,transcrib]'s ,notes ,obvi\s typographical errors h be5 sil5tly correct$4 ,v>iations 9 hyph5ation h be5 /&>dis$ b all o!r spell+ & punctuation rema9s un*ang$4 ,italics are repres5t$ ?us italic1 bold ?us bold & sup]scripts ?us yen4 ,,worlds ,,9 ,,! ,,mak+ ,,! ,,evolution ,,( ,,! ,,univ]se ,,by ,,svante ,,arrh5ius ,,director ,,( ,,! ,,physico-,,*emical ,,nobel ,,in/itute1 ,,/ockholm ,,translat$ ,,by ,,dr4 ,h4 ,,borns ,,illu/rat$ colophon ,,new ,,york ,,& ,,london ,,h>p] ,,bro!rs ,,publi%]s ,,mcmviii ,copyright1 #aijh1 by ,,h>p] ,,bro!rs4 ,all rights res]v$4 ,publi%$ ,m>*1 #aijh4 ,,table ,,( ,,cont5ts ,i4 ,,volcanic ,,ph5om5a ,,& ,,e>?quakes #a ,de/ruction caus$ by volcanism & by e>?quakes4--,diff]5t k9ds ( volcanoes4--,vesuvius4--,products ( eruption4--,volcanic activity dim9i%+4--,/ructure ( volcanoes4--,geographical di/ribution ( volcanoes4--,temp]ature 9 ! int]ior ( ! e>?4--,significance ( wat] = volcanism4--,composition ( ! e>?'s int]ior4--,geographical di/ribution ( e>?quakes4--,fissures 9 ! e>?'s cru/4--,gr\ps ( e>?quakes4--,waves 9 ! sea & 9 ! air accompany+ e>?quakes4--,_! connection ) volcanism4--,sy/ems ( fissures4--,seismograms4 ,,ii4 ,,! ,,cele/ial ,,bodies1 ,,9 ,,p>ticul> ,,! ,,e>?1 ,,z ,,abodes ,,( ,,liv+ ,,be+s #ci ,manifold "* ( ! worlds4--,! e>? probably at fir/ a ball ( gases4--,=mation ( ! e>? cru/ & its rapid cool+4--,balance betwe5 heat receiv$ & heat lo/ by radiation4--,life already exi/+ on ! e>? = a milli>d ( ye>s4--,! wa/e ( sol> heat4--,temp]ature & habitability ( ! planets4--,heat-pres]v+ influ5ce ( ! atmosph]e4--,significance ( c>bon dioxide 9 ! atmosph]e4--,w>m & cold geological ages4--,fluctuations 9 ! p]c5tage ( c>bon dioxide ( ! air4--,combu/ion1 decay1 & gr[?4--,atmosph]ic oxyg54--,vegetable life m anci5t ?an animal life4--,! atmosph]es ( planets4--,*ances ( an improvem5t 9 ! climate4 ,,iii4 ,,radiation ,,& ,,con/itution ,,( ,,! ,,sun #fd ,/ability ( ! sol> sy/em4--,losses & possible ga9s ( heat by ! sun4--,!ses ( ,may] & ( ,helmholtz4--,temp]atures ( ! :ite1 yell[1 & r$di% />s1 & ( ! sun4--,sun-spots & sun facul4--,prom95ces4--,spectra ( ! p>ts ( ! sun4--,temp]ature ( ! sun4--,! int]ior ( ! sun4--,its composition accord+ to ! me*anical !ory ( heat4--,! losses ( heat by ! sun probably cov]$ by ! enorm\s sol> en]gy4 ,,iv4 ,,! ,,radiation ,,pressure #id ,newton's law ( gravitation4--,kepl]'s obs]vation ( comets' tails4--,! !sis ( ,eul]4--,pro( ( ,maxwell4--,! radiation pressure4--,electric *>ges & cond5sation4--,comets' tails & radiation pressure4--,con/itu5ts & prop]ties ( comets' tails4--,weight ( ! sol> corona4--,loss & ga9 ( matt] by ! sun4--,nature ( meteorites4--,electric *>ge ( ! sun4--,electrons drawn into ! sun4--,magnetic prop]ties ( ! sun & appe>ance ( ! corona4--,con/itu5ts ( ! meteors4--,nebul & _! heat & light4 ,v4 ,,! ,,sol> ,,du/ ,,9 ,,! ,,atmosph]e4 ,,pol> ,,lights ,,& ,,! ,,v>iations ,,( ,,t]re/rial ,,magnetism #aah ,! supply ( du/ f ! sun r insignificant4--,pol>ization ( ! light ( ! sky4--,! upp] cl\ds4--,diff]5t k9ds ( auror4--,_! connection ) ! corona ( ! sun4--,pol> lights & sun-spots4--,p]iodicity ( pol> lights4--,pol> lights & magnetic di/urbances4--,velocity ( sol> du/4--,fixation ( atmosph]ic nitrog54--,! ,zodiacal ,light4 ,,vi4 ,,end ,,( ,,! ,,sun4--,,orig9 ,,( ,,nebul #adh ,! ext9ction ( ! sun4--,collision betwe5 two cele/ial bodies4--,! new /> 9 ,p]seus4--,=mation ( nebul4--,! appe>ance ( nebul4--,! nebul cat* w&]+ meteors & comets4--,! r+ nebula 9 ,lyra4--,v>iable />s4--,eta 9 ,argus4--,mira ,ceti4--,lyra & ,algol />s4--,evolution ( ! />s4 ,,vii4 ,,! ,,nebul> ,,& ,,! ,,sol> ,,/ates #aia ,! en]gy ( ! univ]se4--,! entropy ( ! univ]se4--,! entropy increases 9 ! suns1 b decreases 9 ! nebul4--,temp]ature & con/itution ( ! nebul4--,s*u/]'s calculations ( ! condition ( a cele/ial body consi/+ ( gases4--,action ( ! loss ( heat on nebul & on suns4--,developm5t ( a rotat+ nebula into a planet>y sy/em4--,! hypo!sis ( ,kant-,laplace4--,objections to x4--,! views ( ,*amb]l9 & ,m\lton4--,! radiation pressure balances ! effect ( ,newtonian gravitation4--,! emission ( gases f ! nebul balances ! wa/e ( heat *>act]i/ic to ! sol> sy/ems4 ,,viii4 ,,! ,,spread+ ,,( ,,life ,,?r\gh ,,! ,,univ]se #bab ,/ability ( ! species4--,!ory ( mutation4--,spontane\s g5]ation4--,ba?ybius4--,pansp]mia4--,! /&-po9ts ( ,ri*t]1 ,f]d9& ,cohn1 & ,"l ,kelv94--,! radiation pressure enables spores to escape4--,! effect ( /rong sunlight & ( cold on ! g]m9at+ p[]4--,transport ( spores ?r\gh ! atmosph]e into univ]sal space & ?r\gh x to o!r planets4--,g5]al conclusions4 ,,explanation ,,( ,,abbreviations1 ,,etc4 ,! temp]atures are /at$ 9 degrees c5tigrade 7 ,c471 ei!r on ! ,celsius scale1 on :i* ! freez+-po9t ( wat] is #j1 or on ! absolute scale1 ^: z]o lies #bgc degrees bel[ ! freez+-po9t ( wat]1 at -#bgc ,c4 ,! equival5t temp]atures on ! ,fahr5heit scale 7freez+-po9t ( wat] #cb ,f47 are add$ 9 brackets 7 ,f474 #a metre 7m47 #aj decimetres 7dm47 #ajj c5timetres 7cm47 #ajjj millimetres 7mm47 #c4bh ft42 #a kilometre 7km47 #ajjj metres 7m47 #j4fb miles2 #a mile #a4f kilometres 7km474 ,light travels 9 vacuo at ! rate ( #cjj1jjj km4 7ne>ly #bjj1jjj miles7 p] second4 ,,illu/rations ,,fig4 ,,page #a4 ,,vesuvius1 ,,z ,,se5 ,,f ,,! ,,isl& ,,( ,,nisida1 ,,9 ,,mod]ate ,,activity #b #b4 ,,eruption ,,( ,,vesuvius ,,9 #ahhb #d #c4 ,,eruption ,,( ,,vesuvius ,,9 #ahgb #f #d4 ,,photograph ,,( ,,vesuvius1 #aijf4 ,,*iefly ,,cl\ds ,,( ,,a%es #h #e4 ,,block ,,lava ,,on ,,mauna ,,loa #aj #f4 ,,! ,,excelsior ,,geys] ,,9 ,,yell[/one ,,p>k1 ,u4 ,s4 ,a4 ,,remnant ,,( ,,! ,,p[]ful ,,volcanic ,,activity ,,9 ,,! ,,t]ti>y ,,age #aa #g4 ,,mato ,,tepee ,,9 ,,wyom+1 ,u4 ,s4 ,a4 ,,typical ,,volcanic 8,,neck0 #ab #h4 ,,clefts ,,fill$ ,,) ,,lava ,,& ,,volcanic ,,cone ,,( ,,a%es1 ,,tor[heap ,,ca,,on1 ,,plateau ,,( ,,colorado #ac #i4 ,,! ,,kilauea ,,crat] ,,on ,,hawaii #ae #aj4 ,,*ief ,,e>?quake ,,c5tres1 ,,accord+ ,,to ,,! ,,briti% ,,association ,,committee #bb #aa4 ,,clefts ,,9 ,,val5tia ,,/reet1 ,,san ,,francisco1 ,,aft] ,,! ,,e>?quake ,,( #aijf #be #ab4 ,,s& ,,crat]s ,,& ,,fissures1 ,,produc$ ,,by ,,! ,,cor9? ,,e>?quake ,,( #ahfa4 ,,9 ,,! ,,wat]1 ,,bran*es ,,( ,,flood$ ,,trees #bg #ac4 ,,e>?quake ,,l9es ,,9 ,,l[] ,,au/ria #cj #ad4 ,,lib]ty ,,build+ ,,( ,,lel& ,,/an=d ,,junior ,,univ]sity1 ,,9 ,,cali=nia1 ,,aft] ,,! ,,e>?quake ,,( #aijf #cb #ae4 ,,e>?quake ,,l9es ,,9 ,,! ,,tyrrh5ian ,,depression #cd #af4 ,,seismogram ,,record$ ,,at ,,%ide1 ,,isle ,,( ,,wight1 ,,on ,,augu/ #ca1 #ahih #ce #ag4 ,,photograph ,,( ,,! ,,surface ,,( ,,! ,,moon1 ,,9 ,,! ,,vic9ity ,,( ,,! ,,crat] ,,( ,,cop]nicus #fb #ah4 ,,sun-,,spot ,,gr\p ,,& ,,granulation ,,( ,,! ,,sun #gd #ai4 ,,"p ,,( ,,! ,,sol> ,,spectrum ,,( ,,janu>y #c1 #ahgb #ge #bj4 ,,metallic ,,prom95ces ,,9 ,,vortex ,,motion #gf #ba4 ,,f\nta9-,,l ,,metallic ,,prom95ces #gf #bb4 ,,quiet ,,prom95ces ,,( ,,smoke-,,column ,,type #gg #bc4 ,,quiet ,,prom95ces1 ,,%ape ,,( ,a ,,tree #gg #bd4 ,,diagram ,,illu/rat+ ,,! ,,diff]5ces ,,9 ,,! ,,spectra ,,( ,,sun-,,spots ,,& ,,( ,,! ,,photosph]e #gh #be4 ,,spectrum ,,( ,a ,,sun-,,spot1 ,,! ,,c5tral ,,b& ,,betwe5 ,,! ,,two ,,portions ,,( ,,! ,,photosph]e ,,spectrum #gh #bf4 ,,! ,,great ,,sun-,,spot ,,( ,,octob] #i1 #aijc #gi #bg4 ,,! ,,great ,,sun-,,spot ,,( ,,octob] #i1 #aijc #hj #bh4 ,,! ,,great ,,sun-,,spot ,,( ,,octob] #i1 #aijc #ha #bi4 ,,! ,,great ,,sun-,,spot ,,( ,,octob] #i1 #aijc #hb #cj4 ,,photograph ,,( ,,! ,,sol> ,,corona ,,( #aijj #hc #ca4 ,,photograph ,,( ,,! ,,sol> ,,corona ,,( #ahgj #hd #cb4 ,,photograph ,,( ,,! ,,sol> ,,corona ,,( #ahih #he #cc4 ,,photograph ,,( ,,ro]dam',s ,,comet 7#ahic ,,ii471 ,,sugge/+ ,,sev]al ,,/rong ,,nuclei ,,9 ,,! ,,tail #ajj #cd4 ,,photograph ,,( ,,swift',s ,,comet 7#ahib ,i47 #aja #ce4 ,,donati',s ,,comet ,,at ,,its ,,greate/ ,,brilliancy ,,9 #aheh #ajb #cf4 ,,imitation ,,( ,,comets' ,,tails #ajd #cg4 ,,granul> ,,*ondrum ,,f ,,! ,,meteorite ,,( ,,sexes4 ,,enl>gem5t #a3gj #aji #ch4 ,,ar*-,,%ap$ ,,auror ,,borealis1 ,,obs]v$ ,,by ,,nord5skiold ,,dur+ ,,! ,,w9t]+ ,,( ,,! ,,vega ,,9 ,,b]+ ,,/rait #ahgi #abd #ci4 ,,aurora ,,borealis1 ,,) ,,radial ,,/ream]s #abe #dj4 ,,aurora ,,) ,,corona1 ,,obs]v$ ,,by ,,gyll5ski,,ld ,,on ,,spitzb]g51 #ahhc #abf #da4 ,,pol>-,,light ,,drap]ies1 ,,obs]v$ ,,9 ,,f9nm>k51 ,,nor!rn ,,norway #abg #db4 ,,curve ,,( ,,magnetic ,,decl9ation ,,at ,,kew1 ,,ne> ,,london1 ,,on ,,novemb] #ae ,,& #af1 #aije #ach #dc4 ,,curve ,,( ,,horizontal ,,int5sity ,,at ,,kew ,,on ,,novemb] #ae ,,& #af1 #aije #aci #dd4 ,,zodiacal ,,light ,,9 ,,! ,,tropics #adf #de4 ,,spectrum ,,( ,,nova ,,aurig1 #ahib #aed #df4 ,,diagram ,,indicat+ ,,! ,,consequ5ces ,,( ,a ,,collision ,,betwe5 ,,two ,,ext9ct ,,suns #aeg #dg4 ,,spiral ,,nebula ,,9 ,,! ,,canes ,,v5atici #aei #dh4 ,,spiral ,,nebula ,,9 ,,! ,,triangle #afa #di4 ,,! ,,great ,,nebula ,,9 ,,&rom$a #afc #ej4 ,,r+-,,%ap$ ,,nebula ,,9 ,,lyra #afd #ea4 ,,c5tral ,,portion ,,( ,,! ,,great ,,nebula ,,9 ,,orion #afe #eb4 ,,nebul> ,,/ri ,,9 ,,! ,,/>s ,,( ,,! ,,pleiades #afg #ec4 ,,nebul> ,,/ri ,,9 ,,! ,,swan #afi #ed4 ,,nebula ,,& ,,/> ,,rift ,,9 ,,! ,,swan1 ,,9 ,,! ,,milky ,,way #aga #ee4 ,,great ,,nebula ,,ne> ,,rho1 ,,9 ,,ophiu*us #agb #ef4 ,,/> ,,clu/] ,,9 ,,h]cules #agc #eg4 ,,/> ,,clu/] ,,9 ,,pegasus #age #eh4 ,,cone-,,%ap$ ,,/> ,,clu/] ,,9 ,,gem9i #agf #ei4 ,,comp>ison ,,( ,,spectra ,,( ,,/>s ,,( ,,classes #b1 #c1 #d #ahe #fj4 ,,comp>ison ,,( ,,spectra ,,( ,,/>s ,,( ,,classes #b1 #c1 #d #ahf ,,preface ,:51 m ?an six ye>s ago1 ,i 0 writ+ my ,treatise ( ,cosmic ,physics1 ,i f\nd myself confront$ ) great difficulties4 ,! views !n held w\ld n expla9 _m ph5om5a1 & !y fail$ 9 p>ticul> 9 cosmogonic problems4 ,! radiation pressure ( light1 :i* _h n1 s f>1 be5 he$$1 seem$ to give me ! key to ! elucidation ( _m obscure problems1 & ,i made a l>ge use ( ?is =ce 9 deal+ ) ^? ph5om5a 9 my treatise4 ,! explanations :i* ,i t5tatively (f]$ c\ld1 ( c\rse1 n claim to /& 9 all _! detail2 yet ! sci5tific _w receiv$ !m ) unusual int]e/ & b5evol5ce4 ,?us enc\rag$1 ,i tri$ to solve m ( ! num]\s important problems1 & 9 ! pres5t volume ,i h add$ "s fur!r sections to ! complex ( explanatory argum5ts conc]n+ ! evolution ( ! ,univ]se4 ,! f\ndation to ^! explanations 0 laid 9 a memoir :i* ,i pres5t$ to ! ,academy ( ,sci5ces at ,/ockholm 9 #aijj4 ,! memoir 0 soon aft]w>ds pr9t$ 9 ! ,physikalis*e ,zeits*rift1 & ! subject 0 fur!r develop$ 9 my ,treatise ( ,cosmic ,physics4 ,x w be object$1 & n )\t ju/ification1 t sci5tific !ses %\ld fir/ be discuss$ & approv$ ( 9 compet5t circles be=e !y are plac$ be=e ! public4 ,x _c be d5i$ t1 if ?is condition 7 to be fulfill$1 mo/ ( ! sugge/ions on cosmogony t h be5 publi%$ w\ld nev] h be5 s5t to ! compositors2 nor d ,i d5y t ! labor sp5t ^u _! publication might h be5 employ$ = "s bett] purpose4 ,b sev]al ye>s h elaps$ s9ce my fir/ attempts 9 ?is direction 7 communicat$ to sci5ti/s4 ,my sugge/ions h met ) a favorable reception1 & ,i h1 dur+ ^! ye>s1 _h ample opportunity c>efully to re-exam9e & to am5d my explanations4 ,i !re=e feel ju/ifi$ 9 submitt+ my views to a l>g] circle ( read]s4 ,! problem ( ! evolution ( ! ,univ]se has always excit$ ! pr(\nd int]e/ ( ?9k+ m54 ,& x w1 )\t d\bt1 rema9 ! mo/ em95t among all ! que/ions :i* d n h any direct1 practical be>+4 ,diff]5t ages h arriv$ at diff]5t solutions to ?is great problem4 ,ea* ( ^! solutions reflect$ ! /&-po9t ( ! natural philosoph]s ( its "t4 ,let me hope t ! consid]ations :i* ,i (f] w be wor?y ( ! gr& progress 9 physics & *emi/ry t has m>k$ ! close ( ! n9ete5? & ! op5+ ( ! tw5tie? c5tury4 ,be=e ! inde/ructibility ( en]gy 0 und]/ood1 cosmogony m]ely dealt ) ! "q h[ matt] c\ld h be5 arrang$ 9 su* a mann] z to give rise to ! actual worlds4 ,! mo/ rem>kable conception ( ?is k9d we f9d 9 ,h]s*el's sugge/ion ( ! evolution ( /ell> nebul1 & 9 ! !sis ( ,laplace conc]n+ ! =mation ( ! sol> sy/em out ( ! univ]sal nebula4 ,obs]vations m & m t5d to confirm ,h]s*el's view4 ,! !sis ( ,laplace1 = a long "t eulogiz$ z ! fl[] ( cosmogonic speculations1 has m & m _h to be modifi$4 ,if we attempt1 ) ,kant1 to conceive h[ wond]fully organiz$ /ell> sy/ems c\ld orig9ate f absolute *aos1 we %all h to admit t we are attack+ a problem :i* is insoluble 9 t %ape4 ,!re is a contradiction 9 ^? v attempts to expla9 ! orig9 ( ! ,univ]se 9 its totality1 z ,/allo#a emphasizes3 8,! only "q to :i* a s]ies ( ph5om5a gives legitimate rise relates to _! filiation & int]dep5d5ce40 ,i h1 !re=e1 only endeavor$ to %[ h[ nebul may orig9ate f suns & suns f nebul2 & ,i assume t ?is *ange has always be5 proce$+ z x is n[4 ,footnote #a3 ,/allo3 ,concepts & ,!ories ( ,mod]n ,physics4 ,london1 #aijj1 p4 #bgf4 ,! recognition ( ! inde/ructibility ( en]gy seem$ to acc5tuate ! difficulties ( ! cosmogonic problems4 ,! !ses ( ,may] & ( ,helmholtz1 on ! mann] 9 :i* ! ,sun repl5i%es its losses ( heat1 h _h to be ab&on$4 ,my explanation is bas$ ^u *emical reactions 9 ! int]ior ( ! ,sun 9 accordance ) ! second law ( !rmodynamics4 ,! !ory ( ! 8degradation0 ( en]gy appe>$ to introduce a /ill great] difficulty4 ,t !ory seems to lead to ! inevitable conclusion t ! ,univ]se is t5d+ t[>ds ! /ate :i* ,clausius has designat$ z 8,wrme ,tod0 7heat dea?71 :5 all ! en]gy ( ! ,univ]se w uni=mly be di/ribut$ ?r\gh space 9 ! %ape ( movem5ts ( ! smalle/ p>ticles4 ,t w\ld imply an absolutely inconceivable end ( ! developm5t ( ! ,univ]se4 ,! way out ( ?is difficulty :i* ,i propose comes to ?is3 ! en]gy is 8degrad$0 9 bodies :i* are 9 ! sol> /ate1 & ! en]gy is 8elevat$10 rais$ to a high] level1 9 bodies :i* are 9 ! nebul> /ate4 ,f9ally1 ,i wi% to t\* ^u "o cosmogonical "q :i* has rec5tly become m actual ?an x us$ to be4 ,"s k9d ( 8spontane\s g5]ation10 orig9ation ( life f inorganic matt]1 _h be5 acquiesc$ 94 ,b j z ! dreams ( a spontane\s g5]ation ( en]gy--i4e41 ( a p]petuum mobile--h be5 dispell$ by ! negative results ( all exp]im5ts 9 t direction1 j 9 ! same way we %all h to give up ! idea ( a spontane\s g5]ation ( life aft] all ! repeat$ disappo9tm5ts 9 ?is field ( inve/igation4 ,z ,helmholtz#b says1 9 8 popul> lecture on ! gr[? ( ! planet>y sy/em 7#ahga73 8,x seems to me a p]fectly j sci5tific proc$ure1 if we1 aft] ! failure ( all our attempts to produce organisms f lifeless matt]1 put ! "q1 :e!r life has _h a beg9n+ at all1 or :e!r x is n z old z matt]1 & :e!r se$s h n be5 c>ri$ f "o planet to ano!r & h develop$ ev]y:]e :]e !y h fall5 on a f]tile soil40 ,footnote #b3 ,helmholtz1 ,populr ,wiss5s*aftli*e ,vortrge4 ,brauns*weig1 #ahgf1 vol4 iii41 p4 #aja4 ,?is hypo!sis is call$ ! hypo!sis ( pansp]mia1 :i* ,i h modifi$ by comb9+ x ) ! !sis ( ! radiation pressure4 ,my guid+ pr9ciple 9 ?is exposition ( cosmogonic problems has be5 ! conviction t ! ,univ]se 9 its ess5ce has always be5 :at x is n[4 ,matt]1 en]gy1 & life h only v>i$ z to %ape & position 9 space4 ,,! ,,au?or4 ,,/ockholm1 ,decemb]1 #aijg4 ,,worlds ,,9 ,,! ,,mak+ ,i ,,volcanic ,,ph5om5a ,,& ,,e>?quakes ,! ,int]ior ( ! ,e>? ,! disa/]s :i* h rec5tly befall5 ! fl\ri%+ settlem5ts ne> ,vesuvius & 9 ,cali=nia h once m direct$ ! att5tion ( mank9d to ! t]rific =ces :i* manife/ !mselves by volcanic eruptions & e>?quakes4 ,! losses ( life :i* h be5 caus$ 9 ^! two la/ in/ances are1 h[ev]1 insignificant by comp>ison ) ^? :i* v>i\s previ\s cata/rophes ( ?is k9d h produc$4 ,! mo/ viol5t volcanic eruption ( mod]n times is no d\bt t ( ,augu/ #bf & #bg1 #ahhc1 by :i* two-?irds ( ! isl& ( ,krakatoa1 #cc squ>e kilometres 7#ac squ>e miles7 9 area1 situat$ 9 ! ,ea/ ,indian ,ar*ipelago1 7 bl[n into ! air4 ,al?\gh ?is isl& 0 itself un9habit$1 "s #dj1jjj p p]i%$ on t occasion1 *iefly by ! ocean wave :i* foll[$ ! eruption & :i* caus$ disa/r\s inundations 9 ! di/rict4 ,/ill m t]rible 0 ! de/ruction wr\ght by ! ,calabrian e>?quake ( ,febru>y & ,m>*1 #aghc1 :i* consi/$ ( sev]al e>?quake waves4 ,! l>ge t[n ( ,mess9a 0 de/roy$ on ,febru>y #e?1 & ! numb] ( p kill$ by ?is ev5t has be5 e/imat$ at #ajj1jjj4 ,! same region1 especially ,calabria1 has1 moreov]1 frequ5tly be5 visit$ by disa/r\s e>?quakes--aga9 9 #aije & #aijg4 ,ano!r cata/rophe ^u :i* hi/ory dwells1 ow+ to ! loss ( life 7n less ?an #ij1jjj71 0 ! de/ruction ( ! capital ( ,portugal on ,novemb] #a1 #agee4 ,two-?irds ( ! human lives :i* ?is e>?quake claim$ 7 de/roy$ by a wave #e m4 9 height ru%+ 9 f ! sea4 ,illu/ration3 ,fig4 #a4--,vesuvius1 z se5 f ! ,isl& ( ,nisida1 9 mod]ate activity ,vesuvius is und\bt$ly ! be/ /udi$ ( all volcanoes4 ,dur+ ! spl5dor ( ,rome ?is m\nta9 0 q peaceful--kn[n z an ext9ct volcanic cone s f> z hi/ory c\ld be trac$ back4 ,on ! extraord9>ily f]tile soil ab\t x _h aris5 big colonies ( su* weal? t ! di/rict 0 call$ ,great ,greece 7,grcia ,magna74 ,!n came1 9 ! ye> #gi ,a4,d41 ! deva/at+ eruption :i* de/roy$1 among o!rs1 ! t[ns ( ,h]culaneum & ,pompeii4 ,! volumes ( gas1 ru%+ =? ) extreme viol5ce f ! int]ior ( ! e>?1 pu%$ aside a l>ge "p ( ! volcanic cone ^: remnant is n[ call$ ,monte ,somma1 & ! fall+ masses ( a%es1 mix$ ) /reams ( lava1 built up ! new ,vesuvius4 ,?is m\nta9 has repeat$ly *ang$ its appe>ance dur+ lat] eruptions1 & 0 provid$ ) a new cone ( a%es 9 ! ye> #aijf4 ,! outbreak ( ! ye> #gi 0 succe$$ by new eruptions 9 ! ye>s #bjc1 #dgb1 #eab1 #fhe1 #iic1 #ajcf1 #aaci1 #aejj1 #afca1 & #affj1 at q irregul> int]vals4 ,s9ce t "t ,vesuvius has be5 9 almo/ un9t]rupt$ activity1 mo/ly1 h[ev]1 ( a h>mless k9d1 s t only ! cl\d ( smoke ov] its crat] indicat$ t ! int]nal gl[ 0 n yet ext+ui%$4 ,v viol5t eruptions took place 9 ! ye>s #agid1 #ahbb1 #ahgb1 & #aijf4 ,o!r volcanoes behave q diff]5tly f ^! viol5t volcanoes1 & d h>dly any notewor?y damage4 ,among ^! is ! crat]-isl& ( ,/romboli1 situat$ betwe5 ,sicily & ,calabria4 ,?is volcano has be5 9 cont9u\s activity = ?\s&s ( ye>s4 ,its eruptions succe$ "o ano!r at int]vals rang+ f "o m9ute to tw5ty m9utes1 & its fire s]ves ! sailors z a natural light-h\se4 ,! =ce ( ?is volcano is1 ( c\rse1 unequal at diff]5t p]iods4 ,9 ! summ] ( #aijf x is said to h be5 9 unusually viol5t activity4 ,v quiet1 z a rule1 are ! eruptions ( ! great volcanoes on ,hawaii4 ,=emo/ among ! sub/ances :i* are eject$ f volcanoes is wat] vapor4 ,! cl\d float+ above ! crat] is1 = ?is reason1 ! sure/ crit]ion ( ! activity ( ! volcano4 ,viol5t eruptions drive ! masses ( /eam up into ! air to heights ( #h km4 7#e miles71 z ! illu/rations 7,figs4 #a to #d7 w %[4 ,! height ( ! cl\d may be judg$ f ! height ( ,vesuvius1 #acjj metres 7ne>ly #dcjj ft47 above sea-level4 ,! illu/ration on page #d 7,fig4 #b7 is a reproduction ( a draw+ by ,p\lett ,scrope1 repres5t+ ! ,vesuvius eruption ( ! ye> #ahbb4 ,!re seems to h be5 no w9d on ?is day2 ! masses ( /eam =m$ a cl\d ( a regul> %ape :i* rem9ds u ( a p9e-tree4 ,accord+ to ! description ( ,pl9ius1 ! cl\d notic$ at ! eruption ( ,vesuvius 9 ! ye> #gi mu/ h be5 ( ! same k9d4 ,:5 ! air is n s calm ! cl\d assumes a m irregul> %ape 7,fig4 #c74 ,cl\ds :i* rise to su* elevations z we h spok5 ( are di/+ui%$ by /rong electric *>ges4 ,! vivid fla%es ( lightn+ :i* %oot out ( ! black cl\ds add to ! t]ror ( ! awful spectacle4 ,illu/ration3 ,fig4 #b4--;,eruption ( ,vesuvius 9 #ahhb4 7,aft] a contemporane\s draw+ by ,p\lett ,scrope7 ,! ra9 :i* p\rs d[n f ?is cl\d is (t5 mix$ ) a%es & is z black z ink4 ,! a%es h a color :i* v>ies betwe5 light-gray1 yell[-gray1 br[n1 & almo/ black1 & !y consi/ ( m9ute sph]ules ( lava eject$ by ! =ce ( ! gases & rapidly congeal$ by contact ) ! air4 ,l>g] drops ( lava h>d5 to volcanic s&--! s-call$ 8lapilli0 7t is1 little /ones71 or to 8bombs10 :i* are (t5 furr[$ by ! resi/ance (f]$ by ! air1 & turn pe>-%ap$4 ,^! solid products1 z a rule1 cause ! greate/ damage due to volcanic eruptions4 ,9 ! ye> #aijf ! weight ( ^! fall+ masses 7,fig4 #d7 cru%$ 9 ! ro(s ( h\ses4 ,a lay] ( a%es #g m4 7#bc ft47 9 ?ickness buri$ ,pompeii "u a protective cru/ :i* _h cov]$ x up to days ( mod]n excavations4 ,! f9e a%es & ! muddy ra9 clung l a m\ld ( pla/] to ! dead bodies4 ,! mud h>d5$ aft]w>ds into a k9d ( cem5t1 & z ! decomposition products ( ! dead bodies 7 wa%$ away1 ! m\lds h provid$ u ) fai?ful ca/s ( ! objects t _h once be5 emb$d$ 9 !m4 ,:5 ! a%es fall into ! sea1 a lay] ( volcanic tuffa is =m$ 9 a simil> mann]1 :i* en%r9es ! animals ( ! sea & alg4 ,( ?is k9d is ! soil ( ! ,campagna ,felice1 ne> ,naples4 ,l>g] lumps ( solid /ones ) innum]able bubbles ( gases float z pumice-/one on ! sea1 & are gradually gr\nd d[n into volcanic s& by ! action ( ! waves4 ,! float+ pumice-/one has sometimes become dang]\s or1 at any rate1 an ob/acle to %ipp+1 ?r\gh its l>ge masses2 t 01 at lea/1 ! case ) ! ,krakatoa eruption ( #ahhc4 ,illu/ration3 ,fig4 #c4--;,eruption ( ,vesuvius 9 #ahgb4 7,aft] a photograph47 ,among ! gases :i* are eject$ 9 addition to wat] vapor1 c>bonic acid %\ld be m5tion$ 9 ! fir/ in/ance2 also vapors ( sulphur & sulphurett$ hydrog51 hydro*loric acid1 & *loride ( ammonium1 z well z ! *lorides ( iron & copp]1 boric acid1 & o!r sub/ances4 ,a l>ge portion ( ^! bodies is precipitat$ on ! edges ( ! volcano1 ow+ to ! sudd5 cool+ ( ! gases4 ,! m volatile con/itu5ts1 su* z c>bonic acid1 sulphurett$ hydrog51 & hydro*loric acid1 may spread ov] l>ge areas1 & de/roy all liv+ be+s by _! heat & poison4 ,x 0 ^! gases1 = example1 :i* caus$ ! awful deva/ation at ,/4 ,pi]re1 :]e #cj1jjj human lives 7 de/roy$ on ,may #h1 #aijb1 by ! eruption ( ,mont ,pele4 ,! ejection ( hydrog5 gas1 :i*1 on em]g+ f ! lava1 is burn$ to wat] by ! oxyg5 ( ! air1 has be5 obs]v$ 9 ! crat] ( ,kilauea4 ,! a%es ( ! volcanoes are sometimes c>ri$ to va/ di/ances by ! air curr5ts--e4g41 f ! we/]n coa/ ( ,s\? ,am]ica to ! ,antilles2 f ,icel& to ,norway & ,sw$52 f ,vesuvius 7#aijf7 to ,hol/e94 ,be/ kn[n 9 ?is respect is ! eruption ( ! ,krakatoa1 :i* drove ! f9e a%es up to an elevation ( #cj km4 7#ah miles74 ,! f9e/ p>ticles ( ^! a%es 7 sl[ly c>ri$ by ! w9ds to all p>ts ( ! e>?1 :]e !y caus$1 dur+ ! foll[+ two ye>s1 ! magnific5t sunrises & sunsets :i* 7 spok5 ( z 8! r$ gl[s40 ,?is gl[ 0 also obs]v$ 9 ,europe aft] ! eruption ( ,mont ,pele4 ,! du/ ( ,krakatoa fur!r suppli$ ! mat]ial = ! s-call$ 8lum9\s cl\ds ( ! night10 :i* 7 se5 9 ! ye>s #ahhc to #ahib float+ at an elevation ( ab\t #hj km4 7#ej miles71 & h5ce illum9at$ by ! light ( ! sun long aft] sunset4 ,! crat] ( ,kilauea1 on ! high volcano ( ,mauna ,loa1 9 ,hawaii--?is volcano is ab\t ( ! same height z ,mont ,blanc--has excit$ special int]e/4 ,! crat] =ms a l>ge lake ( lava hav+ an area ( ab\t #ab sq4 km4 7ne>ly #e sq4 miles71 :i*1 h[ev]1 v>ies consid]ably ) "t4 ,! lava boil+ at r$ gl[ is con/antly emitt+ masses ( gas "u slight explosions1 spurt+ out fi]y f\nta9s to a height ( #bj m4 7#fe ft47 into ! air4 ,"h & !re lava fl[s out f crevices 9 ! wall ( ! crat] d[n ! slope ( ! m\nta91 until ! surface ( ! lake ( lava has desc5d$ bel[ ^! cracks4 ,z a rule1 ?is lava is ( a ?9 fluid consi/5cy1 & x spreads1 !re=e1 r uni=mly ov] l>ge areas4 ,( a simil> k9d are also ! floods ( lava :i* are sometimes p\r$ ov] ?\s&s ( squ>e kilometres on ,icel&4 ,! s-call$ ,laki eruption ( ! ye> #aghc 0 ( a specially gr& nature4 ,?