ fact 9 :i* ^! obs]v]s agree is ! sudd5 disappe>ance ( mu* ( ! /or$-up heat dur+ ! comp>atively %ort duration ( a total eclipse ( ! moon--less ?an two h\rs ( complete d>kness1 & ab\t twice t p]iod ( p>tial obscuration4 ,dr4 ,bo$dick] 0 unable to detect any appreciable heat at ! p]iod ( greate/ obscuration2 b1 ow+ to ! extreme s5sitiv5ess ( ! ,bolomet]1 ,mr4 ,v asc]ta9$ t ^? p>ts ( ! surface :i* _h be5 longe/ 9 ! %ad[ /ill emitt$ heat to ! am\nt ( "o p] c5t4 ( ! heat to be expect$ f ! full moon4 ,?is h[ev] is ! am\nt ( radiation measur$ by ! ,bolomet]1 & to get ! temp]ature ( ! radiat+ surface we mu/ apply ,/efan's law ( ! #d? p[]4 ,h5ce ! temp]ature ( ! moon's d>k surface w be ! f\r? root ( 7#a ov] #ajj7 #a ov] #c4b ,a ( ! highe/ temp]ature 7:i* we may take at ! freez+-po9t1 #dia ,f4 abs471 or #aed ,f4 abs41 j bel[ ! liquefaction po9t ( air4 ,?is is ab\t #ej l[] ?an ! am\nt f\nd by calculation f our mo/ rapid radiation2 & z ?is am\nt is produc$ 9 a few h\rs1 x is n too mu* to expect t1 :5 cont9u$ = m ?an two weeks 7! lun> night71 x might rea* a temp]ature suffici5t to liquefy hydrog5 7#fj ,f4 abs471 or p]haps ev5 bel[ x4 ,note ,a3 ,la,tex m>kup root #d ( #a ov] #ajj #a ov] #c4b ,!ory ( ! ,moon's ,orig94 ,?is extremely rapid loss ( heat by radiation1 at fir/ sight s improbable z to be almo/ incr$ible1 may p]haps be to "s ext5t expla9$ by ! physical con/itution ( ! moon's surface1 :i*1 f a !oretical po9t ( view1 does n appe> to h receiv$ ! att5tion x des]ves4 ,x is cle> t our satellite has be5 long subject$ to volcanic eruptions ov] its :ole visible face1 & ^! h evid5tly be5 ( an explosive nature1 s z to build up ! v l(ty cones & crat]s1 z well z ?\s&s ( small] ones1 :i*1 ow+ to ! abs5ce ( any degrad+ or d5ud+ ag5cies1 h rema9$ pil$ up z !y 7 fir/ =m$4 ,?is highly volcanic /ructure c1 ,i ?9k1 be well expla9$ by an orig9 su* z t attribut$ to x by ,sir ,george ,d>w91 & :i* has be5 s well describ$ by ,sir ,rob]t ,ball 9 8 small volume1 ,"t & ,tide4 ,^! a/ronom]s adduce /rong evid5ce t ! e>? once rotat$ s rapidly t ! equatorial protub]ance 0 almo/ at ! po9t ( sep>ation f ! planet z a r+4 ,be=e ?is occurr$1 h[ev]1 ! t5sion 0 s great t "o l>ge portion ( ! protub]ance :]e x 0 weake/ broke away1 & began to move ar\nd ! e>? at "s consid]able di/ance f x4 ,z ab\t #a_/ej ( ! bulk ( ! e>? ?us escap$1 x mu/ h consi/$ ( a consid]able portion ( ! solid cru/ & a mu* l>g] quantity ( ! liquid or semi-liquid int]ior1 toge!r ) a proportionate am\nt ( ! gases :i* we "k =m$1 & /ill =m1 an important "p ( ! e>?'s sub/ance4 ,z ! surface lay]s ( ! e>? mu/ h be5 ! lighte/1 !y w\ld necess>ily1 :5 brok5 up by ?is gigantic convulsion1 h come toge!r to =m ! ext]ior ( ! new satellite1 & be soon adju/$ by ! =ces ( gravity & tidal di/urbance into a m or less irregul> sph]oidal =m1 all ^: int]/ices & cavities w\ld be fill$ up & connect$ toge!r by ! liquid or semi-liquid mass =c$ up betwe5 !m4 ,!nce-=w>d1 z ! moon increas$ its di/ance & r$uc$ its "t ( rotation1 9 ! way expla9$ by ,sir ,rob]t ,ball1 !re w\ld necess>ily comm5ce a process ( escape ( ! imprison$ gases at e fissure & at all po9ts & l9es ( weakness1 giv+ rise to num]\s volcanic outlets1 :i*1 be+ subject$ only to ! small =ce ( lun> gravity 7only "o-six? t ( ! e>?71 w\ld1 9 ! c\rse ( ages1 pile up ^? gigantic cones & ridges :i* =m its great *>act]i/ic4 ,b ?is small gravitative p[] ( ! moon w\ld prev5t its reta9+ on its surface any ( ! gases =m+ our atmosph]e1 :i* w\ld all escape f x & probably be recaptur$ by ! e>?4 ,by no process ( ext]nal aggregation ( solid matt] to su* a relatively small am\nt z t =m+ ! moon1 ev5 if ! aggregation 0 s viol5t z to produce heat en\gh to cause liquefaction1 c\ld any su* long-cont9u$ volcanic action arise by gradual cool+1 9 ! abs5ce ( int]nal gases4 ,!re might be fissures1 & ev5 "s outfl[s ( molt5 rock2 b )\t imprison$ gases1 & especially )\t wat] & wat]-vap\r produc+ explosive outbur/s1 c\ld any su* am\nt ( scoriae & a%es be produc$ z 7 necess>y = ! build+ up ( ! va/ volcanic cones1 crat]s1 & crat]lets we see ^u ! moon's surface4 ,i am n aw>e t ei!r ,sir ,rob]t ,ball or ,sir ,george ,d>w9 h adduc$ ?is highly volcanic condition ( ! moon's surface z a ph5om5on :i* c only be expla9$ by our satellite hav+ be5 ?r[n (f a v mu* l>g] body1 ^: gravitative =ce 0 suffici5t to acquire & reta9 ! enorm\s quantity ( gases & ( wat] :i* we possess1 & :i* are absolutely ess5tial = t special =m ( cone-build+ volcanic action :i* ! moon exhibits 9 s pre-em95t a degree4 ,yet x seems to me cle>1 t "s su* hypo!tical orig9 = our satellite w\ld h _h to be assum$ if ,sir ,george ,d>w9 _h n d$uc$ x by means ( purely ma!matical argum5t bas$ ^u a/ronomical facts4 ,return+ n[ to ! problem ( ! moon's temp]ature1 ,i ?9k ! ph5om5a ?is pres5ts may be 9 "p due to ! mode ( =mation "h describ$4 ,=1 its entire surface be+ ! result ( long-cont9u$ gase\s explosions1 all ! volcanic products--scoriae1 pumice1 & a%es--w\ld necess>ily be highly por\s ?r\gh\t2 &1 nev] hav+ be5 compact$ by wat]-action1 z on ! e>?1 & !re hav+ be5 no w9ds to c>ry ! f9] du/ s z to fill up _! pores & fissures1 ! :ole ( ! surface mat]ial to a v consid]able dep? mu/ be loose & por\s to a high degree4 ,?is condition has be5 fur!r increas$ ow+ to ! small p[] ( gravity & ! extreme irregul>ity ( ! surface1 consi/+ v l>gely ( l(ty cones & ridges v loosely pil$ up to enorm\s heights4 ,n[ ?is condition ( ! sub/ance ( ! moon's surface is su* z w\ld produce a high specific heat1 s t x w\ld absorb a l>ge am\nt ( heat 9 proportion to ! rise ( temp]ature produc$1 ! heat be+ conduct$ d[nw>ds to a consid]able dep?4 ,ow+1 h[ev]1 to ! total abs5ce ( atmosph]e radiation w\ld v rapidly cool ! surface1 b aft]w>ds m sl[ly1 bo? on acc\nt ( ! action ( ,/efan's law & because ! heat /or$ up 9 ! deep] portions c\ld be c>ri$ to ! surface by conduction only1 & ) extreme sl[ness4 ,v's ,rese>*es on ! ,moon's ,heat4 ,! results ( ! eclipse obs]vations are support$ by ! detail$ exam9ation ( ! surface-temp]ature ( ! moon by ,mr4 ,v 9 8 ,prize ,essay on ! ,di/ribution ( ! ,moon's ,heat 7publi%$ by ! ,utre*t ,society ( ,arts & ,sci5ces 9 #ahia74 ,he %[s1 by a diagram ( ! ',phase-curve1' t at ! comm5cem5t ( ! ,lun> day ! surface j )9 ! illum9at$ limb has acquir$ ab\t #a_/g ( its maximum temp]ature1 or ab\t #gj ,f4 abs4 ,z ! surface expos$ to ! ,bolomet] at ea* obs]vation is ab\t #a_/cj ( ! moon's surface1 & 9 ord] to ensure accuracy ! in/rum5t has to be direct$ to a spot ly+ :olly )9 ! edge ( ! moon1 x is evid5t t ! surface measur$ has already be5 = sev]al h\rs expos$ to oblique sun%9e4 ,! curve ( temp]ature !n rises gradually & aft]w>ds m rapidly1 till x atta9s its maximum 7( ab\t #cj to #dj ,f47 a few h\rs be=e noon4 ,?is1 ,mr4 ,v ?9ks1 is due to ! fact t ! half ( ! moon's face fir/ illum9at$ = u has1 on ! av]age1 a d>k] surface ?an t ( ! aft]noon1 or second qu>t]1 dur+ :i* ! curve desc5ds n q s rapidly1 ! temp]ature ne> sunset be+ only a little high] ?an t ne> sunrise4 ,?is rapid fall :ile expos$ to oblique sun%9e is q 9 h>mony ) ! rapid loss ( heat dur+ ! few h\rs ( d>kness dur+ an eclipse1 bo? %[+ ! prepot5cy ( radiation ov] insolation on ! moon4 ,two o!r diagrams %[ ! di/ribution ( heat at ! "t ( full-moon1 "o half ( ! curve %[+ ! temp]atures along ! equator f ! edge ( ! disc to ! c5tre1 ! o!r along a m]idian f ?is c5tre to ! pole4 ,?is diagram 7"h reproduc$7 exhibits ! quick rise ( temp]ature ( ! oblique rim ( ! moon & ! ne>ly uni=m heat ( ! c5tral half ( its surface2 ! dim9ution ( heat t[>ds ! pole1 h[ev]1 is sl[] = ! fir/ half & m rapid = ! latt] portion4 ,x is an int]e/+ fact t ! temp]ature ne> ! m>g9 ( ! full-moon increases t[>ds ! c5tre m rapidly ?an x does :5 ! same p>ts are obs]v$ dur+ ! e>ly phases ( ! fir/ qu>t]4 ,mr4 ,v expla9s ?is diff]5ce z be+ due to ! fact t ! full-moon to its v edges is fully illum9at$1 all ! %ad[s ( ! ridges & m\nta9s be+ ?r[n v]tically or obliquely beh9d !m4 ,we ?us measure ! heat reflect$ f ! :ole visible surface4 ,b at new moon1 & some:at beyond ! fir/ qu>t]1 ! deep %ad[s ?r[n by ! smalle/ cones & ridges1 z well z by ! l(tie/ m\nta9s1 cov] a consid]able portion ( ! visible surface1 ?us l>gely r$uc+ ! quantity ( light & heat reflect$ or radiat$ 9 our direction4 ,x is only at ! full1 !re=e1 t ! maximum temp]ature ( ! :ole lun> surface c be measur$4 ,x mu/ be consid]$ a pro( ( ! delicacy ( ! heat-measur+ in/rum5ts t ?is diff]5ce 9 ! curves ( temp]ature ( ! diff]5t p>ts ( ! moon's surface & "u diff]5t conditions is s cle>ly %[n4 ,! ,application ( ! ,prec$+ ,results to ! ,case ( ,m>s4 ,?is some:at l5g?y acc\nt ( ! actual /ate ( ! moon's surface & temp]ature is ( v great importance 9 our pres5t enquiry1 because x %[s u ! extraord9>y diff]5ce 9 mean & extreme temp]atures ( two bodies situat$ at ! same di/ance f ! sun1 & !re=e receiv+ exactly ! same am\nt ( sol> heat p] unit ( surface4 ,we h le>n$ also :at are ! ma9 causes ( ?is almo/ incr$ible diff]5ce1 namely3 7#a7 a rem>kably rugg$ surface ) por\s & probably cav]n\s rock-texture1 lead+ to extremely rapid radiation ( heat 9 ! "o2 z comp>$ ) a comp>atively ev5 & well-compact$ surface l>gely clad ) vegetation1 lead+ to comp>atively sl[ & gradual loss by radiation 9 ! o!r3 & 7#b71 ^! results be+ greatly int5sifi$ by ! total abs5ce ( a protect+ atmosph]e 9 ! =m]1 :ile a d5se & cl\dy atmosph]e ) an ev]-pres5t supply ( wat]-vap\r1 accumulates & equalises ! heat receiv$ by ! latt]4 ,! only o!r ess5tial diff]5ce 9 ! two bodies :i* may possibly aid 9 ! production ( ?is m>vell\s result1 is ! fact ( our day & night hav+ a mean l5g? ( #ab h\rs1 :ile ^? ( ! moon are ab\t #ad-a_/b ( our days4 ,b ! altoge!r unexpect$ fact1 9 :i* two indep5d5t enquir]s agree1 t dur+ ! few h\rs' duration ( a total eclipse ( ! moon s l>ge a proportion ( ! heat is lo/ by radiation r5d]s x almo/ c]ta9 t ! result+ l[ temp]ature w\ld be n v mu* less if ! moon _h a day & night ! same l5g? z our own4 ,! great lesson we le>n by ?is extreme contra/ ( conditions suppli$ to u by nature1 z if to enable u to solve "s ( h] problems1 is1 ! ov]:elm+ importance1 fir/1 ( a d5se & well-compact$ surface1 due to wat]-action & /rong gravitative =ce2 secondly1 ( a m or less g5]al coat ( vegetation2 &1 ?irdly1 ( a d5se vap\r-lad5 atmosph]e4 ,^! ?ree fav\rable conditions result 9 a mean temp]ature ( ab\t #fj ,f4 ) a range seldom exce$+ #dj above or bel[ x1 :ile ov] m ?an half ! l&-surface ( ! e>? ! temp]ature r>ely falls bel[ ! freez+ po9t4 ,on ! o!r h&1 we h a globe ( ! same mat]ials & at ! same di/ance f ! sun1 ) a maximum temp]ature ( freez+ wat]1 & a m9imum n v f> f ! absolute z]o1 ! mon?ly mean be+ probably mu* bel[ ! freez+ po9t ( c>bonic-acid gas--a diff]5ce entirely due to ! abs5ce ( ^! ?ree fav\rable conditions4 ,! ,special ,features ( ,m>s z influ5c+ ,temp]ature4 ,com+ n[ to ! special feature ( ,m>s & its probable temp]ature1 we f9d t mo/ writ]s h arriv$ at a v diff]5t conclusion f t ( ,mr4 ,l[ell1 :o himself quotes ,mr4 ,m\lton z an au?ority :o 'rec5tly1 by ! application ( ,/efan's law1' has f\nd ! mean temp]ature ( ?is planet to be-#ce ,f4 ,aga91 ,pr(essor ,j4,h4 ,poynt+1 9 8 lecture on ',radiation 9 ! ,sol> ,sy/em1' deliv]$ be=e ! ,briti% ,association at ,cambridge 9 #aijd1 gave an e/imate ( ! mean temp]ature ( ! planets1 arriv$ at f measurem5ts ( ! sun's emissive p[] & ! application ( ,/efan's law to ! di/ances ( ! sev]al planets1 & he ?us f9ds ! e>? to h a mean temp]ature ( #ag ,c4 7#fb-a_/b ,f47 & ,m>s "o (-#ch ,c4 7-#cf-a_/b ,f471 a wond]fully close approximation to ! mean temp]ature ( ! e>? z det]m9$ by direct measurem5t1 & !re=e1 presumably1 an equally ne> approximation to t ( ,m>s z dep5d5t on di/ance f ! sun1 & 'on ! supposition t x is e>?-l 9 all its conditions4' ,b we "k t x is f> f be+ e>?-l 9 ! v conditions :i* we h f\nd to be ^? :i* det]m9e ! extremely diff]5t temp]atures ( ! e>?1 & moon2 &1 z reg>ds ea* ( ^!1 we %all f9d t1 s f> z x diff]s f ! e>?1 x approximates to ! less fav\rable conditions t prevail 9 ! moon4 ,! fir/ ( ^! conditions :i* we h f\nd to be ess5tial 9 regulat+ ! absorption & radiation ( heat1 & ?us rais+ ! mean temp]ature ( a planet1 is a compact surface well cov]$ ) vegetation1 two conditions aris+ f1 & absolutely dep5d5t on1 an ample am\nt ( wat]4 ,b ,mr4 ,l[ell himself assures u1 z a fact ( :i* he has no d\bt1 t !re are no p]man5t bodies ( wat]1 great or small1 ^u ,m>s2 t ra91 & consequ5tly riv]s1 are totally want+2 t its sky is almo/ con/antly cle>1 & t :at appe> to be cl\ds are n =m$ ( wat]-vap\r b ( du/4 ,he dwells1 emphatically1 on ! t]rible des]t conditions ( ! great] "p ( ! surface ( ! planet4 ,t be+ ! case n[1 we h no "r to assume t x has ev] be5 o!rwise2 &1 tak+ full acc\nt ( ! fact1 nei!r d5i$ nor disput$ by ,mr4 ,l[ell1 t ! =ce ( gravity on ,m>s is n suffici5t to reta9 wat]-vap\r 9 its atmosph]e1 we mu/ conclude t ! surface ( t planet1 l t ( ! moon1 has be5 m\ld$ by "s =m ( volcanic action modifi$ probably by w9d1 b n by wat]4 ,add+ to ?is1 t ! =ce ( gravity on ,m>s is ne>] t ( ! moon ?an to t ( ! e>?1 & we may r reasonably conclude t its surface is =m$ ( volcanic matt] 9 a light & por\s condition1 & !re=e highly fav\rable = ! rapid loss ( surface heat by radiation4 ,! surface-conditions ( ,m>s are !re=e1 presumably1 mu* m l ^? ( ! moon ?an l ^? ( ! e>?4 ,! next condition fav\rable to ! /or+ up ( heat--a cov]+ ( vegetation--is almo/ c]ta9ly abs5t f ,m>s except1 possibly1 ov] limit$ areas & = %ort p]iods4 ,9 ?is feature also ! surface ( ,m>s approximates mu* ne>] to lun> ?an to e>?-conditions4 ,! ?ird condition--a d5se1 vap\r-lad5 atmosph]e--is also want+ 9 ,m>s4 ,= al?\gh x possesses an atmosph]e x is e/imat$ by ,mr4 ,l[ell 79 8 late/ article7 to h a pressure equival5t to only #b-a_/b in*es ( m]cury ) u1 giv+ x a d5sity ( only "o-twelf? "p t ( ours2 :ile aque\s vap\r1 ! *ief accumulator ( heat1 _c p]man5tly exi/ 9 x1 &1 not)/&+ repeat$ spectroscopic obs]vations = ! purpose ( detect+ x1 has nev] be5 prov$ to exi/4 ,i submit t ,i h n[ %[n f ! /atem5ts--& l>gely z ! result ( ! long-cont9u$ obs]vations--( ,mr4 ,l[ell himself1 t1 s f> z ! physical conditions ( ,m>s are kn[n to diff] f ^? ( ! e>?1 ! diff]5ces are all unfav\rable to ! cons]vation & fav\rable to ! dissipation ( ! scanty heat x receives f ! sun--t !y po9t unmi/akeably t[>ds ! temp]ature conditions ( ! moon r ?an to ^? ( ! e>?1 & t ! cumulative effect ( ^! adv]se conditions1 act+ ^u a heat-supply1 r$uc$ by sol> di/ance to less ?an "o-half ( ours1 mu/ result 9 a mean temp]ature 7z well z 9 ! extremes7 ne>] to t ( our satellite ?an to t ( our own e>?4 ,fur!r ,criticism ( ,mr4 ,l[ell's ,article4 ,we are n[ 9 a position to te/ "s fur!r conclusions ( ,mr4 ,l[ell's ,phil4 ,mag4 article by comp>ison ) actual ph5om5a4 ,we h se51 9 ! outl9e ,i h giv5 ( ?is article1 t he endeav\rs to %[ h[ ! small am\nt ( sol> heat receiv$ by ,m>s is c\nt]balanc$1 l>gely by ! great] transp>5cy to light & heat ( its ?9 & cl\dless atmosph]e1 & p>tially also by a great] cons]vative or 'blanket+' p[] ( its atmosph]e due to ! pres5ce 9 x ( a l>ge proportion ( c>bonic acid gas & aque\s vap\r4 ,! fir/ ( ^! /atem5ts may be admitt$ z a fact :i* he is entitl$ to dwell ^u1 b ! second--! pres5ce ( l>ge quantities ( c>bon-dioxide & aque\s vap\r is a pure hypo!sis unsupport$ by any item ( sci5tific evid5ce1 :ile 9 ! case ( aque\s vap\r x is directly oppos$ to admitt$ results f\nd$ ^u ! molecul> !ory ( gase\s ela/icity4 ,b1 al?