\gh occurr+ 9 an un9habit$ di/rict1 x did a great am\nt ( damage4 ,9 ! m anci5t geological p]iods1 especially 9 ! ,t]ti>y age1 simil> %eets ( lava ( va/ ext5sions h be5 spread ov] ,engl& & ,scotl& 7m ?an #ajj1jjj sq4 km41 r\ghly1 #dj1jjj sq4 miles72 ov] ,deccan1 9 ,india1 #djj1jjj sq4 kms4 7#aej1jjj sq4 miles71 up to heights ( #bjjj m4 7#fejj ft472 & ov] ,wyom+1 ,yell[/one ,p>k1 ,nevada1 ,utah1 ,oregon1 & o!r di/ricts ( ! ,unit$ ,/ates1 z well z ov] ,briti% ,columbia4 ,illu/ration3 ,fig4 #d4--,photograph ( ,vesuvius1 #aijf4 ,*iefly cl\ds ( a%es ,9 o!r cases ! sl[ly eject$ lava is *>g$ ) l>ge volumes ( gases1 :i* escape :5 ! lava congeals & bur/ x up into r\gh1 unequal blocks1 =m+ ! s-call$ block lava 7,fig4 #e74 ,! /reams ( lava c likewise produce t]rible deva/ation :5 !y desc5d into inhabit$ di/ricts2 on acc\nt ( _! sl[ motion1 !y r>ely cause loss ( life1 h[ev]4 ,:]e ! volcanic activity gradually less5s or ceases1 we c /ill trace x by ! exhalations ( gas & ! spr+s ( w>m wat] :i* we f9d 9 _m di/ricts :]e1 dur+ ! ,t]ti>y age1 p[]ful volcanoes 7 eject+ _! /reams ( lava4 ,to ?is class belong ! fam\s geys]s ( ,icel&1 ( ,yell[/one ,p>k 7,fig4 #f71 & ( ,new ,zeal&2 also ! hot spr+s ( ,bohemia1 s highly valu$ !rapeutically 7e4g41 ! ,k>lsbad ,sprudel72 ! ,fum>oli ( ,italy1 ,greece1 & o!r c\ntries1 exhal+ wat] vapor2 ! ,m(ett1 ) _! exhalations ( c>bonic acid 7( frequ5t occurr5ce 9 ! di/rict ( ! ,eifel & on bo? sides ( ! middle ,rh9e1 9 ! ,dogs ,grotto ne> ,naples1 & 9 ! ,valley ( ,dea? 9 ,java72 ! ,solfat>a1 exhal+ vapors ( sulphur--sulphurett$ hydrog5 & sulphur dioxide 7!y are f\nd ne> ,naples on ! ,phlegran ,fields & 9 ,greece72 z well z _m ( ! s-call$ mud volcanoes1 :i* eject mud1 salt wat]1 & gases 7z a rule1 c>bonic acid & hydroc>bons7--= example1 ! mud volcanoes ne> ,p>ma & ,mod5a1 9 ,italy1 & ^? ne> ,kron/adt1 9 ,transylvania4 ,illu/ration3 ,fig4 #e4--;,block lava on ,mauna ,loa ,! ext9ct volcanoes1 ( :i* "s1 l ! ,aconcagua1 #figj m4 7#bb1hgj ft471 9 ,s\? ,am]ica1 & ! ,kilimanj>o1 9 ,africa1 #fjaj m4 7#ai1gej ft471 rank among ! highe/ m\nta9s1 are expos$ to a rapid de/ruction by ! ra91 because !y consi/ l>gely ( loose mat]ials--volcanic a%es ) int]pos$ lay]s ( lava4 ,:]e ^! lava /reams exp& gradually1 !y protect ! gr\nd und]nea? f erosion by wat]1 & 9 ?is way prop] cuts are =m$ on ! edges ( ! lava /reams1 pass+ ?r\gh ! old volcano & ?r\gh ! s$im5t>y /rata at deep] levels4 ,illu/ration3 ,fig4 #f4--,! ,excelsior ,geys] 9 ,yell[/one ,p>k1 ,u4 ,s4 ,a4 ,remnant ( p[]ful volcanic activity 9 ! ,t]ti>y age ,! old volcano ( ,monte ,v5da1 ne> ,padua1 af=ds an int]e/+ example ( ?is type4 ,we c obs]ve !re h[ ! s$im5t>y lime/one has be5 *ang$ by ! lava1 :i* 0 fl[+ ov] x1 into m>ble to a dep? ( ab\t #a m4 7#c ft47 ,sometimes ! lime/one :i* is ly+ ov] ! lava has also und]gone ! same trans=mation1 :i* w\ld indicate t lava has n only be5 fl[+ above ! edge ( ! crat]1 b has also =c$ itself out on ! sides ?r\gh ! fissures betwe5 two lay]s ( lime/one4 ,massive subt]ranean lava /reams ( ?is k9d are f\nd 9 ! s-call$ lakkoli!s ( ,utah & 9 ! ,caucasus4 ,!re ! sup]ior lay]s h be5 =c$ upw>d by ! lava press+ f bel[2 ! lava froze1 h[ev]1 be=e x rea*$ ! surface ( ! e>?1 :]e x might h =m$ a volcano4 ,q a numb] ( granites1 ! s-call$ ba?oli!s1 *iefly occurr+ 9 ,norway1 ,scotl&1 & ,java1 are ( simil> orig94 ,occasionally x is only ! core ( congeal$ lava t has rema9$ ( ! :ole volcano4 ,^! cores1 :i* orig9ally fill$ ! pipe ( ! crat]1 are frequ5t 9 ,scotl& & 9 ,nor? ,am]ica1 :]e !y are designat$ 8necks0 7,fig4 #g74 ,illu/ration3 ,fig4 #g4--,mato ,tepee 9 ,wyom+1 ,u4 ,s4 ,a4 ,typical volcanic 8,neck0 ,! s-call$ caons ( ! ,colorado ,plateau1 ) _! almo/ v]tical walls1 are ! results ( ! erosive action ( riv]s4 ,a draw+ by ,dutton %[s a wall ( ?is k9d m ?an #hjj m4 7#bfjj ft47 9 height1 ?r\gh f\r fissures ( :i* lava /reams h =c$ _! way up to ! surface 7,fig4 #h74 ,ov] "o ( ^! fissures a small cone ( volcanic a%es is /ill visible1 :ile ! cones :i* probably ov]topp$ ! ?ree o!r fissures h be5 wa%$ away1 s t ! ve9s end 9 small 8necks40 ,evid5tly a v fluid lava--/rong p]c5tages ( magnesia & ( oxide ( iron r5d] ! lava m fluid ?an an admixture ( silicic acid1 & ! fluidity is fur!r increas$ by ! pres5ce ( wat]--has be5 =c$ into ! fissures :i* 7 already pres5t1 & has rea*$ ! surface ( ! e>? be=e x froze4 ,! driv+ =ce beh9d !m mu/ h be5 pretty /rong2 else ! lava /reams c\ld n h atta9$ ! necess>y velocity ( fl[4 ,illu/ration3 ,fig4 #h4--;,clefts fill$ ) lava & volcanic cone ( a%es1 ,tor[heap ,caon1 ,plateau ( ,colorado4 ,diagram4 ,:5 ! ,krakatoa 0 bl[n into ! air 9 #ahhc half ( ! volcano rema9$ beh9d4 ,?is half cle>ly %[s ! section ( ! cone ( a%es1 :i* has be5 b v slightly affect$ by ! de/ructive action ( ! wat]4 ,we f9d !re 9 ! c5tral "p ! light-color$ /opp] ( lava 9 ! volcano pipe1 & issu+ f x m light-color$ b$s ( lava1 betwe5 :i* d>k] /rata ( a%es c be se54 ,! di/ribution ( volcanoes ov] ! surface ( ! e>? is m>k$ by /rik+ regul>ities4 ,almo/ all ! volcanoes are situat$ ne> ! %ores ( ! sea4 ,a few are f\nd 9 ! int]ior ( ,ea/ ,africa2 b !y are1 at any rate1 ne> ! ,great ,lakes ( ! equatorial regions4 ,! few volcanoes :i* are suppos$ to be situat$ 9 ,c5tral ,asia mu/ be reg>d$ z d\btful4 ,we miss1 h[ev]1 volcanoes on "s sea-coa/s1 z 9 ,au/ralia & along ! long coa/-l9es ( ! ,nor!rn ,arctic ,ocean to ! nor? ( ,asia1 ,europe1 & ,am]ica4 ,volcanoes occur only :]e great cracks occur 9 ! cru/ ( ! e>? along ! sea-coa/4 ,:]e su* fissures are f\nd1 b :]e ! sea or l>ge inl& lake bas9s are n ne>--z1 = in/ance1 9 ! ,au/rian ,alps--we d n meet ) any volcanoes2 su* di/ricts are1 h[ev]1 r5[n$ = _! e>?quakes4 ,s9ce anci5t ages ! belief has be5 ent]ta9$ t ! molt5 masses ( ! int]ior ( ! e>? f9d an outlet ?r\gh ! volcanoes4 ,attempts h be5 made to e/imate ! dep? ( ! he>?s ( volcanoes1 b v diff]5t values h be5 d$uc$4 ,?us1 ! he>? "u ! volcano ( ,monte ,nuovo1 :i* 0 ?r[n up 9 ! ye> #aech on ! ,phlegran ,fields1 ne> ,naples1 has be5 cr$it$ ) dep?s v>y+ f #a4c km4 to #fj km4 7#a mile to #dj miles72 = ! ,krakatoa1 e/imates ( m ?an #ej km4 7#cj miles7 h be5 made4 ,all ^! calculations are r aimless2 = ! volcanoes are probably situat$ on folds ( ! e>?-cru/1 ?r\gh :i* ! fluid mass 7! magma7 ru%es =? 9 w$ges f ! int]ior ( ! e>?1 & x w presumably be v difficult to say :]e ! he>? ( magma ends & :]e ! volcanic pipe comm5ces4 ,! ,kilauea gives ! visitor ! impression t he is /&+ ov] an op5+ 9 ! cru/ ( ! e>?1 ?r\gh :i* ! molt5 mass ru%es =? directly f ! int]ior ( ! e>?4 7,fig4 #i47 ,illu/ration3 ,fig4 #i4--,! ,kilauea ,crat] on ,hawaii ,z reg>ds ! e>?-cru/1 we "k f obs]vations 9 bore-holes made 9 diff]5t p>ts ( ! _w t ! temp]ature increases r rapidly ) ! dep?1 on an av]age by ab\t ?irty degrees ,c5t4 p] kilometre 7ab\t #a4f ,f4 p] #ajj feet74 ,x mu/ be rem>k$1 h[ev]1 t ! dep? ( our deepe/ bore-holes h>dly exce$s #b km4 7,p>u*[itz1 9 ,silesia1 #bjjc m41 or #fegj ft42 ,s*ladeba*1 ne> ,m]seburg1 ,prussian ,saxony1 #agbj m474 ,if ! temp]ature %\ld g on increas+ at ! rate ( #cj degrees ,c5t4 = ea* fur!r kilometre1 ! temp]ature at a dep? ( #dj kilometres %\ld atta9 degrees at :i* all ! common rocks w\ld melt4 ,b ! melt+-po9t c]ta9ly rises at ! same "t z ! pressure4 ,! importance ( ?is circum/ance 01 h[ev]1 mu* exagg]at$ :5 x 0 believ$ t = ?is reason ! int]ior ( ! e>? might possibly be solid4 ,tammann has %[n by direct exp]im5ts t ! temp]ature ( fusion only rises up to a c]ta9 pressure1 & t x beg9s to decrease aga9 on a fur!r increase ( pressure4 ,! dep?s indicat$ above are !re=e n q correct4 ,if we assume1 h[ev]1 t o!r k9ds ( rock behave l diabase--! melt+-po9t ( :i*1 accord+ to ! det]m9ations ( ,b>us1 rises by #a ,c5t4 = ea* #dj atmosph]es ( pressure correspond+ to a dep? ( #aee m4--we %\ld conclude t ! solid cru/ ( ! e>? c\ld n h a great] ?ickness ?an #ej or #fj km4 7#dj miles74 ,at great] dep?s we %\ld !re=e p5etrate into ! fus$ mass4 ,on acc\nt ( its small] d5sity ! silicic acid w be conc5trat$ 9 ! upp] /rata ( ! molt5 mass1 :ile ! basic portions ( ! magma1 :i* are ri*] 9 iron oxide1 w collect 9 ! l[] /rata1 ow+ to _! great] d5sity4 ,?is magma we h to picture to ourselves z an extremely viscid liquid resembl+ asphalt4 ,! exp]im5ts ( ,day & ,all5 %[ t rods1 support$ at _! ends1 ( #cj #b #a mm4 ( diff]5t m9]als1 l ! feldsp>s microcl9e & albite1 c\ld reta9 _! %ape = ?ree h\rs )\t curv+ noticeably1 al?\gh _! temp]ature 0 ab\t a hundr$ degrees above _! melt+-po9t1 & al?\gh !y appe>$ completely fus$1 or1 m correctly1 completely vitrifi$ :5 tak5 out ( ! furnace4 ,^! molt5 silicates behave v diff]5tly f o!r liquids l wat] & m]cury1 ) :i* we are m accu/om$ to deal4 ,! motion & diffusion 9 ! magma1 & especially 9 ! v visc\s & sluggi% acid portions ( ! upp] /rata1 w !re=e be exce$+ly small1 & ! magma w behave almo/ l a solid body1 l ! m9]als ( ! exp]im5ts ( ,day & ,all54 ,! magmas ( volcanoes l ,etna1 ,vesuvius1 & ,pantell>ia may1 !re=e1 h q diff]5t compositions1 z we %\ld conclude f _! lavas )\t our be+ =c$ to believe1 ) ,/bel1 t ^! ?ree he>?s ( volcanoes are completely sep>at$1 ?\gh n f> remov$ f "o ano!r4 ,9 ! lava ( ,vesuvius a temp]ature ( #ajjj or #aajj degrees has be5 f\nd at ! l[] extremity ( ! /ream4 ,f ! occurr5ce 9 ! lava ( c]ta9 cry/als l leucite & oliv91 :i* we h reason to assume mu/ h be5 =m$ be=e ! lava left ! crat]1 x has be5 conclud$ t ! lava temp]ature _c h be5 high] ?an #adjj degrees be=e x left ! volcanic pipe4 ,x w\ld1 h[ev]1 be errone\s to d$uce f ! temp]ature ( ! lava ( ,vesuvius t ! he>? ( ! volcano mu/ be situat$ at a dep? ( approximately #ej kilometres4 ,mo/ likely its dep? is mu* small]1 p]haps n ev5 #aj kilometres4 ,= !re1 z ev]y:]e :]e volcanoes occur1 ! cru/ ( ! e>? is /rongly furr[$1 & ! magma w j at ! spots :]e we f9d volcanoes come mu* ne>] to ! surface ( ! e>? ?an else:]e4 ,! importance ( wat] = ! =mation ( volcanoes probably lies 9 ! fact t1 9 ! neighborhood ( cracks "u ! bottom ( ! sea1 ! wat] p5etrates d[n to consid]able dep?s4 ,:5 ! wat] rea*es a /ratum ( a temp]ature ( #cfe degrees--! s-call$ critical temp]ature ( wat]--x c no long] rema9 9 ! liquid /ate4 ,t w\ld n prev5t1 h[ev]1 its p5etrat+ /ill f>!r into ! dep?s1 9 spite ( its gase\s condition4 ,z soon z ! vapor comes 9 contact ) magma1 x w eag]ly be absorb$ by ! magma4 ,! reason is t wat] ( a temp]ature ( m ?an #cjj degrees is a /rong] acid ?an silicic acid2 ! latt] is !re=e expell$ by x f its comp\nds1 ! silicates1 :i* =m ! ma9 con/itu5ts ( ! magma4 ,! high] ! temp]ature1 ! great] ! p[] ( ! magma to absorb wat]4 ,ow+ to ?is absorption ! magma swells & becomes at ! same "t m fluid4 ,! magma is !re=e press$ out by ! action ( a pressure :i* is analog\s to ! osmotic pressure by virtue ( :i* wat] p5etrates ?r\gh a membrane into a solution ( sug> or salt4 ,?is pressure may become equival5t to ?\s&s ( atmosph]es1 & ?is v pressure w\ld raise ! magma up ! volcanic pipe ev5 to a height ( #fjjj m4 7#bj1jjj feet7 above ! sea-level4 ,z ! magma is asc5d+ 9 ! volcanic pipe x is sl[ly cool$1 & its capacity = b9d+ wat] dim9i%es ) fall+ temp]ature4 ,! wat] w h5ce escape "u viol5t ebullition1 te>+ drops & l>g] lumps ( lava ) x1 :i* fall d[n aga9 z a%es or pumice-/one4 ,aft] ! lava has fl[n out ( ! crat] & is sl[ly cool+1 x cont9ues to give (f wat]1 break+ up "u ! =mation ( block lava 7see ,fig4 #e74 ,if1 on ! o!r h&1 ! lava 9 ! crat] ( ! volcano is comp>atively at re/1 z 9 ,kilauea1 ! wat] w escape m sl[ly2 ow+ to ! long-cont9u$ contact ( ! surface lay] ( lava ) ! air1 little wat] w rema9 9 x1 ! wat] be+1 s to say1 remov$ by a]ation1 & ! lava /reams w !re=e1 :5 congeal+1 =m m smoo? surfaces4 ,9 "s cases volcanoes h be5 prov$ 7,/bel & ,branco7 n to be 9 connection ) any fractures 9 ! cru/ ( ! e>?4 ,t holds1 = in/ance1 = sev]al volcanoes ( ! e>ly ,t]ti>y age 9 ,swabia4 ,we may imag9e t ! pressure produc$ by ! swell+ ( ! magma became s p[]ful z to be able to break ?r\gh ! e>?-cru/ at ?9n] spots1 ev5 9 ! abs5ce ( previ\s fissures4 ,if1 9 our consid]ation1 we foll[ ! magma f>!r into ! dep?s1 we %all n f9d any reason = assum+ t ! temp]ature w n rise f>!r t[>ds ! int]ior ( ! e>?4 ,at dep?s ( #cjj or #djj km4 7#bej miles7 ! temp]ature mu/ f9ally atta9 degrees su* t no sub/ance w be able to exi/ 9 any o!r /ate ?an ! gase\s4 ,)9 ?is lay] ! int]ior ( ! e>? mu/1 !re=e1 be gase\s4 ,f our k ( ! behavior ( gases at high temp]atures & pressures1 we may safely conclude t ! gases 9 ! c5tral portions ( ! e>? w behave almo/ l an extremely viscid magma4 ,9 c]ta9 respects !y may probably be comp>$ to solid bodies2 _! compressibility1 9 p>ticul>1 w be v small4 ,we might ?9k t we c\ld n possibly le>n any?+ conc]n+ ! condition ( ^? /rata4 ,e>?quakes h1 h[ev]1 suppli$ u ) a little in=mation4 ,su* gase\s masses mu/ fill by f> ! greate/ "p ( ! e>?1 & !y mu/ h a v high specific gravity2 = ! av]age d5sity ( ! e>? is #e4eb1 & ! out] /rata1 ! ocean & ! masses ( ! surface :i* are kn[n to u1 h small] d5sities4 ,! ord9>y rocks possess a d5sity rang+ f #b4e to #c4 ,x mu/1 !re=e1 be assum$ t ! mat]ials ( ! inn]mo/ portions ( ! e>? mu/ be metallic1 & ,wie*]t1 9 p>ticul>1 has advocat$ ?is view4 ,iron w presumably =m ! *ief con/itu5t ( ?is gas ( ! c5tral e>?4 ,spectrum analysis tea*es u t iron is a v important con/itu5t ( ! sun4 ,we "k1 fur!r1 t ! metallic portions ( ! meteorites consi/ ess5tially ( iron2 & f9ally t]re/rial magnetism indicates t !re mu/ be l>ge masses ( iron 9 ! int]ior ( ! e>?4 ,we h also reason to believe t ! native iron occurr+ 9 nature--e4g41 ! well-kn[n iron ( ,ovifak1 9 ,gre5l&--is ( volcanic orig94 ,! mat]ials 9 ! gase\s int]ior ( ! e>? w1 ow+ to _! high d5sity1 behave 9 *emical & physical respects l liquids4 ,z sub/ances l iron w1 also at v high temp]atures1 h a f> high] specific gravity ?an _! oxides1 & ^! aga9 h a high] gravity ?an _! silicates1 we h to assume t ! gases 9 ! core ( ! e>? w almo/ exclusively be metallic1 t ! out] portions ( ! core w conta9 ess5tially oxides1 & ^? f>!r out aga9 mo/ly silicates4 ,! fus$ magma w1 on p5etrat+ 9 ! %ape ( ba?oli!s into ! upp] lay]s1 probably be divid$ into two portions1 ( :i* "o1 ! light] & gase\s1 w conta9 wat] & sub/ances soluble 9 x2 :ile ! o!r1 heavi] portion1 w ess5tially consi/ ( silicates ) a l[] p]c5tage ( wat]4 ,! m fluid portion1 ri*] 9 wat]1 w be secret$ 9 ! high] lay]s1 w p5etrate into ! surr\nd+ s$im5t>y /rata1 especially into _! fissures1 & w fill !m ) l>ge cry/als1 (t5 ( metallurgical value--e4g41 ( ! ores ( t91 copp]1 & o!r metals1 :ile ! wat] w sl[ly evaporate ?r\gh ! sup]pos$ /rata4 ,! m viscid & sluggi% mass ( silicates1 on ! o!r h&1 w congeal1 ?anks to its great viscosity1 to glass1 or1 :5 ! cool+ is v sl[1 to small cry/als4 ,we n[ turn to e>?quakes4 ,no c\ntry has be5 absolutely sp>$ by e>?quakes4 ,9 ! di/ricts b\nd+ ^u ! ,baltic1 & especially 9 nor!rn ,russia1 !y h1 h[ev]1 be5 ( a q h>mless type4 ,! reason is t ! e>?-cru/ !re has be5 ly+ undi/urb$ = long geological epo*s & has nev] be5 fractur$4 ,! comp>atively sev]e e>?quake :i* %ook ! we/ coa/ ( ,sw$5 on ,octob] #bc1 #aijd1 to an unusually heavy degree1 )\t1 h[ev]1 caus+ any notewor?y damage 7a few *imneys 7 knock$ ov]71 0 caus$ by a fault ( relatively pron\nc$ "* = ^? di/ricts 9 ! ,skag]-,rack--a cont9uation ( ! deepe/ fold 9 ! bottom ( ! ,nor? ,sea1 ! s-call$ ,norwegian ,tr\gh1 :i* runs p>allel to ! ,norwegian coa/4 ,9 ,g]many1 ! ,vogtl& & ! di/ricts on bo? sides ( ! middle ,rh9e h frequ5tly be5 visit$ by e>?quakes4 ,( o!r ,european c\ntries1 ,switz]l&1 ,spa91 ,italy1 & ! ,balkan ,p59sula1 z well z ! ,k>/ di/ricts ( ,au/ria1 h (t5 suff]$ f e>?quakes4 ,illu/ration3 ,fig4 #aj4--;,*ief e>?quake c5tres1 accord+ to ! ,briti% ,association ,committee ,accord+ to ! committee appo9t$ by ! ,briti% ,association = ! inve/igation ( e>?quakes--a committee :i* has contribut$ a great deal to our k ( ^! great natural ph5om5a--e>?quakes ( "s importance emanate f c]ta9 c5tres :i* h be5 indicat$ on ! subjo9$ map 7,fig4 #aj74 ,! mo/ important among ^! regions comprises ,f>!r ,india1 ! ,sunda ,isles1 ,new ,gu9ea1 & ,nor!rn ,au/ralia2 x is m>k$ on ! map by ! lett] ,f4 ,f ?is di/rict h emanat$ 9 ! six-ye> p]iod #ahii-aijd no few] ?an #bdi e>?quakes1 :i* h be5 record$ 9 _m obs]vatories f> remov$ f "o ano!r4 ,?is e>?quake c5tre ,f is closely relat$ to ! "o m>k$ ,e1 9 ,japan1 f :i* #ahi e>?quakes h proce$$4 ,next to ?is comes ! ext5sive di/rict ,k ) #agd e>?quakes1 compris+ ! mo/ important folds 9 ! cru/ ( ! ,old ,_w1 includ+ ! m\nta9 *a9s f ! ,alps to ! ,himalaya4 ,?is di/rict is int]e/+1 because x has be5 di/urb$ by a great _m e>?quakes1 al?\gh x is almo/ entirely situat$ on ! ,cont95t4 ,aft] t we h ! di/ricts ,a1 ,b1 ,c1 ) #abe1 #ih1 & #ie e>?quakes4 ,!y are situat$ ne> l9es ( fracture 9 ! e>?-cru/ along ! ,am]ican coa/ ( ! ,pacific ,ocean & ! ,c>ibbean ,sea4 ,di/rict ,d1 ) #gh e>?quakes1 is simil>ly situat$4 ,! ?ree la/-m5tion$ di/ricts1 ,b1 ,c1 ,d1 z well z ,g1 betwe5 ,madagasc> & ,india1 ) #he e>?quakes1 all seem to be surpass$ by ! di/rict ,h 9 ! ea/]n ,atlantic1 ) its #ajg e>?quakes4 ,^! latt] are1 h[ev]1 relatively feeble1 & we owe _! accurate records probably to ! circum/ances t a great _m e>?quake obs]vatories are situat$ )9 ! imm$iate surr\nd+s ( ?is di/rict4 ,! same may be said ( ! di/rict ,i1 or ,newf\ndl&1 :i* is n *>act]iz$ by _m e>?quakes1 & ( ! di/rict ,j1 betwe5 ,icel& & ,spitzb]g51 ) #ca & #ai e>?quakes respectively4 ,! la/ on ! li/ us$ to be ! di/rict ,l1 situat$ ab\t ! ,s\? ,pole1 ) only eight e>?quakes4 ,?is small numb] is probably m]ely due to ! want ( obs]vatories 9 ^? p>ts ( ! e>?4 ,ano!r di/rict1 ,m1 has f9ally be5 add$1 :i* ext5ds to ! s\?we/ f ,new ,zeal&4 ,no few] ?an #ge int5se e>?quakes 7 record$ betwe5 ,m>* #ad & ,novemb] #bc1 #aijc1 by ! ,discov]y ,exp$ition1 9 #gj s\!rn latitude & #agh ea/]n longitude4 ,e>?quakes commonly occur 9 sw>ms or gr\ps4 ,?us1 m ?an #bjjj %ocks 7 c\nt$ on ,hawaii 9 ,m>*1 #ahfh4 ,dur+ ! e>?quakes :i* deva/at$ ! di/rict ( ,phokis1 9 ,greece1 9 #ahgj-gc1 %ocks succe$$ "o ano!r = a long "t at int]vals ( ?ree seconds4 ,dur+ ! :ole p]iod ( ?ree & a half ye>s ab\t half a million %ocks 7 c\nt$1 &1 fur!r1 a qu>t] ( a million subt]ranean reports :i* 7 n accompani$ by noticeable concussions4 ,yet ( all ^! %ocks only ab\t #cjj did notewor?y damage1 & only #ce 7 consid]$ wor? be+ report$ 9 ! newspap]s4 ,! concussion ( ,octob] #bc1 #aijd1 belong$ to a gr\p :i* la/$ f ,octob] #aj to ,octob] #bh1 & 9 :i* num]\s small tremors 7 notic$1 especially on ,octob] #bd & #be4 ,! e>?quake ( ,san ,francisco comm5c$ on ,april #ah1 #aijf1 at #e hrs4 #ab m94 #f sec4 ,a4,m4 7,pacific ,ocean "t71 & end$ at #e hrs4 #ac m94 #aa sec1 la/+ !re=e #a m9ute & #e seconds4 ,twelve small] %ocks succe$$ 9 ! foll[+ h\r4 ,be=e #f hrs4 #eb m94 ,p4,m41 n9ete5 fur!r concussions 7 c\nt$1 & v>i\s small] %ocks succe$$ 9 ! foll[+ days4 ,) su* gr\ps ( e>?quakes weak] tremors usually prec$e ! viol5t de/ructive %ocks & give a w>n+4 ,un=tunately ?is is n always s1 & no w>n+ 0 giv5 by ! e>?quakes :i* de/roy$ ,lisbon 9 #agee & ,c>acas 9 #ahab1 nor by ^? :i* deva/at$ ,agram 9 #ahhj1 nor1 f9ally1 9 ! case ( ! ,san ,francisco disa/]4 ,a n v sev]e e>?quake )\t feebl] precursors befell ,is*ia 9 #ahha1 :ile ! viol5t cata/rophe :i* deva/at$ ?is magnific5t isl& 9 #ahhc 0 h]ald$ by sev]al w>n+s4 ,z 9 ,san ,francisco & ,*ili 9 #aijf1 less viol5t concussions g5]ally succe$ ! de/ructive %ocks4 ,e>?quakes l t ( ,lisbon 9 #agee1 consi/+ ( a s+le %ock1 are v r>e4 ,! viol5t concussions (t5 produce l>ge fissures 9 ! gr\nd4 ,su* 7 notic$ 9 sev]al places at ,san ,francisco4 ,"o ( ! l>ge/ fissures kn[n1 t ( ,midori1 9 ,japan1 0 caus$ by ! e>?quake ( ,octob] #bj1 #ahia4 ,x left a displacem5t ( ! gr\nd rang+ up to #f m4 7#bj ft47 9 ! v]tical & #d m4 7#ac ft47 9 ! horizontal direction4 ,?is crack _h a l5g? ( n less ?an #fe km4 7#dj miles74 ,ext5sive fissures 7 also =m$ by ! e>?quakes ( ,calabria1 9 #aghc1 at ,monte ,san ,angelo1 & 9 ! s&/ones ( ! ,blpakrm ,plateau 9 ,india1 9 #ahig4 ,9 m\nta9\s di/ricts falls ( rock are a frequ5t consequ5ce ( ! =mation ( fissures & e>?quakes4 ,a l>ge numb] ( rocks fell 9 ! neighborhood ( ,delphi dur+ ! ,phokian e>?quake4 ,on ,janu>y #be1 #acdh1 an e>?quake s5t d[n a l>ge portion ( ,m\nt ,dobrats* 79 ! ,alps ( ,villa*1 9 ,c>9?ia1 :i* is n[ mu* frequ5t$ by t\ri/s7 & buri$ two t[ns & sev5te5 villages4 ,! e>?quake ( ,april #ah1 #aijf1 9 ,cali=nia />t$ f a crack :i* ext5ds f ! m\? ( ,ald] ,creek1 ne> ,po9t ,ar5a1 runn+ p>allel ) ! coa/-l9e mo/ly inl&1 !n ent]+ ! sea ne> ,san ,francisco1 & turn+ aga9 inl& betwe5 ,santa ,cruz & ,san ,jos1 f9ally proce$+ via ,*itt5d5 up to ,m\nt ,p9os1 a di/ance ( ab\t #fjj km4 7#djj miles71 9 ! direction ( ,n4 #ce ,w4 to ,s4 #ce ,e4 ,along ?is crack ! two masses ( ! e>? h be5 displac$ s t ! gr\nd situat$ to ! s\?we/ ( ! fissure has be5 mov$ by ab\t #c m4 7#aj ft471 & 9 "s spots ev5 by #f m4 7#bj ft47 t[>ds ! nor?we/4 ,9 "s localities 9 ,sonoma & ,m5doc9o c\nties ! s\?we/]n "p has be5 rais$1 b n[h]e by m ?an #a4b m4 7#d ft474 ,?is is ! longe/ crack :i* has ev] be5 notic$ 9 connection ) an e>?quake4 ,illu/ration3 ,fig4 #aa4--;,clefts 9 ,val5tia ,/reet1 ,san ,francisco1 aft] ! e>?quake ( #aijf ,! e>?quake ov]1 ! gr\nd does n always return to its orig9al position1 b rema9s 9 a m or less wavy condition4 ,?is c mo/ easily be obs]v$ 9 di/ricts :]e /reets or railways cross ! gr\nd4 ,x is report$1 = in/ance1 t ! track ( ! tramway-l9es 9 ,m>ket ,/reet1 ! *ief ?or\ghf>e ( ,san ,francisco1 =m$ l>ge wavelike curves aft] ! e>?quake4 ,z a consequ5ce ( ! displacem5ts 9 ! int]ior ( ! e>? & ( ! =mation ( fissures1 riv] c\rses are *ang$1 spr+s become exhau/$1 & new spr+s arise4 ,t 0 ! case1 = in/ance1 9 ,cali=nia 9 #aijf4 ,! gr\nd wat] (t5 ru%es out ) consid]able viol5ce1 te>+ ) x s& & mud & /ones1 & pil+ !m up1 occasionally =m+ little crat]s 7,fig4 #ab74 ,ext5sive floods may also be caus$ on su* occasions4 ,by su* a flood ! anci5t ,olympia 0 subm]g$ "u a lay] ( riv] s& :i* = "s "t pres]v$ f de/ruction ! anci5t ,greek ma/]pieces ( art--among !m ! fam\s /atue ( ,h]mes4 ,! floods aft]w>ds rec$$1 & ! treasures ( anci5t ,olympia c\ld be excavat$4 ,l ! natural wat] *annels & art]ies 9 ! int]ior ( ! e>?1 wat] ma9s are displac$ by ! concussions4 ,! direct damage caus$ by ! floods is (t5 less important ?an ! damage due to ! impossibility ( ext+ui%+ ! fires :i* foll[ ! de/ruction ( ! build+s4 ,x 0 ! fires t did mo/ ( ! enorm\s mat]ial damage 9 ! de/ruction ( ,san ,francisco4 ,/ill great] deva/ation is wr\ght by ! ocean waves ?r[n up by e>?quakes4 ,we h already ref]r$ to ! flood ( ,lisbon 9 #agee1 :i* 0 felt on ! we/]n coa/ ( ,norway & ,sw$54 ,ano!r wave1 9 #aeaj1 dev\r$ #aji mosques & #ajgj h\ses 9 ,con/ant9ople4 ,ano!r wave1 aga91 invad$ ,kama%i1 9 ,japan1 on ,june #ae1 #ahif1 swept away #gfjj h\ses & kill$ #bg1jjj p4 ,we h repeat$ly allud$ to ! disa/r\s flood-wave ( ,krakatoa ( #ahhc4 ,?is wave trav]s$ ! :ole ( ! ,indian ,ocean1 pass+ to ! ,cape ( ,good ,hope & ,cape ,horn1 & travell$ r\nd half ! globe aft]w>ds4 ,ev5 m rem>kable 0 ! a]ial wave1 :i* spread l an explosion wave4 ,illu/ration3 ,fig4 #ab4--,s& crat]s & fissures1 produc$ by ! ,cor9? e>?quake ( #ahfa4 ,9 ! wat]1 bran*es ( flood$ trees ,:ile ! mo/ viol5t cannonades are r>ely he>d = m ?an #aej km4 7#ie miles7--9 a s+le case at a di/ance ( #bgj km4 7#agj miles7--! eruption ( ,krakatoa 0 he>d at ,alice ,spr+s1 at a di/ance ( #cfjj kilometres1 & on ! isl& ( ,rodriguez1 at almo/ #dhjj km4 7#cjjj miles74 ,! b>ographs ( ! meteorological /ations fir/ m>k$ a sudd5 rise & !n a decid$ s9k+ ( ! air pressure1 succe$$ by a few small] fluctuations4 ,^! air pulses 7 repeat$ 9 "s places z _m z sev5 times4 ,we may !re=e assume t ! a]ial wave pass$ ^! places ?ree times 9 ! "o direction1 & ?ree times 9 ! o!r1 travell+ r\nd ! e>?4 ,! velocity ( propagation ( ?is wave 0 #cad4b m4 7#ajcj ft47 p] second1 correspond+ to a temp]ature ( -#bg ,c5t4 7#ag ,f47 :i* prevails at an altitude ( ab\t #h km4 7#e miles7 above ! e>?'s surface1 at :i* altitude ?is wave may h travell$4 ,)9 ! la/ decade a peculi> ph5om5on 7lead+ to :at is designat$ v>iation ( latitudes7 has be5 /udi$4 ,! poles ( ! axis ( ! e>? appe> to move 9 a v irregul> curve ab\t _! mean axis4 ,! movem5t is exce$+ly small4 ,! deviation ( ! ,nor? ,pole f its mean position does n am\nt to m ?an #aj m4 7ab\t #cc ft474 ,x has be5 believ$ t ^! motions ( ! ,nor? ,pole are subject to sudd5 fluctuations aft] unusually viol5t e>?quakes1 especially :5 su* concussions foll[ at rapid int]vals4 ,t w\ld give u1 p]haps m ?an any o!r obs]vation1 an idea ( ! =ce ( e>?quakes1 s9ce !y w\ld appe> to be able to di/urb ! equilibrium ( ! :ole mass ( our globe4 ,a sev]ely felt effect ( e>?quakes1 ?\gh mo/ p p]haps pay little att5tion to x1 is ! de/ruction ( subm>9e cables4 ,! gutta-p]*a %ea?s ( cables are frequ5tly f\nd 9 a fus$ condition1 sugge/+ volcanic eruptions "u ! bottom ( ! sea4 ,we take c>e n[ to avoid e>?quake c5tres 9 lay+ telegraphic cables4 ,_! positions h be5 asc]ta9$ by ! mo/ mod]n inve/igations 7see ,fig4 #aj74 ,p h always be5 incl9$ to look = a connection betwe5 e>?quakes & volcanic eruptions4 ,! connection is unque/ionable 9 a l>ge numb] ( viol5t e>?quakes4 ,9 ord] to e/abli% x1 ! above-m5tion$ committee ( ! ,briti% ,association has compil$ ! foll[+ table ( ! hi/ory ( ! e>?quakes ( ! ,antilles3 #afib4--,port ,royal1 ,jamaica1 de/roy$ by an e>?quake2 l& s9k+ into ! sea4 ,eruption on ,/4 ,kitts4 #agah4--,t]rible e>?quake on ,/4 ,v9c5t1 foll[$ by an eruption4 #agff-fg4--;,great %ocks 9 nor!a/]n ,s\? ,am]ica1 9 ,cuba1 ,jamaica1 & ! ,antilles4 ,eruption on ,santa ,lucia4 #agig4--;,e>?quake 9 ,quito1 loss ( #dj1jjj lives4 ,concussions 9 ! ,antilles1 eruption on ,guadel\pe4 #ahjb4--,viol5t %ocks 9 ,antigua4 ,eruption on ,guadel\pe4 #ahab4--;,c>acas1 capital ( ,v5ezuela1 totally de/roy$ by e>?quake4 ,viol5t %ocks 9 ! ,s\!rn ,/ates ( ,nor? ,am]ica1 comm5c+ on ,novemb] #aa1 #ahaa4 ,eruptions on ,/4 ,v9c5t & ,guadel\pe4 #ahce-cf4--,viol5t concussions 9 ,*ili & ,c5tral ,am]ica4 ,eruption on ,guadel\pe4 #aijb4--;,april #ai4 ,viol5t %ocks1 de/roy+ _m t[ns ( ,c5tral ,am]ica4 ,mont ,pele1 on ,m>t9ique1 9 activity4 ,eruption on ,may #c4 ,subm>9e cables break1 sea rec$es4 ,r5ew$ viol5t movem5ts ( ! sea on ,may #h1 #ai1 #bj4 ,eruption on ,/4 ,v9c5t1 cable de/roy$ on ,may #g4 ,viol5t eruption ( ,mont ,pele on ,may #h4 ,de/ruction ( ,/4 ,pi]re4 ,num]\s small] e>?quakes4 ,?is table di/9ctly m>ks ! re/less /ate ( affairs 9 t "p ( ! e>?1 & h[ quiet & safe matt]s are comp>atively 9 old ,europe1 especially 9 ! nor?4 ,"s p>ts ( ,c5tral ,am]ica are s p]si/5tly visit$ by e>?quakes t "o ( !m1 ,salvador1 has be5 *ri/5$ 8,s*aukelmatte40 ,x is n say+ too mu* to ass]t t ! e>? is !re incessantly trembl+4 ,o!r di/ricts :i* are v frequ5tly visit$ are ! ,kuriles & ,japan1 z well z ! ,ea/ ,indian isl&s4 ,9 all ^! c\ntries ! cru/ ( ! e>? has be5 brok5 & fold$ )9 comp>atively rec5t epo*s 7*iefly 9 ! ,t]ti>y age7 by num]\s fissures1 & _! compression is /ill go+ on4 ,illu/ration3 ,fig4 #ac4--;,e>?quake l9es 9 l[] ,au/ria ,! small] e>?quakes1 ( :i* n less ?an #cj1jjj are c\nt$ 9 ! c\rse ( a ye>1 d n /& 9 any clos] relation to volcanic eruptions4 ,?is is also ! case = a numb] ( l>ge e>?quakes1 among :i* we h to c\nt ! ,san ,francisco e>?quake4 ,x is assur$ ) good reason t e>?quakes are (t5 produc$ at ! bottom ( ! sea1 :]e !re is a /rong slope1 by slips ( s$im5t>y /rata :i* h be5 wa%$ d[n f ! l& into ! sea 9 ! c\rse ( c5turies4 ,milne believes t ! seaquake ( ,kama%i ( ,june #ae1 #ahif1 0 ( ?is "*4 ,concussions may ev5 be promot$ by ! diff]5t load+ ( ! e>? result+ f ! fluctuations 9 ! pressure ( ! air above x4 ,small]1 ?\gh occasionally r viol5t1 e>?quakes are n infrequ5t 9 ! neighborhood ( ,vi5na4 ,on ! map 7,fig4 #ac7 we see ?ree l9es4 ,! l9e ,a ,b is call$ ! !rmal l9e1 because along x a numb] ( hot spr+s1 ! !rm ( ,meidl+1 ,bad51 ,vslau1 etc41 are locat$1 :i* are highly valu$2 ! o!r l9e ,b ,c is call$ ! ,kamp l9e1 because x is trav]s$ by ! riv] ,kamp2 & ! ?ird ,b ,f is call$ ! ,mrz l9e1 aft] ! riv] ,mrz4 ,! ma9 railway-track betwe5 ,vi5na & ,bruck foll[s ! valleys ( ,a ,b & ,e ,f4 ,^! l9es1 :i* probably correspond to l>ge fissures 9 ! e>?-cru/1 are kn[n z s\rces ( num]\s e>?quakes4 ,! di/rict ab\t ,wi5] ,neu/adt1 :]e ! ?ree l9es int]sect1 is (t5 %ak5 by viol5t e>?quakes2 "s ( _! dates h be5 m>k$ on ! map4 ,! curve :i* is indicat$ by ! lett]s ,x ,x on ! map m>ks ! outl9es ( an e>?quake :i* />t$ on ,janu>y #c1 #ahgc1 f bo? sides ( ! ,kamp l9e4 ,x is /rik+ to see h[ ! e>?quake spread 9 ! loose gr\nd ( ! pla9 betwe5 ,/4 ,plt5 & ,tulln1 :ile ! masses ( rock situat$ to ! nor?we/ & s\!a/ =m$ ob/acles to ! propagation ( ! e>?quake waves4 ,illu/ration3 ,fig4 #ad4--,libr>y build+ ( ,lel& ,/an=d ,junior ,univ]sity1 9 ,cali=nia1 aft] ! e>?quake ( #aijf4 ,! photograph %[s ! great /r5g? ( iron /ructures 9 comp>ison to ! /r5g? ( brickwork4 ,! effect ( ! e>?quake on wood5 /ructures c be se5 9 ,fig4 #aa ,simil> conclusions h be5 d$uc$ f ! /udy ( ! spread+ ( ! waves :i* de/roy$ ,*>le/on1 ,s\? ,c>ol9a1 9 #ahhf4 ,tw5ty-sev5 lives 7 de/roy$ by ?is %ock4 ,x 0 ! mo/ t]rible e>?quake t ev] visit$ ! ,unit$ ,/ates be=e ! ye> #aijf4 ,9 ! ,*>le/on concussion ! ,alleghany ,m\nta9s prov$ a p[]ful b> aga9/ ! fur!r propagation ( ! %ocks1 :i* all ! m easily travell$ 9 ! loose soil ( ! ,mississippi ,valley4 ,9 ,san ,francisco1 likewise1 ! wor/ deva/ation fell ^u ^? p>ts ( ! t[n :i* _h be5 built ^u ! loose1 p>tly made gr\nd 9 ! neighborhood ( ! h>bor1 :ile ! build+s erect$ on ! fam\s m\nta9 ridges ( ,san ,francisco suff]$ comp>atively little damage1 9 s f> z !y 7 n rea*$ by ! de/ructive fires4 ,z reg>ds ! de/ructive effects ( ! e>?quake 9 ,san ,francisco1 ! build+-gr\nd ( t city has be5 divid$ into f\r classes 7! fir/ is ! safe/1 ! la/ ! mo/ unsafe7--namely3 #a4 ,rocky soil4 #b4 ,valleys situat$ betwe5 rocks & fill$ up by nature 9 ! c\rse ( "t4 #c4 ,s&-dunes4 #d4 ,soil creat$ by artificial fill+ up4 ,?is latt] soil 8behav$ l a semiliquid jelly 9 a di%10 accord+ to ! report ( ! ,e>?quake ,commission4 ,= simil> reasons ! sky-scrap]s1 con/ruct$ ( /eel on deep f\ndations1 /ood firme/4 ,aft] !m came brick h\ses1 ) well-jo9$ & cem5t$ walls on deep f\ndations4 ,! weakness ( wood5 h\ses prov$ ma9ly due to ! poor connection ( ! beams1 a defect :i* might easily be rem$i$4 ,! sup]iority ( ! /eel /ructure w be app>5t f ! illu/rations 7,figs4 #aa & #ad74 ,! spots situat$ j ov] ! crack1 ( :i* we spoke on page #be1 suff]$ ! mo/ s]i\s damage4 ,next to !m1 deva/ation befell especially localities :i*1 l ,santa ,rosa1 ,san ,jos1 & ,palo ,alto ) ,lel& ,/an=d ,junior ,univ]sity1 are situat$ on ! loose soil ( ! valley1 ^: deepe/ portions are cov]$ by ! bay ( ,san ,francisco4 ,! spl5didly end[$ ,cali=nia ,univ]sity1 9 ,b]keley1 & ! fam\s ,lick ,obs]vatory1 bo? erect$ on rocky gr\nd1 =tunately escap$ )\t any notable damage4 ,! map sket* 7,fig4 #ae7 by ,suess repres5ts ! e>?quake l9es ( ,sicily & ,calabria4 ,^! di/ricts h1 z m5tion$ be=e1 be5 deva/at$ by sev]e e>?quakes1 ( :i* ! mo/ t]rible occurr$ 9 ! ye> #aghc1 & aga9 9 #aije & #aijg4 ,!y h also be5 ! sc5e ( _m small] concussions4 ,illu/ration3 ,fig4 #ae4--;,e>?quake l9es 9 ! ,tyrrh5ian depression ,! bottom ( ! ,tyrrh5ian ,sea--betwe5 ,italy1 ,sicily1 & ,s>d9ia--has be5 l[]$ 9 r rec5t ages & is /ill s9k+4 ,we notice on ! map five dott$ l9es1 correspond+ to cracks 9 ! cru/ ( ! e>?4 ,^! l9es w\ld int]sect 9 ! volcanic di/rict ( ! ,lip>i ,isl&s4 ,we fur!r see a dott$ circul> arc correspond+ to a fissure :i* is reg>d$ z ! s\rce ( ! ,calabrian e>?quakes ( #aghc1 #aije1 & #aijg4 ,! e>?-cru/ behav$ some:at aft] ! mann] ( a w9d[pane :i* 0 bur/ by a heavy impact f a po9t correspond+ to ! ,isl& ( ,lip>i4 ,f ?is po9t radiate lies ( fracture1 & fragm5ts h be5 brok5 (f f ! e>?-cru/ by arc-%ap$ cracks4 ,! volcano ,etna is situat$ on ! int]section ( ! radial & circul> fissures4 ,illu/ration3 ,fig4 #af4--,seismogram record$ at ,%ide1 ,isle ( ,wight1 on ,augu/ #ca1 #ahih ,9 recognition ( ! high practical importance ( e>?quake obs]vations1 seismological /ations h 9 rec5t days be5 erect$ 9 _m localities4 ,at ^! obs]vatories ! e>?quakes are record$ by p5dulums ^: /yles draw l9es on tapes ( pap] mov$ by clock-"w4 ,z long z ! e>? is quiet ! drawn l9e is /raight4 ,:5 e>?quakes set 91 ! l9e passes into a wavy curve4 ,z long z ! movem5t ( ! pap] is sl[1 ! curve m]ely looks l a wid5$ /raight l9e4 ,! subjo9$ illu/ration 7,fig4 #af7 repres5ts a seismogram tak5 at ! /ation ( ,%ide1 on ! ,isle ( ,wight1 on ,augu/ #ca1 #ahih4 ,! e>?quake record$ orig9at$ 9 ! ,c5tre ,g1 9 ! ,indian ,ocean4 ,! orig9 has be5 d$uc$ f ! mom5ts ( arrival ( ! diff]5t waves at diff]5t /ations4 ,we notice on ! seismogram a fa9t wid5+ ( ! /raight l9e at #bj hrs4 #e m94 #b sec4 7#h hrs4 #e m94 #b sec4 ,p4,m474 ,! amplitude ( ! oscillations !n began to wid51 & ! heavie/ concussions 7 notic$ at #bj hrs4 #cf m94 #be sec41 & #bj hrs4 #db m94 #di sec41 aft] :i* ! amplitudes sl[ly decreas$ ) small] %ocks4 ,! fir/ %ock ( #bj hrs4 #e m94 #b sec4 is call$ ! prelim9>y tremor4 ,?is tremor passes ?r\gh ! int]ior ( ! e>? at a velocity ( propagation ( #i4b km4 7#e-c_/d miles7 p] second4 ,x w\ld require tw5ty-?ree m9utes to pass ?r\gh ! e>? along a diamet]4 ,! tremor is v feeble1 :i* is ascrib$ to ! extraord9>ily great friction *>act]i/ic ( ! /rongly heat$ gases :i* are conf9$ 9 ! int]ior ( ! e>?4 ,! pr9cipal viol5t %ock at #bj hrs4 #cf m94 #be sec4 0 caus$ by a wave travell+ ?r\gh ! solid cru/ ( ! e>?4 ,! int5sity ( ?is %ock is mu* less impair$ ?an t ( ! j-m5tion$ tremor1 & x travels ) ! small] velocity ( ab\t #c4d km4 7#b4a miles7 along ! e>?'s surface4 ,! velocity ( propagation ( concussion pulses has be5 calculat$ = a m\nta9 ( qu>tz1 9 :i* x w\ld be #c4f km4 7#b4b miles7 p] second1 v ne>ly ! same z ! la/-m5tion$ figure4 ,we %\ld expect ?is1 s9ce ! firm cru/ ( ! e>? consi/s ess5tially ( solid silicates--i4e41 comp\nds ( qu>tz end[$ ) simil> prop]ties4 ,measur$ at small di/ances f ! orig91 ! velocity ( propagation ( ! wave appe>s small]1 & ! fir/ prelim9>y tremor is frequ5tly n obs]v$4 ,! velocity may be dim9i%$ to #b km4 7#a-a_/d miles7 p] second4 ,! reason is t ! pulse p>tly describes a curve 9 ! m solid portions ( ! cru/1 & p>tly passes ?r\gh loos] /rata1 ?r\gh :i* ! wave travels at a mu* sl[] rate ?an 9 firm gr\nd2 = in/ance1 at #a4b km4 ?r\gh loose s&/ones1 at #a4d km4 ?r\gh ! wat] ( ! ocean1 & at #j4c km4 ?r\gh loose s&4 ,we recognize t x %\ld be possible to calculate ! di/ance betwe5 ! po9t ( obs]vation & ! orig9 ( ! e>?quake f ! data relat+ to ! arrivals ( ! fir/ prelim9>y tremor & ( ! pr9cipal %ock ( maximum amplitude4 ,! viol5t %ock is sometimes repeat$ aft] a c]ta9 "t1 ?\gh ) decreas$ int5sity4 ,x has (t5 be5 obs]v$ t ?is second>y1 less viol5t1 %ock seems to h travell$ all r\nd ! e>? via ! longe/ road betwe5 ! orig9 & ! po9t ( obs]vation1 j l "o portion ( ! a]ial waves 9 ! eruption ( ,krakatoa 7comp>e page #bg74 ,! velocity ( propagation ( ?is second>y %ock is ! same z t ( ! pr9cipal %ock4 ,milne has d$uc$ f 8 obs]vations t1 :5 ! l9e jo9+ ! orig9 ( ! e>?quake & ! po9t ( obs]vation does n at its l[e/ level desc5d deep] ?an #ej km4 bel[ ! surface ( ! e>?1 ! pulse w travel undivid$ ?r\gh ! solid cru/ ( ! e>?4 ,= ?is reason we e/imate ! ?ickness ( ! solid cru/ at #ej km4 ,! value is 9 almo/ p]fect agreem5t ) ! "o :i* we _h 7on page #af7 d]iv$ f ! increase ( temp]ature ) great] dep?s4 ,x %\ld fur!r be m5tion$1 p]haps1 t ! d5sity ( ! e>? 9 ! vic9ity has be5 det]m9$ f p5dulum obs]vation1 & t ?is d5sity seems to be r v>iable d[n to ! dep?s ( #ej or #fj km41 b to become m uni=m at great] dep?s4 ,^! #ej or #fj km4 7#ca or #cg miles7 w\ld belong to ! solid cru/ ( ! e>?4 ,! movem5t ( e>?quake %ocks ?r\gh ! e>? ?us tea*es u t ! solid e>?-cru/ _c be v ?ick1 & t ! core ( ! e>? is probably gase\s4 ,! simil> conclusions1 to :i* ^! v>i\s consid]ations _h l$ u1 may !re=e come v ne> ! tru?4 ,a c>eful /udy ( seismograms may1 we hope1 help u to le>n m ab\t ! c5tral portions ( ! e>?1 :i* at fir/ sight appe> to be absolutely inaccessible to sci5tific rese>*4 ,,ii ,,! ,,cele/ial ,,bodies1 ,,9 ,,p>ticul> ,,! ,,e>?1 ,,z ,,abodes ,,( ,,organisms ,!re is no m elevat+ spectacle ?an to contemplate ! sky ) its ?\s&s ( />s on a cle> night4 ,:5 we s5d our ?\ghts to ^? lights glitt]+ 9 inf9ite di/ance1 ! "q =ces itself ^u u1 :e!r !re are n out !re planets l our own t w su/a9 organic life4 ,h[ little int]e/ d we take 9 a b>r5 isl& ( ! ,arctic ,circle1 on :i* n a s+le plant w gr[1 comp>$ to an isl& 9 ! tropics :i* is teem+ ) life 9 its mo/ wond]ful v>iety6 ,! unkn[n worlds occupy our m9ds mu* m :5 we may fancy !m inhabit$ ?an :5 we h to reg>d !m z dead masses float+ ab\t 9 space4 ,we h to ask ourselves simil> que/ions ) reg>d to our own little planet1 ! e>?4 ,0 x always cov]$ ) v]dure1 or 0 x once /]ile & b>r58 ,& if t be s1 :at are ! conditions "u :i* ! e>? c fulfil its actual "p ( h>bor+ organic life8 ,t 8! e>? 0 )\t =m0 9 ! beg9n+ is unque/ionable4 ,x does n matt] :e!r we assume t x 0 once all ?r\gh an inc&esc5t liquid1 :i* may be ! mo/ probable assumption1 or t x 01 z ,locky] & ,m\lton ?9k1 =m$ by ! accumulation ( meteoric /ones :i* became inc&esc5t :5 arre/$ 9 _! motion4 ,we h se5 t ! e>? probably consi/s ( a mass ( gas encas$ )9 a %ell :i* is solid on ! outside & rema9s a viscid liquid on ! inn] side4 ,we presume ) good reason t ! e>? 0 orig9ally a mass ( gas sep>at$ f ! sun1 :i* is /ill 9 ! same /ate4 ,by radiation into cold space ! sph]e ( gas :i*1 on ! :ole1 w\ld behave z our sun does n[1 w\ld gradually lose its high temp]ature1 & f9ally a solid cru/ c\ld =m on its surface4 ,"l ,kelv9 has calculat$ t x w\ld n require m ?an "o hundr$ ye>s be=e ! temp]ature ( ?is cru/ w\ld s9k to #ajj4 ,suppos+1 ev51 t ,kelv9's calculations %\ld n q be confirm$1 we may yet ma9ta9 t n _m ?\s&s ( ye>s w\ld h elaps$ f ! "t :5 ! e>? assum$ its fir/ cru/ at ab\t #ajjj till ! age :5 ?is temp]ature _h fall5 bel[ #ajj 7#bab ,f474 ,liv+ be+s c]ta9ly c\ld n exi/ s long1 s9ce ! album5 ( ! cells w\ld at once coagulate at ! temp]ature ( boil+ wat]1 l ! :ite ( an egg4 ,yet x has be5 report$ t "s ( ! hot spr+s ( ,new ,zeal& conta9 alg1 al?\gh at a temp]ature ( ov] #hj4 ,:5 ,i w5t to ,yell[/one ,p>k to inquire into ! correctness ( ?is /atem5t1 ,i f\nd t ! alg exi/$ only at ! edge ( ! hot spr+s1 :]e ! temp]ature did n exce$ #fj 7#adj ,f474 ,! fam\s ,am]ican physiologi/ ,loeb /ates t we d n meet ) alg 9 hot spr+s at temp]atures above #ee4 ,s9ce1 n[1 ! temp]ature ( ! e>?-cru/ w\ld mu* m quickly s9k f #ajj to #ee ?an x _h fall5 f #ajjj to #ajj1 we may imag9e t only a few ?\s&s ( ye>s may h int]v5$ betwe5 ! =mation ( ! fir/ cru/ ( ! e>? & ! cool+ d[n to a temp]ature su* z w\ld su/a9 life4 ,s9ce t "t ! temp]ature has probably nev] be5 s l[ t ! l>g] portion ( ! e>?'s surface w\ld n h be5 able to support organisms1 al?\gh !re h be5 sev]al glacial ages 9 :i* ! arctic di/ricts inaccessible to life mu/ h ext5d$ mu* f>!r ?an at pres5t4 ,! ocean w also h be5 free ( ice ov] mu* ! greate/ portion ( its surface at all times1 & may !re=e h be5 inhabit$ by organisms 9 all ages4 ,! int]ior ( ! e>? cools cont9ually1 ?\gh sl[ly1 because heat passes f ! inn]1 w>m] portions to ! o!r1 cool] portions ?r\gh ! cru/ ( ! e>?4 ,! e>? is able to s]ve z ! abode ( liv+ be+s because its out] portions are cool$ to a suitable temp]ature 7bel[ #ee7 by radiation1 & because ! cool+ does n proce$ s f> t ! op5 sea w\ld cont9ually be froz5 ov]1 & t ! temp]ature on ! ,cont95t w\ld always rema9 bel[ freez+-po9t4 ,we owe ?is favorable int]m$iate /age to ! fact t ! radiation f ! sun balances ! loss ( heat by radiation into space1 & t x is capable ( ma9ta9+ ! great] portion ( ! surface ( ! e>? at a temp]ature above ! freez+-po9t ( wat]4 ,! temp]ature condition+ life on a planet is !re=e ma9ta9$ only because1 on ! "o side1 light & heat are receiv$ by radiation f ! sun 9 suffici5t quantities1 :ile on ! o!r side an equival5t radiation ( heat takes place into space4 ,if ! heat ga9 & ! heat loss 7 n to balance ea* o!r1 ! t]m ( suitable conditions w\ld n la/ long4 ,! temp]ature ( ! e>?-cru/ c\ld s9k 9 a few hundr$s or ?\s&s ( ye>s f #ajjj to #ajj1 because :5 ! e>? 0 at ?is high temp]ature its radiation into space pr$om9at$ ov] ! radiation receiv$ f ! sun4 ,on ! o!r h&1 ab\t a hundr$ million ye>s h pass$1 accord+ to ,joly1 s9ce ! age :5 ! ocean orig9at$4 ,! temp]ature ( ! e>?1 !re=e1 requir$ ?is long space ( "t 9 ord] to cool d[n f #cfe 7at :i* temp]ature wat] vapor c fir/ be cond5s$ to liquid wat]7 to its pres5t temp]ature4 ,! cool+ aft]w>ds proce$$ at a sl[] rate1 because ! diff]5ce betwe5 ! radiations inw>d & outw>d 0 less5$ ) ! dim9i%+ temp]ature ( ! e>?4 ,v>i\s me?ods h be5 appli$ 9 e/imat+ ^! p]iods4 ,joly bas$ 8 e/imate on ! p]c5tage ( salt 9 ! sea & 9 ! riv]s4 ,if we calculate h[ mu* salt !re is 9 ! sea1 & h[ mu* salt ! riv]s c supply to x 9 ! c\rse ( a ye>1 we arrive at ! result t ! quantity ( salt n[ /or$ 9 ! ocean might h be5 suppli$ 9 ab\t a hundr$ million ye>s4 ,we arrive at /ill high] numb]s :5 we calculate ! "t :i* mu/ h elaps$ dur+ ! deposition ( all ! /ratifi$ & s$im5t>y lay]s4 ,sir ,ar*ibald ,geikie e/imates ! total ?ickness ( ^? /rata1 suppos+ !m to h be5 undi/urb$1 at #cj1jjj m4 7ne>ly #bj miles74 ,he concludes1 fur!r1 f ! exam9ation ( m rec5t /rata1 t e /ratum "o metre 9 ?ickness mu/ h requir$ f #cjjj to #bj1jjj ye>s = its =mation4 ,we %\ld1 !re=e1 h to all[ a space ( f n9ety to six hundr$ million ye>s = ! deposition ( all ! s$im5t>y /rata4 ,! ,f9ni% geologi/ ,s$]holm ev5 fixes ! "t at a ?\s& million ye>s4 ,ano!r me?od aga9 />ts f ! consid]ation t1 :ile ! temp]ature ( ! surface ( ! e>? rema9s fairly /eady ow+ to ! heat ex*ange betwe5 sol> radiation & t]re/rial radiation into space1 ! int]ior ( ! e>? mu/ h %runk ) ! cool+4 ,h[ f> ?is %r9kage ext5ds we may e/imate f ! =mation ( ! m\nta9 *a9s :i*1 accord+ to ,rudzki1 cov] #a4f p] c5t4 ( ! e>?'s surface4 ,! e>?'s radius %\ld consequ5tly h contract$ by ab\t #j4h p] c5t41 correspond+ to a cool+ ?r\gh ab\t #cjj1 :i* w\ld require two ?\s& million ye>s4 ,q rec5tly ! r5[n$ physical *emi/ ,ru!r=d has exp\nd$ a mo/ orig9al me?od ( e/imat+ ! age ( m9]als4 ,uranium & ?orium are suppos$ to produce helium by _! sl[ dissociation1 & we "k h[ mu* helium is produc$ f a c]ta9 quantity ( uranium or ?orium 9 a ye>4 ,n[ ,ramsay has det]m9$ ! p]c5tage ( helium 9 ! uranium m9]al f]gusonite & 9 ?orianite4 ,ru!r=d !n calculates ! "t :i* w\ld h pass$ s9ce ! =mation ( ^! m9]als4 ,he dem&s at lea/ f\r hundr$ million ye>s1 8= v probably "s helium has escap$ f ! m9]als dur+ t "t40 ,al?\gh ?is e/imate is v unc]ta91 x is int]e/+ to f9d t x leads to an age = ! solid e>?-cru/ ( ! same ord] ( magnitude z ! o!r me?ods4 ,dur+ ?is :ole epo* ( almo/ inconceivable l5g? ( betwe5 "o hundr$ million & two ?\s& million ye>s1 organisms h exi/$ on ! surface ( ! e>? & 9 ! sea :i* d n diff] s v mu* f ^? n[ alive4 ,! temp]ature ( ! surface may h be5 high] ?an x is at pres5t2 b ! diff]5ce _c be v great1 & w am\nt to #bj ,c5t4 7#cf ,f47 at ! highe/4 ,! actual mean temp]ature ( ! surface ( ! e>? is #af ,c5t4 7#fa ,f474 ,x v>ies f ab\t -#bj ,c5t4 7-#d ,f47 at ! ,nor? ,pole1 & -#aj ,c5t4 7#ad ,f47 at ! ,s\? ,pole to #bf ,c5t4 7#gi ,f47 9 ! tropical zone4 ,! ma9 diff]5ce betwe5 ! temp]atures ( ! e>?'s surface 9 ! mo/ remote p]iod f :i* fossils are extant & ! actual /ate r seems to be t ! diff]5t zones ( ! e>? are n[ *>act]iz$ by unequal temp]atures1 :ile 9 ! remote epo*s ! heat 0 almo/ uni=mly di/ribut$ ov] ! :ole e>?4 ,! condition = ?is prolong$1 almo/ /ation>y /ate 0 t ! ga9 ( heat ( ! e>?'s surface by radiation f ! sun & ! loss ( heat by radiation into space ne>ly balanc$ ea* o!r4 ,t ! repl5i%+ supply by radiation f an int5sely hot body--9 our case ! sun--is indisp5sable = ! exi/5ce ( life w be evid5t to ev]ybody4 ,n ev]ybody may1 h[ev]1 h consid]$ t ! loss ( heat into cold space or into cold] surr\nd+s is j z indisp5sable4 ,to "s p1 inde$1 ! assumption t ! e>? z well z ! sun %\ld wa/e ! l>ge/ portions ( _! vital heat z radiation into cold space appe>s s unsatisfactory t !y pref] to believe radiation to be conf9$ to radiation betwe5 cele/ial bodies2 !re is no radiation into space1 9 _! op9ion4 ,all ! sol> heat w\ld ?us b5efit ! planets & ! moons 9 ! sol> sy/em1 & only a vani%+ portion ( x w\ld fall ^u ! fix$ />s1 because _! visual angles are s small4 ,if t 7 really correct1 ! temp]ature ( ! planets w\ld rise at a rapid rate until x became almo/ equal to t ( ! sun1 & all life w\ld become impossible4 ,we are !re=e con/ra9$ to admit t 8?+s are be/ z !y are10 al?\gh ! great wa/e ( sol> heat c]ta9ly weak5s ! sol> en]gy4 ,! op9ion t all ! sol> heat radiat$ into inf9ite space is wa/$1 />ts moreov] f a hypo!sis :i* is n prov$1 & :i* is highly improbable--namely1 t only an extremely small portion ( ! sky is cov]$ ) cele/ial bodies4 ,t might c]ta9ly be correct if we assum$1 z has =m]ly be5 done1 t ! majority ( ! cele/ial bodies mu/ be lum9\s4 ,we d n possess1 h[ev]1 any reliable k ( ! numb] & size ( ! d>k cele/ial bodies4 ,9 ord] to acc\nt = ! obs]v$ movem5ts ( diff]5t />s1 x has be5 ?\ght t !re mu/ be 9 ! neighborhood ( "s ( !m d>k />s ( enorm\s size ^: masses w\ld surpass ! mass ( our sun1 or1 at lea/1 be equal to x4 ,b ! l>ge/ numb] ( ! d>k cele/ial bodies :i* hide ! rays f ! />s beh9d !m probably consi/ ( small] p>ticles1 su* z we obs]ve 9 meteors & 9 comets1 & to a l>ge ext5t ( s-call$ cosmical du/4 ,! obs]vations ( lat] ye>s1 by ! aid ( mo/ p[]ful in/rum5ts1 h %[n t s-call$ nebul & nebul\s />s ab\nd ?r\gh\t ! heav5s4 ,9 _! int]ior we %\ld probably f9d accumulations ( d>k masses4 ,! light int5sity ( mo/ ( ! nebul is1 moreov]1 f> too weak to p]mit ( _! be+ p]ceiv$4 ,we h1 !re=e1 to imag9e t !re are bodies all ?r\gh inf9ite space1 & ab\t z num]\s z !y are 9 ! imm$iate neighborhood ( our sol> sy/em4 ,?us e ray f ! sun1 ( :atev] direction1 w\ld f9ally hit ^u "s cele/ial body1 & no?+ w\ld be lo/ ( ! sol> radiation1 nor ( ! /ell> radiation4 ,z reg>ds ! radiation-heat ex*ange1 ! e>? might be lik5$ to a /eam-eng9e4 ,9 ord] t ! /eam-eng9e %all p]=m useful "w1 x is necess>y n only t ! eng9e be suppli$ ) heat ( high temp]ature f a furnace & a boil]1 b also t ! eng9e be able to give its heat up aga9 to a heat res]voir ( l[] temp]ature--a cond5s] or cool]4 ,x is only by transf]r+ heat f a body ( high] temp]ature to ano!r body ( l[] temp]ature t ! eng9e c d "w4 ,9 a simil> way no "w c be done on ! e>?1 & no life c exi/1 unless heat be conf]r$ by ! int]m$iation ( ! e>? f a hot body1 ! sun1 to ! cold] surr\nd+s ( univ]sal space--i4e41 to ! cold cele/ial bodies 9 x4 ,to a c]ta9 ext5t ! temp]ature ( ! e>?'s surface1 z we %all pres5tly see1 is conditional by ! prop]ties ( ! atmosph]e surr\nd+ x1 & p>ticul>ly by ! p]meability ( ! latt] = ! rays ( heat4 ,if ! e>? did n possess an atmosph]e1 or if ?is atmosph]e 7 p]fectly dia!rmal--i4e41 p]vi\s to heat radiations--we %\ld be able to calculate ! mean temp]ature ( ! e>?'s surface1 giv5 ! int5sity ( ! sol> radiation1 f ,/efan's law ( ! dep5d5ce ( heat radiation on its temp]ature4 ,/>t+ f ! n improbable assumption t1 at a mean di/ance ( ! e>? f ! sun1 ! sol> rays w\ld s5d #b4e gramme-calories p] m9ute to a body ( cross section ( #a sq4 c5timetre at "r angles to ! rays ( ! sun1 ,*ri/ians5 has calculat$ ! mean temp]atures ( ! surfaces ( ! v>i\s planets4 ,! foll[+ table gives 8 figures1 & also ! mean di/ances ( ! planets f ! sun1 9 units ( ! mean di/ance ( ! e>? f ! sun1 #adi4e million km4 7ne>ly #ic million miles73 ,radius ,mass ,mean ,mean ,d5sity ,planet di/ance temp]ature accord+ ,accord+ to ,see to ,see ,m]cury #j4cda #j4jbbd #j4ci #agh7ccb7 #j4efd ,v5us #j4iee #j4hae #j4gb #fe #j4icf ,e>? #a #a #a #f4e #a ,moon #j4bgc #j4jabbh #a #f4e7aje7 #j4fjd ,m>s #j4ec #j4ajgg #a4eb - #cg #j4gbi ,jupit] #aa4ac #cag4g #e4b - #adg #j4bcj ,saturn #i4ce #ie4a #i4ee - #ahj #j4aaf ,uranus #c4ce #ad4f #ai4bb - #bjg #j4chh ,neptune #c4dc #ag4b #cj4ab - #bba #j4dbi ,sun #aji4a #ccb1gej #j #fbjj #j4bef ,9 ! case ( ,m]cury1 ,i h add$ ano!r figure1 #ccb4 ,m]cury always turns ! same side to ! sun1 & ! hotte/ po9t ( ?is side w\ld rea* a temp]ature ( #cig2 its mean temp]ature1 accord+ to my calculation1 is #ccb1 :ile ! o!r side1 turn$ away f ! sun1 _c be at a temp]ature mu* above absolute z]o1 -#bgc4 ,i h made a simil> calculation = ! moon1 :i* turns s sl[ly ab\t its axis 7once 9 tw5ty-sev5 days7 t ! temp]ature on ! side illum9at$ by ! sun rema9s almo/ z high 7#ajf7 z if ! moon 7 always turn+ ! same face to ! sun4 ,! hotte/ po9t ( ?is surface w\ld atta9 a temp]ature ( #aej1 :ile ! poles ( ! moon & t "p ( ! o!r side :i* rema9s longe/ )\t illum9ation c1 aga91 n be mu* above absolute z]o temp]ature4 ,?is e/imate is 9 fair agreem5t ) ! measurem5ts made ( ! lun> radiation & ! temp]ature e/imate bas$ ^u x4 ,! fir/ measurem5t ( ?is k9d 0 made by ! ,e>l ( ,rosse4 ,he asc]ta9$ t ! moon disk z illum9at$ by ! sun--t is to say1 ! full moon--w\ld radiate z mu* heat z a black body ( ! temp]ature #aaj ,c5t4 7#bcj ,f474 ,a lat] measurem5t by ! ,am]ican ,v seems to indicate t ! hotte/ po9t ( ! moon is at ab\t #ahj1 :i* w\ld be #cj high] ?an my e/imate4 ,9 ! cases ( ! moon & ( ,m]cury1 :i* d n possess any atmosph]e to speak (1 ?is calculation may v fairly agree ) ! actual /ate ( affairs4 ,! temp]ature ( ! planet ,v5us w\ld be ab\t #fe ,c5t4 7#adi ,f47 if its atmosph]e 7 p]fectly transp>5t4 ,we "k1 h[ev]1 t d5se cl\ds1 probably ( wat] drops1 are float+ 9 ! atmosph]e ( ?is planet1 prev5t+ u f see+ its l& & wat] surfaces4 ,accord+ to ! det]m9ations made by ,zlln] & o!rs1 ,v5us w\ld reflect n less ?an #gf p] c5t4 ( ! incid5t light ( ! sun1 & ! planet w\ld ?us be z :ite z a sn[-ball4 ,! rays ( heat are n reflect$ to ! same ext5t4 ,we may e/imate t ! portion ( heat absorb$ by ! planet is ab\t half ! incid5t heat4 ,! temp]ature ( ,v5us w !re=e be r$uc$ consid]ably1 b x is p>tly augm5t$ aga9 by ! protective action ( ?is atmosph]e4 ,! mean temp]ature ( ,v5us may1 h5ce1 n diff] mu* f ! calculat$ temp]ature1 & may am\nt to ab\t #dj 7#ajd ,f474 ,"u ^! circum/ances ! assumption w\ld appe> plausible t a v consid]able portion ( ! surface ( ,v5us1 & p>ticul>ly ! di/ricts ab\t ! poles1 w\ld be favorable to organic life4 ,pass+ to ! e>?1 we f9d t ! temp]ature-r$uc+ influ5ce ( ! cl\ds mu/ be /rong4 ,!y protect ab\t half ( ! e>?'s surface 7#eb p] c5t47 f sol> radiation4 ,b ev5 ) a p]fectly cle> sky1 n all ! light f ! sun really rea*es ! e>?'s surface2 = f9ely di/ribut$ du/ is float+ ev5 9 ! pure/ air4 ,i h e/imat$ t ?is du/ w\ld probably absorb #ag p] c5t4 ( ! sol> heat4 ,cl\ds & du/ w\ld !re=e toge!r deprive ! e>? ( #cd p] c5t4 ( ! heat s5t to x1 :i* w\ld lead to a r$uction ( ! temp]ature by ab\t #bh4 ,du/ & ! wat]-bubbles 9 ! cl\ds also prev5t ! radiation ( heat f ! e>?1 s t ! total loss ( heat to be *>g$ to cl\ds & du/ w am\nt to ab\t #bj 7#cf ,f474 ,x has n[ be5 asc]ta9$ t ! mean temp]ature ( ! e>? is #af 7#fa ,f471 in/ead ( ! calculat$ #f4e 7#dc4g ,f474 ,d$uct+ ! #bj due to ! influ5ce ( du/ & cl\ds1 we obta9 -#ad 7#g ,f471 & ! obs]v$ temp]ature w\ld !re=e be high] ?an ! calculat$ by no less ?an #cj 7#ed ,f474 ,! discrepancy is expla9$ by ! heat-protect+ action ( ! gases conta9$ 9 ! atmosph]e1 to :i* we %all pres5tly ref] 7page #ea74 ,!re are b few cl\ds on ,m>s4 ,?is planet is end[$ ) an atmosph]e ( extreme transp>5cy1 & %\ld !re=e h a high temp]ature4 ,in/ead ( ! temp]ature ( -#cg 7#ce ,f471 calculat$1 ! mean temp]ature seems to be #aj 7#ej ,f474 ,dur+ ! w9t] l>ge :ite masses1 evid5tly sn[1 collect on ! poles ( ,m>s1 :i* rapidly melt away 9 spr+ & *ange into wat] t appe>s d>k to u4 ,sometimes ! sn[-caps on ! poles ( ,m>s disappe> entirely dur+ ! ,m>s summ]2 ?is nev] happ5s on our t]re/rial poles4 ,! mean temp]ature ( ,m>s mu/ !re=e be above z]o1 probably ab\t #aj4 ,organic life may v probably ?rive1 !re=e1 on ,m>s4 ,x is1 h[ev]1 r sangu9e to jump at ! conclusion t ! s-call$ canals ( ,m>s prove its be+ inhabit$ by intellig5t be+s4 ,_m p reg>d ! 