\gh ,mr4 ,l[ell ref]s to ! cons]vative or 'blanket+' effect ( ! e>?'s atmosph]e1 he does n consid] or all[ = its v great cumulative effect1 z is /rik+ly %[n by ! comp>ison ) ! actual temp]ature conditions ( ! moon4 ,?is cumulative effect is due to ! cont9u\s reflection & radiation ( heat f ! cl\ds z well z f ! vap\r-lad5 /rata ( air 9 our l[] atmosph]e1 :i* latt]1 ?\gh v transp>5t to ! lum9\s & accompany+ heat rays ( ! sun1 are opaque to ! d>k heat-rays :e!r radiat$ or reflect$ f ! e>?'s surface4 ,we are !re=e 9 a position /rictly comp>able ) t ( ! int]ior ( "s huge glass h\se1 :i* n only becomes int5sely heat$ by ! direct rays ( ! sun1 b also to a less degree by reflect$ rays f ! sky & ^? radiat$ f ! cl\ds1 s t ev5 on a cl\dy or mi/y day its temp]ature rises _m degrees above t ( ! out] air4 ,su* a build+1 if ( l>ge size1 ( suitable =m1 & well protect$ at night by bl9ds or o!r cov]+1 might be s arrang$ z to accumulate heat 9 its soil & walls s z to ma9ta9 a tol]ably uni=m temp]ature ?\gh expos$ to a consid]able range ( ext]nal heat & cold4 ,x is to su* a p[] ( accumulation ( heat 9 our soil & l[] atmosph]e t we mu/ impute ! ov]:elm+ contra/ betwe5 our climate & t ( ! moon4 ,) u1 ! sol> heat t p5etrates our vap\r-lad5 & cl\dy atmosph]e is %ut 9 by t same atmosph]e1 accumulates !re = weeks & mon?s toge!r1 & c only sl[ly escape4 ,x is ?is great cumulative p[] :i* ,mr4 ,l[ell has n tak5 acc\nt (1 :ile he c]ta9ly has n e/imat$ ! enorm\s loss ( heat by free radiation1 :i* entirely neutralises ! effects ( increase ( sun-heat1 h[ev] great1 :5 ^! cumulative ag5cies are n pres5t4#ab ,footnote #ab3 ,! effects ( ?is 'cumulative' p[] ( a d5se atmosph]e are fur!r discuss$ & illu/rat$ 9 ! la/ *apt] ( ?is book1 :]e ,i %[ t ! univ]sal fact ( /eadily dim9i%+ temp]atures at high altitudes is due solely to ! dim9ution ( ?is cumulative p[] ( our atmosph]e1 & t f ?is cause alone ! temp]ature ( ,m>s mu/ be t :i* w\ld be f\nd on a l(ty plateau ab\t #ah1jjj feet high] ?an ! av]age ( ! peaks ( ! ,&es6 ,temp]ature on ,pol> ,regions ( ,m>s4 ,!re is also a fur!r consid]ation :i* ,i ?9k ,mr4 ,l[ell has altoge!r omitt$ to discuss4 ,:atev] may be ! mean temp]ature ( ,m>s1 we mu/ take acc\nt ( ! long nights 9 its pol> & high-temp]ate latitudes1 la/+ ne>ly twice z long z ours1 ) ! result+ l[]+ ( temp]ature by radiation into a con/antly cle> sky4 ,ev5 9 ,sib]ia1 9 ,lat4 #fg-a_/b,n4 a cold (-#hh;,f4 has be5 atta9$2 :ile ov] a l>ge portion ( ,n4 ,asia & ,am]ica above #fj ,lat4 ! mean ,janu>y temp]ature is f-#cj;,f4 to-#fj;,f41 & ! :ole subsoil is p]man5tly froz5 f a dep? ( #f or #g feet to sev]al hundr$s4 ,b ! w9t] temp]atures1 ov] ! same latitudes 9 ,m>s1 mu/ be v mu* l[]2 & x mu/ require a proportionally l>g] am\nt ( its feeble sun-heat to raise ! surface ev5 to ! freez+-po9t1 & an additional v l>ge am\nt to melt any consid]able dep? ( sn[4 ,b ?is id5tical area1 f a little bel[ #fj to ! pole1 is t occupi$ by ! sn[-caps ( ,m>s1 & ov] ! :ole ( x ! w9t] temp]ature mu/ be f> l[] ?an ! e>?-m9imum (-#hh;,f4 ,!n1 z ! ,m>tian summ] comes on1 !re is less ?an half ! sun-heat available to raise ?is l[ temp]ature aft] a w9t] ne>ly d\ble ! l5g? ( ours4 ,& :5 ! summ] does come ) its scanty sun-heat1 t heat is n accumulat$ z x is by our d5se & moi/ure-lad5 atmosph]e1 ! m>vell\s effects ( :i* we h already %[n4 ,yet ) all ^! adv]se conditions1 ea* assi/+ ! o!r to produce a climate approximat+ to t :i* ! e>? w\ld h if x _h no atmosph]e 7b reta9+ our sup]iority ov] ,m>s 9 receiv+ d\ble ! am\nt ( sun-heat71 we are ask$ to accept a mean temp]ature = ! m di/ant planet almo/ exactly ! same z t ( mild & equable s\!rn ,engl&1 & a disappe>ance ( ! va/ sn[fields ( its pol> regions z rapid & complete z :at occurs ) u6 ,if ! moon1 ev5 at its equator1 has n its temp]ature rais$ above ! freez+-po9t ( wat]1 h[ c ! m di/ant ,m>s1 ) its oblique noon-day sun fall+ ^u ! sn[-caps1 receive heat en\gh1 fir/ to raise _! temp]ature to #cb ,f41 & !n to melt ) m>k$ rapidity ! va/ froz5 pla9s ( its pol> regions8 ,mr4 ,l[ell is h[ev] s reg>dless ( ! ord9>y tea*+s ( meteorological sci5ce t he actually acc\nts = ! suppos$ mild climate ( ! pol> regions ( ,m>s by ! abs5ce ( wat] on its surface & 9 its atmosph]e4 ,he concludes 8 fif? *apt] ) ! foll[+ words3 ,c\ld our e>? b get rid ( its oceans1 we too might h temp]ate regions /ret*+ to ! poles4 ,"h he runs c\nt] to two ( ! be/-e/abli%$ laws ( t]re/rial climatology-- ! wond]ful equalis+ effects ( w>m ocean-curr5ts :i* are ! *ief ag5ts 9 dim9i%+ pol> cold2 ! equally /rik+ effects ( w>m moi/ w9ds d]iv$ f ^! oceans1 & ! great /oreh\se ( heat we possess 9 our vap\r-lad5 atmosph]e1 its vap\r be+ prim>ily d]iv$ f ^! same oceans6 ,b1 9 ,mr4 ,l[ell's op9ion1 all our meteorologi/s are q mi/ak54 ,our oceans are our great drawbacks4 ,only get rid ( !m & we %\ld enjoy ! exquisite climate ( ,m>s--) its abs5ce ( cl\ds & fog1 ( ra9 or riv]s1 & its delightful expanses ( p]5nial des]ts1 v>i$ t[>ds ! poles by a scanty sn[-fall 9 w9t]1 ! melt+ ( :i* might1 ) great c>e1 supply u ) ! necess>y moi/ure to gr[ :eat & cabbages = ab\t "o-t5?1 or m likely "o-hundr$?1 ( our pres5t population4 ,i hope ,i may be excus$ = n treat+ su* an argum5t s]i\sly4 ,! v>i\s consid]ations n[ advanc$1 especially ^? :i* %[ ! enorm\s cumulative & cons]vative effect ( our d5se & wat]-lad5 atmosph]e1 & ! disa/r\s effect--judg+ by ! actual condition ( ! moon--:i* ! loss ( x w\ld h ^u our temp]ature1 seem to me q suffici5t to demon/rate important errors 9 ! data or fallacies 9 ! complex ma!matical argum5t by :i* ,mr4 ,l[ell has attempt$ to uphold 8 views z to ! temp]ature & consequ5t climatic conditions ( ,m>s4 ,9 conclud+ ?is portion ( my discussion ( ! problem ( ,m>s1 ,i wi% to call att5tion to ! fact t my argum5t1 f\nd$ ^u a comp>ison ( ! physical conditions ( ! e>? & moon ) ^? ( ,m>s1 is dep5d5t ^u a small numb] ( g5]ally admitt$ sci5tific facts2 :ile ! conclusions drawn f ^? facts are simple & direct1 requir+ no ma!matical k to foll[ !m1 or to appreciate _! weight & cog5cy4 ,i claim = !m1 !re=e1 t !y are 9 no degree speculative1 b 9 _! data & me?ods exclusively sci5tific4 ,9 ! next *apt] ,i w put =w>d a sugge/ion z to h[ ! v curi\s m>k+s ^u ! surface ( ,m>s may possibly be int]pret$1 s z to be 9 h>mony ) ! planet's actual physical condition & its n improbable orig9 & pa/ hi/ory4 ,,*apt] ,,vii4 ,a ,,sugge/ion ,,z ,,to ,,! ',,canals' ,,( ,,m>s4 ,! special *>act]i/ics ( ! num]\s l9es :i* int]sect ! :ole ( ! equatorial & temp]ate regions ( ,m>s are1 _! /raightness comb9$ ) _! enorm\s l5g?4 ,x is ?is :i* has l$ ,mr4 ,l[ell to t]m !m 'non-natural features4' ,s*iap>elli1 9 8 e>li] draw+s1 %[$ !m curv$ & ( comp>atively great wid?4 ,lat]1 he f\nd !m to be /raight f9e l9es :5 se5 "u ! be/ conditions1 j z ,mr4 ,l[ell has always se5 !m 9 ! pure atmosph]e ( 8 obs]vatory4 ,bo? ( ^! obs]v]s 7 at fir/ d\btful ( _! reality1 b p]si/5t obs]vation cont9u$ at _m successive oppositions compell$ acceptance ( !m z actual features ( ! planet's disc4 ,s _m o!r obs]v]s h n[ se5 !m t ! objection ( unreality seems no long] valid4 ,mr4 ,l[ell urges1 h[ev]1 t _! p]fect /raightness1 _! extreme t5uity1 _! uni=mity ?r\gh\t _! :ole l5g?1 ! dual "* ( _m ( !m1 _! relation to ! 'oases' & ! =m & position ( ^! r\nd black spots1 are all pro(s ( artificiality & are sugge/ive ( design4 ,& consid]+ t "s ( !m are actually z long z f ,bo/on to ,san ,francisco1 & relatively to _! globe z long z f ,london to ,bombay1 8 objection t no natural ph5om5a )9 our k %[ su* regul>ity on su* a scale seems1 at fir/1 a mighty "o4 ,x is c]ta9ly true t we c po9t to no?+ exactly l !m ei!r on ! e>? or on ! moon1 & ^! are ! only two planet>y bodies we are 9 a position to comp>e ) ,m>s4 ,yet ev5 ^! d1 ,i ?9k1 af=d u "s h9ts t[>ds an int]pretation ( ! my/]i\s l9es4 ,b z our k ( ! int]nal /ructure & pa/ hi/ory ev5 ( our e>? is /ill imp]fect1 t ( ! moon only conjectural1 & t ( ,m>s a p]fect blank1 x is n p]haps surpris+ t ! surface-features ( ! latt] d n correspond ) ^? ( ei!r ( ! o!rs4 ,mr4 ,pick]+'s ,sugge/ion4 ,! be/ clue to a natural int]pretation ( ! /range features ( ! surface ( ,m>s is t sugge/$ by ! ,am]ican a/ronom] ,mr4 ,w4,h4 ,pick]+ 9 ,popul> ,a/ronomy 7#aijd74 ,briefly x is1 t bo? ! 'canals' ( ,m>s & ! rifts z well z ! lum9\s /reaks on ! moon are cracks 9 ! volcanic cru/1 caus$ by int]nal /resses due to ! action ( ! heat$ int]ior4 ,^! cracks he consid]s to be symmetrically arrang$ ) reg>d to small 'crat]lets' 7,mr4 ,l[ell's 'oases'7 because !y h orig9at$ f !m1 j z ! :ite /reaks on ! moon radiate f ! l>g] crat]s z c5tres4 ,he fur!r supposes t wat] & c>bon-dioxide issue f ! int]ior into ^! fissures1 &1 9 conjunction ) sunlight1 promote ! gr[? ( vegetation4 ,ow+ to ! v r>e atmosph]e1 ! vap\rs1 he ?9ks1 w\ld n asc5d b w\ld roll d[n ! outsides ( ! crat]lets & along ! bord]s ( ! canals1 ?us irrigat+ ! imm$iate vic9ity & s]v+ to promote ! gr[? ( "s =m ( vegetation :i* r5d]s ! canals & oases visible4#ac ,footnote #ac3 ,nature1 vol4 #gj1 p4 #ecf4 ,?is op9ion is especially important because1 next to ,mr4 ,l[ell1 ,mr4 ,pick]+ is p]haps ! a/ronom] :o has giv5 mo/ att5tion to ,m>s dur+ ! la/ fifte5 ye>s4 ,he 0 = "s "t at ,flag/aff ) ,mr4 ,l[ell1 & x 0 he :o discov]$ ! oases or crat]lets1 & :o orig9at$ ! idea t we did n see ! 'canals' !mselves b only ! vegetable gr[? on _! bord]s4 ,he also obs]v$ ,m>s 9 ! ,s\!rn ,hemisph]e at ,arequipa2 & he has s9ce made an elaborate /udy ( ! moon by means ( a specially con/ruct$ telescope ( #ace feet focal l5g?1 :i* produc$ a direct image on photographic plates ne>ly #af in*es 9 diamet]4#ad ,footnote #ad3 ,nature1 vol4 #gj1 ,may #e1 p4xi1 supplem5t4 ,x is cle> !re=e t ,mr4 ,l[ell's views z to ! artificial nature ( ! 'canals' ( ,m>s are n accept$ by an a/ronom] ( equal k & /ill wid] exp]i5ce4 ,yet ,pr(essor ,pick]+'s alt]native view is m a sugge/ion ?an an explanation1 because !re is no attempt to acc\nt = ! enorm\s l5g? & p]fect /raightness ( ! l9es on ,m>s1 s diff]5t f any?+ t is f\nd ei!r on our e>? or on ! moon4 ,!re mu/ evid5tly be "s great peculi>ity ( /ructure or ( conditions on ,m>s to acc\nt = ^! features1 & ,i %all n[ attempt to po9t out :at ?is peculi>ity is & h[ x may h aris54 ,! ,meteoritic ,hypo!sis4 ,dur+ ! la/ qu>t] ( a c5tury a consid]able *ange has come ov] ! op9ions ( a/ronom]s z reg>ds ! probable orig9 ( ! ,sol> ,sy/em4 ,! l>ge am\nt ( k ( ! /ell> univ]se1 & especially ( nebulae1 ( comets & ( meteor-/reams :i* we n[ possess1 toge!r ) _m o!r ph5om5a1 su* z ! con/itution ( ,saturn's r+s1 ! great numb] & ext5t ( ! m9or planets1 & g5]ally ( ! va/ am\nt ( matt] 9 ! =m ( meteor-r+s & meteoric du/ 9 & ar\nd our sy/em1 h all po9t$ to a diff]5t orig9 = ! planets & _! satellites ?an t =mulat$ by ,laplace z ! ,nebul> hypo!sis4 ,x is n[ se5 m cle>ly ?an at any e>li] p]iod1 t mo/ ( ! planets possess special *>act]i/ics :i* di/+ui% !m f "o ano!r1 & t su* an orig9 z ,laplace sugge/$--! sl[ cool+ & contraction ( "o va/ sun-mi/ or nebula1 besides pres5t+ inh]5t difficulties--_m ?9k !m impossibilities--9 itself does n af=d an adequate explanation ( ^! peculi>ities4 ,h5ce has aris5 :at is t]m$ ! ,meteoritic !ory1 :i* has be5 ably advocat$ = _m ye>s by ,sir ,norman ,locky]1 & ) "s unimportant modifications is n[ becom+ widely accept$4 ,briefly1 ?is !ory is1 t ! planets h be5 =m$ by ! sl[ aggregation ( solid p>ticles ar\nd c5tres ( greate/ cond5sation2 b z _m ( my read]s may be altoge!r unacqua9t$ ) x1 ,i w "h give a v cle> /atem5t ( :at x is1 f ,pr(essor ,j4,w4 ,gregory's presid5tial address to ! ,geological ,section ( ! ,briti% ,association ( ! pres5t ye>4 ,he began by say+ t ^! mod]n views 7 ( f> m practical use to m5 ( sci5ce ?an t ( ,laplace1 & t !y give u a hi/ory ( ! _w consi/5t ) ! actual records ( geology4 ,he !n cont9ues3 ,accord+ to ,sir ,norman ,locky]'s ,meteoritic ,hypo!sis1 nebulae1 comets1 & _m s-call$ />s consi/ ( sw>ms ( meteorites :i*1 ?\gh normally cold & d>k1 are heat$ by repeat$ collisions1 & s become lum9\s4 ,!y may ev5 be volatilis$ into gl[+ meteoric vap\r2 b 9 "t ?is heat is dissipat$1 & ! =ce ( gravity cond5ses a meteoritic sw>m into a s+le globe4 ',"s ( ! sw>ms are1' says ,locky]1 'truly memb]s ( ! sol> sy/em1' & "s ( ^! travel r\nd ! sun 9 ne>ly circul> orbits1 l planets4 ,!y may be reg>d$ z inf9itesimal planets1 & s ,*amb]la9 calls !m 'planetismals4' ,! planetismal !ory is a developm5t ( ! meteoritic !ory1 & pres5ts x 9 an especially attractive guise4 ,x reg>ds meteorites z v sp>sely di/ribut$ ?r\gh space1 & gravity z p[]less to collect !m into d5se gr\ps4 ,s x assigns ! p>5tage ( ! sol> sy/em to a spiral nebula compos$ ( planetismals1 & ! planets z =m$ f knots 9 ! nebula1 :]e _m planetismals _h be5 conc5trat$ ne> ! int]sections ( _! orbits4 ,^! gr\ps ( meteorites1 already z d5se z a sw>m ( bees1 7 !n pack$ clos] by ! influ5ce ( gravity1 & ! contract+ mass 0 heat$ by ! pressure1 ev5 above ! normal melt+-po9t ( ! mat]ial1 :i* 0 kept rigid by ! weight ( ! ov]ly+ lay]s4 ,n[1 adopt+ ?is !ory z ! la/ ^w ( sci5ce ^u ! subject ( ! orig9 ( planets1 we see t x af=ds imm5se scope = div]sity 9 results dep5d+ on ! total am\nt ( matt] available )9 ! range ( attraction ( an incipi5t planet>y mass1 & ! rates at :i* ?is matt] becomes available4 ,by a special comb9ation ( ^! two quantities 7:i* h almo/ c]ta9ly be5 diff]5t = ea* planet7 ,i ?9k we may be able to ?r[ "s light ^u ! /ructure & physical features ( ,m>s4 ,! ,probable ,mode ( ,orig9 ( ,m>s4 ,?is planet1 ly+ betwe5 two ( mu* great] mass1 has evid5tly _h less mat]ial f :i* to be =m$ by aggregation2 & if we assume--z 9 ! abs5ce ( evid5ce to ! contr>y we h a "r to d--t its beg9n+s 7 n mu* lat] 7or e>li]7 ?an ^? ( ! e>?1 !n its small] size %[s t x has 9 all probability aggregat$ v mu* m sl[ly4 ,b ! int]nal heat acquir$ by a planet :ile =m+ 9 ?is mann] w dep5d ^u ! rate at :i* x aggregates & ! velocity ) :i* ! planetismals' fall into x1 & ?is velocity w increase ) its mass & consequ5t =ce ( gravity4 ,9 ! e>ly /ages ( a planet's gr[? x w probably rema9 cold1 ! small am\nt ( heat produc$ by ea* impact be+ lo/ by radiation be=e ! next "o occurs2 & ) a small & sl[ly aggregat+ planet ?is condition w prevail till x approa*es its full size4 ,!n only w its gravitative =ce be suffici5t to cause incom+ matt] to fall ^u x ) s p[]ful an impact z to produce int5se heat4 ,fur!r1 ! compressive =ce ( a small planet w be a less effective heat-produc+ ag5cy ?an 9 ! case ( a l>g] "o4 ,! e>? we "k has acquir$ a l>ge am\nt ( int]nal heat1 probably suffici5t to liquefy its :ole int]ior2 b ,m>s has only "o-n9? "p ! mass ( ! e>?1 & x is q possible1 & ev5 probable1 t its comp>atively small attractive =ce w\ld nev] h liquefi$ or ev5 p]man5tly heat$ ! m c5tral portions ( its mass4 ,?is be+ admitt$1 ,i sugge/ ! foll[+ c\rse ( ev5ts z q possible1 & n ev5 improbable1 9 ! case ( ?is planet4 ,dur+ ! :ole ( its e>ly gr[?1 & till x acquir$ ne>ly its pres5t diamet]1 its rate ( aggregation 0 s sl[ t ! planetismals fall+ ^u x1 ?\gh !y might h be5 heat$ & ev5 p>tially liquefi$ by ! impact1 7 nev] 9 su* quantity z to produce any consid]able heat+ effect on ! :ole mass1 & ea* local rise ( temp]ature 0 soon lo/ by radiation4 ,! planet ?us grew z a solid & cold mass1 compact$ toge!r by ! impact ( ! incom+ matt] z well z by its sl[ly increas+ gravitative =ce4 ,b :5 x _h atta9$ to )9 p]haps #ajj1 p]haps #ej miles1 or less1 ( its pres5t diamet]1 a great *ange occurr$ 9 ! opportunity = fur!r gr[?4 ,"s l>ge & d5se sw>m ( meteorites1 p]haps conta9+ a numb] ( bodies ( ! size ( ! a/]oids1 came )9 ! range ( ! sun's attraction & 7 drawn by x into an orbit :i* cross$ t ( ,m>s at su* a small angle t ! planet 0 able at ea* revolution to capture a consid]able numb] ( !m4 ,! result might !n be t1 z 9 ! case ( ! e>?1 ! cont9u\s inp\r ( ! fre% matt] fir/ heat$1 & lat] on liquefi$ ! great] "p ( x z well p]haps z a ?9 lay] ( ! planet's orig9al surface2 s t :5 9 due c\rse ! :ole ( ! meteor-sw>m _h be5 captur$1 ,m>s _h acquir$ its pres5t mass1 b w\ld consi/ ( an int5sely heat$1 & ei!r liquid or pla/ic ?9 out] %ell re/+ ^u a cold & solid int]ior4 ,! size & position ( ! two rec5tly discov]$ satellites ( ,m>s1 :i* are believ$ to be n m ?an t5 miles 9 diamet]1 ! m remote revolv+ ar\nd its prim>y v little sl[] ?an ! planet rotates1 :ile ! ne>] "o1 :i* is consid]ably less di/ant f ! planet's surface ?an its own antipodes & revolves ar\nd x m ?an ?ree times dur+ ! ,m>tian day1 may p]haps be look$ ^u z ! remnants ( ! great meteor-sw>m :i* complet$ ! ,m>tian developm5t1 & :i* are p]haps !mselves de/9$ at "s di/ant p]iod to fall into ! planet4 ,%\ld future a/ronom]s witness ! ph5om5on ! effect produc$ ^u its surface w\ld be full ( in/ruction4 ,z ! result ( su* an orig9 z t sugge/$1 ,m>s w\ld possess a /ructure :i*1 9 ! ess5tial feature ( heat-di/ribution1 w\ld be ! v opposite ( t :i* is believ$ to *>act]ise ! e>?1 yet x might h be5 produc$ by a v slight modification ( ! same process4 ,?is peculi> heat-di/ribution1 toge!r ) a mu* small] mass & gravitative =ce1 w\ld lead to a v diff]5t developm5t ( ! surface & an altoge!r div]se geological hi/ory f ours1 :i* has ?r\gh\t be5 pr(\ndly influ5c$ by its heat$ int]ior1 its va/ supply ( wat]1 & ! cont9u\s physical & *emical reactions betwe5 ! int]ior & ! cru/4 ,^! reactions h1 9 our case1 be5 ( sub/antially ! same nature1 & v ne>ly ( ! same degree ( int5sity ?r\gh\t ! :ole va/ eons ( geological "t1 & !y h result$ 9 a wond]fully complex succession ( rock-=mations--volcanic1 plutonic1 & s$im5t>y--m or less int]m+l$ ?r\gh\t ! :ole s]ies1 "h rema9+ horizontal z :5 fir/ deposit$1 !re upheav$ or depress$1 fractur$ or cru%$1 incl9$ or contort$2 d5ud$ by ra9 & riv]s ) ! assi/ance ( heat & cold1 ( fro/ & ice1 9 an unceas+ s]ies ( *anges1 s t h[ev] v>i$ ! surface may be1 ) hill & dale1 pla9s & upl&s1 m\nta9 ranges & deep int]v5+ valleys1 ^! are z no?+ to ! div]sities ( int]ior /ructure1 z exhibit$ 9 ! sides ( e alp9e valley or precipit\s esc>pm5t1 & made kn[n to u by ! "w ( ! m9] & ! well-bor] 9 e "p ( ! _w4 ,/ructural ,/raight ,l9es on ! ,e>?4 ,! great *>act]i/ic ( ! e>?1 bo? on its surface & 9 its int]ior1 is ?us se5 to be extreme div]sity bo? ( =m & /ructure1 & ?is is fur!r int5sifi$ by ! v>i$ texture1 con/itution1 h>dness1 & d5sity ( ! v>i\s rocks & debris ( :i* x is compos$4 ,x is !re=e n surpris+ t1 ) su* a complex out] cru/1 we %\ld n[h]e f9d examples ( ^? geometrical =ms & almo/ _w-wide /raight l9es t give su* a rem>kable1 & z ,mr4 ,l[ell ma9ta9s1 'non-natural' "* to ! surface ( ,m>s1 b :i*1 z x seems to me1 ( !mselves af=d prima facie evid5ce ( a correspond+ simplicity & uni=mity 9 its int]nal /ructure4 ,yet we are n ourselves by any means devoid ( '/raight l9es' /ructurally produc$1 9 spite ( e ob/acle ( div]sity ( =m & texture1 ( s(tness & h>dness1 ( lam9ation or cry/allisation1 :i* are adv]se to su* developm5ts4 ,examples ( ^! are ! num]\s 'faults' :i* occur 9 ! h>d] rocks1 & :i* (t5 ext5d = great di/ances 9 almo/ p]fect /raight l9es4 ,9 our own c\ntry we h ! ,tyneside & ,crav5 faults 9 ! ,nor? ( ,engl&1 :i* are #cj miles long & (t5 #bj y>ds wide2 b ev5 m /rik+ is ! great ,clevel& ,dyke--a wall ( volcanic rock dipp+ slightly t[>ds ! s\?1 b sometimes be+ almo/ v]tical1 & /ret*+ across ! c\ntry1 ov] hill & dale1 9 an almo/ p]fect /raight l9e f a po9t on ! coa/ t5 miles nor? ( ,sc>bor\gh1 9 a we/-by-nor? direction1 pass+ ab\t two miles s\? ( ,/ockton & t]m9at+ ab\t six miles nor?-by-ea/ ( ,b>n>d ,ca/le1 a di/ance ( v ne>ly #fj miles4 ,! great fault betwe5 ! ,highl&s & ,l[l&s ( ,scotl& ext5ds across ! c\ntry f ,/onehav5 to ne> ,hel5sburgh1 a di/ance ( #abj miles2 & !re are v _m m ( less importance4 ,mu* m ext5sive are "s ( ! great cont95tal dislocations1 (t5 =m+ valleys ( consid]able wid? & l5g?4 ,! ,upp] ,rh9e fl[s 9 "o ( ^! great valleys ( subsid5ce = ab\t #ahj miles1 f ,mulhaus5 to ,frank=t1 9 a g5]ally /raight l9e1 ?\gh modifi$ by d5udation4 ,va/] /ill is ! valley ( ! ,jordan ?r\gh ! ,sea ( ,galilee to ! ,dead ,sea1 cont9u$ by ! ,wady ,arabah to ! ,gulf ( ,akaba1 believ$ to =m "o va/ geological depression or fracture ext5d+ 9 a /raight l9e = #djj miles4 ,?\s&s ( su* faults1 dykes1 or depressions exi/ 9 e "p ( ! _w1 all believ$ to be due to ! gradual %r9k+ ( ! heat$ int]ior to :i* ! solid cru/ has to accommodate itself1 & !y are especially int]e/+ & in/ructive = our pres5t purpose z %[+ ! t5d5cy ( su* fractures ( solid rock-mat]ial to ext5d to great l5g?s 9 /raight l9es1 not)/&+ ! extreme irregul>ity bo? 9 ! surface cont\r z well z 9 ! int]nal /ructures ( ! v>i$ deposits & =mations ?r\gh :i* !y pass4 ,probable ,orig9 ( ! ,surface-features ( ,m>s4 ,return+ n[ to ,m>s1 let u consid] ! probable c\rse ( ev5ts f ! po9t at :i* we left x4 ,! heat produc$ by impact & cond5sation w\ld be likely to release gases :i* _h be5 9 comb9ation ) "s ( ! solid matt]1 or p]haps be5 itself 9 a solid /ate due to int5se cold1 & ^!1 escap+ outw>ds to ! surface1 w\ld produce on a small scale a c]ta9 am\nt ( upheaval & volcanic di/urbance2 & z an out] cru/ rapidly =m$1 a numb] ( v5ts might rema9 z crat]s or crat]lets 9 a mod]ate /ate ( activity4 ,ow+ to ! comp>atively small =ce ( gravity1 ! out] cru/ w\ld become scoriace\s & m or less p]meat$ by ! gases1 :i* w\ld cont9ue to escape ?r\gh x1 & ?is w\ld facilitate ! cool+ ( ! :ole ( ! heat$ out] cru/1 & all[ x to become r d5sely compact$4 ,:5 ! great] portion ( ! gases _h ?us escap$ to ! out] surface & assi/$ to =m a scanty atmosph]e1 su* z n[ exi/s1 !re w\ld be no m int]nal di/urbance & ! cool+ ( ! heat$ out] coat+ w\ld /eadily progress1 result+ at la/ 9 a slightly heat$1 & lat] 9 a cold lay] ( mod]ate ?ickness & great g5]al uni=mity4 ,ow+ to ! abs5ce ( ra9 & riv]s1 d5udation su* z we exp]i5ce w\ld be unkn[n1 ?