8canals0 z optical illusions2 ,l[ell's photographs1 h[ev]1 d n ju/ify ?is op9ion4 ,z reg>ds ! o!r l>ge planets1 ! temp]atures :i* we h calculat$ = !m are v l[4 ,?is calculation is1 h[ev]1 r illusory1 because ^! planets probably d n possess any solid or liquid surface1 b consi/ altoge!r ( gases4 ,_! d5sities1 at lea/1 po9t 9 ?is direction4 ,9 ! case ( ! inn] planets1 ,m>s & our moon includ$1 ! d5sity is r less ?an t ( ! e>?4 ,m]cury /&s la/ among !m1 ) its specific gravity ( #j4efd4 ,!re foll[s a great drop 9 ! specific gravities ( ! out] l>ge planets4 ,saturn1 ) a d5sity ( #j4aaf1 is la/ 9 ?is ord]2 ! d5sities ( ! two out]mo/ planets lie some:at high]--by #j4c or #j4d ab\t--b ^! la/ data are v unc]ta94 ,yet ^! figures are ( ! same ord] ( magnitude z t assum$ = ! sun--#j4be--;& we believe t ! sun1 ap>t f ! small cl\ds1 is :olly a gase\s body4 ,x is !re=e probable t ! out] planets1 includ+ ,jupit]1 w also be gase\s & be surr\nd$ by d5se veils ( cl\ds :i* prev5t our look+ d[n into _! int]ior4 ,t view w\ld cont5d aga9/ ! idea t ^! planets c h>bor any liv+ be+s4 ,we c\ld r imag9e _! moons to be inhabit$4 ,if ^! moons receiv$ no heat f _! planets1 !y w\ld assume ! above-/at$ temp]atures ( _! c5tral bodies4 ,look$ at f our moon1 ! e>? appe>s "u a visual angle1 #c4g times z l>ge z t ( ! sun4 ,z ! temp]ature ( ! sun has1 f its radiation1 be5 e/imat$ at #fbjj ,c5t41 or #fejj absolute1 ! moon w\ld receive z mu* heat f ! e>? z f ! sun1 if ! e>? _h a temp]ature ( ab\t #cajj ,c5t41 or #cchj absolute4 ,:5 ! fir/ cl\ds ( wat] vapor 7 be+ =m$ 9 ! t]re/rial atmosph]e1 ! e>?'s temp]ature 0 ab\t #cfj1 & ! radiation f ! e>? to ! moon only ab\t #a4be-?\s&? ( t ( ! sun4 ,! pres5t radiation f ! e>? does n ev5 atta9 "o-tw5tie? ( ?is value4 ,x is ?us manife/ t ! radiation f ! e>? does n play any "p 9 ! !rmal h\sehold ( ! moon4 ,! relations w\ld be q diff]5t if ! e>? _h ! #aa4f times great] diamet] ( ,jupit]1 or ! diamet] ( ,saturn1 :i* is #i4c times great] ?an its own4 ,! radiation f ! e>? to ! moon w\ld !n make up ab\t a six? or a n9? ( ! actual sol> radiation1 tak+ ! temp]ature ( ! e>?'s surface at #cfj4 ,we c easily calculate1 fur!r1 t ,jupit] & ,saturn w\ld radiate z mu* heat aga9/ a moon at a di/ance ( #bdj1jjj or #aia1jjj km4 respectively 7s9ce ! di/ance ( ! moon f ! e>? am\nts to #chd1jjj km47 z ! sun s5ds to ,m>s--tak+ ! temp]ature ( ^? planets at #cfj ,c5t4 ,n[ we f9d1 ne> ,jupit] z well z ne> ,saturn1 moons at ! di/ances ( #abf1jjj & #ahf1jjj km4 respectively1 :i* are small] ?an ^? m5tion$1 & x is n inconceivable t ^! moons receive f _! c5tral bodies suffici5t heat to r5d] life possible1 provid$ t !y be envelop$ by a heat-absorb+ atmosph]e4 ,! conditions appe> to be less favorable = ! inn]mo/ satellites ( ,jupit] & ,saturn4 ,:5 _! planets are %9+ at ! maximum brilliancy1 _! light int5sity is only a six? or a n9? ( ! sol> light int5sity1 :i* ^u ^! satellites is itself only "o-tw5ty-sev5? or "o-n9etie? ( ! int5sity on ! e>?4 ,dur+ ! inc&esc5ce epo* ( ^! planets _! moons w c]ta9ly = "s "t h be5 suitable = ! developm5t ( life4 ,t ! atmosph]ic envelopes limit ! heat losses f ! planets _h be5 sugge/$ ab\t #ahjj by ! great ,fr5* physici/ ,f\ri]4 ,8 ideas 7 fur!r develop$ aft]w>ds by ,p\illet & ,tyndall4 ,_! !ory has be5 /yl$ ! hot-h\se !ory1 because !y ?\ght t ! atmosph]e act$ aft] ! mann] ( ! glass panes ( hot-h\ses4 ,glass possesses ! prop]ty ( be+ transp>5t to heat rays ( small wave l5g?s belong+ to ! visible spectrum2 b x is n transp>5t to d>k heat rays1 su*1 = in/ance1 z are s5t out by a heat$ furnace or by a hot lump ( e>?4 ,! heat rays ( ! sun n[ are to a l>ge ext5t ( ! visible1 bright k9d4 ,!y p5etrate ?r\gh ! glass ( ! hot-h\se & heat ! e>? "u ! glass4 ,! radiation f ! e>?1 on ! o!r h&1 is d>k & _c pass back ?r\gh ! glass1 :i* ?us /ops any losses ( heat1 j z an ov]coat protects ! body aga9/ too /rong a loss ( heat by radiation4 ,langley made an exp]im5t ) a box1 :i* he pack$ ) cotton-wool to r$uce loss by radiation1 & :i* he provid$1 on ! side turn$ t[>ds ! sun1 ) a d\ble glass pane4 ,he obs]v$ t ! temp]ature rose to #aac 7#bce ,f471 :ile ! !rmomet] only m>k$ #ad or #ae 7#eg or #ei ,f47 9 ! %ade4 ,?is exp]im5t 0 conduct$ on ,pike's ,peak1 9 ,colorado1 at an altitude ( #dbjj m4 7#ac1hjj ft471 on ,septemb] #i1 #ahha1 at #a hr4 #d m94 ,p4,m41 & !re=e at a p>ticul>ly int5se sol> radiation4 ,f\ri] & ,p\illet n[ ?\ght t ! atmosph]e ( our e>? %\ld be end[$ ) prop]ties resembl+ ^? ( glass1 z reg>ds p]meability ( heat4 ,tyndall lat] prov$ ?is assumption to be correct4 ,! *ief invisible con/itu5ts ( ! air :i* p>ticipate 9 ?is effect are wat] vapor1 :i* is always f\nd 9 a c]ta9 quantity 9 ! air1 & c>bonic acid1 also ozone & hydroc>bons4 ,^! latt] occur 9 su* small quantities t no all[ance has be5 made = !m s f> 9 ! calculations4 ,( late1 h[ev]1 we h be5 suppli$ ) v c>eful obs]vations on ! p]meability to heat ( c>bonic acid & ( wat] vapor4 ,) ! help ( ^! data ,i h calculat$ t if ! atmosph]e 7 depriv$ ( all its c>bonic acid--( :i* x conta9s only #j4jc p] c5t4 by volume--! temp]ature ( ! e>?'s surface w\ld fall by ab\t #ba4 ,?is l[]+ ( ! temp]ature w\ld dim9i% ! am\nt ( wat] vapor 9 ! atmosph]e1 & w\ld cause a fur!r almo/ equally /rong fall ( temp]ature4 ,! examples1 s f> z !y g1 demon/rate t comp>atively unimportant v>iations 9 ! composition ( ! air h a v great influ5ce4 ,if ! quantity ( c>bonic acid 9 ! air %\ld s9k to "o-half its pres5t p]c5tage1 ! temp]ature w\ld fall by ab\t #d2 a dim9ution to "o-qu>t] w\ld r$uce ! temp]ature by #h4 ,on ! o!r h&1 any d\bl+ ( ! p]c5tage ( c>bon dioxide 9 ! air w\ld raise ! temp]ature ( ! e>?'s surface by #d2 & if ! c>bon dioxide 7 increas$ f\rfold1 ! temp]ature w\ld rise by #h4 ,fur!r1 a dim9ution ( ! c>bonic acid p]c5tage w\ld acc5tuate ! temp]ature diff]5ces betwe5 ! diff]5t portions ( ! e>?1 :ile an increase 9 ?is p]c5tage w\ld t5d to equalize ! temp]ature4 ,! "q1 h[ev]1 is :e!r any su* temp]ature fluctuations h really be5 obs]v$ on ! surface ( ! e>?4 ,! geologi/s w\ld answ]3 yes4 ,our hi/orical era 0 prec$$ by a p]iod 9 :i* ! mean temp]ature 0 by #b 7#c4f ,f47 high] ?an at pres5t4 ,we recognize ?is f ! =m] di/ribution ( ! ord9>y hazel-nut & ( ! wat]-nut 7,trapa natans74 ,fossil nuts ( ^! two species h be5 f\nd 9 localities :]e ! plants c\ld n ?rive 9 ! pres5t climate4 ,?is age1 aga91 0 prec$$ by an age :i*1 we are pretty c]ta91 drove ! inhabitants ( nor!rn ,europe f _! old abodes4 ,! glacial age mu/ h be5 divid$ into sev]al p]iods1 alt]nat+ ) int]vals ( mild] climates1 ! s-call$ int]-glacial p]iods4 ,! space ( "t :i* is *>act]iz$ by ^! glacial p]iods1 :5 ! temp]ature--accord+ to measurem5ts bas$ ^u ! /udy ( ! spread+ ( glaci]s 9 ! ,alps--mu/ h be5 ab\t #e 7#h ,f47 l[] ?an n[1 has be5 e/imat$ by geologi/s at n less ?an #ajj1jjj ye>s4 ,?is epo* 0 prec$$ by a w>m] age1 9 :i* ! temp]ature1 to judge f fossiliz$ plants ( ^? days1 mu/ at times h be5 by #h or #i 7#ad or #af ,f47 high] ?an at pres5t1 &1 moreov]1 mu* m uni=mly di/ribut$ ov] ! :ole e>? 7,eoc5e74 ,pron\nc$ fluctuations ( ?is k9d 9 ! climate h also occurr$ 9 =m] geological p]iods4 ,are we n[ ju/ifi$ 9 suppos+ t ! p]c5tage ( c>bon dioxide 9 ! air has v>i$ to an ext5t suffici5t to acc\nt = ! temp]ature *anges8 ,?is "q has be5 answ]$ 9 ! affirmative by ,hgbom1 &1 9 lat] times1 by ,/ev5son4 ,! actual p]c5tage ( c>bonic acid 9 ! air is s insignificant t ! annual combu/ion ( coal1 :i* has n[ 7#aijd7 ris5 to ab\t #ijj million tons & is rapidly increas+1#c c>ries ab\t "o-sev5-hundr$? "p ( its p]c5tage ( c>bon dioxide to ! atmosph]e4 ,al?\gh ! sea1 by absorb+ c>bonic acid1 acts z a regulator ( huge capacity1 :i* takes up ab\t five-six?s ( ! produc$ c>bonic acid1 we yet recognize t ! slight p]c5tage ( c>bonic acid 9 ! atmosph]e may by ! advances ( indu/ry be *ang$ to a noticeable degree 9 ! c\rse ( a few c5turies4 ,t w\ld imply t !re is no real /ability 9 ! p]c5tage ( c>bon dioxide 9 ! air1 :i* is probably subject to consid]able fluctuations 9 ! c\rse ( "t4 ,footnote #c3 ,x am\nt$ 9 #ahij to #eaj million tons2 9 #ahid1 to #eej2 9 #ahii1 to #fij2 & 9 #aijd1 to #hij million tons4 ,volcanism is ! natural process by :i* ! greate/ am\nt ( c>bonic acid is suppli$ to ! air4 ,l>ge quantities ( gases orig9at+ 9 ! int]ior ( ! e>? are eject$ ?r\gh ! crat]s ( ! volcanoes4 ,^! gases consi/ mo/ly ( /eam & ( c>bon dioxide1 :i* h be5 lib]at$ dur+ ! sl[ cool+ ( ! silicates 9 ! int]ior ( ! e>?4 ,! volcanic ph5om5a h be5 ( v unequal int5sity 9 ! diff]5t phases ( ! hi/ory ( ! e>?1 & we h reason to surmise t ! p]c5tage ( c>bon dioxide 9 ! air 0 consid]ably great] dur+ p]iods ( /rong volcanic activity ?an x is n[1 & small] 9 quiet] p]iods4 ,pr(essor ,fre*1 ( ,breslau1 has attempt$ to demon/rate t ?is w\ld be 9 accordance ) geological exp]i5ce1 because /rongly volcanic p]iods are di/+ui%$ by w>m climates1 & p]iods ( feeble volcanic int5sity by cold climates4 ,! ice age 9 p>ticul> 0 *>act]iz$ by a ne>ly complete cessation ( volcanism1 & ! two p]iods at ! comm5cem5t & at ! middle ( ! ,t]ti>y age 7,eoc5e & ,mioc5e7 :i* %[$ high temp]atures 7 also m>k$ by an extraord9>ily develop$ volcanic activity4 ,?is p>allelism c be trac$ back into m remote epo*s4 ,x may possibly be a matt] ( surprise t ! p]c5tage ( c>bon dioxide 9 ! atmosph]e %\ld n con/antly be increas$1 s9ce volcanism is always p\r+ out m c>bon dioxide into our atmosph]e4 ,!re is1 h[ev]1 "o factor :i* always t5ds to r$uce ! c>bon dioxide ( ! air1 & t is ! wea!r+ ( m9]als4 ,! rocks :i* 7 fir/ =m$ by ! congelation ( ! volcanic masses 7! s-call$ magma7 consi/ ( comp\nds ( silicic acid ) alum9a1 lime1 magnesia1 "s iron & sodium4 ,^! rocks 7 gradually decompos$ by ! c>bonic acid conta9$ 9 ! air & 9 ! wat]1 & x 0 especially ! lime1 ! magnesia1 & ! alkalies1 &1 9 "s measure also ! iron1 :i* =m$ soluble c>bonates4 ,^! c>bonates 7 c>ri$ by ! riv]s d[n into ! seas4 ,!re lime & magnesia 7 secret$ by ! animals & by ! alg1 & _! c>bonic acid became /or$ up 9 ! s$im5t>y /rata4 ,hgbom e/imates t ! lime/ones & dolomites conta9 at lea/ #be1jjj times m c>bonic acid ?an our atmosph]e4 ,*amb]l9 has arriv$ at ne>ly ! same figure--f #bj1jjj to #cj1jjj2 he does n all[ = ! precambrian lime/ones4 ,^! e/imates are mo/ likely f> too l[4 ,all ! c>bonic acid t is /or$ up 9 s$im5t>y /rata mu/ h pass$ ?r\gh ! atmosph]e4 ,ano!r process :i* )draws c>bonic acid f ! air is ! assimilation ( plants4 ,plants absorb c>bonic acid "u secretion ( c>bon comp\nds & "u exhalation ( oxyg54 ,l ! wea!r+1 ! assimilation increases ) ! p]c5tage ( c>bonic acid4 ,! ,poli% botani/ ,e4 ,godlewski %[$ z e>ly z #ahgb t v>i\s plants 7he /udi$ ,typha latifolia & ,glyc]ia spectabilus ) p>ticul> c>e7 absorb f ! air an am\nt ( c>bonic acid :i* increases proportionally ) ! p]c5tage ( c>bonic acid 9 ! atmosph]e up to #a p] c5t41 & t ! assimilation !n atta9s1 9 ! =m] plant1 a maximum at #f p] c5t41 & 9 ! latt] plant at #i p] c5t4 ,! assimilation aft]w>ds dim9i%es if ! c>bonic acid p]c5tage is fur!r augm5t$4 ,if1 !re=e1 ! p]c5tage ( c>bon dioxide be d\bl$1 ! absorption by ! plants w\ld also be d\bl$4 ,if1 at ! same "t1 ! temp]ature rises by #d1 ! vitality w increase 9 ! ratio ( #a3 #a4e1 s t ! d\bl+ ( ! c>bon dioxide p]c5tage w lead to an increase 9 ! absorption ( c>bonic acid by ! plant approximately 9 ! ratio ( #a3 #c4 ,! same may be assum$ to hold = ! dep5d5ce ( ! wea!r+ ^u ! atmosph]ic p]c5tage ( c>bonic acid4 ,an increase ( ! c>bon dioxide p]c5tage to d\ble its am\nt may h5ce be able to raise ! int5sity ( vegetable life & ! int5sity ( ! inorganic *emical reactions ?reefold4 ,accord+ to ! e/imate ( ! fam\s *emi/ ,liebig1 ! quantity ( organic matt] 7fre$ ( wat]7 :i* is produc$ by "o hect>e 7#b4e acres7 ( soil1 mead[l&1 or =e/ is ne>ly ! same1 approximately #b4e tons p] ye> 9 c5tral ,europe4 ,9 _m p>ts ( ! tropics ! gr[? is mu* m rapid2 9 o!r places1 9 ! des]ts & arctic regions1 mu* m feeble4 ,we may be ju/ifi$ 9 accept+ ,liebig's figure z an av]age = ! firm l& on our e>?4 ,( ! organic sub/ances to :i* we h ref]r$1 & :i* ma9ly consi/ ( cellulose1 c>bon makes up #dj p] c5t4 ,?us ! actual annual c>bon production by plants w\ld am\nt to #ac1jjj million tons--i4e41 n q fifte5 times m ?an ! consumption ( coal1 & ab\t "o-fiftie? ( ! quantity ( ! c>bon dioxide 9 ! air4 ,if1 !re=e1 all plants 7 to deposit _! c>bon 9 peat-bogs1 ! air w\ld soon be deplet$ ( its c>bon dioxide4 ,b x is only a fraction ( "o p] c5t4 ( ! coal :i* is produc$ by plants t is /or$ up = ! future 9 ?is way4 ,! re/ is s5t back into ! atmosph]e by combu/ion or by decay4 ,*amb]l9 relates t1 toge!r ) five o!r ,am]ican geologi/s1 he attempt$ to e/imate h[ long a "t w\ld be requir$ be=e ! c>bon dioxide ( ! air w\ld be consum$ by ! wea!r+ ( rocks4 ,_! v>i\s e/imates yield$ figures rang+ f #ejjj to #ah1jjj ye>s1 ) a probable av]age ( #aj1jjj ye>s4 ,! loss ( c>bonic acid by ! =mation ( peat may be e/imat$ at ! same figure4 ,! production ( c>bonic acid by ! combu/ion ( coal w\ld !re=e suffice to cov] ! loss ( c>bonic acid by wea!r+ & by peat =mation sev5 times ov]4 ,^? are ! two *ief factors decid+ ! consumption ( c>bonic acid1 & we ?us recognize t ! p]c5tage ( c>bonic acid 9 ! air mu/ be increas+ at a con/ant rate z long z ! consumption ( coal1 petroleum1 etc41 is ma9ta9$ at its pres5t figure1 & at a /ill m rapid rate if ?is consumption %\ld cont9ue to increase z x does n[4 ,?is consid]ation enables u to picture to ourselves ! possibility ( ! enorm\s plant-gr[? :i* mu/ h *>act]iz$ c]ta9 geological p]iods ( our e>?--= in/ance1 ! c>bonif]\s p]iod4 ,?is p]iod is kn[n to u f ! extraord9>ily l>ge numb] ( plants :i* we f9d emb$d$ 9 ! clay ( ! swamps ( ^? days4 ,^? plants 7 sl[ly c>boniz$ aft]w>ds1 & _! c>bon is 9 our age return$ to its orig9al place 9 ! h\sehold ( nature 9 ! %ape ( c>bonic acid4 ,a great portion ( ! c>bonic acid has disappe>$ f ! atmosph]e ( ! e>?1 & has be5 /or$ up z coal1 lignite1 peat1 petroleum1 or asphalt 9 ! s$im5t>y /rata4 ,oxyg5 0 lib]at$ at ! same "t1 & pass$ into our atmosph]ic sea4 ,x has be5 calculat$ t ! am\nt ( oxyg5 9 ! air--#abaf billion tons--approximately corresponds to ! mass ( fossil coal :i* is /or$ up 9 ! s$im5t>y /rata4 ,! supposition appe>s natural1 !re=e1 t all ! oxyg5 ( ! air may h be5 =m$ at ! exp5se ( ! c>bonic acid 9 ! air4 ,?is view 0 fir/ advanc$ by ,khne1 ( ,brussels1 9 #ahef1 & lat] discussions h /r5g!n$ its probability4 ,"p ( ! oxyg5 is c]ta9ly consum$ by wea!r+ processes1 & absorb$--e4g41 by sulphides & by f]ro-salts2 )\t ?is oxidation ! actual quantity ( oxyg5 9 ! air w\ld be great]4 ,on ! o!r h&1 !re are 9 ! s$im5t>y /rata _m oxidizable comp\nds--e4 g41 especially iron sulphides--:i* h probably be5 r$uc$ by ! int]action ( c>bon 7by organic comp\nds74 ,a l>ge numb] ( ! sub/ances :i* consume oxyg5 dur+ _! decomposition & decay h also be5 produc$ by ! int]m$iation ( ! coal :i* _h previ\sly be5 deposit$ "u lib]ation ( oxyg51 s t ^! sub/ances are1 by _! oxidation1 re/or$ to _! orig9al /ate4 ,we may h5ce take x z e/abli%$ t ! masses ( free oxyg5 9 ! air & ( free c>bon 9 ! s$im5t>y /rata approximately correspond to ea* o!r1 & t probably all ! oxyg5 ( ! atmosph]e owes its exi/5ce to plant life4 ,?is appe>s plausible also = ano!r reason4 ,we "k = c]ta9 t !re is "s free oxyg5 9 ! atmosph]e ( ! sun1 & t hydrog5 ab\nds 9 ! sun4 ,! e>?'s atmosph]e may orig9ally h be5 9 ! same condition4 ,:5 ! e>? cool$ gradually1 hydrog5 & oxyg5 comb9$ to wat]1 b an excess ( hydrog5 mu/ h rema9$4 ,! primeval atmosph]e ( ! e>? may also h conta9$ hydroc>bons1 z !y play an important "p 9 ! gases ( comets4 ,to ^! gases !re 7 add$ c>bonic acid & wat] vapor1 com+ f ! int]ior ( ! e>?4 ,?anks to its *emical in]tia1 ! nitrog5 ( ! air may n h und]gone mu* *ange 9 ! c\rse ( ! ages4 ,an ,engli% *emi/1 ,phipson1 claims to h %[n t bo? high] plants 7! corn-b9d7 & l[] organisms 7v>i\s bact]ia7 c live & develop 9 an atmosph]e devoid ( oxyg5 :5 x conta9s c>bonic acid & hydrog54 ,x is also possible t simple =ms ( vegetable life exi/$ be=e ! air conta9$ any oxyg51 & t ^! plants lib]at$ ! oxyg5 f ! c>bonic acid exhal$ by ! crat]s4 ,?is oxyg5 gradually 7possibly "u ! influ5ce ( electric dis*>ges7 conv]t$ ! hydrog5 & ! hydroc>bons ( ! air into wat] & c>bonic acid until ^? elem5ts 7 consum$4 ,! oxyg5 rema9$ 9 ! air1 ^: composition gradually approa*$ m ! actual /ate4#d ,footnote #d3 ,accord+ to ! op9ion ( a colleague ( m9e1 a botani/1 ! results ( ! exp]im5ts ( ,phipson mu/ be reg>d$ z v d\btful1 & "s oxyg5 w\ld appe> to be indisp5sable = ! gr[? ( plants4 ,we h to imag9e ! developm5t some:at z foll[s3 ,z ! e>? sep>at$ f ! sol> nebula1 its temp]ature 0 v high at fir/ 9 its out] portions4 ,at ?is temp]ature x 0 n able to reta9 ! light] gases1 l hydrog5 & helium1 = a long p]iod2 ! heavy gases1 l nitrog5 & oxyg51 rema9$4 ,! orig9al excess ( hydrog5 & helium disappe>$1 !re=e1 be=e ! cru/ ( ! e>? _h be5 =m$1 & ! atmosph]e ( ! e>? imm$iately aft] ! =mation ( ! cru/ conta9$ "s oxyg51 besides mu* nitrog51 c>bonic acid1 & wat] vapor4 ,! ma9 bulk ( ! actual atmosph]ic oxyg5 w\ld !re=e h be5 r$uc$ f c>bon dioxide by ! int]m$iation ( plants4 ,! view t cele/ial bodies may lose "p ( _! atmosph]e is due to ,john/one ,/oney4 ,! atmosph]ic gases escape ! m rapidly ! light] _! molecules & ! small] ! mass ( ! cele/ial bodies4 ,on ^! l9es we expla9 t ! small] cele/ial bodies l ! moon & ,m]cury1 h lo/ almo/ all _! atmosph]e1 :ile ! e>? has only lo/ hydrog5 & helium1 :i* aga9 h be5 reta9$ by ! sun4 ,?is oxyg5 is an ess5tial elem5t = ! production ( animal life4 ,z animal life /&s above vegetable life1 s animal life c\ld only orig9ate at a lat] /age ?an plant life4 ,plants require1 9 addition to suitable temp]ature1 only c>bonic acid & wat]1 & ^! gases w probably be f\nd 9 ! atmosph]es ( all ! planets z exhalations ( _! inn] inc&esc5t masses :i* are sl[ly cool+4 ,! pres5ce ( wat] vapor has directly be5 e/abli%$1 by means ( ! spectroscope1 9 ! atmosph]es ( o!r planets--,v5us1 ,jupit]1 & ,saturn--& indirectly by ! obs]vation ( a sn[-cap on ,m>s4 ,! spectroscope fur!r gives u indication ( ! pres5ce ( o!r gases4 ,!re is an int5se b& 9 ! r$ "p ( ! spectra ( ,jupit] & ,saturn1 ( wave-l5g? #j4jjjfah mm4 ,o!r new con/itu5ts ( unkn[n nature h be5 disc]n$ 9 ! spectra ( ,uranus & ,neptune4 ,on ! o!r h&1 !re is h>dly any1 or at any rate only a q insignificant1 atmosph]e on ! moon & on ,m]cury4 ,?is is easily und]/ood4 ,! temp]ature on t side ( ,m]cury :i* is turn$ away f ! sun is ne> absolute z]o4 ,all ! gases ( ! planet>y atmosph]e w\ld collect & cond5se !re4 ,if1 !n1 ,m]cury _h orig9ally an atmosph]e1 x mu/ h lo/ x z x lo/ its own rotation1 compell+ x to turn always ! same face t[>ds ! sun4 ,simil> reasons may acc\nt = ! abs5ce ( a lun> atmosph]e4 ,if ,v5us %\ld likewise always turn ! same side t[>ds ! sun1 z _m a/ronom]s ass]t1 ,v5us %\ld n h any notable atmosph]e1 nor cl\ds ei!r4 ,we "k1 h[ev]1 t ?is planet is surr\nd$ by a v m>k$ develop$ atmosph]e4#e ,footnote #e3 ,t results f ! v /rong refraction :i* light und]goes 9 ! atmosph]e ( ,v5us :5 ?is planet is se5 9 front ( ! sun's edge dur+ ! s-call$ ,v5us transits4 ,& t is ! /ronge/ objection to ! assumption t ,v5us foll[s ! example ( ,m]cury z reg>ds ! rotation ab\t its own axis4 ,s9ce1 n[1 w>m ages h alt]nat$ ) glacial p]iods1 ev5 aft] man appe>$ on ! e>?1 we h to ask ourselves3 ,is x probable t we %all 9 ! com+ geological ages be visit$ by a new ice p]iod t w drive u f our temp]ate c\ntries into ! hott] climates ( ,africa8 ,!re does n appe> to be mu* gr\nd = su* an appreh5sion4 ,! enorm\s combu/ion ( coal by our indu/rial e/abli%m5ts suffices to increase ! p]c5tage ( c>bon dioxide 9 ! air to a p]ceptible degree4 ,volcanism1 ^: deva/ations-- on ,krakatoa 7#ahhc7 & ,m>t9ique 7#aijb7--;h be5 t]rible 9 late ye>s1 appe>s to be gr[+ m int5se4 ,x is probable1 !re=e1 t ! p]c5tage ( c>bonic acid increases at a rapid rate4 ,ano!r circum/ance po9ts 9 ! same direction2 t is1 t ! sea seems to )draw c>bonic acid f ! air4 ,= ! c>bonic acid p]c5tage above ! sea & on isl&s is on an av]age #aj p] c5t4 less ?an ! above cont95ts4 ,illu/ration3 ,fig4 #ag4--,photograph ( ! surface ( ! moon1 9 ! vic9ity ( ! crat] ( ,cop]nicus4 ,tak5 at ! ,y]kes ,obs]vatory1 ,*icago1 ,u4 ,s4 ,a4 ,scale3 ,diamet] ( moon1 #j4ee m4 #ba4g 94 ,ow+ to ! abs5ce ( an atmosph]e & ( atmosph]ic precipitations1 ! precipit\s walls ( ! crat] & o!r elevations d n indicate any signs ( decay4 ,if ! c>bonic acid p]c5tage ( ! air _h kept con/ant = ages1 ! p]c5tage ( ! wat] w\ld h f\nd "t to get into equilibrium ) x2 b ! sea actually absorbs c>bonic acid f ! air4 ,?us ! sea-wat] mu/ h be5 9 equilibrium ) an atmosph]e :i* conta9$ less c>bonic acid ?an ! pres5t atmosph]e4 ,h5ce ! c>bonic acid p]c5tage has be5 increas+ ( late4 ,we (t5 he> lam5tations t ! coal /or$ up 9 ! e>? is wa/$ by ! pres5t g5]ation )\t any ?\ght ( ! future1 & we are t]rifi$ by ! awful de/ruction ( life & prop]ty :i* has foll[$ ! volcanic eruptions ( our days4 ,we may f9d a k9d ( consolation 9 ! consid]ation t "h1 z 9 e o!r case1 !re is good mix$ ) ! evil4 ,by ! influ5ce ( ! increas+ p]c5tage ( c>bonic acid 9 ! atmosph]e1 we may hope to enjoy ages ) m equable & bett] climates1 especially z reg>ds ! cold] regions ( ! e>?1 ages :5 ! e>? w br+ =? mu* m abundant crops ?an at pres5t1 = ! b5efit ( rapidly propagat+ mank9d4 ,,iii ,,radiation ,,& ,,con/itution ,,( ,,! ,,sun ,! "q has (t5 be5 discuss$ 9 pa/ ages1 & aga9 9 ! la/ c5tury1 9 h[ f> ! position ( our e>? )9 ! sol> sy/em may be reg>d$ z secure4 ,"o might appreh5d two ?+s4 ,ei!r ! di/ance ( ! e>? f ! sun might increase or decrease1 or ! rotation ( ! e>? ab\t its axis might be arre/$2 & ei!r ( ^! possibilities w\ld ?reat5 ! cont9uance ( life on ! e>?4 ,! problem ( ! /ability ( ! sol> sy/em has be5 inve/igat$ by ! a/ronom]s1 & _! patrons h (f]$ high prizes = a solution ( ! problem4 ,if ! sol> sy/em consi/$ m]ely ( ! sun & ! e>?1 ! e>?'s exi/5ce w\ld be secure = ages2 b ! o!r planets ex]cise a c]ta91 ?\gh small1 influ5ce ^u ! movem5ts ( ! e>?4 ,t ?is influ5ce c only be ( slight importance is due to ! fact t ! total mass ( all ! planets does n aggregate m ?an "o-sev5-hundr$-&-fiftie? ( ! mass ( ! sun1 &1 fur!r1 to ! fact t ! planets all move 9 ne>ly circul> orbits ar\nd ! c5tre1 ! sun1 s t !y nev] approa* "o ano!r closely4 ,! calculations ( ! a/ronom]s demon/rate t ! di/urbances ( ! e>?'s orbit are m]ely p]iodical1 repres5t+ long cycles ( f #ej1jjj to #b1jjj1jjj ye>s4 ,?us ! :ole effect is limit$ to a slight vacillation ( ! orbits ( ! planets ab\t _! mean positions4 ,s f> ev]y?+ is well & good4 ,b our sol> sy/em is trav]s$ by o!r cele/ial bodies1 mo/ly ( unkn[n1 b c]ta9ly n ( circul> orbits--namely1 ! comets4 ,! fe> ( a collision ) a comet /ill al>m$ ! ?9k]s ( ! pa/ c5tury4 ,exp]i5ce has1 h[ev]1 taught u t collisions betwe5 ! e>? & comets d n lead to any s]i\s consequ5ce4 ,! e>? has sev]al times pass$ ?r\gh ! tails ( comets--= in/ance1 9 #ahai & #ahfa--;& x 0 only ! calculat+ a/ronom] :o became aw>e ( ! fact4 ,once on su* an occasion we h ?\ght t we obs]v$ a gl[ l t ( an aurora 9 ! sky4 ,:5 ! e>? 0 draw+ ne> ! d5s] p>ts ( ! comet1 p>ticles fell on ! e>? 9 ! %ape ( %[]s ( %oot+-/>s1 )\t do+ any appreciable damage4 ,! mass ( comets is too small p]ceptibly to di/urb ! pa?s ( ! planets4 ,! rotation ( ! e>? ab\t its axis %\ld sl[ly be dim9i%$ by ! effects ( ! tides1 s9ce !y act l a brake appli$ to ! surface ( ! e>?4 ,?is ret>dation is1 h[ev]1 s unimportant t ! a/ronom]s h n be5 able to e/abli% x 9 hi/orical times4 ,! sl[ %r9kage ( ! e>? some:at c\nt]acts ?is effect4 ,laplace believ$ t we 7 able to d$uce1 f an analysis ( ! obs]vations ( sol> eclipses 9 anci5t c5turies1 t ! l5g? ( ! day _h n alt]$ by m ?an #j4ja second s9ce ! ye> #gbi ,b4,c4 ,we "k t ! sun1 unaccompani$ by its planets1 is mov+ 9 space t[>ds ! con/ellation ( ,h]cules ) a velocity ( #bj km4 7#ac miles7 p] second1 :i* is amaz+ to our t]re/rial conceptions4 ,possibly ! con/itu5ts ( our sol> sy/em might collide ) "s o!r unkn[n cele/ial body on ?is j\rney4 ,b z ! cele/ial bodies are sp>sely di/ribut$1 we may hope t _m billions ( ye>s w elapse be=e su* a cata/rophe w take place4 ,9 me*anical respects ! /ability ( our sy/em appe>$ to be well e/abli%$4 ,s9ce ! mod]n !ory ( heat has made its triumphant entry into natural sci5ce1 h[ev]1 ! aspect ( matt]s has *ang$4 ,we are conv9c$ t all life & all motion on ! e>? c be trac$ back to sol> radiation4 ,! tidal motions alone make a r unimportant exception4 ,we h to ask ourselves3 ,w n ! /ore ( en]gy 9 ! sun1 :i* goes out1 n only to ! planets1 b to a f> great] ext5t into unkn[n doma9s ( cold space1 come to an end1 & w n t be ! end ( all ! joys & sorr[s ( e>?ly exi/5ce8 ,! position appe>s desp]ate :5 we consid] t only "o "p 9 #bcjj millions ( ! sol> radiation b5efits ! e>?1 & p]haps t5 times z mu* ! :ole sy/em1 ) all its moons4 ,! sol> radiation is s p[]ful t e gramme ( ! mass ( ! sun loses two calories 9 ! c\rse ( a ye>4 ,if1 !re=e1 ! specific heat ( ! sun 7 ! same z t ( wat]1 :i* 9 ?is respect surpasses mo/ o!r sub/ances1 ! sol> temp]ature w\ld fall by #b ,c5t4 7#c4f ,f47 e ye>4 ,z1 n[1 ! temp]ature ( ! sun 9 its out] portion has be5 e/imat$ at f #fjjj to #gjjj1 ! sun %\ld h cool$ completely )9 hi/orical times4 ,& ?\gh ! int]ior ( ! sun mo/ probably has a va/ly high] temp]ature ?an ! out] portions :i* we c obs]ve1 we %\ld1 all ! same1 h to expect t ! sol> temp]ature & radiation w\ld noticeably h dim9i%$ 9 hi/orical times4 ,b all ! docum5ts f anci5t ,babylon & ,egypt seem to po9t out t ! climate at ! dawn ( hi/orical times 0 9 ^? c\ntries ne>ly ! same z at pres5t1 & t1 !re=e1 ! sun %one ov] ! mo/ anci5t repres5tatives ( culture 9 ! same way z x %9es on _! desc5dants n[4 ,! !sis has frequ5tly be5 advanc$1 !re=e1 t ! sun has 9 its heat balance n only an exp5diture side1 b also an almo/ equally sub/antial income side4 ,! ,g]man physician ,r4 ,may]1 :o has ! immortal m]it ( fir/ hav+ giv5 expression to ! conception ( a relation betwe5 heat & me*anical "w1 direct$ 8 att5tion also to ! h\sehold ( ! sun4 ,he sugge/$ t sw>ms ( meteorites1 ru%+ into ! sun ) an amaz+ velocity 7( ov] #fjj km4 p] second71 w\ld1 :5 /opp$ 9 _! motion1 g5]ate heat at ! rate ( #de million calories p] gramme ( meteorites4 ,9 future ages x w\ld be ! turn ( ! planets to su/a9 = "s "t long] ! sp>k ( life 9 ! sun1 by ! sacrifice ( _! own exi/5ces4 ,! sun w\ld !re=e1 l ! god ,saturn1 h to dev\r its own *ildr5 9 ord] to cont9ue its exi/5ce4 ,( h[ little avail t w\ld be we le>n f ! consid]ation t ! fall ( ! e>? into ! sun w\ld n be able to prolong ! heat exp5diture ( ! sun by z _m z a hundr$ ye>s4 ,by _! ru% into ! sun1 almo/ uni=mly f all sides1 ! meteorites w\ld1 moreov]1 long s9ce h put a /op to ! rotation ( ! sun ab\t its axis4 ,fur!r1 by virtue ( ! increas+ mass & ! h5ce augm5t+ attraction ( ! sun1 ! l5g? ( our ye> w\ld h _h to dim9i% by ab\t #b4h seconds p] ye>1 :i* is 9 absolute contradiction to ! obs]vations ( ! a/ronom]s4 ,accord+ to ,may]'s !sis1 a correspond+ numb] ( meteorites w\ld1 f9ally1 also h to tumble ^u ! surface ( ! e>?1 & 7accord+ to data :i* w be furni%$ 9 ,*apt] ,,iv47 !y %\ld raise ! surface temp]ature to ab\t #hjj4 ,! !sis is !re=e mislead+4 ,we mu/ look = ano!r explanation4 ,x occurr$ to ,helmholtz1 "o ( ! mo/ em95t inve/igators 9 ! doma9 ( ! me*anical !ory ( heat1 t1 in/ead ( ! meteorites1 p>ts ( ! sun itself might fall t[>ds its c5tre1 or1 9 o!r words1 t ! sun 0 %r9k+4 ,ow+ to ! high gravitation ( ! sun 7#bg4d times great] ?an on ! surface ( ! e>?71 ! %r9kage w\ld lib]ate a great am\nt ( heat4 ,helmholtz calculat$ t1 9 ord] to cov] ! heat exp5diture ( ! sun1 a %r9kage ( its diamet] by #fj m4 annually w\ld be requir$4 ,if ! sun's diamet] %\ld only be dim9i%$ by "o-hundr$? ( "o p] c5t4--a *ange :i* we %\ld n be able to e/abli%--! heat loss w\ld be cov]$ = m ?an #bjjj ye>s4 ,t seems at fir/ satisfactory4 ,b if we proce$ ) our e/imate1 we f9d t if ! sun w5t on los+ z mu* heat z at pres5t = sev5te5 million ye>s x w\ld h to contract )9 ?is p]iod to a qu>t] ( its pres5t volume1 & w\ld !re=e acquire a d5sity l t ( ! e>?4 ,long be=e t1 h[ev]1 ! radiation f ! sun w\ld h be5 decreas$ s p[]fully t ! temp]ature on ! e>?'s surface w\ld no long] rise above freez+-po9t4 ,helmholtz1 on ?is argum5t1 limit$ ! fur!r exi/5ce ( ! e>? to ab\t six million ye>s4 ,t is less satisfactory4 ,b we "k no?+ ( ! future & mu/ be cont5t ) possibilities4 ,n s1 h[ev]1 if we calculate back ) ! aid ( ,helmholtz's !ory4 ,accord+ to ?is !ory1 & accord+ to ,helmholtz's own data1 a /ate l ! pres5t _c h exi/$ = m ?an t5 million ye>s4 ,s9ce1 n[1 geologi/s h come to ! conclusion t ! petrefactions :i* we f9d 9 ! fossil-be>+ /rata ( ! e>? h ne$$ at lea/ a hundr$ million ye>s = _! =mation1 & m probably a ?\s& million ye>s1 & s9ce1 moreov]1 ! /ill m anci5t =mations--! s-call$ precambrian /rata--h be5 deposit$ 9 equally long or /ill long] p]iods1 we see t ! !ory ( ,helmholtz is unsatisfactory4 ,a some:at peculi> way out ( ! dilemma has be5 sugge/$ by a few sci5ti/s4 ,we "k t "o gramme ( ! wond]ful elem5t radium emits ab\t #abj calories p] h\r1 or 9 ! c\rse ( a ye>1 9 r\nd numb]s1 a million calories4 ,?is radiation seems to cont9ue unimpair$ = ye>s4 ,if we n[ assume t ea* kilogramme ( ! mass ( ! sun conta9s only two milligrammes ( radium1 t am\nt w\ld be suffici5t to balance ! heat exp5diture ( ! sun = all future ages4 ,)\t "s fur!r auxili>y hypo!sis1 we c1 h[ev]1 n li/5 to ?is sugge/ion4 ,x presupposes t heat is creat$ out ( no?+4 ,"s sci5ti/s1 inde$1 believe t radium may absorb a radiation1 com+ f space1 9 "s unkn[n mann] & conv]t x into heat4 ,be=e we ent] s]i\sly into a discussion ( ?is explanation we %all h to answ] ! que/ions :]e t radiation comes f & :]e x takes its /ore ( en]gy4 ,we mu/1 !re=e1 aga9 se>* = ano!r s\rce ( heat en]gy = ! sun4 ,be=e we c hope to f9d x1 we _h bett] /udy ! sun itself a little4 ,all sci5ti/s are agre$ t ! sun is ( ! same con/itution z ! ?\s&s ( lum9\s />s :i* we see 9 ! sky4 ,accord+ to ! color ( ! light :i* !y emit1 />s are classifi$ z :ite1 yell[1 & r$ />s4 ,! diff]5ces 9 _! light become mu* m di/9ct :5 we exam9e !m spectroscopically4 ,9 ! :ite />s ! helium & hydrog5 l9es pr$om9ate decid$ly2 ! helium />s conta91 9 addition1 oxyg54 ,metals are comp>atively little repres5t$2 b !y play a ma9 "p 9 ! spectra ( ! yell[ />s1 9 :i*1 fur!r1 "s b&s become visible4 ,9 ! spectra ( ! r$ />s we notice _m b&s :i* indicate t *emical comp\nds are pres5t 9 ! out] portions4 ,ev]ybody kn[s t ! plat9um wire or ! filam5t ( an inc&esc5t lamp :i* has be5 heat$ to inc&esc5ce by ! electric curr5t fir/ %9es r$di%1 !n yell[ :5 ! curr5t is increas$1 & f9ally m & m :ite4 ,at ! same "t ! temp]ature rises4 ,we c e/imate ! temp]ature f ! brightness ( ! gl[4 ,if we "k ! wave-l5g? ( ! radiations ( t color :i* emits ! greate/ am\nt ( heat 9 ! spectrum 7x %\ld be a normal spectrum71 x is easy to calculate ! temp]ature ( ! /> f ,wi5's law ( displacem5ts4 ,we ne$ only divide #b4hi by ! respective wave-l5g? express$ 9 mm4 to f9d ! absolute temp]ature ( ! />2 by d$uct+ #bgc f ! result1 we obta9 ! temp]ature 9 degrees ,c5t4 on ! ord9>y scale4 ,= ! sun ! maximum ( heat radiation lies ne> wave-l5g? #j4jjjee 79 ! gre5i%-yell[ light71 & !re=e ! absolute temp]ature ( ! radiat+ disk ( ! sun1 ! s-call$ photosph]e1 %\ld be #ebee absolute1 or ne>ly #ejjj ,c5t4 ,b our atmosph]e weak5s ! sunlight1 & x also causes a displacem5t ( ! maximum radiation 9 ! spectrum4 ,! same applies to ! sun's own atmosph]e1 s t we h to adopt a high] e/imate ?an #ejjj ,c5t4 ,by means ( ,/efan's law ( radiation1 ! sol> temp]ature has be5 e/imat$ at ab\t #fbjj1 :i* w\ld correspond to a wave-l5g? ( ab\t #j4jjjde mm4 ,?is correction is !re=e significant4 ,ab\t half ( x has to be ascrib$ to ! influ5ce ( ! sol> atmosph]e1 ! o!r half to ! t]re/rial atmosph]e4 ,a ,hung>ian a/ronom]1 ,h>knyi1 has det]m9$ 9 ! same way ! temp]ature ( sev]al :ite />s 7,vega & ,sirius71 & f\nd x to be ab\t #ajjj high] ?an t ( ! sun1 :ile ! r$ /> ,betelgeuse1 ! mo/ prom95t /> 9 ,orion1 w\ld h a temp]ature by #bejj l[] ?an t ( ! sun4 ,x mu/ expressly be /at$ t 9 mak+ ^! e/imates we und]/& by ! temp]ature ( ! /> 9 ?is case ! temp]ature ( a radiat+ body :i* emits ! same light z t :i* rea*es u f ! />4 ,b ! /ell> light und]goes important *anges on its way to u4 ,we le>n f obs]v+ new />s t a /> may be surr\nd$ by a cl\d ( cosmical du/ :i* sifts ! blue rays out & p]mits ! r$ ones to pass4 ,! /> !n %9es ) a less brilliantly :ite light ?an 9 ! abs5ce ( ! cl\d4 ,! consequ5ce is t we e/imate ! temp]ature l[] ?an x really is4 ,9 ! r$ />s b&s h be5 notic$1 indicat+1 z we h already said1 ! pres5ce ( *emical comp\nds4 ,! mo/ int]e/+ ( ^! are ! comp\nds ( cyanog5 & ( c>bon1 probably ) hydrog51 :i* appe> to resemble ^? obs]v$ by ,swan 9 ! spectrum ( gas flames & :i* 7 nam$ aft] him4 ,x 0 =m]ly ?\ght t ! pres5ce ( ^! comp\nds impli$ l[] temp]ature4 ,b we %all see t ?is conclusion is n firmly e/abli%$4 ,hale has f\nd dur+ eclipses ( ! sun t exactly ! same comp\nds occur imm$iately above ! lum9\s cl\ds ( ! sun4 ,!y are probably m num]\s bel[ ! cl\ds1 :]e ! temp]ature is no d\bt high]1 ?an above !m4 ,h[ev] t may be1 we h reason to assume t ! n[ yell[ sun 0 once a :ite /> l ! brilliant ,sirius1 t x has sl[ly cool$ d[n to its pres5t appe>ance1 & t x w "s day %9e ) ! r$di% light ( ,betelgeuse4 ,! sun w !n only radiate a sev5? ( ! heat :i* x emits n[1 & x is v likely t ! e>? w h be5 trans=m$ into a glacial des]t long be=e t "t4 ,x has already be5 po9t$ out t ! atmosph]es ( bo? ! sun & ( ! e>? produce a /rong absorption ( ! sol> rays1 & especially ( ! blue & :ite rays4 ,x is = ?is reason t ! light ( ! sun appe>s m r$ 9 ! ev5+ ?an at noon1 because 9 ! =m] case x has to pass ?r\gh a ?ick] lay] ( air1 :i* absorbs ! blue rays4 ,= ! same reason ! limb ( ! sun appe>s m r$ 9 spectroscopic exam9ations ?an ! c5tre ( ! sun4 ,?is weak5+ ( ! sun's light is due to ! f9e du/ p]vad+ ! atmosph]es ( ! e>? & ! sun4 ,:5 ! products ( /rong volcanic eruptions1 l ! eruptions ( ,krakatoa 9 #ahhc & ( ,mont ,pele 9 #aijb1 fill$ ! atmosph]e ) a f9e volcanic du/1 ! sun appe>$ di/9ctly r$ :5 /&+ l[ 9 ! horizon4 ,x 0 ?is du/ t caus$ ! r$ gl[4 ,:5 we exam9e an image ( ! sun :i* has be5 ?r[n on a scre5 by ! aid ( a l5s or a sy/em ( l5ses1 we notice on ! sun's disk a mottl+ ( *>act]i/ic d>k] spots4 ,^! spots /ruck ! att5tion ( ,galileo1 & !y 7 discov]$ almo/ simultane\sly by him1 by ,fabricius1 & by ,s*e9] 7#afaj-afaa74 ,^! spots h s9ce be5 ! mo/ dilig5tly /udi$ features ( ! sun4 ,we c>efully det]m9e _! numb] & sizes1 & comb9e ^! two data to make ! s-call$ sun-spot numb]s4 ,^! numb]s *ange f ye> to ye> 9 a r irregul> way1 ! p]iod am\nt+ on an av]age to #aa4a ye>s4 ,! spots appe> 9 two belts on ! sun1 & !y glide ov] ! disk 9 ! c\rse ( ?irte5 or f\rte5 days4 ,sometimes !y reappe> aft] ano!r ?irte5 or f\rte5 days4 ,x is !re=e believ$ t !y lie comp>atively quiet on ! surface ( ! sun1 & t ! sun rotates ab\t its own axis 9 ab\t tw5ty-sev5 days1 s t aft] t p]iod ! same po9ts are aga9 opposite ! e>?4 ,?is is ! s-call$ synodical p]iod4 ,! great int]e/ :i* atta*es to ! /udy ( ^! features lies 9 ! fact t simultane\sly ) ^! spots sev]al o!r ph5om5a seem to v>y :i* atta9 _! maxima at ! same "t4 ,su* are1 9 ! fir/ in/ance1 ! pol> lights & ! magnetic v>iations1 &1 to a less] degree1 ! cirrus cl\ds & temp]ature *anges1 z well z sev]al o!r meteorological ph5om5a 7comp>e ,*apt] ,v474 ,ab\t ! sun-spots we notice ! s-call$ facul--portions :i* are mu* bright] ?an _! surr\nd+s4 ,:5 we c>efully exam9e a /rongly magnifi$ image ( ! sun1 we f9d t x has a granulat$ appe>ance 7,fig4 #ah74 ,langley comp>es ! disk to a grayi%-:ite clo? almo/ hidd5 by flakes ( sn[4 ,! less bright portions are designat$ 8pores10 ! bright] portions 8granules40 ,x is g5]ally assum$ t ! granules correspond to cl\ds :i* rise l ! cl\ds ( our atmosph]e on ! top ( asc5d+ convection curr5ts4 ,b :ile ! t]re/rial cl\ds are =m$ ( drops ( ra9 or ( cry/als ( ice1 ! granules consi/ probably ( soot--t is to say1 cond5s$ c>bon--& ( drops ( metals1 iron1 & o!rs4 ,! smalle/ granule :i* we are able to disc]n has a diamet] ( ab\t #bjj km4 7#acj miles74 ,illu/ration3 ,fig4 #ah4--,sun-spot gr\p & granulation ( ! sun4 7,photograph$ at ! ,meudon ,obs]vatory1 ne> ,p>is1 ,april #a1 #ahhd7 ,! facul are =m$ by v l>ge accumulations ( cl\ds :i* are c>ri$ up by /rong asc5d+ curr5ts & spread ov] l>ge areas1 z 9 our cyclones4 ,! spots correspond to desc5d+ masses ( gas ) ris+ temp]atures1 :i* are !re=e 8dry0 & d n c>ry any cl\ds1 z 9 t]re/rial anticyclones4 ,?r\gh ^! holes 9 ! walls ( sol> cl\ds we peep a little f>!r into ! gigantic masses ( gas1 & we obta9 an idea ( ! /ate ( affairs 9 ! deep] /rata ( ! sun4 ,! dep? ( ! wall ( cl\d is1 ( c\rse1 n l>ge comp>$ to ! radius ( ! sun4 ,illu/ration3 ,fig4 #ai4--,"p ( ! sol> spectrum ( ,janu>y #c1 #ahgb4 ,aft] ,langley4 ,! bright horizontal b&s are due to prom95ces4 ,9 ! middle 7at #bjh7 ! hydrog5 l9e ,f1 /rongly di/ort$ by viol5t agitation ,! /udy ( ! spectra af=ds u ! be/ insight into ! nature ( ! diff]5t p>ts ( ! sun4 ,! spectra tea* u n only ! con/itu5ts ( ^! p>ts1 b also ! velocities ) :i* !y move4 ,we h le>n$ 9 ?is way t1 ly+ above ! lum9\s cl\ds ( ! sun :i* are radiat+ to u1 !re are great masses ( gas conta9+ mo/ ( our t]re/rial elem5ts4 ,we di/+ui% p>ticul>ly 9 !m iron1 magnesium1 calcium1 sodium1 helium1 & hydrog54 ,! two la/-m5tion$ con/itu5ts1 be+ ! lea/ d5se1 are f\nd p>ticul>ly 9 ! out]mo/ /rata ( ! atmosph]e4 ,! sol> atmosph]e becomes visible :51 dur+ an eclipse ( ! sun1 ! disk ( ! moon has proce$$ s f> z to cov] ! int5sely lum9\s cl\ds 9 ! s-call$ photosph]e4 ,ow+ to its /rong p]c5tage ( hydrog51 ! gase\s atmosph]e g5]ally %9es 9 ! purple hue :i* is *>act]i/ic ( ?is elem5t4 ,?is /ratum ( gas is also call$ ! *romosph]e 7f ! ,greek ^w 1 mean+ color74 ,its ?ickness is e/imat$ at f #gjjj to #ijjj km4 7#ejjj to #fjjj miles74 ,f x rise rays ( fire ov] ! surr\nd+ surface l blades ( grass on mead[s1 to :i* _! appe>ance has be5 lik5$4 ,illu/ration3 ,fig4 #bj4--,metallic prom95ces 9 vortex motion4 ,! :ite spot m>ks ! size ( ! e>? ,illu/ration3 ,fig4 #ba4--;,f\nta9-l metallic prom95ces ,:5 ^! flames rise /ill high]1 to ab\t #ae1jjj km4 7#icjj miles7 or m1 !y are call$ protub]ances or prom95ces4 ,_! numb] z well z _! altitude gr[ ) ! numb] ( sun-spots4 ,!y are di/+ui%$ z metallic & z quiet prom95ces4 ,! =m] are *>act]iz$ by p>ticul>ly viol5t motion1 z w become app>5t f ,figs4 #bj & #ba1 & !y conta9 l>ge am\nts ( metallic vapor4 ,!y appe> only )9 ! belt ( sun-spots :i* are mo/ pron\nc$ at a di/ance ( ab\t #bj f ! sol> equator4 ,_! movem5ts are s viol5t t !y (t5 trav]se sev]al hundr$s ( kilometres 9 a second4 ,! ,hung>ian ,fnyi obs]v$1 inde$1 on ,july #ae1 #ahie1 a prom95ce ^: greate/ velocity 9 ! l9e ( sight1 measur$ spectroscopically1 am\nt$ to #hfb km4 7#ecf miles71 & ^: maximum velocity at "r angles to ?is direction 0 #hdj km4 p] second4 ,^! colossal velocities di/+ui% ! highe/ p>ts1 :ile ! l[] portions1 :i* are ! mo/ d5se & :i* conta9 mo/ metallic vapor1 are less mobile1 z might be expect$4 ,_! altitude above ! sun's surface may rea* exce$+ly high figures1 & ?is applies also to ! quiet prom95ces4 ,! above-m5tion$ prom95ce ( ,july #ae1 #ahie1 rea*$ a height ( #ejj1jjj km41 & ,langley obs]v$1 on ,octob] #g1 #ahhj1 "o at an altitude ( #efj1jjj km41 ^: tip1 !re=e1 ne>ly atta9$ an elevation equal to t ( a radius ( ! sun1 #fij1jjj km4 above ! limb ( ! sun's photosph]e4 ,! mean altitude ( ^! prom95ces is #dj1jjj km4 ,aft] _! discov]y by ,lector ,vass5ius1 ( ,g!borg1 9 #agcc1 !y c\ld only be /udi$ dur+ total sol> eclipses1 until ,locky] & ,janss5 taught u1 9 ! ye> #ahfh1 h[ to obs]ve !m 9 full sunlight by means ( ! spectroscope4 ,illu/ration3 ,fig4 #bb4--,quiet prom95ces ( smoke-column type ,illu/ration3 ,fig4 #bc4--,quiet prom95ces1 %ape ( a tree4 ,! :ite spot indicates ! size ( ! e>? ,illu/ration3 ,fig4 #bd4--;,diagram illu/rat+ ! diff]5ces 9 ! spectra ( sun-spots & ( ! photosph]e4 ,"s l9es 9 ! spot spectrum are /rong]1 o!rs fa9t]1 ?an 9 ! photosph]e spectrum4 ,9 ! c5tral portion1 two rev]sals2 to ! "r1 two b&s4 ,aft] ,mit*ell ,illu/ration3 ,fig4 #be4--,spectrum ( a sun-spot1 ! c5tral b& betwe5 ! two portions ( ! photosph]e spectrum4 ,! spot spectrum is bord]$ ) ! half-%ad[s ( ! edge ( ! spot4 ,aft] ,mit*ell ,! quiet prom95ces consi/ almo/ exclusively ( hydrog5 & helium2 sometimes !y conta9 also traces ( metallic gases4 ,!y resemble cl\ds float+ quietly 9 ! sol> atmosph]e1 or masses ( smoke com+ f a *imney4 ,!y may appe> any:]e on ! sun1 & _! /ability is s great t !y h sometimes be5 wat*$ dur+ a complete sol> rotation 7= ab\t =ty days72 ?is is possible only :5 !y occur 9 ! neighborhood ( ! poles1 :]e !y always rema9 visible outside ! sun's limb4 ,figs4 #bb & #bc %[ sev]al su* prom95ces accord+ to ,"y4 ,illu/ration3 ,fig4 #bf4--,! great sun-spot ( ,octob] #i1 #aijc4 ,tak5 ) ! photo-heliograph ( ,gre5wi* 9 ! usual mann]4 ,! spot is %[n at mean level ( ! calcium facul4 ,! two foll[+ photographs %[ a l[]-level & a high]-level section ?r\gh ! calcium facul ,sometimes ! matt] ( ! prom95ces seems to fall back ^u ! surface ( ! sun betwe5 ! small] flames ( fire :i* we h lik5$ to blades ( grass 7,fig4 #ba74 ,9 mo/ cases1 h[ev]1 ! prom95ces appe> sl[ly to dissolve4 ,:5 _! brilliant gl[ fades ow+ to _! int5se radiation1 !y c no long] be obs]v$4 ,! quiet prom95ces1 :i* seem to float at heights ( ab\t #ej1jjj km4 & at /ill great] heights1 mu/ !re be almo/ 9 a vacuum4 ,_! p>ticles _c be support$ by any surr\nd+ gases1 aft] ! mann] ( ! drops ( wat] 9 t]re/rial cl\ds4 ,9 ord] t !y may rema9 float+ !y mu/ be pu%$ away f ! sun by a peculi> =ce--! radiation pressure 7see ,*apt] ,,iv474 ,illu/ration3 ,fig4 #bg4--,! great sun-spot ( ,octob] #i1 #aijc4 ,photograph ( ! l[-level calcium facul ) ! aid ( ! light ( ! calcium l9e ,h4 ,! spot is n obscur$ by ! facul--at lea/1 n s mu* z 9 ! foll[+ illu/rations ,! facul c be /udi$ 9 ! same way z ! prom95ces1 & ( late ,desl&res & ,hale h us$ = ?is purpose a special in/rum5t1 ! heliograph 7comp>e ,figs4 #bf to #bi74 ,:5 ! facul approa* ! limb ( ! sun !y appe> p>ticul>ly brilliant by comp>ison ) _! surr\nd+s4 ,t seems to indicate t !y are ly+ at a great altitude1 & t _! light is h5ce n weak5$ by ! sup]pos$ hazy /ratum4 ,:5 !y rea* ! sun's limb !y appe> to u l rais$ portions ( ! photosph]e4 ,! cl\ds :i* =m ^! facul are c>ri$ upw>d by p[]ful asc5d+ /reams ( gas ^: expansion is due to ! dim9ution ( ! gase\s pressure4 ,illu/ration3 ,fig4 #bh4--,! great sun-spot ( ,octob] #i1 #aijc4 ,photograph ( ! high]-level calcium facul1 tak5 ) ! light ( ! c5tral portion ( ! l9e ,h 7calcium74 ,! high]-level facul hide ! spot1 indicat+ t ! facul spread consid]ably dur+ _! asc5t ,illu/ration3 ,fig4 #bi4--,! great sun-spot ( ,octob] #i1 #aijc4 ,photograph ( ! hydrog5 facul1 tak5 ) ! light ( ! spectral l9e ,f 7hydrog574 ,only ! d>ke/ portions ( ! spot are visible4 ,! o!r portions are obscur$ by masses ( ! hydrog51 :i* 7 evid5tly 9 a re/less /ate ,sun-spots display _m peculi>ities 9 _! spectra 7,figs4 #bd & #be74 ,v prom95t is always ! helium l9e2 prom95t likewise ! d>k sodium l9es1 :i* are m>k$ly wid5$ & :i* %[ 9 _! middle portions a bright l9e--! s-call$ rev]sal ( l9es 7,fig4 #bd74 ,?is occurr5ce indicates t ! metal is ly+ 9 a deep] /ratum4 ,9 ! r$ portion ( ! spectrum we f9d b&s1 j z 9 ! spectra ( ! r$ />s4 ,^! b&s1 :i* appe> to be resolv$ into cr[ds ( l9es by ! aid ( p[]ful in/rum5ts1 indicate ! pres5ce ( *emical comp\nds4 ,s9ce ! spot is comp>atively ( feeble int5sity1 its spectrum appe>s sup]pos$ l a less bright ribbon ^u ! backgr\nd ( ! spectrum ( ! m lum9\s photosph]e4 ,! violet end ( ! sun-spot spectrum is p>ticul>ly weak5$4 ,al?\gh ! spot has ! appe>ance ( a pit 9 ! photosph]e1 & :5 on ! sun's limb makes x look z if a piece _h be5 cut out ( ! edge1 x yet does n appe> d>k] ?an ! sun's edge4 ,t po9ts to ! conclusion t ! light emitt$ by ! spot emanates *iefly f its upp]1 cold portions4 ,illu/ration3 ,fig4 #cj4--,photograph ( ! sol> corona ( #aijj4 7,aft] ,langley & ,abbot47 ,illu/rat+ ! appe>ance ( ! corona 9 ye>s ( m9imum sun-spot frequ5cy ,! light com+ f ! deep] portions is di/9ctly absorb$ to a l>ge degree by ! high]-ly+ /rata4 ,! sun-spots also appe> to become n>r[] 9 _! l[] p>ts1 ow+ to ! compression ( ! gases at great] dep?s1 & "o may reg>d _! funnel-%ap$ cl\d-walls z 8half-%ad[s10 :i* appe> d>k] ?an ! surr\nd+s1 b bright] ?an ! s-call$ core ( ! spot4 ,! weak5+ ( ! violet end ( ! spectrum is probably due to ! pres5ce ( f9e p>ticles ( du/ 9 ! sol> gases1 j z !y cause ! correspond+ weak5+ ( ! violet end ( ! spectrum ( ! sun's limb4 ,! b&s 9 ! r$ p>ts ( ! sun-spot spectrum may orig9ate f ! deep] portions ( ! spot1 because all ! high] p>ts ( ! sol> atmosph]e yield simple1 %>p l9es4 ,! b&s sugge/ t *emical comp\nds c exi/ at ! high] pressure ( ! inn] portions ( ! sun1 & t ^! comp\nds are decompos$ 9 ! out] p>ts ( ! sun1 to give ! l9e spectra ( *emical elem5ts4 ,illu/ration3 ,fig4 #ca4--,photograph ( ! sol> corona ( #ahgj4 7,aft] ,davis47 ,! ye> #ahgj 0 "o ( maximum sun-spot frequ5cy ,! enigmatical corona lies f>!r out 9 ! atmosph]e ( ! sun4 ,x consi/s ( /ream]s :i* may ext5d beyond ! disk ( ! sun to ! l5g? ( sev]al sol> diamet]s4 ,! corona c only be obs]v$ at total eclipses ( ! sun4 ,figs4 #cj to #cb illu/rate ! appe>ance ( ?is v peculi> ph5om5on4 ,illu/ration3 ,fig4 #cb4--,photograph ( ! sol> corona ( #ahih4 7,aft] ,maund]47 #ahih 0 a ye> ( av]age sol> activity ,:5 ! numb] ( sun-spots is small1 ! corona /ream]s ext5d l huge brooms f ! equatorial p>ts1 & ! feebl] rays ( ! corona ne> ! sol> poles are !n b5t d[nw>d to ! equator1 j l ! l9es ( =ce ab\t ! poles ( a magnet 7,fig4 #cj74 ,we suppose1 = ?is reason1 t ! sun acts l a /rong magnet1 ^: poles are situat$ ne> ! geographical poles ( ! sun4 ,9 ye>s :i* are ri*] 9 sun-spots ! di/ribution ( ! /ream]s ( ! corona is m uni=m4 ,at mod]ate sun-spot frequ5cy1 l>ge numb]s ( rays seem to emanate f ! neighborhood ( ! maximum belt ( sun-spots1 s t ! corona (t5 assumes a quadrangul> %ape 7comp>e ,fig4 #cb74 ,^! rem>ks hold = ! 