\gh ! sup]ficial scoriace\s cru/ might be p>tially brok5 up by expansion & contraction1 & suff] a c]ta9 am\nt ( atmosph]ic erosion4 ,! f9al result ( ?is mode ( aggregation w\ld be1 t ! planet w\ld consi/ ( an out] lay] ( mod]ate ?ickness z comp>$ ) ! c5tral mass1 :i* out] lay] w\ld h cool$ f a highly heat$ /ate to a temp]ature consid]ably bel[ ! freez+-po9t1 & ?is w\ld h be5 all ! "t contract+ ^u a previ\sly cold1 & !re=e non-contract+ nucleus4 ,! result w\ld be t v e>ly 9 ! process great sup]ficial t5sions w\ld be produc$1 :i* c\ld only be reliev$ by cracks or fissures1 :i* w\ld initiate at po9ts ( weakness--probably at ! crat]lets already ref]r$ to--f :i* !y w\ld radiate 9 sev]al directions4 ,ea* crack ?us =m$ ne> ! surface w\ld1 z cool+ progress$1 develop 9 l5g? & dep?2 & ow+ to ! g5]al uni=mity ( ! mat]ial1 & possibly "s am\nt ( cry/all9e /ructure due to sl[ & cont9u\s cool+ d[n to a v l[ temp]ature1 ! cracks w\ld t5d to run on 9 /raight l9es & to ext5d v]tically d[nw>ds1 :i* two circum/ances w\ld necess>ily result 9 _! =m+ portions ( 'great circles' on ! planet's surface--! two great facts :i* ,mr4 ,l[ell appeals to z be+ especially 'non-natural4' ,symmetry ( ,basaltic ,columns4 ,we h h[ev] "o q natural fact on our e>? :i* s]ves to illu/rate "o ( ^! two features1 ! direction ( ! d[nw>d fissure4 ,?is is1 ! comp>atively common ph5om5on ( basaltic columns & ',giant's ,causeways4' ,! wond]ful regul>ity ( ^!1 & especially ! n unfrequ5t upright pill>s 9 s]ri$ ranks1 z 9 ! palisades ( ! ,hudson riv]1 mu/ h always impress$ obs]v]s ) _! appe>ance ( artificiality4 ,yet !y are und\bt$ly ! result ( ! v sl[ cool+ & contraction ( melt$ rocks "u compression by /rata bel[ & above !m1 s t1 :5 once solidifi$1 ! mass 0 held 9 position & ! t5sion produc$ by contraction c\ld only be reliev$ by num]\s v small cracks at %ort di/ances f ea* o!r 9 e direction1 result+ 9 five1 six1 or sev5-sid$ polygons1 ) sides only a few in*es long4 ,?is contraction began ( c\rse at ! coole/ surface1 g5]ally ! upp] "o2 & obs]vation ( ^! columns 9 v>i\s positions has e/abli%$ ! rule t _! direction l5g?ways is always at "r angles to ! cool+ surface1 & ?us1 :5ev] ?is surface 0 horizontal1 ! columns became almo/ exactly v]tical4 ,h[ ?is applies to ,m>s4 ,"o ( ! features ( ! surface ( ,m>s t ,mr4 ,l[ell describes ) mu* confid5ce is1 t x is wond]fully uni=m & level1 :i* ( c\rse x w\ld be if x _h once be5 9 a liquid or pla/ic /ate1 & n mu* di/urb$ s9ce by volcanic or o!r int]nal movem5ts4 ,! result w\ld be t cracks =m$ by contraction ( ! h>d5$ out] cru/ w\ld be v]tical2 &1 9 a g5]ally uni=m mat]ial at a v uni=m temp]ature1 ^! cracks w\ld cont9ue almo/ indef9itely 9 /raight l9es4 ,! h>d5$ & contract+ surface be+ free to move lat]ally on acc\nt ( !re be+ a m heat$ & pla/ic lay] bel[ x1 ! cracks once initiat$ above w\ld cont9ually wid5 at ! surface z !y p5etrat$ deep] & deep] into ! slightly heat$ sub/ratum4 ,n[1 z basalt beg9s to s(t5 at ab\t #adjj ,f4 & ! surface ( ,m>s has cool$ to at lea/ ! freez+-po9t--p]haps v mu* bel[ x--! contraction w\ld be s great t if ! fissures produc$ 7 #ejj miles ap>t !y might be ?ree miles wide at ! surface1 &1 if only #ajj miles ap>t1 !n ab\t two-?irds ( a mile wide4#ae ,b z ! production ( ! fissures might h occupi$ p]haps millions ( ye>s1 a consid]able am\nt ( atmosph]ic d5udation w\ld result1 h[ev] sl[ly x act$4 ,expansion & contraction w\ld we> away ! edges & sides ( ! fissures1 fill up _m ( !m ) ! debris1 & wid5 !m at ! surfaces to p]haps d\ble _! orig9al size4#af ,footnote #ae3 ,! coeffici5t ( contraction ( basalt is #j4jjjjjf = #a ,f41 :i* w\ld lead to ! results giv5 "h4 ,footnote #af3 ,mr4 ,w4,h4 ,pick]+ obs]v$ cl\ds on ,m>s #ae miles high2 ^! are ! 'projections' se5 on ! t]m9ator :5 ! planet is p>tially illum9at$4 ,!y 7 at fir/ ?\ght to be m\nta9s2 b dur+ ! opposition ( #ahid1 m ?an #djj ( !m 7 se5 at ,flag/aff dur+ n9e mon?s' obs]vation4 ,usually !y are ( r>e occurr5ce4 ,!y are se5 to *ange 9 =m & position f day to day1 & ,mr4 ,l[ell is /rongly ( op9ion t !y are du/-/orms1 n :at we t]m cl\ds4 ,!y 7 mo/ly ab\t #ac miles high1 indicat+ consid]able a]ial di/urbance on ! planet1 & !re=e capable ( produc+ proportional surface d5udation4 ,sugge/$ ,explanation ( ! ',oases4' ,! num]\s r\nd dots se5 ^u ! 'canals1' & especially at po9ts f :i* sev]al canals radiate & :]e !y int]sect--t]m$ 'oases' by ,mr4 ,l[ell & 'crat]lets' by ,mr4 ,pick]+ may be expla9$ 9 two ways4 ,^? f :i* sev]al canals radiate may be true crat]s f :i* ! gases imprison$ 9 ! heat$ surface lay]s h gradually escap$4 ,!y w\ld be situat$ at po9ts ( weakness 9 ! cru/1 & become c5tres f :i* cracks w\ld />t dur+ contraction4 ,^? dots :i* occur at ! cross+ ( two /raight canals or cracks may h orig9at$ f ! fact t at su* int]sections !re w\ld be f\r %>ply-project+ angles1 :i*1 be+ expos$ to ! influ5ce ( alt]nate heat & cold 7dur+ day & night7 on ! two opposite surfaces1 w\ld inevitably 9 "t become fractur$ & crumbl$ away1 result+ 9 ! =mation ( a r\ghly circul> *asm :i* w\ld become p>tly fill$ up by ! debris4 ,^? =m$ by cracks radiat+ f crat]lets w\ld also be subject to ! same process ( r\nd+ (f to an ev5 great] ext5t2 & ?us w\ld be produc$ ! 'oases' ( v>i\s sizes up to #ej miles or m 9 diamet] record$ by ,mr4 ,l[ell & o!r obs]v]s4 ,probable ,function ( ! ,great ,fissures4 ,mr4 ,pick]+1 z we h se51 supposes t ^! fissures give out ! gases :i*1 ov]fl[+ on ea* side1 fav\r ! gr[? ( ! suppos$ vegetation :i* r5d]s ! c\rse ( ! canals visible1 & ?is no d\bt may h be5 ! case dur+ ! remote p]iods :5 ^! cracks gave access to ! heat$ portions ( ! surface lay]4 ,b x seems m probable t ,m>s has n[ cool$ d[n to ! almo/ uni=m mean temp]ature x d]ives f sol> heat1 & t ! fissures--n[ = ! mo/ "p broad %all[ valleys--s]ve m]ely z *annels along :i* ! liquids & heavy gases d]iv$ f ! melt+ ( ! pol> sn[s naturally fl[1 &1 ow+ to _! ne>ly level surfaces1 ov]fl[ to a c]ta9 di/ance on ea* side ( !m4 ,sugge/$ ,orig9 ( ! ,blue ,pat*es4 ,^! heavy gases1 ma9ly p]haps1 z has be5 (t5 sugge/$1 c>bon-dioxide1 w\ld1 :5 9 l>ge quantity & ( consid]able dep?1 reflect a good deal ( light1 &1 be+ almo/ inevitably du/-lad51 might produce t blue t+e adjac5t to ! melt+ sn[-caps :i* ,mr4 ,l[ell has errone\sly assum$ to be itself a pro( ( ! pres5ce ( liquid wat]4 ,j z ! blue ( our sky is und\bt$ly due to reflection f ! ultra-m9ute du/ p>ticles 9 our high] atmosph]e1 simil> p>ticles br\ght d[n by ! 