8out] corona10 :ile ! inn] portion1 ! s-call$ 8inn] corona10 %9es 9 a m uni=m light4 ,! spectroscopic exam9ation demon/rates t ! light consi/s ma9ly ( hydrog5 gas & ( an unkn[n gas designat$ coronium1 :i* p>ticul>ly seems to occur 9 ! high] p>ts ( ! inn] corona4 ,! out] /ream]s ( ! corona1 on ! contr>y1 yield a cont9u\s spectrum :i* %[s t ! light is radiat$ by solid or liquid p>ticles4 ,9 ! spectrum ( ! coronal rays at an extreme di/ance f ! disk1 a/ronom]s h sometimes fanci$ t !y disc]n$ d>k l9es on a bright gr\nd1 j z 9 ! spectrum ( ! photosph]e4 ,x has be5 assum$ t ?is light is reflect$ sunlight1 orig9at+ f small solid or liquid p>ticles ( ! out] corona4 ,x mu/ be reflect$1 because x is p>tly pol>iz$4 ,! radiat+ disposition ( ! out] corona indicates ! action ( a =ce1 ! radiation pressure1 :i* drives ! small] p>ticles away f ! c5tre ( ! sun4 ,z reg>ds ! temp]ature ( ! sun1 we h already se5 t ! two me?ods appli$ = its det]m9ation h yield$ some:at unequal results4 ,f ! int5sity ( ! radiation1 ,*ri/ians51 & aft]w>ds ,w>burg1 calculat$ a temp]ature ( ab\t #fjjj ,c5t4 ,wilson & ,gray f\nd = ! c5tre ( ! sun #fbjj1 :i* !y aft]w>ds correct$ into #hjjj4 ,ow+ to ! absorption ( light by ! t]re/rial & ! sol> atmosph]es1 we always f9d too l[ values4 ,t applies1 to a /ill great] ext5t1 to any e/imate bas$ ^u ! det]m9ation ( t wave-l5g? = :i* ! heat emission f ! sol> spectrum is maximum4 ,le ,*ateli] comp>$ ! int5sity ( sunlight filt]$ ?r\gh r$ glass ) ! int5sities ( light f sev]al t]re/rial s\rces ( fairly well-kn[n temp]atures treat$ 9 ! same way4 ,^! e/imates yield$ to him a sol> temp]ature ( #gfjj ,c5t4 ,mo/ sci5ti/s reckon ) an absolute temp]ature ( #fejj1 correspond+ to ab\t #fbjj ,celsius4 ,t is :at is kn[n z ! 8effective temp]ature0 ( ! sun4 ,if ! sol> rays 7 n p>tially absorb$1 ?is temp]ature w\ld correspond to t ( ! cl\ds ( ! photosph]e4 ,s9ce r$ light is little absorb$ comp>atively1 ,le ,*ateli]'s value ( #gfjj1 & ! almo/ equal value ( ,wilson & ,gray ( #hjjj1 %\ld approximately repres5t ! av]age temp]ature ( ! out] portions ( ! cl\ds ( ! photosph]e4 ,! high] temp]ature ( ! facul is evid5t f _! great] light int5sity1 :i*1 h[ev]1 may p>tly be due to _! great] height4 ,c>r+ton & ,hodgson saw1 on ,septemb] #a1 #ahei1 two facul break out f ! edge ( a sun-spot4 ,_! spl5dor 0 five or six times great] ?an t ( ! surr\nd+ p>ts ( ! photosph]e4 ,t w\ld correspond to a temp]ature ( ab\t #aj1jjj or #ab1jjj ,c5t4 ,! deep] p>ts ( ! sun :i* broke out on ^! occasions evid5tly h a high] temp]ature1 & ?is is n unnatural1 s9ce ! sun is los+ heat by radiation f its out] portions4 ,we "k t ! temp]ature ( our atmosph]e decreases ) great] heights4 ,! movem5ts ( ! air are conc]n$ 9 ?is *ange4 ,a s9k+ mass ( air is compress$ by ! increas$ pressure to :i* x is be+ expos$1 & its temp]ature rises1 !re=e1 j z ! temp]ature rises 9 a pneumatic gas-light] :5 ! pi/on is press$ d[n4 ,if ! air 7 dry & 9 /rong v]tical motion1 its temp]ature w\ld *ange by #aj ,c5t4 7#ah ,f47 p] km4 ,if x /ood /ill1 x w\ld assume an almo/ uni=m temp]ature2 t is to say1 !re w\ld be no l[]+ ( ! temp]ature z we proce$ upw>d4 ,! actual value lies betwe5 ! two extremes4 ,z ! gravitation 9 ! photosph]e ( ! sun is #bg4d times great] ?an on ! surface ( ! e>?1 we c d$uce t1 if ! air on ! sun 7 z d5se z on ! e>?1 ! temp]ature on ! sun w\ld v>y #bg4d times z mu* z on ! e>? ) ! increas+ height--t is to say1 by #bgj degrees p] kilometre1 provid$ its atmosph]e 7 9 viol5t agitation4 ,n[1 ! out] portions ( ! sol> atmosph]e are1 inde$1 9 viol5t motion1 s t ?is latt] assumption seems to be ju/ifi$4 ,b ?is "p consi/s ess5tially ( hydrog51 :i* is #bi times light] ?an ! air4 ,we mu/1 !re=e1 r$uce ! value at :i* we arrive to "o-tw5ty-n9?4 ,z a result1 ! f9al temp]ature gradi5t p] kilometre w\ld only be #i ,c5t4 7#af4b ,f474 ,b ! radiation is extremely p[]ful on ! sun1 & x t5ds to equalize ! conditions4 ,n9e degrees p] kilometre is !re=e1 )\t d\bt1 too high a value4 ,fur!r1 9 ! int]ior ( ! sun ! gases are mu* heavi]4 ,at a small dep?1 h[ev]1 !y w be s /rongly compress$ by ! upp] /rata t _! fur!r compressibility w be limit$1 & ! calculation :i* we h j made loses its validity4 ,yet1 9 any case1 ! temp]ature ( ! sun mu/ increase z we p5etrate ne>] to its c5tre4 ,if we accept a temp]ature gradi5t p] kilometre ( ! value above indicat$1 #i--;x is ?ree times great] 9 ! solid e>?-cru/--we %\ld obta9 = ! c5tre ( ! sun a temp]ature ( m ?an six million degrees4 ,all sub/ances melt & evaporate z _! temp]ature is rais$4 ,if ! temp]ature exce$s a c]ta9 limit1 ! 8critical temp]ature10 ! sub/ance c no long] be cond5s$ to a liquid1 h[ev] high ! pressure may be pu%$1 & ! sub/ance w only exi/ z a gas4 ,if we />t f -#bgc z absolute z]o1 ?is critical temp]ature is ne>ly "o & a half times z high z ! ebullition temp]ature ( ! sub/ance "u atmosph]ic pressure4 ,s f> z our exp]i5ce goes1 x does n appe> probable t ! critical temp]ature ( any sub/ance c\ld be high] ?an #aj1jjj or #ab1jjj ,c5t41 ! highe/ values :i* we h calculat$ = ! temp]ature ( ! facul4 ,! inn] portions ( ! sun mu/ h5ce be gase\s1 & ! :ole sun be a /rongly compress$ mass ( gas ( extremely high temp]ature1 :i*1 ow+ to ! high pressure1 is at a d5sity #a4d times z great z t ( wat]1 & :i* 9 _m respects1 !re=e1 w resemble a liquid4 ,x mu/1 = in/ance1 be extremely viscid1 & t acc\nts = ! relatively great /ability ( ! sun-spots 7"o sun-spot held out = a ye> & a half 9 #ahdj & #ahda74 ,! sun w\ld ?us h to be reg>d$ z a sph]e ( gas1 9 ! out] portions ( :i* a c]ta9 am\nt ( cond5sations ( cl\d "* h tak5 place1 ow+ to radiation & to ! outw>d movem5ts ( ! gase\s masses4 ,! pressure 9 ! photosph]e--t is1 9 ^? p>ts 9 :i* ^! cl\ds are float+--has be5 av]ag$ at five or six atmosph]es1 a figure :i*1 consid]+ ! v high gravitation1 w\ld sugge/ a lay] ( sup]pos$ gas above x correspond+ to n m ?an a fif? ( our t]re/rial atmosph]e4 ,at an approximately correspond+ height1 #aa1ejj m4 7#ch1jjj ft471 !re are float+ 9 ! t]re/rial atmosph]e ! highe/ cirrus cl\ds1 to :i* ! cl\ds ( ! photosph]e may 9 _m respects be comp>$4 ,we turn back to ! unansw]$ "q :5ce ! sun takes ! comp5sation = ! heat :i* x con/antly radiates into space4 ,! mo/ p[]ful s\rce ( heat kn[n to u is t ( *emical reactions4 ,! mo/ famili> reaction ( daily life is ! combu/ion ( coal4 ,by burn+ "o gramme ( c>bon we obta9 #hjjj calories4 ,if ! sun consi/$ ( pure c>bon1 its en]gy w\ld n hold out m ?an #djjj ye>s4 ,x is n to be wond]$ at1 !re=e1 t mo/ sci5ti/s soon ab&on$ ! hope ( solv+ ! problem 9 ?is way4 ,! ,fr5* a/ronom] ,faye attempt$ to expla9 ! repl5i%m5t ( ! losses ( heat by radiation f ! sun by argum5ts 9 :i* he resort$ to ! heat ( a comb9ation ( ! con/itu5ts ( ! sun4 ,he said3 8,s high a temp]ature mu/ prevail 9 ! int]ior ( ! sun t ev]y?+ !re w be decompos$ into its elem5t>y con/itu5ts4 ,:5 ! atoms aft]w>ds p5etrate into ! out] lay]s1 !y are aga9 unit$1 & !y lib]ate heat40 ,faye ?us imag9$ t new masses ( elem5ts w\ld con/antly rise f ! int]ior ( ! sun & w\ld be reunit$ 9 *emical comb9ation on ! surface4 ,b if new masses are to p5etrate upw>d to ! surface1 ^? :i* 7 at fir/ above mu/ g back to ! c5tre ( ! sun1 9 ord] to be re-decompos$ by ! great heat !re2 & ?is re-decomposition w\ld consume j z mu* heat z 0 ga9$ by ! ris+ ( ! same masses to ! surface4 ,?is convection c !re=e only help to transport ! /ore ( heat f ! int]ior to ! surface4 ,! total am\nt ( heat /or$ 9 ! sun w\ld 9 ?is way1 suppos+ ! mean temp]ature to be six million degrees1 be able to cov] ! heat exp5diture = ab\t ?ree million ye>s4 ,we h1 moreov]1 se5 t ! highe/ /rata ( ! sun are di/+ui%$ by l9e spectra1 sugge/ive ( simple *emical comp\nds1 :ile at great] dep? 9 ! sun-spots *emical comb9ations occur :i* are *>act]iz$ by b& spectra4 ,x is q incorrect to ass]t t high temp]atures mu/ necess>ily decompose all *emical comp\nds into _! elem5ts4 ,! me*anical !ory ( heat tea*es u only t at ris+ temp]atures products are =m$ ^: =mation goes h& 9 h& ) an absorption ( heat4 ,?us1 at a high temp]ature1 ozone is =m$ f oxyg51 al?\gh ozone is m complex 9 composition ?an oxyg51 & by ?is reaction #gej calories are consum$ :5 "o gramme ( oxyg5 is trans=m$ into "o gramme ( ozone4 ,we likewise "k t 9 ! electric arc1 at a temp]ature ( ab\t #cjjj1 a comp\nd is =m$ "u consumption ( heat by ! oxyg5 & nitrog5 ( ! atmosph]e4 ,a new me?od = ! te*nical prep>ation ( nitric acid f ! nitrog5 ( ! air is bas$ ^u ?is reaction4 ,aga91 ! well-kn[n comp\nds b5z5e & acetyl5e are =m$ f _! elem5ts1 c>bon & hydrog51 "u absorption ( heat4 ,all ^! bodies c only be syn!siz$ f _! elem5t>y con/itu5ts at high temp]atures4 ,we fur!r "k f exp]i5ce t ! high] ! temp]ature at :i* a reaction takes place1 ! great]1 9 g5]al1 ! am\nt ( heat :i* x absorbs4 ,a simil> law applies to ! influ5ce ( pressure4 ,:5 ! pressure is increas$1 su* processes w be favor$ z w yield products ( a small] volume4 ,if we imag9e t a mass ( gas ru%es d[n f a high] /ratum ( ! sun into ! dep?s ( ! sun's int]ior1 z gases d 9 sun-spots1 complex comp\nds w be produc$ by virtue ( ! increas$ pressure4 ,?is pressure mu/ increase at an imm5se rate t[>ds ! int]ior ( ! sun1 by ab\t #cejj atmosph]es p] kilometre4 ,! gases :i* dissociate into atoms at ! l[] pressures & ! high] temp]atures ( ! extreme sol> /rata above ! photosph]e cl\ds ent] into *emical comb9ation 9 ! dep?s ( ! spots1 z we le>n f spectroscopic exam9ation4 ,ow+ to _! high temp]atures1 ^! comp\nds absorb enorm\s quantities ( heat 9 _! build+ up1 & ^! quantities ( heat are to ^? :i* are conc]n$ 9 ! *emical processes ( ! e>? 9 ! same ratio z ! temp]ature ( ! sun is to t at :i* ! *emical reactions are proce$+ on ! e>?4 ,z ^! gases p5etrate f>!r into ! sun1 temp]ature & pressure are /ill m & m increas$1 & !re w result products m & m ab\nd+ 9 en]gy & conc5tration4 ,we may1 !re=e1 imag9e ! int]ior ( ! sun *>g$ ) comp\nds :i*1 br\ght to ! surface ( ! sun1 w\ld dissociate "u an enorm\s evolution ( heat & an enorm\s increase ( volume4 ,^! comp\nds h to be reg>d$ z ! mo/ p[]ful bla/+ ag5ts1 by comp>ison ) :i* dynamite & gun-cotton w\ld appe> l toys4 ,9 confirmation ( ?is view1 we obs]ve t gases :5 p5etrat+ into ! photosph]e cl\ds are able to eject prom95ces at a /up5d\s velocity1 obta9+ sev]al hundr$ kilometres p] second4 ,?is velocity surpasses t ( ! swifte/ rifle-bullet ab\t a ?\s&fold4 ,we may h5ce ascribe to ! explosives :i* are conf9$ 9 ! int]ior ( ! sun en]gies :i* mu/ be a million times great] ?an ! en]gy ( our bla/+ ag5ts4 7,= ! en]gy increases ) ! squ>e ( ! velocity47 ,& yet ^! sol> bla/+ ag5ts h already giv5 up a l>ge "p ( _! en]gy dur+ _! passage f ! sun's int]ior4 ,x ?us becomes conceivable t ! sol> en]gy--in/ead ( hold+ out = #djjj ye>s1 z x w\ld if x dep5d$ ^u ! combu/ion ( a sol> sph]e made out ( c>bon--w la/ = some?+ l f\r ?\s& million ye>s4 ,p]haps we may fur!r ext5d ?is p]iod to sev]al billions4 ,t !re are su* en]getic comp\nds we h le>n$ f ! discov]y ( ! heat evolution ( radium4 ,accord+ to ,ru!r=d1 radium is decompos$ by "o-half 9 ! space ( ab\t #acjj ye>s4 ,9 ?is decomposition a quantity ( ab\t a million calories is evolv$ p] gramme & p] ye>1 & we ?us f9d t ! decomposition ( radium into its f9al products is accompani$ by a heat evolution ( ab\t two ?\s& millions ( calories p] gramme--ab\t a qu>t] ( a million times m heat ?an ! combu/ion ( "o gramme ( c>bon w\ld yield4 ,9 *emical respects z well1 !n1 ! e>? is a dw>f comp>$ to ! sun1 & we h e reason to presume t ! *emical en]gy ( ! sun w be suffici5t to su/a9 ! sol> heat dur+ _m ?\s& millions & possibly billions ( ye>s to come4 ,,iv ,,! ,,radiation ,,pressure ,next to simple measur+ & simple calculations1 a/ronomy appe>s to be ! mo/ anci5t sci5ce4 ,yet1 ?\gh man has wor%ipp$ ! sun f ! mo/ remote ages1 x 0 n fully compreh5d$ be=e ! middle ( ! pa/ c5tury t ! sun is ! s\rce ( all life & ( all motion4 ,"p ( ! v5]ation = ! sun 0 transf]r$ to ! moon1 ) its mild light1 & to ! small] cele/ial lights4 ,x did n escape notice t _! positions 9 ! sky 7 always *ang+ simultane\sly ) ! annual v>iations 9 ! wea!r1 & all human und]tak+s dep5d$ ^u ! wea!r & ! seasons4 ,! moon & ! />s 7 wor%ipp$--we "k n[1 )\t any ju/ification :atev]--z rul+ ov] ! wea!r1 & consequ5tly ov] man's fate4#f ,be=e any?+ 0 und]tak5 p attempt$ fir/ to assure !mselves ( ! favorable aspect ( ! con/ellations1 & s9ce ! mo/ remote ages a/rolog]s h ex]cis$ a va/ influ5ce ov] ! ignorant & sup]/iti\s multitude4 ,footnote #f3 ,! moon /rongly1 & m ?an any o!r ag5t1 influ5ces ! tides4 ,ap>t f ?is effect ! position ( ! moon has only a feeble influ5ce ^u ! air pressure & ^u atmosph]ic electricity & t]re/rial magnetism4 ,! influ5ce ( ! />s is imp]ceptible4 ,9 spite ( ! vehem5t enunciation ( ,giordano ,bruno 7#aedh-afjj71 ?is sup]/ition 0 /ill deeply root$ :5 ,newton succe$$ 9 prov+1 9 #afhf1 t ! movem5ts ( ! s-call$ w&]+ />s1 or planets1 & ( _! moons c\ld be calculat$ ) ! aid ( "o v simple law3 t all ^! cele/ial bodies are attract$ by ! sun or by _! respective c5tral bodies ) a =ce :i* is proportional to _! own mass & to ! mass ( ! c5tral body & inv]sely proportional to ! squ>e ( _! di/ance f t c5tral body4 ,newton's contempor>y1 ,halley1 appli$ ! law ( gravitation also to ! my/]i\s comets1 & calculat+ a/ronomy has s9ce be5 bas$ ^u ?is1 its firme/ law1 to :i* !re has n be5 f\nd any exception4 ,! _w 0 ?us at once rid ( ! p>alyz+ sup]/ition :i* exact$ belief 9 a my/]i\s rul+ ( ! />s4 ,! contempor>ies ( ,newton1 z well z _! desc5dants1 h rightly valu$ ?is discov]y m highly ?an any o!r sci5tific triumph ( ?is h]o's4 ,accord+ to ,newton's law1 all mat]ial bodies w\ld t5d to become m & m conc5trat$ & unit$1 & ! developm5t ( ! univ]se w\ld result 9 ! suck+ up ( ! small] cele/ial bodies--! meteorites1 = in/ance--by ! l>g] bodies4 ,x mu/1 h[ev]1 be rem>k$ t ,newton's great precursor1 ,kepl]1 obs]v$ 9 #afah t ! matt] ( ! comets is repell$ by ! sun4 ,l ,newton1 he believ$ 9 ! corpuscul> !ory ( light4 ,! sun & all o!r lum9\s bodies radiat$ light1 !y ?\ght1 because !y eject$ m9ute corpuscles ( light matt] 9 all directions4 ,if1 n[1 ^! small corpuscles hit aga9/ ! du/ p>ticles 9 ! comets' tails1 ! du/ p>ticles w\ld be c>ri$ away ) !m1 & _! repulsion by ! sun w\ld become intelligible4 ,x is *>act]i/ic t ,newton w\ld n admit ?is explanation ( ,kepl]'s1 al?\gh he %>$ ,kepl]'s op9ion on ! nature ( light4 ,accord+ to ,newton1 ! deviation ( ! tails ( comets f 8 law ( g5]al attraction 0 only app>5t4 ,! tails ( comets1 he argu$1 behav$ l ! columns ( smoke ris+ f a *imney1 :i*1 al?\gh ! gases ( combu/ion are attract$ by ! e>?1 yet asc5d because !y are light] ?an ! surr\nd+ air4 ,?is view1 :i* has be5 *>act]iz$ by ,newcomb z no long] to be s]i\sly tak5 into consid]ation1 demon/rates ! /rong t5d5cy ( ,newton to expla9 ev]y?+ ) ! aid ( 8 law4 ,! a/ronom]s foll[$ fai?fully 9 ! foot/eps ( _! inimitable ma/]1 ,newton1 & !y bru%$ aside e ph5om5on :i* w\ld n fit into 8 sy/em4 ,an exception 0 made by ! fam\s ,eul]1 :o1 9 #agdf1 express$ ! op9ion t ! waves ( light ex]t$ a pressure ^u ! body ^u :i* !y fell4 ,?is op9ion1 h[ev]1 c\ld n prevail aga9/ ! criticisms ) :i* o!rs1 & especially ,de ,mairan1 assail$ x4 ,t ,eul] 0 "r1 h[ev]1 0 prov$ by ,maxwell's great !oretical treatise on ! nature ( electricity 7#ahgc74 ,he %[$ t rays ( heat--& ! same applies1 z ,b>toli e/abli%$ 9 #ahgf1 to radiations ( any k9d--mu/ ex]cise a pressure j z great z ! am\nt ( en]gy conta9$ 9 a unit volume1 by virtue ( _! radiation4 ,maxwell calculat$ ! magnitude ( ?is pressure1 & he f\nd x s small t x c\ld h>dly h be5 demon/rat$ ) ! exp]im5tal means !n at our disposal4 ,b ?is demon/ration has s9ce be5 furni%$1 ) ! aid ( measurem5ts obta9$ 9 a vacuum1 by ! ,russian ,leb$eff & by ! ,am]icans ,ni*ols & ,hull 7#aijj1 #aija74 ,!y h f\nd t ?is pressure1 ! s-call$ radiation pressure1 is exactly z great z ,maxwell pr$ict$4 ,9 spite ( ,maxwell's great au?ority1 a/ronom]s q ov]look$ ?is important law ( 84 ,leb$eff1 inde$1 tri$ 9 #ahib to apply x to ! tails ( comets1 :i* he reg>d$ z gase\s2 b ! law is n applicable 9 ?is case4 ,z late z ! ye> #aijj1 %ortly be=e ,leb$eff 0 able to publi% 8 exp]im5tal v]ification ( ?is law1 ,i attempt$ to prove its va/ importance = ! explanation ( sev]al cele/ial ph5om5a4 ,! magnitude ( ! radiation pressure ( ! sol> atmosph]e mu/ be equival5t to #b4ge milligrammes if ! rays /rike v]tically aga9/ a black body "o squ>e c5timetre 9 area4 ,i also calculat$ ! size ( a sph]ule ( ! same specific gravity z wat]1 su* t ! radiation pressure to :i* x w\ld be expos$ 9 ! vic9ity ( ! sun w\ld balance ! attraction by ! sun4 ,x result$ t equilibrium w\ld be e/abli%$ if ! diamet] ( ! sph]e 7 #j4jjae mm4 ,a correction suppli$ by ,s*w>zs*ild %[$ t ! calculation 0 only valid :5 ! sph]e completely reflects all ! rays :i* fall ^u x4 ,if ! diamet] ( ! sph]ule be /ill small]1 ! radiation pressure w prevail ov] ! attraction1 & su* a sph]e w\ld be repell$ by ! sun4 ,ow+ to ! refraction ( light1 ?is w1 accord+ to ,s*w>zs*ild1 fur!r necessitate t ! circumf]5ce ( ! sph]ule %\ld be great] ?an #j4c times ! wave-l5g? ( ! incid5t rays4 ,:5 ! sph]e becomes /ill small]1 gravitation w once m pr$om9ate4 ,b sph]ules ^: sizes are int]m$iate betwe5 ^! two limits w be repell$4 ,x results1 !re=e1 t molecules1 :i* h f> small] dim5sions ?an ^? m5tion$1 w n be repell$ by ! radiation pressure1 & t !re=e ,maxwell's law does n hold = gases4 ,:5 ! circumf]5ce ( ! sph]ule becomes exactly equal to ! wave-l5g? ( ! radiation1 ! radiation pressure w act at its maximum1 & x w !n surpass gravity n less ?an n9ete5 times4 ,^! calculations apply to all sph]es1 totally reflect+ ! light1 ( a specific gravity l wat]1 & to a radiation & attraction correspond+ to t ( ! sun4 ,s9ce ! sunlight is n homog5e\s1 ! maximum effect w some:at be dim9i%$1 & x is ne>ly equal to t5 times ! gravity = sph]es ( a diamet] ( ab\t #j4jjjaf mm4#g ,footnote #g3 ,"o c5timetre ( wat] conta9s #dgj billions ( ^! sph]es4 ,su* a little drop ( wat]1 aga91 conta9s #if millions ( molecules1 & !re are probably organisms :i* are small] ?an ^! drops4 ,comp>e ! exp]im5ts ) ultra-microscopic organisms by ,e4 ,raehlmann1 ,n4 ,gaiduk[1 & o!rs4 ,be=e we _h rec\rse to ! radiation pressure = ! explanation ( ! repulsion ph5om5a su* z h be5 obs]v$ 9 ! tails ( comets1 x 0 g5]ally believ$ ) ,zlln] t ! repulsion 0 due to electrical =ces4 ,electricity und\bt$ly plays an important "p 9 ^! ph5om5a1 z we %all see4 ,! way 9 :i* x acts 9 ^! in/ances 0 expla9$ by a discov]y ( ,c4 ,t4 ,r4 ,wilson 9 #ahii4 ,gases c 9 v>i\s ways be trans=m$ into conductors ( electricity :i* z a rule !y d n conduct4 ,! conduct+ gases are said to be ioniz$--t is to say1 !y conta9 free ions1 m9ute p>ticles *>g$ ) positive or negative electricity4 ,gases c be ioniz$1 among o!r ways1 by be+ radiat$ ^u ) ,rntg5 rays1 ka?ode rays1 or ultra-violet light1 z well z by /rong heat4 ,s9ce ! light ( ! sun conta9s a great _m ultra-violet radiations1 x is indisputable t ! masses ( gases 9 ! neighborhood ( ! sun 7e4g41 probably 9 comets :5 !y come ne> ! sun7 w p>tly be ioniz$1 & w conta9 bo? positive & negative ions4 ,ioniz$ gases are end[$ ) ! rem>kable capability ( cond5s+ vapors ^u !mselves4 ,wilson %[$ t ?is prop]ty is possess$ to a high] degree by ! negative ions ?an by ! positive ions 79 ! cond5sation ( wat] vapor74 ,if !re are1 !re=e1 wat] vapors 9 ! neighborhood ( ! sun :i* c be cond5s$ by cool+1 drops ( wat] w1 9 ! fir/ in/ance1 be cond5s$ ^u ! negative ions4 ,:5 ^! drops are aft]w>ds repell$ by ! radiation pressure1 or :5 !y s9k1 ow+ to gravity1 z drops ( ra9 s9k 9 ! t]re/rial atmosph]e1 !y w c>ry ) !m ! *>ge ( ! negative ions1 :ile ! correspond+ positive *>ge w rema9 beh9d 9 ! gas or 9 ! air4 ,9 ?is way ! negative & positive *>ges w become sep>at$ f ea* o!r1 & electric dis*>ges may ensue if suffici5tly l>ge quantities ( opposite electricity h be5 accumulat$4 ,by reason ( ^! dis*>ges ! gases w become lum9esc5t1 al?\gh _! temp]ature may be v l[4 ,/>k has ev5 %[n t l[ temp]atures are favorable = ! display ( a /rong lum9osity 9 electric dis*>ges4 ,we h /at$ t ,kepl]1 z e>ly z ! beg9n+ ( ! sev5te5? c5tury1 came to ! conclusion t ! tails ( comets 7 repell$ by ! sun4 ,newton indicat$ h[ we might1 f ! %ape ( ! comets' tails1 calculate _! velocity4 ,! be/ way1 h[ev]1 is to det]m9e ?is velocity by direct obs]vation4 ,! comets' tails are n s uni=m 9 appe>ance z !y are g5]ally repres5t$ 9 illu/rations1 b !y (t5 conta9 sev]al lum9\s nuclei 7,fig4 #cc71 ^: motions c be directly asc]ta9$4 ,illu/ration3 ,fig4 #cc4--,photograph ( ,ro]dam's comet 7#ahic ,,ii471 sugge/+ sev]al /rong nuclei 9 ! tail ,f a /udy ( ! movem5ts ( comets' tails1 ,olb]s conclud$1 ab\t ! beg9n+ ( ! la/ c5tury1 t ! repulsion ( ! comets' tails by ! sun is inv]sely proportional to ! squ>e ( _! di/ance--t is to say1 t ! =ce ( ! repulsion is subject to ! same law z ! =ce ( gravitation4 ,we c1 !re=e1 express ! repulsion effect 9 units ( sol> gravitation1 & ?is has g5]ally be5 done4 ,t ! radiation pressure w 9 ! same mann] *ange ) ! di/ance is only natural4 ,= ! radiation aga9/ ! same surface is also inv]sely proportional to ! squ>e ( ! di/ance f ! radiat+ body1 ! sun4 ,illu/ration3 ,fig4 #cd4--,photograph ( ,swift's comet 7#ahib ,i47 ,9 ! latt] "p ( ! pa/ c5tury ! ,russian a/ronom] ,br$i*9 conduct$ a great _m measurem5ts on ! magnitude ( ! =ces ) :i* comets' tails are repell$ by ! sun4 ,he consid]$ himself1 on ! /r5g? ( ^! measurem5ts1 ju/ifi$ 9 divid+ comets' tails into ?ree classes4 ,9 ! fir/ class ! repulsion 0 #ai times /rong] ?an gravitation2 9 ! second class1 f #c4b to #a4e times /rong]2 & 9 ! ?ird class1 f #a4c to #a times /rong]4 ,/ill high] values h1 h[ev]1 be5 d$uc$ = sev]al comets4 ,?us ,hussey f\nd = ! comet ( #ahic 7,ro]dam's comet1 #ahic ,,ii41 ,fig4 #cc7 a repulsion #cg times z /rong z gravitation2 & ,swift's comet 7#ahib ,i47 yields ! /ill high] value ( #dj4e 7,fig4 #cd74 ,"s comets %[ sev]al tails ( diff]5t k9ds1 z ! fam\s comet ( ,donati 7,fig4 #ce74 ,its two almo/ /raight tails w\ld belong to ! fir/ class1 & ! m /rongly develop$ & curv$ ?ird tail to ! second class4 ,illu/ration3 ,fig4 #ce4--;,donati's comet at its greate/ brilliancy 9 #aheh ,s*w>zs*ild1 z already /at$1 calculat$ t small sph]ules reflect+ all ! incid5t light & ( ! specific gravity ( wat] w\ld be repell$ by ! sun ) a =ce t might balance t5 times _! weight4 ,= a sph]ule absorb+ all ! light fall+ ^u x ?is figure w\ld be r$uc$ to five times ! weight4 ,! small p>ticles ( comets :i*1 accord+ to spectroscopic obs]vations1 probably consi/ ( hydroc>bons are n p]fectly absorb+1 b !y p]mit c]ta9 rays ( ! sun to pass4 ,a clos] calculation %[s t 9 ?is case =ces ( ab\t #c4c times ! gravity w\ld result4 ,l>g] sph]ules yield small] values4 ,br$i*9's second & ?ird classes w\ld ?us be well adapt$ to meet ! requirem5ts :i* ! radiation pressure dem&s4 ,x is m difficult to expla9 h[ su* great =ces ( repulsion z ^? ( ! fir/ gr\p ( ,br$i*9 or ( ! peculi> comets ( ,swift & ( ,ro]dam c occur4 ,:5 a p>ticle or drop ( "s hydroc>bon is expos$ to p[]ful radiation1 x may f9ally become s int5sely heat$ t x w be c>boniz$4 ,x w yield a spongy coal1 because gases 7*iefly hydrog57 w escape dur+ ! c>bonization1 & ! p>ticles ( coal w resemble ! little gra9s ( coal-du/ :i* fall f ! smoke/acks ( our /eamboats1 & :i* aft]w>ds float on ! surface ( ! wat]4 ,x is q conceivable t su* sph]ules ( coal 7consi/+ probably ( s-call$ m>gu]ites1 felt$ or pe>ly /ructures resembl+ *a9s ( bacilli7 may h a specific gravity ( #j4a1 if we make all[ance = ! gases !y include 7comp>e page #ajf47 ,a light-absorb+ drop ( ?is d5sity ( #j4a might1 9 ! mo/ favorable case1 exp]i5ce a repulsion =ty times z /rong z ! gravitation ( ! sun4 ,9 ?is mann] we c picture to ourselves ! possibility ( ! greate/ obs]v$ =ces ( repulsion4 ,! spectra ( comets confirm 9 e respect ! conclusions to :i* ! !ory ( ! radiation pressure leads up4 ,!y display a fa9t1 cont9u\s spectrum :i* is probably due to sunlight reflect$ by ! small p>ticles4 ,besides ?is1 