'sn[' f ! high] ,m>tian atmosph]e might produce ! blue t+e 9 ! great volumes ( heavy gas produc$ by its evaporation or liquefaction4 ,x may be not$ t ,mr4 ,l[ell objects to ! c>bon-dioxide !ory ( ! =mation ( ! sn[-caps1 t ?is gas at l[ pressures does n liquefy1 b passes at once f ! solid to ! gase\s /ate1 & t only wat] rema9s liquid suffici5tly long to produce ! blue col\r' :i* plays s l>ge a "p 9 8 argum5t = ! mild climate ess5tial = an inhabit$ planet4 ,b ?is argum5t1 z ,i h already %[n1 is valueless4 ,= only v deep wat] c possibly %[ a blue col\r by reflect$ light1 :ile a du/-lad5 atmosph]e--especially ) a lay] ( v d5se gas at ! bottom ( x1 z w\ld be ! case ) ! newly evaporat$ c>bon-dioxide f ! dim9i%+ sn[-cap --w\ld provide ! v conditions likely to produce ?is blue t+e ( col\r4 ,x may be consid]$ a support to ?is view t c>bonic-acid gas becomes liquid at--#adj ,f4 & solid at--#afb ,f41 temp]atures f> high] ?an we %\ld expect to prevail 9 ! pol> & nor? temp]ate regions ( ,m>s dur+ a consid]able "p ( ! ye>1 b su* z might be rea*$ !re dur+ ! summ] sol/ice :5 ! sn[s' s rapidly disappe>1 to be re-=m$ a few mon?s lat]4 ,! ,d\ble ,canals4 ,! curi\s ph5om5a ( ! 'd\ble canals' are und\bt$ly ! mo/ difficult to expla9 satisfactorily on any !ory t has yet be5 sugge/$4 ,!y v>y 9 di/ance ap>t f ab\t #ajj to #djj miles4 ,9 _m cases !y appe> p]fectly p>allel1 & ,mr4 ,l[ell gives u ! impression t !y are almo/ always s4 ,b 8 maps %[1 9 "s cases1 decid$ diff]5ces ( wid? at ! two extremities1 indicat+ consid]able want ( p>allelism4 ,a few ( ! curv$ canals are also d\ble4 ,!re is "o draw+ 9 ,mr4 ,l[ell's book 7p4 #bai7 ( ! m\?s1 or />t+ po9ts1 ( ! ,euphrates & ,phison1 two widely sep>at$ d\ble canals div]g+ at an angle ( ab\t #dj f ! same two oases1 s t ! two inn] canals cross ea* o!r4 ,n[ ?is sugge/s two wide b&s ( weakness 9 ! planet's cru/ radiat+ probably f )9 ! d>k tract call$ ! ',m>e ,ic>ium1' & t "s widespread volcanic outbur/ initiat$ div]g+ cracks on ei!r side ( ^! b&s4 ,some?+ ( ?is k9d may h be5 ! cause ( mo/ ( ! d\ble canals1 or !y may h be5 />t$ f two or m crat]lets n f> ap>t1 ! direction be+ at fir/ decid$ by "s local peculi>ity ( /ructure2 & :]e begun cont9u+ 9 /raight l9es ow+ to homog5eity or uni=m d5sity ( mat]ial4 ,?is is v vague1 b ! ph5om5a are s rem>kable1 & s v imp]fectly kn[n at pres5t1 t no?+ b sugge/ion c be attempt$4 ,conclud+ ,rem>ks on ! ',canals4' ,9 ?is some:at detail$ exposition ( a possible1 &1 ,i hope1 a probable explanation ( ! surface-features ( ,m>s1 ,i h endeav\r$ to be guid$ by kn[n facts or accept$ !ories bo? a/ronomical & geological4 ,i ?9k ,i may claim to h %[n t !re are "s analog\s features ( t]re/rial rock-/ructure to s]ve z guides t[>ds a natural & intelligible explanation ( ! /range geometric m>k+s discov]$ dur+ ! la/ ?irty ye>s1 & :i* h rais$ ?is planet f comp>ative obscurity into a position ( ! v fir/ rank bo? 9 a/ronomical & popul> int]e/4 ,?is wide-spread int]e/ is v l>gely due to ,mr4 ,l[ell's devotion to its /udy1 bo? 9 seek+ out s admirable a position z reg>ds altitude & climate1 & 9 e/abli%+ !re a fir/-class obs]vatory2 & also 9 br++ 8 discov]ies be=e ! public 9 connection ) a !ory s />tl+ z to compel att5tion4 ,i v5ture to ?9k t 8 m]it z "o ( our fir/ a/ronomical obs]v]s w 9 no way be dim9i%$ by ! rejection ( 8 !ory1 & ! sub/itution ( "o m 9 accordance ) ! actually obs]v$ facts4 ,,app5dix4 ,a ,sugge/$ ,exp]im5t to ,illu/rate ! ',canals' ( ,m>s4 ,if my explanation ( ! 'canals' %\ld be sub/antially correct--t is1 if !y 7 produc$ by ! contraction ( a heat$ outw>d cru/ ^u a cold1 & !re=e non-contract+ int]ior1 ! result ( su* a condition might be %[n exp]im5tally4 ,sev]al bak$ clay balls might be =m$ to s]ve z cores1 say ( #h to #aj in*es 9 diamet]4 ,^! be+ fix$ )9 m\lds ( say half an in* to an in* great] diamet]1 ! out] lay] w\ld be =m$ by p\r+ 9 "s suitable heat$ liquid mat]ial1 & releas+ x f ! m\ld z soon z consolidation occurs1 s t x may cool rapidly f ! outside4 ,"s k9ds ( impure glass1 or ! brittle metals bismu? or antimony or alloys ( ^! might be us$1 9 ord] to see :at =m ! result+ fractures w\ld take4 ,x w\ld be well to h sev]al duplicates ( ea* ball1 &1 z soon z t5sion ?r\gh contraction manife/s itself1 to try ! effect ( fir+ v small *>ges ( small %ot to asc]ta9 :e!r su* impacts w\ld />t radiat+ fractures4 ,:5 tak5 f ! m\lds1 ! balls %\ld be susp5d$ 9 a slight curr5t ( air1 & kept rotat+1 to reproduce ! planet>y condition z ne>ly z possible4 ,! exact size & mat]ial ( ! cores1 ! ?ickness ( ! heat$ out] cru/1 ! mat]ial be/ suit$ to %[ fracture by contraction1 & ! details ( _! treatm5t1 might be modifi$ 9 v>i\s ways z sugge/$ by ! results fir/ obta9$4 ,su* a s]ies ( exp]im5ts w\ld probably ?r[ fur!r light on ! physical conditions :i* h produc$ ! gigantic sy/em ( fissures or *annels we see ^u ! surface ( ,m>s1 ?\gh x w\ld n1 ( c\rse1 prove t su* conditions actually exi/$ !re4 ,9 su* a speculative matt] we c only be guid$ by probabilities1 bas$ ^u :atev] evid5ce is available4 ,,*apt] ,,viii4 ,,summ>y ,,& ,,conclusion4 ,?is little volume has necess>ily t\*$ ^u a great v>iety ( subjects1 9 ord] to deal 9 a tol]ably complete mann] ) ! v extraord9>y !ories by :i* ,mr4 ,l[ell attempts to expla9 ! unique features ( ! surface ( ! planet1 :i*1 by long-cont9u$ /udy1 he has almo/ made 8 own4 ,x may !re=e be well to sum up ! ma9 po9ts ( ! argum5ts aga9/ 8 view1 introduc+ a few o!r facts & consid]ations :i* greatly /r5g!n my argum5t4 ,! "o great feature ( ,m>s :i* l$ ,mr4 ,l[ell to adopt ! view ( its be+ inhabit$ by a race ( highly intellig5t be+s1 &1 ) ev]-increas+ discov]y to uphold ?is !ory to ! pres5t "t1 is und\bt$ly t ( ! s-call$ 'canals'--_! /raightness1 _! enorm\s l5g?1 _! great abundance1 & _! ext5sion ov] ! planet's :ole surface f "o pol> sn[-cap to ! o!r4 ,! v imm5sity ( ?is sy/em1 & its con/ant gr[? & ext5sion dur+ fifte5 ye>s ( p]si/5t obs]vation1 h s completely tak5 possession ( 8 m9d1 t1 aft] a v ha/y glance at analog\s facts & possibilities1 he has decl>$ !m to be 'non-natural'-- !re=e to be works ( art--!re=e to necessitate ! pres5ce ( highly intellig5t be+s :o h design$ & con/ruct$ !m4 ,?is idea has col\r$ or gov]n$ all 8 writ+s on ! subject4 ,! innum]able difficulties :i* x raises h be5 ei!r ignor$1 or bru%$ aside on ! flimsie/ evid5ce4 ,z examples1 he nev] ev5 discusses ! totally inadequate wat]-supply = su* worldwide irrigation1 or ! extreme irrationality ( con/ruct+ s va/ a canal-sy/em ! wa/e f :i*1 by evaporation1 :5 expos$ to su* des]t conditions z he himself describes1 w\ld use up t5 times ! probable supply4 ,aga91 he urges ! 'purpose' display$ 9 ^! 'canals4' ,_! be+ all s /raight1 all describ+ great circles ( ! 'sph]e1' all be+ s evid5tly arrang$ 7z he ?9ks7 ei!r to c>ry wat] to "s 'oasis' #bjjj miles away1 or to rea* "s arid region f> ov] ! equator 9 ! opposite hemisph]e6 ,b he nev] consid]s ! difficulties ?is implies4 ,ev]y:]e ^! canals run = ?\s&s ( miles across wat]less des]ts1 =m+ a sy/em & indicat+ a purpose1 ! wond]ful p]fection ( :i* he is nev] tir$ ( dwell+ ^u 7b :i* ,i myself c n[h]e p]ceive74 ,yet he nev] ev5 attempts to expla9 h[ ! ,m>tians c\ld h liv$ be=e ?is great sy/em 0 plann$ & execut$1 or :y !y did n fir/ utilise & r5d] f]tile ! belt ( l& adjac5t to ! limits ( ! pol> sn[s--:y ! me?od ( irrigation did n1 z ) all human arts1 beg9 gradually1 at home1 ) t]races & *annels to irrigate ! l& close to ! s\rce ( ! wat]4 ,h[1 ) su* a des]t z he describes ?ree-f\r?s ( ,m>s to be1 did ! inhabitants ev] get to "k any?