we obs]ve1 z already m5tion$1 a spectrum ( gase\s hydroc>bons & cyanog54 ,^! b& spectra are due to electric dis*>ges2 = !y are obs]v$ 9 comets ^: di/ance f ! sun is s great t !y _c appe> lum9\s ow+ to _! own high temp]atures4 ,9 ! tail ( ,swift's comet b&$ spectra h be5 obs]v$ 9 portions :i* 7 ab\t five million kilometres f ! nucleus4 ,! electric dis*>ges mu/ *iefly be emitt$ f ! out] p>ts ( ! tails1 :]e1 accord+ to ! laws ( /atic electricity1 ! electric =ces w\ld be /ronge/4 ,= ?is reason ! l>g] tails ( comets look z if !y 7 envelop$ 9 cloaks ( light ( a m int5se lum9osity4 ,illu/ration3 ,fig4 #cf4--;,imitation ( comets' tails4 ,exp]im5t by ,ni*ols & ,hull4 ,! light ( an arc-lamp is conc5trat$ by a l5s ^u ! /ream ( f9ely p[d]$ p>ticles ,:5 a comet comes ne>] to ! sun1 o!r less volatile bodies also beg9 to evaporate4 ,we !n f9d ! l9es ( sodium &1 :5 ! comet comes v close to ! sun1 also ! l9es ( iron 9 its spectrum4 ,^! l9es are evid5tly produc$ by sub/ances :i* h be5 evaporat$ f ! nucleus ( ! comet4 ,l ! meteorites fall+ ^u our e>?1 ! nucleus w consi/ ess5tially ( silicates1 & p>ticul>ly ( ! silicate ( sodium1 &1 fur!r1 ( iron4 ,we c easily imag9e h[ ! tails ( comets *ange 9 appe>ance4 ,:5 a comet draws ne> to ! sun1 we obs]ve t matt] is eject$ f t "p ( ! nucleus :i* is turn$ t[>ds ! sun4 ,! case is analog\s to ! =mation ( cl\ds 9 ! t]re/rial atmosph]e on a hot summ] day4 ,! cl\ds are provid$ ) a k9d ( hood :i* envelops l a ?91 semi-sph]ical veil t side ( ! nucleus :i* turns to ! sun4 ,sometimes we obs]ve two or m hoods correspond+ to ! diff]5t lay]s ( cl\ds 9 ! t]re/rial atmosph]e4 ,f ! f>!r side ( ! hood matt] /reams away f ! sun4 ,! tails ( comets are usually m highly develop$ :5 !y approa* ! sun ?an :5 !y rec$e f x4 ,t may be1 z has be5 assum$ = a long "t1 because a l>ge "p ( ! hydroc>bons w become exhau/$ :ile ! comet passes ! sun4 ,we h also notic$ t ! s-call$ p]iodical comets1 :i* return to ! sun at regul> int]vals1 %[$ at e reappe>ance a fa9t] developm5t ( ! tail4 ,comets1 fur!r1 %9e at _! greate/ brilliancy 9 p]iods ( /rong sol>-spot activity4 ,we may1 !re=e1 assume t 9 ^? p]iods ! surr\nd+s ( ! sun are *>g$ to a relatively high degree ) ! f9e du/ :i* c s]ve z a cond5sation nucleus = ! matt] ( ! comets' tails4 ,x is also probable t 9 su* p]iods ! ioniz+ radiation ( ! sun is m pron\nc$ ?an usual1 ow+ to ! simultane\s pr$om9ance ( facul4 ,ni*ols & ,hull h attempt$ to imitate tails ( comets4 ,!y heat$ ! spores ( ! fungus ,lycop]don bovi/a1 :i* are almo/ sph]ical & ( a diamet] ( ab\t #j4jjb mm41 up to a r$ gl[1 & !y ?us produc$ little spongy balls ( c>bon ( an av]age d5sity ( #j4a4 ,^! !y mix$ ) em]y-p[d] & introduc$ !m into a glass vessel resembl+ an h\r-glass 7,fig4 #cf7 f :i* ! air _h previ\sly be5 exhau/$ z f> z possible4 ,!y !n caus$ ! p[d]$ mass to fall 9 a f9e /ream into ! l[] "p ( ! vessel :ile expos+ x at ! same "t to ! conc5trat$ light ( an arc-lamp4 ,! em]y p>ticles fell p]p5dicul>ly to ! bottom1 :ile ! little balls ( c>bon 7 driv5 aside by ! radiation pressure ( ! light4 ,we also meet ) ! effects ( ! radiation pressure 9 ! imm$iate neighborhood ( ! sun4 ,! rectil9e> ext5sion ( ! corona /ream]s to a di/ance :i* has be5 kn[n to exce$ six times ! sol> diamet] 7ab\t eight million km47 indicates t repell+ =ces f ! sun are act+ ^u ! f9e du/4 ,a/ronom]s h also comp>$ ! corona ( ! sun ) ! tails ( comets1 & ,donits* w\ld class x ) ,br$i*9's comets' tails ( ! second class4 ,x is possible to calculate ! mass ( ! corona f its radiation ( heat & light4 ,! heat radiat$ has be5 measur$ by ,abbot4 ,at a di/ance ( #cj1jjj km4 f ! photosph]e1 ! corona radiat$ only z little heat z a body at -#ee ,c5t4 ,! reason is t ! corona 9 ^! p>ts consi/s ( an extremely att5uat$ mi/ ^: actual temp]ature c be e/imat$ by ,/efan's law at #dcjj ,c5t4 ,! corona mu/1 !re=e1 be s att5uat$ t x w\ld only cov] a #aij1jjj? "p ( ! sky beh9d x4 ,we arrive at ! same result :5 we calculate ! am\nt ( light radiat$ by ! corona2 ?is radiation is ( ! ord] ( t ( ! full moon1 be+ sometimes small]1 sometimes great]1 up to twice z great4 ,! consid]ations we h be5 (f]+ apply to ! mo/ int5se "p ( ! corona1 ! s-call$ inn] corona4 ,accord+ to ,turn]1 its light int5sity outw>d dim9i%es 9 ! inv]se ratio ( ! six? p[] ( its di/ance f ! c5tre ( ! sun4 ,at ! di/ance ( a sol> radius 7#fij1jjj km47 ! light int5sity w\ld !re=e be only #a4f p] c5t4 ( ! int5sity ne> ! surface ( ! sun4 ,let u assume t ! matt] ( ! corona consi/s ( p>ticles ( j su* a size t ! radiation pressure w\ld balance _! weight 7o!r p>ticles w\ld be expell$ f ! inn] corona72 !n we f9d t ! weight ( ! :ole corona ( ! sun w\ld n exce$ twelve million metric tons4 ,t is n m ?an ! weight ( f\r hundr$ ( our l>ge ocean /eam%ips 7e4g41 ! ,oceanic71 & only ab\t z mu* z ! quantity ( coal burn$ on ! e>? )9 "o week4 ,t ! mass ( ! corona mu/ be extremely r>efi$ has already be5 conclud$1 f ! fact t comets h w&]$ ?r\gh ! corona )\t be+ visibly arre/$ 9 _! motion4 ,9 #ahdc a comet pass$ ! sun's surface at a di/ance ( only "o-qu>t] ! sun's radius )\t be+ di/urb$ 9 its progress4 ,m\lton calculat$ t ! great comet ( #ahha1 :i* approa*$ ! sun )9 "o-half its radius1 did n enc\nt] a resi/ance ( m ?an "o-fifty-?\s&? ( its mass1 & t ! nucleus ( ! comet 0 at lea/ five million times d5s] ?an ! matt] ( ! corona4 ,newcomb has possibly express$ ! degree ( att5uation ( ! corona 9 a some:at exagg]at$ way :5 he said t x conta9s p]haps "o gra9 ( du/ p] cubic kilometre 7a cube ^: side has a l5g? ( ?ree-fif?s ( a mile74 ,h[ev] small ! quantity ( matt] 9 ! corona may be1 & h[ev] unimportant a fraction ( ?is mass may pass into ! coronal rays1 x is yet c]ta9 t !re is a con/ant loss ( f9ely divid$ matt] f ! sun4 ,! loss1 h[ev]1 is n great] ?an ! supply ( matt] 7comp>e bel[7--namely1 ab\t #cjj ?\s& millions ( tons 9 a ye>--s t dur+ "o billion ye>s n ev5 "o-six-?\s&? ( ! sol> mass 7#b #ajbg tons7 w be scatt]$ into space4 ,?is numb] is v unreliable1 h[ev]4 ,we "k t _m meteorites fall ^u ! e>?1 p>tly z compact /ones1 p>tly z ! f9e/ du/ ( %oot+-/>s :i* fla% up 9 ! t]re/rial atmosph]e rapidly to be ext+ui%$4 ,^! masses may be e/imat$ at ab\t #bj1jjj tons p] ye>4 ,accord+ to ?is e/imate1 ! ra9 ( meteorites :i* falls ^u ! sun may am\nt to #cjj ?\s& millions ( tons 9 a ye>4 ,all ! suns h emitt$ matt] into space = inf9ite ages1 & x seems1 !re=e1 a natural inf]5ce t _m suns w\ld no long] be 9 exi/5ce if !re _h n be5 a supply ( matt] to make up = ?is loss4 ,! cold suns und]go relatively small losses1 b receive j z l>ge infl[s ( matt] z ! w>m suns4 ,z1 n[1 our sun belongs to ! cold] type ( />s1 x is probable t ! loss ( matt] f ! sun has = ?is reason be5 ov]e/imat$ by be+ presum$ to be z great z ! accession4 ,! pres5ce ( d>k cele/ial bodies may comp5sate = ?is ov]e/imation4 ,illu/ration3 ,fig4 #cg4--;,granul> *ondrum f ! meteorite ( ,sexes4 ,enl>gem5t #a3 #gj4 ,aft] ,s4 ,ts*]mak ,:5ce d ! meteorites come8 ,if !y 7 n con/antly be+ creat$1 _! numb] %\ld h dim9i%$ 9 ! c\rse ( ages2 = !y are gradually be+ caught up by ! l>g] cele/ial bodies4 ,x is n at all improbable t !y arise f ! accresc5ce ( small p>ticles :i* ! radiation pressure has be5 driv+ out ( ! sun4 ,! *ondri1 :i* are s *>act]i/ic ( meteorites1 display a /ructure z if !y _h gr[n toge!r out ( a multitude ( extremely f9e gra9s 7,fig4 #cg74 ,nord5skild says3 8,mo/ meteoric iron consi/s ( an extremely delicate texture ( v>i\s alloys ( metals4 ,?is mass ( meteoric iron is (t5 s por\s t x oxidizes on exposure to ! air l spongy iron4 ,! ,pallas iron1 :5 cut ?r\gh ) a saw1 %[s ?is prop]ty1 :i* is s di/ress+ = ! collector4 ,! iron ( ,cranb\rne1 ( ,toluca1 & o!rs--9 fact1 almo/ all ! meteorites ) a few exceptions--display ! same texture4 ,x all indicates t ^! cosmical masses ( iron 7 built up 9 ! univ]se by p>ticle be+ pil$ ^u p>ticle1 ( iron1 nickel1 phosphorus1 etc41 analog\s to ! mann] 9 :i* "o atom ( a metal coalesces ) ano!r atom :5 ! metal is galvanically deposit$ f a solution4 ,mo/ ( ! /ony meteorites pres5t a simil> appe>ance4 ,ap>t f ! cru/ ( slag on ! surface1 ! /one is (t5 s por\s & s loose t x might be us$ z a filt]+ mat]ial1 & x may easily be crumbl$ betwe5 ! f+]s40 ,:5 ! electrically *>g$ gra9s ( du/ coalesce1 _! small electrical pot5tial 7( ab\t #j4jb volt7 may increase consid]ably4 ,"u ! influ5ce ( ultra-violet light ^! masses ( meteorites are dis*>g$ :5 !y approa* ! sun1 z ,l5>d has %[n4 ,_! negative *>ge !n escapes 9 ! %ape ( s-call$ electrons4 ,s9ce1 n[1 ! sun loses ?r\gh ! rays ( ! corona l>ge multitudes ( p>ticles1 & ^! p>ticles probably c>ry1 accord+ to ,wilson1 negative electricity ) !m1 ! positive *>ge mu/ rema9 beh9d 9 ! /ratum f :i* ! coronal rays 7 emitt$1 & also on ! sun itself4 ,if ?is *>ge 7 suffici5tly p[]ful1 x w\ld prev5t ! negatively *>g$ p>ticles 9 ! corona f escap+ f ! sun1 & all ! ph5om5a :i* we h ascrib$ to ! radiation pressure w\ld cease4 ,by ! aid ( ! t5ets ( ! mod]n !ory ( electrons1 ,i h calculat$ ! maximum *>ge t ! sun c\ld be>1 if x is n to /op ^! ph5om5a4 ,! *>ge w\ld am\nt to two hundr$ ?\s& millions ( c\lombs--n by any means too l>ge a quantity ( electricity1 z x w\ld only be suffici5t to decompose tw5ty-f\r tons ( wat]4 ,by means ( ?is positive *>ge ! sun ex]ts a va/ attractive p[] ^u all negatively *>g$ p>ticles :i* come ne> x4 ,we h already rem>k$ t ! gra9s ( sun-du/ :i* h unit$ to =m meteorites lose "u ! influ5ce ( ultra-violet light _! *>ge 9 ! %ape ( negative electrons1 extremely m9ute p>ticles1 ( :i* p]haps "o ?\s& weigh z mu* z "o atom ( hydrog5 7#a gramme ( hydrog5 conta9s ab\t #ajbd atoms1 correspond+ to #ajbg electrons74 ,^! electrons w&] ab\t 9 space4 ,:5 !y approa* a positively *>g$ cele/ial body !y are attract$ by x ) great =ce4 ,if ! electrons 7 mov+ ) a velocity ( #cjj km4 p] second1 z 9 ,l5>d's exp]im5t1 & if ! sun 7 *>g$ to "o-t5? ! maximum am\nt j calculat$1 x w\ld be able to draw up all ! electrons ^: rectil9e> pa? 7s f> z n curv$ by ! sun's attraction7 w\ld lie at a di/ance f ! sun #abe times z great z ! di/ance betwe5 ! sun & its mo/ remote planet1 ,neptune1 & #chjj times z great z ! di/ance betwe5 ! sun & ! e>?1 :i*1 aft] all1 w\ld only be "o-sixtie? ( ! di/ance f our ne>e/ fix$-/> neighbor4 ,! sun dra9s1 s to speak1 its surr\nd+s ( negative electricity1 & ?is dra9+ effect c>ries to ! sun1 z c\ld easily be prov$1 a quantity ( electricity :i* is directly dep5d5t ^u ! positive *>ge ( ! sun4 ,?us1 s f> z electricity is conc]n$1 ample provision has be5 made = ma9ta9+ equilibrium betwe5 ! income & exp5diture ( ! sun4 99 99 99 99 99 ,:5 an electrical p>ticle ent]s into a magnetic field x describes a spiral ab\t ! s-call$ magnetic l9es ( =ce2 :5 at a great] di/ance1 ! p>ticles appe> to move 9 ! direction ( ! l9es !mselves4 ,! rays ( ! corona emanat+ f ! sol> poles %[ a di/9ct curvature l t ( ! l9es ( =ce ab\t a magnet1 & = ?is reason ! sun has be5 reg>d$ z a big magnet ^: magnetic poles ne>ly co9cide ) ! geographical poles4 ,! coronal rays ne>] ! equator likewise %[ ?is curvature 7comp>e ,fig4 #cj74 ,! repell+ =ce ( ! radiation pressure !re is1 h[ev]1 at "r angles to ! l9es ( =ce & mu* /rong] ?an ! magnetic =ce1 s t ! rays ( ! corona are compell$ to =m two big /reams fl[+ 9 ! equatorial direction4 ,?is is especially noticeable at times ( sun-spot m9ima4 ,dur+ ! times ( sun-spot maxima ! /r5g? ( ! radiation pressure ( ! initial velocity ( ! gra9s ( du/ seem to pr$om9ate s m>k$ly t ! magnetic =ce is relatively small4 ,! a/ronom]s tell u t ! sun is only a /> ( small light int5sity comp>$ to ! prom95t />s :i* excite our admiration4 ,! sun fur!r belongs to a gr\p ( relatively cold />s4 ,we may easily imag9e1 !re=e1 t ! radiation pressure 9 ! vic9ity ( ^! l>g] />s w be able to move mu* l>g] masses ( matt] ?an 9 our sol> sy/em4 ,if ! diff]5t />s _h at any "t consi/$ ( diff]5t *emical elem5ts1 ?is diff]5ce w\ld h be5 equaliz$ 9 ! c\rse ( ages4 ,! meteorites may be reg>d$ z samples ( matt] collect$ & despat*$ f all possible divisions ( space4 ,n[1 :at bodies d we f9d 9 !m8 ,9 ! comets 7comp>e page #ajd7 iron1 sodium1 c>bon1 hydrog51 & nitrog5 7z cyanog57 play ! mo/ important "p4 ,we "k1 especially f ! rese>*es ( ,s*iap>elli t meteorites (t5 repres5t fragm5ts ( comets1 & mu/ !re=e be relat$ to !m4 ,?us ,biela's comet1 :i* _h a p]iod ( #f4f ye>s1 has disappe>$ s9ce #aheb--;x _h divid$ into two p>ts 9 #ahdd-ahde4 ,! comet 0 r$iscov]$ 9 a belt ( meteorites ( ! same p]iod :i* approa*es ! orbit ( ! e>? ea* ye> on ,novemb] #bg4 ,simil> relations h be5 obs]v$ ) reg>d to sev]al o!r sw>ms ( meteorites4 ,we "k also t ! j-m5tion$ elem5ts :i* spectrum analysis has prov$ to exi/ 9 comets are ! ma9 con/itu5ts ( ! meteorites1 :i*1 9 addition1 conta9 ! metals calcium1 magnesium1 alum9ium1 nickel1 cobalt1 & *romium1 z well z ! metalloids oxyg51 silicon1 sulphur1 phosphorus1 *lor9e1 ars5ic1 argon1 & helium4 ,_! composition /rongly recalls ! volcanic products ( s-call$ basic nature--t is to say1 ^? :i* conta9 relatively l>ge proportions ( metallic oxides1 & :i* h be5 ?\ght = good reasons to hail f ! deep] /rata ( ! int]ior ( ! e>?4 ,locky] heat$ meteoric /ones 9 ! electric arc to inc&esc5ce & f\nd _! spectra to be v simil> to ! sol> spectrum4 ,we !re=e draw ! conclusion t ^! mess5g]s f o!r sol> sy/ems :i* br+ u samples ( _! *emical elem5ts are closely relat$ to our sun & to ! int]ior ( our e>?4 ,t o!r />s & comets are ess5tially compos$ ( ! same elem5ts z our sun & e>?1 spectrum analysis _h already intimat$ to u4 ,b v>i\s metalloids1 l *lor9e1 brom9e1 sulphur1 phosphorus1 & ars5ic1 :i* are ( importance = ! composition ( ! e>?1 h s f> n be5 trac$ 9 ! spectra ( ! cele/ial bodies1 nor 9 t ( ! sun4 ,we f9d !m 9 meteorites1 h[ev]1 & !re is n ! slighte/ d\bt t we mu/ likewise c\nt !m among ! ess5tial con/itu5ts ( ! sun & o!r cele/ial bodies4 ,x is ) difficulty1 h[ev]1 t ! metalloids c be made to exhibit _! spectra1 & ?is is manife/ly ! reason :y spectrum analysis has n yet succe$$ 9 e/abli%+ _! pres5ce 9 ! heav5s4 ,z reg>ds ! rec5tly discov]$ s-call$ noble gases helium1 argon1 neon1 krypton1 & x5on1 _! pres5ce 9 ! *romosph]e has be5 discov]$ on spectrograms tak5 dur+ eclipses ( ! sun 7,/assano74 ,accord+ to ,mit*ell1 h[ev]1 ^! /atem5ts w\ld appe> to be some:at unc]ta9 z to krypton & x5on4 ,! small p>ticles ( du/ :i* ! radiation pressure drives out into space to all possible di/ances f ! sun & ! />s may hit aga9/ "o ano!r & may accumulate to l>g] or small] aggregates 9 ! %ape ( cosmical du/ or meteorites4 ,^! aggregates w p>tly fall ^u o!r />s1 planets1 comets1 or moons1 & p>tly--& ?is 9 v great multitudes--!y w float ab\t 9 space4 ,!re !y may1 toge!r ) ! l>g] d>k cele/ial bodies1 =m a k9d ( haze1 :i* p>tly hides f u ! light ( di/ant cele/ial bodies4 ,h5ce we d n see ! :ole sky cov]$ ) lum9\s />s1 :i* w\ld be ! case if1 z we may surmise1 ! />s 7 uni=mly di/ribut$ all ?r\gh ! inf9ite space ( ! univ]se1 & if !re 7 no ob/acle to _! emission ( light4 ,if !re 7 no o!r cele/ial bodies ( v l[ temp]ature & v l>ge dim5sions :i* absorb$ ! heat ( ! bright suns1 ! d>k cele/ial bodies1 ! meteorites1 & ! d>k cosmical du/ w\ld soon be s /rongly heat$ by sol> radiation t !y w\ld !mselves turn inc&esc5t1 & ! :ole dome ( ! sky w\ld appe> to u l "o gl[+ vault ^: hot radiation d[n to ! e>? w\ld soon burn e liv+ ?+4 ,^! o!r cold cele/ial bodies :i* absorb ! sol> rays )\t !mselves becom+ hot are kn[n z nebul4 ,m rec5t rese>*es make u believe t ^! peculi> cele/ial bodies occur ne>ly ev]y:]e 9 ! sky4 ,! wond]ful me*anism :i* enables !m to absorb heat )\t rais+ _! own temp]ature w be expla9$ lat] 79 ,*apt] ,,vii474 ,z ^! cold nebul occupy va/ portions ( space1 mo/ ( ! cosmical du/ mu/ f9ally1 9 its w&]+s ?r\gh inf9ite space1 /ray into !m4 ,?is du/ w !re meet masses ( gases :i* /op ! p5etration ( ! small corpuscles4 ,z ! du/ is electrically *>g$ 7p>ticul>ly ) negative electricity71 ^! *>ges w also be accumulat$ 9 ! out] lay]s ( ! nebul4 ,?is w proce$ until ! electrical t5sion becomes s /rong t dis*>ges are />t$ by ! ejection ( electrons4 ,! surr\nd+ gases w !re=e be r5d]$ lum9esc5t1 al?\gh _! temp]ature may n mu* 7p]haps by #ej7 exce$ absolute z]o1 -#bgc ,c5t41 & 9 ?is way we are enabl$ to obs]ve ^! nebul4 ,mo/ ( ! p>ticles w be /opp$ be=e !y h _h "t to p5etrate v deeply into a nebula1 & x w !re=e pr9cipally be ! out] portions ( ! nebul :i* s5d _! light to u4 ,t w\ld con=m to ,h]s*el's description ( planet>y nebul1 :i* display no great] lum9osity 9 _! c5tres1 b :i* %9e z if !y =m$ holl[ sph]ical %ells ( nebul\s matt]4 ,x is v easy to demon/rate t only sub/ances1 su* z helium & hydrog51 :i* are mo/ difficult to cond5se1 c at ?is l[ temp]ature exi/ 9 gase\s =m to any noticeable degree4 ,! nebul1 !re=e1 %9e almo/ exclusively 9 ! light ( ^! gases4 ,!re occurs 9 ! nebul1 9 addition to ^! gases1 a my/]i\s sub/ance1 nebulium1 ^: peculi> spectrum has n be5 f\nd on ! e>? nor 9 ! light ( />s4 ,=m]ly ! "* ( ! nebul> spectrum 0 expla9$ by ! assumption ei!r t no o!r bodies occurr$ 9 nebul ?an ! sub/ances m5tion$1 or t all ! o!r elem5ts 9 !m 7 decompos$ into hydrog5--helium 0 n kn[n !n4 ,! simple explanation is t only ! gases ( ! out] lay] ( ! nebul are lum9\s4 ,h[ _! int]iors are con/itut$1 we d n "k4 ,x has be5 object$ to ! view j express$ t ! :ole sky %\ld gl[ 9 a nebul\s light1 & t ev5 ! out] atmosph]e ( ! e>? %\ld display su* a gl[4 ,b hydrog5 & helium occur only v sp>ely 9 ! t]re/rial atmosph]e4 ,we f9d1 h[ev]1 ano!r light1 ! s-call$ auroral l9e1 :i* may possibly be due to krypton 9 our atmosph]e4 ,:i*ev] way we turn ! spectroscope on a v cle> night1 especially 9 ! tropics1 we obs]ve ?is peculi> gre5 l9e4 ,x 0 =m]ly consid]$ to be *>act]i/ic ( ! ,zodiacal ,light1 b on a clos] exam9ation x has be5 trac$ all ov] ! sky1 ev5 :]e ! ,zodiacal ,light c\ld n be obs]v$4 ,"o ( ! objections to our view is !re=e unju/ifi$4 ,z reg>ds ! o!r objection1 we h to rem>k t any light emission mu/ exce$ a c]ta9 m9imum int5sity to become visible4 ,!re may be nebul1 & !y probably con/itute ! majority1 :i* we _c obs]ve because ! numb] ( electrically *>g$ p>ticles ru%+ into !m is f> too insignificant4 ,a confirmation ( ?is view 0 furni%$ by ! fla%+-up ( ! new /> 9 ,p]seus on ,febru>y #ba & #bb1 #aija4 ,?is /> eject$ two diff]5t k9ds ( p>ticles1 ( :i* ! "o k9d travell$ ) ne>ly d\ble ! velocity ( ! o!r4 ,! accumulations ( du/ =m$ two sph]ical %ells ar\nd ! new />1 correspond+ 9 e respect to ! two k9ds ( comets' tails ( ,br$i*9's fir/ & second classes1 :i* we h sometimes obs]v$ toge!r 9 ! same comet 7,fig4 #ce74 ,:5 ^! du/ p>ticles1 on _! road1 hit aga9/ nebul> masses1 ! latt] became lum9esc5t1 & we !reby obta9$ k ( ! pres5ce ( l>ge /ell> nebul ( ^: exi/5ce we previ\sly _h n ! fa9te/ suspicion4 ,conditions1 no d\bt1 are simil> 9 o!r p>ts ( ! heav5s :]e 8we h n s f> discov]$ any nebul--we believe1 because ( ! small numb] ( ^! *>g$ p>ticles /ray+ ab\t 9 ^? p>ts4 ,on ! same gr\nds we may expla9 ! v>iability ( c]ta9 nebul :i* =m]ly appe>$ q enigmatical40 ,v ,,! ,,sol> ,,du/ ,,9 ,,! ,,atmosph]e--,,pol> ,,lights ,,& ,,! ,,v>iations ,,( ,,t]re/rial ,,magnetism ,we h s f> dwelt on ! effects :i* ! p>ticles expell$ f ! sun & ! />s ex]t on di/ant cele/ial bodies4 ,x may be ask$ :e!r ?is du/ does n act ^u our own e>?4 ,we h already recogniz$ ! peculi> lum9esc5ce :i* on cle> nights is diffus$ ov] ! sky z a consequ5ce ( electrical dis*>ges ( ?is /ray+ du/4 ,?is leads to ! "q :e!r ! magnific5t pol> lights1 :i* accord+ to mod]n views are also caus$ by electric dis*>ges 9 ! high] /rata ( ! atmosph]e1 are n produc$ by du/ :i* ! sun s5ds to u4 ,x w1 inde$1 be se5 t we c 9 ?is way expla9 q a numb] ( ! peculi>ities ( ^! my/]i\s ph5om5a :i* h always excit$ man's imag9ation4 ,we "k t meteorites & %oot+-/>s are r5d]$ inc&esc5t by ! resi/ance :i* !y enc\nt] 9 ! air at an av]age height ( #abj km4 7#ge miles71 sometimes ( #aej & #bjj km4 ,9 isolat$ cases meteorites are suppos$ to h become visible ev5 at /ill great] altitudes4 ,x w\ld result t !re mu/ be appreciable quantities ( air /ill at relatively high elevation1 & t ! atmosph]e _c be imp]ceptible at an altitude ( less ?an #ajj km41 z 0 =m]ly assum$4 ,bodies small] ?an ! meteorites z well z ! sol> du/ we h spok5 (--:i*1 ow+ to _! m9ut5ess & to ! /rong cool+ by heat radiation & conduction t !y und]go 9 pass+ ?r\gh ! atmosph]e1 c\ld nev] atta9 inc&esc5ce--w\ld be /opp$ at great] heights4 ,we w assume t !y are arre/$ at a mean height ( ab\t #djj km4 7#bej miles74 ,! masses ( du/ :i* are expell$ by ! sun are p>tly un*>g$1 p>tly *>g$ ) positive or negative electricity4 ,only ! latt] c be connect$ ) ! pol> lights2 ! =m] w\ld rema9 d>k & sl[ly s9k ?r\gh our atmosph]e to ! surface ( ! e>?4 ,!y =m ! s-call$ cosmical du/1 ( ^: great importance ,nord5skild 0 s firmly conv9c$4 ,he e/imat$ t ! ye>ly increase 9 ! weight ( ! e>? by ! addition ( ! meteorites 0 at lea/ t5 million tons1 or five hundr$ times m ?an we /at$ above 7page #ajh74 ,l ,locky] &1 9 m rec5t days1 ,*amb]l91 he believ$ t ! planets 7 l>gely built up ( meteorites4 ,! du/ rea*+ ! e>? f ! sun w\ld n1 7 x n electrically *>g$1 am\nt to m ?an #bjj tons 9 a ye>4 ,al?\gh ?is figure may be f> too l[1 yet ! supply ( matt] by ^! means is c]ta9ly v small 9 comp>ison ) ! #bj1jjj tons :i* ! e>? receives 9 ! %ape ( meteorites & %oot+-/>s4 ,b ow+ to its extremely m9ute di/ribution1 ! effect ( ?is du/ is v important1 & x may con/itute a mu* great] portion ( ! f9ely di/ribut$ cosmical du/ 9 ! highe/ /rata ( ! atmosph]e ?an ! du/ introduc$ by fall+ meteorites & %oot+-/>s4 ,t ^! p>ticles ex]t a noticeable influ5ce ^u t]re/rial conditions1 9 spite ( _! relatively insignificant mass1 is due to two causes4 ,!y are extremely m9ute & !re=e rema9 susp5d$ 9 our atmosph]e = long p]iods 7= m ?an a ye> 9 ! case ( ! ,krakatoa du/71 & !y are electrically *>g$4 ,9 ord] to und]/& _! action ^u ! e>?1 we w exam9e h[ ! t]re/rial conditions dep5d ^u ! position ( ! e>? ) reg>d to ! v>i\s active portions ( ! sun1 & ^u ! *ange ( ! sun itself 9 reg>d to its emission ( du/ p>ticles4 ,= ?is exam9ation we h to avail ourselves ( ext5sive /ati/ical data2 = only a long s]ies ( obs]vations c give u a cle> conception ( ! action ( sol> du/4 ,^! p>ticles )draw f ! sun gases :i* !y 7 able to cond5se on _! surface1 & :i* _h orig9ally be5 9 ! *romosph]e & 9 ! corona ( ! sun4 ,! mo/ important among ^! gases is hydrog52 next to x come helium & ! o!r noble gases :i* ,ramsay has discov]$ 9 ! atmosph]e1 9 :i* !y occur 9 v small quantities4 ,z reg>ds hydrog51 ,live+ & 7aft] him7 ,mit*ell h ma9ta9$ t x is n produc$ 9 ! t]re/rial atmosph]e4 ,occasionally x is c]ta9ly f\nd 9 volcanic gases4 ,?us hydrog5 escapes1 = in/ance1 f ! crat] ( ,kilauea1 on ,hawaii1 b x is burn$ at once 9 ! atmosph]e4 ,if hydrog5 7 pres5t 9 ! atmosph]e1 x w\ld gradually comb9e ) ! oxyg5 to wat] vapor2 & we h to assume1 !re=e1 t ! hydrog5 mu/ be introduc$ into our atmosph]e f ano!r s\rce--namely1 f ! sun4 ,mit*ell f9ds 9 ?is view a /rong support = ! op9ion t sol> du/ is always trickl+ d[n ?r\gh our atmosph]e4 ,! quantity ( sol> du/ :i* rea*es our atmosph]e w naturally v>y 9 proportion ) ! eruptive activity ( ! sun4 ,! quantity ( du/ 9 ! high] /rata influ5ces ! color ( ! light ( ! sun4 ,aft] ! eruption ( ! volcano ,rakata on ,krakatoa1 9 #ahhc1 & aga91 ?