+ ( ! equatorial regions & its ne$s1 s z to />t "r away to supply ^? ne$s8 ,all ?is1 to my m9d1 is q oppos$ to ! idea ( _! be+ works ( art1 & altoge!r 9 fav\r ( _! be+ natural features ( a globe z peculi> 9 orig9 & int]nal /ructure z x is 9 its surface-features4 ,! explanation ,i h giv51 ?\gh ( c\rse hypo!tical1 is f\nd$ on kn[n cosmical & t]re/rial facts1 & is1 ,i sugge/1 f> m sci5tific z well z m satisfactory ?an ,mr4 ,l[ell's :olly unsupport$ speculation4 ,?is view ,i h expla9$ 9 "s detail 9 ! prec$+ *apt]4 ,mr4 ,l[ell nev] ev5 ref]s to ! important "q ( loss by evaporation 9 ^! enorm\s op5 canals1 or consid]s ! und\bt$ fact t ! only intellig5t & practical way to convey a limit$ quantity ( wat] su* great di/ances w\ld be by a sy/em ( wat]-tight & air-tight tubes laid "u ! gr\nd4 ,! m]e attempt to use op5 canals = su* a purpose %[s complete ignorance & /upidity 9 ^! alleg$ v sup]ior be+s2 :ile x is c]ta9 t1 long be=e half ( !m 7 complet$ _! failure to be ( any use w\ld h l$ any rational be+s to cease con/ruct+ !m4 ,he also fails to consid] ! difficulty1 t1 if ^! canals are necess>y = exi/5ce 9 ,m>s1 h[ did ! inhabitants ev] rea* a suffici5tly l>ge population ) surplus food & leisure enabl+ !m to rise f ! l[ condition ( savages to "o ( civilisation1 & ultimately to sci5tific k8 ,"h aga9 is a dilemma :i* is h>d to ov]come4 ,only a d5se population ) ample means ( subsi/5ce c\ld possibly h con/ruct$ su* gigantic works2 b1 giv5 ^! two conditions1 no adequate motive exi/$ = ! conception & execution ( !m--ev5 if !y 7 likely to be ( any use1 :i* ,i h %[n !y c\ld n be4 ,fur!r ,consid]ations on ! ,climate ( ,m>s4 ,recurr+ n[ to ! "q ( climate1 :i* is all-important1 ,mr4 ,l[ell nev] ev5 discusses ! ess5tial po9t--! temp]ature t mu/ necess>ily result f an atmosph]ic envelope "o-twelf? 7or at mo/ "o-sev5?7 ! d5sity ( our own2 9 ei!r case correspond+ to an altitude f> great] ?an t ( our highe/ m\nta9s4#ag ,surely ?is ph5om5on1 ev]y:]e manife/$ on ! e>? ev5 "u ! equator1 ( a regul> decrease ( temp]ature ) altitude1 ! only cause ( :i* is a less d5se atmosph]e1 %\ld h be5 fairly grappl$ )1 & "s attempt made to %[ :y x %\ld n apply to ,m>s1 except ! weak rem>k t on a level surface x w n h ! same effect z on expos$ m\nta9 heights4 ,b x does h ! same effect1 or v ne>ly s1 on our l(ty plateaux (t5 hundr$s ( miles 9 ext5t1 9 proportion to _! altitude4 ,quito1 at #icej ft4 above ! sea1 has a mean temp]ature ( ab\t #eg ,f41 giv+ a l[]+ ( #bc f t ( ,manaos at ! m\? ( ! ,rio ,negro4 ,?is is ab\t a degree = ea* #djj feet1 :ile ! g5]al fall = isolat$ m\nta9s is ab\t "o degree 9 #cdj feet accord+ to ,humboldt1 :o notes ! above diff]5ce betwe5 ! rate ( cool+ = altitude ( ! pla9s--or m usually %elt]$ valleys 9 :i* ! t[ns are situat$--& ! expos$ m\nta9 sides4 ,x w be se5 t ?is l[] rate w\ld br+ ! temp]ature ( ,m>s at ! equator d[n to #bj ,f4 bel[ ! freez+ po9t ( wat] f ?is cause alone4 ,footnote #ag3 ,a f\r in*es b>omet] is equival5t to a height ( #dj1jjj feet above sea-level ) u4 ,b all enquir]s h admitt$1 t if conditions z to atmosph]e 7 ! same z on ! e>?1 its great] di/ance f ! sun w\ld r$uce ! temp]ature to-#ca ,f41 equal to #fc bel[ ! freez+ po9t4 ,x is !re=e c]ta9 t ! comb9$ effect ( bo? causes mu/ br+ ! temp]ature ( ,m>s d[n to at lea/ #gj or #hj;bel[ ! freez+ po9t4 ,! cause ( ?is absolute dep5d5ce ( t]re/rial temp]atures ^u d5sity ( ! air-envelope is seldom discuss$ 9 text-books ei!r ( geography or ( physics1 & !re seems to be /ill "s unc]ta9ty ab\t x4 ,"s impute x :olly to ! ?9n] air be+ unable to absorb & reta9 s mu* heat z t :i* is m d5se2 b if ?is 7 ! case ! soil at great altitudes n hav+ s mu* ( its heat tak5 up by ! air %\ld be w>m] ?an bel[1 s9ce x und\bt$ly receives m heat ow+ to ! great] transp>5cy ( ! air above x2 b x c]ta9ly does n become w>m]4 ,! m correct view seems to be t ! loss ( heat by radiation is increas$ s mu* ?r\gh ! r>ity ( ! air above x z to m ?an c\nt]balance ! increas$ insolation1 s t ?\gh ! surface ( ! e>? at a giv5 altitude may receive #aj p] c5t4 m direct sun-heat x loses by direct radiation1 comb9$ ) dim9i%$ air & cl\d-radiation1 p]haps #bj or #be p] c5t4 m1 :5ce !re is a resultant cool+ effect ( #aj or #ae p] c5t4 ,?is acts by day z well z by night1 s t ! great] heat receiv$ at high altitudes does n w>m ! soil s mu* z a less am\nt ( heat ) a d5s] atmosph]e4 ,?is effect is fur!r int5sifi$ by ! fact t a less d5se _c absorb & transmit s mu* heat z a m d5se atmosph]e4 ,"h !n we h an absolute law ( nature to be obs]v$ op]at+ ev]y:]e on ! e>?1 & ! mode ( action ( :i* is fairly well und]/ood4 ,?is law is1 t r$uc$ atmosph]ic pressure increases radiation1 or loss ( heat1 m rapidly ?an x increases insolation or ga9 ( heat1 s t ! result is always a consid]able l[]+ ( temp]ature4 ,:at ?is l[]+ is c be se5 9 ! univ]sal fact1 t ev5 )9 ! tropics p]petual sn[ cov]s ! high] m\nta9 summits1 :ile on ! high pla9s ( ! ,&es1 at #ae1jjj or #af1jjj feet altitude1 :]e !re is v little or no sn[1 travell]s are (t5 froz5 to dea? :5 delay$ by /orms2 yet at ?is elevation ! atmosph]e has mu* m ?an d\ble ! d5sity ( t ( ,m>s6 ,! error 9 ,mr4 ,l[ell's argum5t is1 t he claims = ! scanty atmosph]e ( ,m>s t x all[s m sun-heat to rea* ! surface2 b he omits to take acc\nt ( ! enorm\sly increas$ loss ( heat by direct radiation1 z well z by ! dim9ution ( air-radiation1 :i* toge!r necess>ily produce a great r$uction ( temp]ature4 ,x is ?is great pr9ciple ( ! prepot5cy ( radiation ov] absorption ) a dim9i%+ atmosph]e t expla9s ! excessively l[ temp]ature ( ! moon's surface1 a fact :i* also s]ves to indicate a v l[ temp]ature = ,m>s1 z ,i h %[n 9 ,*apt] ,,vi4 ,^! two indep5d5t argum5ts--f alp9e temp]atures & f ^? ( ! moon--support & en=ce ea* o!r1 & af=d a conclusive pro( 7z aga9/ any?+ advanc$ by ,mr4 ,l[ell7 t ! temp]ature ( ,m>s mu/ be f> too l[ to support animal life4 ,a ?ird indep5d5t argum5t lead+ to ! same result is ,dr4 ,john/one ,/oney's pro( t aque\s vap\r _c exi/ on ,m>s2 & ?is fact ,mr4 ,l[ell does n attempt to controv]t4 ,to put ! :ole case 9 ! fewe/ possible words3 ,all physici/s are agre$ t1 ow+ to ! di/ance ( ,m>s f ! sun1 x w\ld h a mean temp]ature ( ab\t-#ce ,f4 7 #def ,f4 abs47 ev5 if x _h an atmosph]e z d5se z ours4 7#b7 ,b ! v l[ temp]atures on ! e>? "u ! equator1 at a height :]e ! b>omet] /&s at ab\t ?ree times z high z on ,m>s1 proves1 t f scant9ess ( atmosph]e alone ,m>s _c possibly h a temp]ature z high z ! freez+ po9t ( wat]2 & ?is pro( is support$ by ,langley's det]m9ation ( ! l[ maximum temp]ature ( ! full moon4 ,! comb9ation ( ^! two results mu/ br+ d[n ! temp]ature ( ,m>s to a degree :olly incompatible ) ! exi/5ce ( animal life4 7#c7 ,! q indep5d5t pro( t wat]-vap\r _c exi/ on ,m>s1 & t !re=e1 ! fir/ ess5tial ( organic life--wat]--is non-exi/5t4 ,! conclusion f ^! ?ree indep5d5t pro(s1 :i* en=ce ea* o!r 9 ! multiple ratio ( _! respective weights1 is !re=e irresi/ible--t animal life1 especially 9 its high] =ms1 _c exi/ on ! planet4 ,m>s1 !re=e1 is n only un9habit$ by intellig5t be+s su* z ,mr4 ,l[ell po/ulates1 b is absolutely ,,un9habitable4