\gh to a less] degree1 aft] ! eruption ( ,mont ,pele on ,m>t9ique1 r$ sunsets & sunrises 7 obs]v$ all ov] ! globe4 ,at ! same "t1 ano!r ph5om5on 0 notic$ :i* c\ld be e/imat$ quantitatively4 ,! light ( ! sky is pol>iz$ ) ! exception ( ! light com+ f a few p>ticul> spots4 ,( ^! spots1 "o call$ ,arago's ,po9t is situat$ a little above ! antipode ( ! sun1 & ano!r1 ,bab9et's ,po9t1 is situat$ above ! sun4 ,if we det]m9e ! elevation ( ^! po9ts above ! horizon at sunset1 we f9d 9 accordance ) ! !oretical d$uction t ?is elevation is great] :5 ! high] /rata ( ! atmosph]e are *>g$ ) du/ 7z aft] ! eruption ( ,rakata7 ?an "u normal conditions4 ,bus*1 a ,g]man sci5ti/1 analyz$ ! mean elevation ( ^! po9ts 7/at$ 9 degrees ( arc7 at sunset1 & f\nd ! foll[+ peculi> numb]s3 #ahhf '#hg '#hh '#hi '#ij ,arago's ,po9t #bj4a #ai4g #ah4d #ag4h #ag4g ,bab9et's ,po9t#bc4i #ba4i #ag4i #ef4h #ae4d ,sun-spot ,numb]#ba4a #ai4a #f4g #f4a #f4e '#ia '#ib '#ic '#id '#ie ,mean ,arago's ,po9t #bj4f #ai4f #bj4b #bj4gah4h #ai4d ,bab9et's ,po9t#bc4c #ba4e #bd4b #bc4c #ai4j #bj4g ,sun-spot ,numb]#ce4f #gc4h #hd4i #gh4j #fc4i #dj4j ,!re is a di/9ct p>allelism 9 ^! s]ies ( figures4 ,almo/ simultane\sly ) ! sun-spot maximum ! height ( ! two s-call$ neutral po9ts above ! horizon atta9s its maximum at sunset1 & ! same applies to ! m9imum4 ,t ! ph5om5a 9 ! atmosph]e take place a little lat] ?an ! ph5om5a on ! sun :i* caus$ !m is p]haps only natural4 ,:5 ! air is ri* 9 du/1 or :5 x is /rongly ioniz$ by ka?ode rays1 conditions are favorable = ! =mation ( cl\ds4 ,?is c be obs]v$1 = in/ance1 ) auroral lights4 ,!y regul>ly give rise to a *>act]i/ic cl\d =mation1 s mu* s t ,adam ,pauls5 0 able to recognize pol> lights by ! aid ( ^! cl\ds 9 full daylight4 ,kle9 has compil$ a table on ! connection betwe5 ! frequ5cy ( ! high] cl\ds1 ! s-call$ cirrus cl\ds1 at ,cologne1 & ! numb] ( sun-spots dur+ ! p]iod #ahej-aijj4 ,he demon/rates t dur+ ?is half-c5tury1 :i* comprises m ?an f\r sun-spot p]iods1 ! sun-spot maxima fell 9 ! ye>s 9 :i* ! greate/ numb] ( cirrus cl\ds _h be5 obs]v$4 ,! m9ima ( ! two ph5om5a are likewise 9 agreem5t4 ,a simil>ly int5sifi$ =mation ( cl\ds seems also to occur on ,jupit] :5 sun-spots are frequ5t4 ,vogel /ates t ,jupit] at su* times %9es ) a :it] light1 :ile at sun-spot m9ima x appe>s ( a deep] r$4 ,! deep] we are able to peep into ! atmosph]e ( ,jupit]1 ! m r$di% x appe>s4 ,dur+ p]iods ( /rong sol> activity ! high] portions ( ,jupit]'s atmosph]e !re=e appe> to be cr[d$ ) cl\ds4 ,! dis*>ge ( ! *>g$ sol> du/ 9 our atmosph]e calls =? ! pol> lights4 ,! pol> lights occur1 z ! "n indicates1 mo/ frequ5tly 9 ! di/ricts ab\t ! poles ( ! e>?4 ,!y are1 h[ev]1 n actually m frequ5t ! ne>] we come to ! poles2 b !y atta9 a maximum ( frequ5cy 9 circles :i* enclose ! magnetic & ! geographical poles4 ,! nor!rn maximum belt passes1 via ,cape ,ts*eljusk91 nor? ( ,novaja ,semlja1 along ! nor?we/]n coa/ ( ,norway1 a few degrees to ! s\? ( ,icel& & ,gre5l&1 "r across ,hudson ,bay & ov] ! nor?we/]n ext5sion ( ,alaska4 ,:5 we g to ! s\? ( ?is belt1 ! auroras1 or boreal lights1 dim9i% m>k$ly4 ,!y are f\r times less frequ5t 9 ,ed9burgh1 & fifte5 times less frequ5t 9 ,london or ,new ,york1 ?an 9 ! ,orkney ,isl&s or ,labrador4 ,pauls5 divides ! auroras into two classes1 :i* behave q diff]5tly 9 sev]al respects4 ,! great difficulties :i* ! solution ( ! problems ( pol> lights has s f> (f]$ seem to a l>ge ext5t to be due to ! fact t all pol> lights 7 treat$ z be+ ( ! same k9d4 ,! pol> lights ( ! fir/ class d n display any /ream]s4 ,!y cov] a l>ge portion ( ! sky 9 a horizontal direction4 ,!y are v quiet1 & _! light is /rik+ly con/ant4 ,z a rule1 !y drift sl[ly t[>ds ! z5i?1 & !y d n give rise to any magnetic di/urbances4 ,^! pol> lights g5]ally h ! %ape ( an ar* ^: apex is situat$ 9 ! direction ( ! magnetic m]idian 7,fig4 #ch74 ,sometimes sev]al ar*es are gr\p$ "o above ano!r4 ,nord5skild obs]v$ ^! ar*es q regul>ly dur+ ! pol> night :5 he 0 w9t]+ ne> ,pitlekaj1 9 ! neighborhood ( ,b]+ ,s\nd4 ,adam ,pauls5 has (t5 se5 !m on ,icel& & ,gre5l&1 :i* are situat$ )9 ! maximum belt spok5 (1 :]e nor!rn lights are v common4 ,occasionally auroras are also se5 f>!r f ! poles1 z circul> ar*es ( a milky :ite1 :i* may be q high 9 ! heav5s4 ,sometimes we p]ceive 9 ! arctic regions t l>ge areas ( ! heav5s are cov]$ by a diffus$ light :i* might be/ be comp>$ to a lum9\s1 transp>5t cl\d2 ! d>k] portions 9 x probably appe> d>k by contra/4 ,?is ph5om5on 0 frequ5tly obs]v$ dur+ ! ,sw$i% exp$ition ( #ahhb-ahhc1 ne> ,cape ,?ords54 ,illu/ration3 ,fig4 #ch4--;,ar*-%ap$ auror borealis1 obs]v$ by ,nord5skild dur+ ! w9t]+ ( ! ,vega 9 ,b]+ ,/rait1 #ahgi ,masses ( light at s l[ a level t ! rocks beh9d !m are obscur$ h frequ5tly be5 obs]v$ to float 9 ! air1 especially 9 ! arctic di/ricts4 ,?us ,lem/rm saw an aurora on ! isl& ( ,spitzb]g5 9 front ( a wall ( rock only #cjj m4 7#ajjj ft47 9 height4 ,9 nor!rn ,f9l& he obs]v$ ! auroral l9e 9 ! light ( ! air 9 front ( a black clo? only a few metres di/ant4 ,adam ,pauls5 c\nts ^! ph5om5a also z pol> lights ( ! fir/ class1 & he reg>ds !m z phosphoresc5t cl\ds :i* h be5 c>ri$ d[n by convection curr5ts to an unusually l[ level ( our atmosph]e4 ,pol> lights ( ! second class are di/+ui%$ by ! *>act]i/ic auroral rays or /ream]s4 ,sometimes ^! /ream]s are q sep>at$ f "o ano!r 7see ,fig4 #ci72 z a rule !y melt into "o ano!r1 especially bel[1 s z to =m drap]ies :i* are s easily mov$ & un/eady t !y appe> to flutt] 9 ! w9d 7,fig4 #da47 ,! /ream]s run v approximately 9 ! direction ( ! incl9ation 7magnetic dip7 ne$le1 & :5 !y are fully develop$ ar\nd ! cele/ial dome _! po9t ( conv]g5ce is di/9ctly disc]nible 9 ! s-call$ corona 7,fig4 #dj74 ,:5 ! light is at its greate/ int5sity ! aurora is trav]s$ by num]\s waves ( light4 ,illu/ration3 ,fig4 #ci4--;,aurora borealis1 ) radial /ream]s ,! drap]ies are v ?94 ,pauls5 wat*$ !m sometimes drift+ ov] 8 head 9 ,gre5l&4 ,! drap]ies !n appe>$ =e%ort5$1 9 ! %ape ( /ri or ribbons ( light 9 convolutions4 ,^! pol> lights influ5ce ! magnetic ne$le4 ,:5 !y pass ! z5i? _! influ5ce *anges sign1 s t ! deviation ( ! magnetic ne$le *anges f ea/ to we/ :5 ! ribbon is mov+ f nor? to s\?4 ,pauls5 !re=e conclud$ t negative electricity 7ka?ode rays7 0 mov+ d[nw>d 9 ^! rays4 ,^! pol> lights correspond to viol5t displacem5ts ( negative electricity1 :ile pol> lights ( ! fir/ class appe> to consi/ ( a phosphoresc5t matt] :i* is n 9 /rong agitation4 ,! /ream]s may p5etrate d[n into r l[ atmosph]ic /rata1 at lea/ 9 di/ricts :i* are ne> ! maximum belt ( ! nor!rn lights4 ,?us ,p>ry obs]v$ at ,port ,b[5 an auroral /ream] 9 front ( a cliff only #bad m4 7#gjj ft47 9 height4 ,illu/ration3 ,fig4 #dj4--;,aurora ) corona1 obs]v$ by ,gyll5skild on ,spitzb]g51 #ahhc ,pol> lights ( ! fir/ ord] may pass into ^? ( ! second ord]1 & vice v]sa4 ,we frequ5tly see rays sudd5ly fla% out f ! ar* ( ! aurora1 mo/ly d[nw>d1 b1 :5 ! display is v int5se1 also upw>d4 ,on ! o!r h&1 ! viol5t agitation ( a 8drap]y light0 may cease1 & may give way to a diffus$1 /eady gl[ 9 ! sky4 ,! pol> light ( ! fir/ class is *iefly obs]v$ 9 ! arctic regions4 ,to x corresponds1 9 di/ricts f>!r remov$ f ! pole1 ! diffus$ light :i* appe>s to be spread uni=mly ov] ! heav5s & :i* gives ! auroral l9e4 ,illu/ration3 ,fig4 #da4--,pol>-light drap]ies1 obs]v$ 9 ,f9nm>k51 nor!rn ,norway ,! usually obs]v$ pol> lights 7speak+ n only ( ^? se5 on arctic exp$itions7 belong to ! second class1 :i* comprises also all ^? includ$ 9 ! subjo9$ /ati/ics1 ) ! exception ( ! auroral displays report$ f ,icel& & ,gre5l&4 ,:ile ! /ream] lights di/9ctly con=m to ! #aa4a ye>s' p]iod1 & become m frequ5t at times ( sun-spot maxima1 ?is is n ! case1 accord+ to ,tromholt1 ) ! auroras ( ,icel& & ,gre5l&4 ,_! frequ5cy1 on ! contr>y1 seems to be r indep5d5t ( ! sun-spot frequ5cy4 ,n r>ely auroral maxima correspond+ to sun-spot maxima are subdivid$ into two by a second>y m9imum4 ,?is ph5om5on is mo/ evid5t 9 ! pol> regions1 b x c also be trac$ 9 ! /ati/ics f ,sc&9avia & f o!r c\ntries4 ,bett] to und]/& ! nature ( auroras1 we w consid] ! sun's corona dur+ ! "t ( a m9imum ye>1 tak+ z an example ! ye> #aijj 7comp>e ,fig4 #cj74 ,! rays ( ! corona 9 ! neighborhood ( ! poles ( ! sun are lat]ally deflect$ by ! action ( ! magnetic l9es ( =ce ( ! sun4 ,! small1 negatively *>g$ p>ticles h evid5tly only a l[ velocity1 s t !y move q close to ! l9es ( =ce 9 ! neighborhood ( ! sol> poles & are conc5trat$ ne> ! equator4 ,!re ! l9es ( =ce are less cr[d$--t is to say1 ! magnetic =ces are weak]--& ! sol> du/ c !re=e be eject$ by ! radiation pressure & w accumulate to a l>ge disk exp&+ 9 ! equatorial plane4 ,to u ?is disk appe>s l two l>ge /reams ( rays :i* project 9 ! direction ( ! sol> equator4 ,"p ( ?is sol> du/ w come ne> ! e>? & be deflect$ by ! magnetic l9es ( =ce ( ! e>?2 x w h5ce be divid$ into two /reams :i* are direct$ t[>ds ! two t]re/rial magnetic poles4 ,^! poles are situat$ bel[ ! e>?'s cru/1 & !re=e n all ! rays w be conc5trat$ t[>ds ! app>5t position ( ! magnetic poles ^u ! surface ( ! e>?4 ,x is to be expect$ t ! negatively *>g$ p>ticles com+ f ! sun w *iefly drift t[>ds t di/rict :i* is situat$ some:at to ! s\? ( ! magnetic nor? pole1 :5 x is noon at ?is pole4 ,:5 x is midnight at ! magnetic pole1 mo/ ( ! negatively *>g$ p>ticles w be caught by ! l9es ( =ce be=e !y pass ! geographical nor? pole1 & ! maximum belt ( ! auroras w = ?is reason surr\nd ! magnetic & ! geographical poles1 z has already be5 po9t$ out 7comp>e page #abb74 ,! negatively *>g$ sol> du/ w ?us be conc5trat$ 9 two r+s above ! maximum belts ( ! pol> lights4 ,:]e ! du/ collides ) molecules ( ! air1 x w produce a phosphoresc5t gl[1 z if ^! molecules 7 hit by ! electrically *>g$ p>ticles ( radium4 ,?is phosphoresc5t gl[ rises 9 ! %ape ( a lum9\s ar* to a height ( ab\t #djj km4 7#bej miles7--accord+ to ,pauls5--& ! apex ( ?is ar* w 9 e "p seem to lie 9 ! direction :]e ! maximum belt is ne>e/ to ! /ation ( ! obs]v]4 ,t w fairly co9cide ) ! direction ( ! magnetic ne$le4 ,! sol> corona ( a sun-spot maximum ye> is ( a v diff]5t appe>ance 7,fig4 #ca74 ,! /ream]s radiate /raight f ! sun 9 almo/ all directions2 & if !re be "s privileg$ directions1 x w be ^? above ! sun-spot belts4 ,! velocity ( ! sol> du/ is evid5tly s great t ! /ream]s are no long] visibly deflect$ by ! magnetic l9es ( =ce ( ! sun4 ,nor is ?is *>g$ du/ influ5c$ to any noticeable degree by ! magnetic l9es ( =ce ( ! e>?4 ,x w 9 ! ma9 fall /raight d[n 9 t "p ( ! atmosph]e 9 :i* ! radiation is mo/ int5se3 ,z ^! 8h>d0 rays ( ! sun#h seem to issue f ! facul ( ! sun :i* are mo/ frequ5t 9 maximum sun-spot ye>s1 "s pol> lights w also be se5 9 di/ricts :i* are f> remov$ f ! maximum belt ( ! auroras1 especially :5 ! numb] ( sun-spots is l>ge4 ,! opposite relation holds = ! 8s(t0 /reams ( sol> du/ :i* fall ne> ! maximum belt ( ! pol> lights4 ,^! /reams occur mo/ frequ5tly ) l[ sun-spot frequ5cy1 z we "k f obs]vations ( ! sol> corona4 ,possibly !y are c>ri$ along by ! /ream ( h>d] rays 9 maximum ye>s4 ,! pol> lights correspond+ to ^! rays !re=e atta9 _! maximum ) few sun-spots4 ,h>d & s(t du/ /reams occur1 ( c\rse1 simultane\sly2 b ! =m] pr$om9ate 9 maximum sun-spot ye>s1 ! latt] 9 m9imum ye>s4 ,footnote #h3 ,! designations 8h>d0 & 8s(t0 /reams ( sol> du/ correspond to ! t]ms us$ ) reg>d to ka?ode rays4 ,! s(t rays h a small] velocity1 & are !re=e m /rongly deflect$ by ext]nal =ces1 z1 = in/ance1 magnetic =ces4 ,t ! p]iodicity ( ! pol> lights 9 regions )\t ! maximum belt foll[s v closely ! p]iodicity ( ! sun-spots 0 %[n by ,fritz z e>ly z #ahfc4 ,! l5g? ( ! p]iod v>ies betwe5 #g & #af ye>s1 ! av]age be+ #aa4a ye>s4 ,! ye>s ( maxima & m9ima = sun-spots & = nor!rn auroras are ! foll[+3 ,,maximum ,,ye>s ,sun-spots #agbh '#ci '#ej '#fb '#gj '#gh '#hh #ahjd '#af '#cj #ahcg '#dh '#fj '#ga '#hc '#ic #aije ,nor!rn lights #agcj '#da '#di '#fa '#gc '#gh '#hh #ahje '#ai '#cj #ahdj '#ej '#fb '#ga '#hb '#ic #aije ,,m9imum ,,ye>s ,sun-spots #agcd '#de '#ee '#fg '#gf '#he '#ih #ahaa '#bc '#cd #ahdd '#ef '#fg '#gh '#hi #aijj ,nor!rn lights #agce '#dd '#ee '#ff '#ge '#hc '#ii #ahaa '#bb '#cd #ahdd '#ef '#ff '#gh '#hi #aijj ,!re are1 9 addition1 z ,de ,mairan prov$ 9 8 classical memoir ( ! ye> #agdf1 long] p]iods common to bo? ! numb] ( sun-spots & ! numb] ( auroras4 ,accord+ to ,hansky1 ! l5g? ( ?is p]iod is #gb ye>s2 accord+ to ,s*u/]1 #cc ye>s4 ,v pron\nc$ maxima occurr$ at ! beg9n+ & ! end ( ! eighte5? c5tury1 ! la/ 9 ! ye> #aghh2 aft]w>ds auroras became v r>e 9 ! ye>s #ahjj-ahcj1 j z 9 ! middle ( ! eighte5? c5tury4 ,9 #ahej1 & p>ticul>ly 9 #ahga1 !re 7 /rong maxima2 !y h be5 abs5t s9ce !n4 ,! e/imates ( ! heights ( ! pol> lights v>y v consid]ably4 ,! height seems to be ! great]1 on ! :ole1 ! ne>] ! po9t ( obs]vation is to ! equator1 :i* w\ld well agree ) ! slight deflection ( ! ka?ode rays t[>ds ! surface ( ! e>? 9 regions :i* are f>!r remov$ f ! pole4 ,gyll5skild f\nd on ,spitzb]g5 a mean height ( #ee km42 ,bravais1 9 nor!rn ,norway1 #ajj to #bjj km42 ,de ,mairan1 9 c5tral ,europe1 #ijj km42 ,galle1 aga91 #cjj km4 ,9 ,gre5l&1 ,pauls5 obs]v$ nor!rn lights at v l[ levels4 ,9 ,icel& he fix$ ! apex ( ! nor!rn ar* :i* may be consid]$ z a po9t :]e ! *>g$ p>ticles f ! sun are dis*>g$ into ! air at ab\t #djj km4 ,n mu* reliance c be plac$ ^u ! e>li] det]m9ations2 b ! heights giv5 con=m approximately to ! ord] ( magnitude :i* we may d$uce f ! height at :i* ! sol> du/ w be /opp$ by ! t]re/rial atmosph]e4 ,! pol> lights possess1 fur!r1 a pron\nc$ ye>ly p]iodicity :i* is easily explicable by ! aid ( ! sol> du/ !ory4 ,we h se5 t sun-spots are r>ely obs]v$ ne> ! sol> equator1 & ! same applies to sol> facul4 ,!y rapidly increase 9 frequ5cy ) high] latitudes ( ! sun1 & _! maximum occurs at latitudes ( ab\t fifte5 degrees4 ,! equatorial plane ( ! sun is incl9$ by ab\t sev5 degrees t[>ds ! plane ( ! e>?'s orbit4 ,! e>? is 9 ! equatorial plane ( ! sun on ,decemb] #f? & ,june #d?1 & mo/ di/ant f x ?ree mon?s lat]4 ,we may1 !re=e1 expect t ! smalle/ numb] ( sol>-du/ p>ticles w fall on ! e>? :5 ! e>? is 9 ! equator ( ! sun--t is1 9 ,decemb] & ,june--& ! greate/ numb] 9 ,m>* & ,septemb]4 ,^! relations are some:at di/urb$ by ! twilight1 :i* int]f]es ) ! obs]vation ( auroras 9 ! bright summ] nights ( ! arctic region1 :ile ! d>k nights ( ! w9t] favor ! obs]vation ( ^! ph5om5a4 ,! di/ribution ( ! pol> lights ov] ! diff]5t seasons ( ! ye> w become cle> f ! subjo9$ table compil$ by ,ekholm & myself3 ,icel& & ,unit$ ,s\!rn ,sw$5 ,norway ,gre5l& ,/ates auror 7#ahhc-if7 7#ahfa-ie7 7#ahgb-ib7 7#ahga-ic7 7#ahef-id7 ,janu>y #ajef #bea #hjd #ajje #ef ,febru>y #aagc #cca #gcd #adee #abf ,m>* #acab #cce #fac #acif #ahc ,april #efh #ij #abh #agbd #adh ,may #agj #f #a #abgj #ed ,june #aj #j #j #ajfa #dj ,july #ed #j #j #abcc #ce ,augu/ #aia #ah #dj #abaj #ge ,septemb] #ajee #bji #dee #agce #abj ,octob] #aaad #cec #gaf #afcj #aib ,novemb] #ajgg #cbf #haa #abdj #aab ,decemb] #idj #bfj #hfc #iab #ha ,av]age numb] #gbg #aha #dcj #acbb #ajb ,9 zones :]e ! diff]5ce betwe5 ! l5g?s ( day & night ( ! diff]5t seasons is n v great1 z 9 ! ,unit$ ,/ates1 & 9 di/ricts 9 :i* ! s\!rn light is obs]v$ 7ab\t latitude #dj ,s471 ! *ief m9imum falls 9 w9t]3 on ! nor!rn hemisph]e1 9 ,decemb]2 on ! s\!rn hemisph]e1 9 ,june or ,july4 ,a less pron\nc$ m9imum occurr+ 9 ! summ]4 ,twice 9 ! c\rse ( ! ye> ! e>? passes ?r\gh ! plane ( ! sol> equator4 ,dur+ ^! p]iods a m9imum ( sol> du/ trickles d[n ^u ! e>?1 & t p]iod is *>act]iz$ by a l>g] numb] ( pol> lights :i* is di/+ui%$ by a high] elevation ( ! sun above ! horizon4 ,we may expect ?is2 = mo/ sol> du/ w fall ^u t portion ( ! e>? ov] :i* ! sun is highe/ at noon4 ,! two maxima ( ,m>* or ,april & ( ,septemb] or ,octob]1 :5 ! e>? is at its greate/ di/ance f ! plane ( ! sol> equator1 are /rongly m>k$ 9 all ! s]ies1 except 9 ^? = ! pol> di/ricts ,icel& & ,gre5l&4 ,!re ! auroral frequ5cy is solely dep5d5t ^u ! int5sity ( ! twilight1 s t we f9d a s+le maximum 9 ,decemb] & ! correspond+ m9imum 9 ,june4 ,m rec5t /ati/ics 7#ahia-aijc7 indicate1 h[ev]1 a m9imum 9 ,decemb]4 ,= ! same reason ! summ] m9imum 9 c\ntries ( high latitudes1 l ,sw$5 & ,norway1 is v mu* acc5tuat$4 ,simil> reasons r5d] x difficult = mo/ localities to indicate ! daily p]iodicity ( ! pol> lights4 ,mo/ ( ! sol> du/ falls ab\t noon2 & mo/ pol> lights %\ld !re=e be c\nt$ a few h\rs aft] noon1 j z ! highe/ temp]ature ( ! day is rea*$ a little aft] noon4 ,on acc\nt ( ! int5se sunlight1 h[ev]1 ?is maximum c only be e/abli%$ 9 ! w9try night ( ! pol> regions1 & ev5 !re only :5 a correction has be5 made = ! di/urb+ effect ( ! twilight4 ,9 ?is way ,gyll5skild f\nd a nor!rn-light maximum at #b4dj ,p4,m4 = ,cape ,?ords51 on ,spitzb]g51 ! correspond+ m9imum be+ at #g4dj ,a4,m4 ,9 o!r localities we c only asc]ta9 t ! pol> lights are m int5se & m frequ5t be=e ?an aft] midnight4 ,9 c5tral ,europe ! maximum occurs at ab\t #i ,p4,m42 9 ,sw$5 & ,norway 79 latitude #fj ,n471 half an h\r or an h\r lat]4 ,a few o!r p]iods1 approximately ( ! l5g? ( a mon?1 h be5 sugge/$ ) reg>d to pol> lights4 ,a p]iod la/+ #be4ic days pr$om9ates 9 ! s\!rn lights1 :]e ! maximum exce$s ! av]age by #dd p] c5t4 ,= ! nor!rn lights 9 ,norway ! correspond+ excess p]c5tage is #bc2 = ,sw$51 only #aa4i ,footnote #i3 ,! reason is t 9 ! s\!rn di/rict only v few1 & *iefly ! mo/ int5se1 auroras are record$4 ,if we obs]ve v assidu\sly 9 a l>ge c\ntry1 & conduct ! obs]vations at diff]5t spots1 we %all f9d pol> light almo/ e night4 ,?is consid]ation p>tly wipes out ! j-m5tion$ diff]5ces4 ,! same p]iod ( ne>ly tw5ty-six days _h already be5 po9t$ out = a long s]ies ( o!r especially magnetic ph5om5a :i*1 z we %all see1 are v closely connect$ ) auroras1 & x _h also be5 f\nd 9 ! frequ5cy ( ?und]-/orms & 9 ! v>iations ( ! b>omet]4 ,?is p]iodicity has (t5 be5 ?\ght to be connect$ ) ! axial rotation ( ! sun4 ,! ,au/rian sci5ti/ ,horn/e9 has ev5 gone s f> z to propose t ! l5g? ( ?is p]iod %\ld be c>efully det]m9$1 8because x w\ld give a m accurate value = ! rotation ( ! sun ?an ! direct det]m9ations40 ,we "k n[ t ! l5g? ( ! sol> revolution is diff]5t = diff]5t sol> altitudes1 a circum/ance ) :i* obs]vations ( sun-spot movem5ts at diff]5t latitudes _h already made ,c>r+ton & ,spr] famili>1 b :i* 0 n safely e/abli%$ be=e ,dunr's spectroscopical det]m9ation ( ! movem5t ( ! sol> photosph]e4 ,dunr f\nd ! foll[+ sid]eal revolutions = diff]5t latitudes ( ! sun to :i* ! subjo9$ synodical revolution w\ld correspond4 7,by sid]eal revolution ( a po9t on ! sun we und]/& ! "t :i* elapses betwe5 ! two mom5ts :5 a c]ta9 /> passes1 on two consecutive occasions1 ?r\gh ! m]idian plane ( ! po9t--t is to say1 ?r\gh a plane laid ?r\gh ! poles ( ! sun & ! po9t 9 "q4 ,! synodical revolution is det]m9$ by ! passage ( ! e>? ?r\gh ?is m]idian4 ,on acc\nt ( ! prop] motion ( ! e>? ! synodical p]iod is long] ?an ! sid]eal p]iod47 ,latitude on ! sun 7degrees7 #j #ae #cj #de #fj #ge ,sid]eal revolution 7days7 #be4d #bf4d #bg4f #cj4j #cc4i #ch4e ,synodical revolution 7days7 #bg4c #bh4e #bi4i #cb4g #cg4d #dc4j ,t ! p]iods ( rotation ( ! sol> photosph]e1 &1 9 a simil> way1 ! p]iods ( ! spots1 ! facul1 & ! prom95ces1 %\ld become s consid]ably long] ) increas+ latitudes is "o ( ! mo/ my/]i\s problems ( ! physics ( ! sun4 ,some?+ simil> applies to ! cl\ds ( ,jupit]1 b ! diff]5ce 9 t case is mu* small]--only ab\t "o p] c5t4 ,! cl\ds ( our atmosph]e behave q diff]5tly1 a fact :i* is expla9$ by our atmosph]ic circulation4#aj ,footnote #aj3 ,! v highe/ /rata ( our atmosph]e 7at levels ( f #bj to #hj km41 #ae to #ej miles7 may p]haps =m an exception4 ,! lum9\s cl\ds :i* 7 obs]v$ 9 ! ye>s #ahhc-ahib at ,b]l9 7aft] ! eruption ( ,krakatoa71 & :i* 7 float+ at a v high level1 %[$ a drift ) reg>d to ! surface ( ! e>? opposite to ! drift ( ! cirrus cl\ds1 :i* are direct$ ea/w>d4 ,9 our case1 ( c\rse1 ! position ( ! sun ) reg>d to ! e>?--t is to say1 ! synodical p]iod--c alone be ( importance4 ,we recognize t ! p]iod ( #be4ic days does n at all agree ) any p]iod ( ! sol> photosph]e4 ,! sol> equatorial zone diff]s lea/1 & x w\ld be appropriate to reckon ) ?is p]iod1 s9ce ! e>? nev] moves v f> f ! plane ( ! sol> equator1 & returns to t plane1 at any rate1 twice 9 ! c\rse ( a ye>4 ,b !re is ano!r peculi>ity4 ,! high] a po9t is situat$ 9 ! atmosph]e ( ! sun1 ! %ort] is its p]iod4 ,?us ! synodical p]iod ( ! facul ne> ! equator is on an av]age #bf4jf1 ! p]iod ( ! spots #bf4hb1 ( ! photosph]e #bg4c days4 ,facul situat$ at high] levels revolve /ill m rapidly1 & we are ?us driv5 to ! conclusion t ! p]iod to :i* we h allud$ agrees ) ! p]iod ( ! facul situat$ at high] levels 9 ! equatorial zone ( ! sun1 & is probably dep5d5t ^u !m4 ,t w\ld con=m to our ideas conc]n+ ! physics ( ! sun4 ,= ! facul are produc$ 9 ! asc5d+ curr5ts ( gas & at r l[] levels ?an ! sph]ules :i* are expell$ by ! radiation pressure4 ,?is radiation pressure is /ronge/ j 9 ! neighborhood ( ! facul4 ,= ! same reason ! repulsion ( ! sol> du/ becomes p>ticul>ly p[]ful :5 ! facul are /rongly develop$--t is to say1 j 9 ! "t ( pron\nc$ eruptive activity ( ! sun :i* is *>act]iz$ by _m sun-spots4 ,we mu/ ?us imag9e t ! radiation ( ! sun w be /rong] 9 times ( /rong eruptive activity ?an dur+ ! days ( l[ sun-spot frequ5cies4 ,direct obs]vations ( ! int5sity ( ! sol> radiation :i* h be5 made by ,saveljeff 9 ,kieff confirm ?is assumption4 ,x mu/ be po9t$ out1 h[ev]1 t ano!r ph5om5on inve/igat$ by ,kpp5 seems to contradict ?is conclusion4 ,kpp5 asc]ta9$ t 9 our tropics ! temp]ature 0 by #j4cb ,c5t4 7ne>ly #j4f ,f47 l[] dur+ sun-spot maxima ?an ! av]age1 & t five ye>s lat]1 a ye> be=e ! sun-spot m9imum1 x rea*$ its maximum value ( #j4da ,c5t4 7#j4g ,f47 above ! av]age4 ,a simil> peculi>ity c be trac$ to o!r zones1 b on acc\nt ( ! less /eady climates x is mu* less m>k$ !re ?an 9 ! tropics4 ,a ,fr5* physici/1 ,nordmann1 has fully confirm$ ! obs]vations ( ,kpp54 ,on ! o!r h&1 ,v1 an ,am]ican a/ronom]1 has f\nd t ! temp]ature 9 v dry 7des]t7 di/ricts ( ! tropics 7ne> ,port ,d>w91 #ab #bh ,s41 & ne> ,alice ,spr+s1 #bc #ch ,s41 bo? 9 ,au/ralia7 is high] at sun-spot maxima ?an at m9ima2 b ,v 0 9 ?is rese>* guid$ m]ely by ! records ( maximum & m9imum !rmomet]s4 ,f ,v's inve/igation x w\ld appe> t ! sol> radiation is really m int5se ) l>g] sun-spot numb]s4#aa ,?is1 x mu/ be rem>k$1 is only noticeable 9 exce$+ly dry di/ricts 9 :i* !re is no cl\d =mation wor? m5tion+4 ,9 o!r di/ricts ! cl\d =mation :i* accompanies sun-spot maxima int]f]es ) ! simplicity ( ! ph5om5a4 ,! cool+ effect ( ! cl\ds seems 9 ^! cases by f> to surpass ! direct heat+ effect ( ! sol> rays1 & 9 ?is mann] ,kpp5's conclusion w\ld become explicable4 ,if we c\ld obs]ve ! temp]atures ( ! atmosph]ic /rata above ! cl\ds1 _! v>iation w\ld no d\bt be 9 ! same degree z t 9 ! des]t4 ,footnote #aa3 ,accord+ to ,mem]y 7,bull4 ,soc4 ,a/r41 ,m>* #g1 #aijf1 p4 #afh7 an in/antane\s rise ( temp]ature is obs]v$ imm$iately :5 a sun-spot is fir/ se51 & ! temp]ature s9ks aga9 :5 ! sun-spot disappe>s4 ,f9ally1 we h to note ano!r p]iod 9 ! ph5om5a ( ! pol> lights--! s-call$ tropical mon?1 ^: l5g? is #bg4c days4 ,! nature ( ?is p]iod is little und]/ood4 ,x is possibly connect$ ) ! electric *>ge ( ! moon4 ,! peculi>ity ( ?is p]iod is t x acts 9 an opposite way 9 ! nor!rn & s\!rn hemisph]es4 ,:5 ! moon is above ! horizon1 x seems to prev5t ! =mation ( pol> lights2 b = ?is case ! difficulties ( obs]vation caus$ by ! moonlight mu/1 ( c\rse1 be tak5 into consid]ation4 ,illu/ration3 ,fig4 #db4--;,curve ( magnetic decl9ation at ,kew1 ne> ,london1 on ,novemb] #ae & #af1 #aije4 ,! viol5t di/urbance ( ,novemb] #ae1 #i ,p4,m41 corresponds to ! maximum int5sity ( ! aurora4 ,comp>e ! foll[+ figure ,celsius & ,hiort] obs]v$ 9 #agda t ! pol> lights ex]cise an influ5ce on ! magnetic ne$le4 ,f ?is circum/ance we h drawn ! conclusion t ! pol> lights are 9 "s way due to electric dis*>ges :i* act ^u ! magnetic ne$le4 ,^! magnetic effects1 ! di/urbances ( ! o!rwise /eady position ( ! magnetic ne$le1 are n influ5c$ by ! light ( ! sun & moon1 & c !re=e be /udi$ to great] advantage ?an auroras4 ,we h already po9t$ out t x is only ! aurora ( ! radial1 /ream] type :i* ex]ts ?is magnetic influ5ce 7comp>e ,figs4 #db & #dc74 ,illu/ration3 ,fig4 #dc4--;,curve ( horizontal int5sity at ,kew on ,novemb] #ae & #af1 #aije4 ,on ,novemb] #ae a magnific5t aurora 0 obs]v$ 9 ,galicia1 ,g]many1 ,france1 ,norway1 ,engl&1 ,irel&1 & ,nova ,scotia1 ) a maximum at #i ,p4,m4 ,! pol> light 0 unusually brilliant z e>ly z #f ,p4,m4 ,^! magnetic v>iations %[ exactly ! same p]iods z ! nor!rn lights & ! sun-spots4 ,z reg>ds1 fir/1 ! long p]iod ( #aa4a ye>s1 our obs]vations prove t ! s-call$ magnetic di/urbances ( ! position ( ! magnetic ne$le fai?fully reflect ! v>iations 9 ! sun-spots4 ,?is connection 0 discov]$ 9 #aheb by ,sab9e 9 ,engl&1 by ,wolf 9 ,switz]l&1 & by ,gauti] 9 ,france4 ,ev5 ! m irregul> diurnal v>iations 9 ! magnetic elem5ts are subject$ to a sol> p]iod4 ,! magnetic ne$le po9ts 9 our di/ricts ) its nor? end t[>ds ! nor?--n exactly1 ?\gh1 be+ deflect$ t[>ds ! we/4 ,?is we/]n deviation or decl9ation is greate/ soon aft] noon1 ab\t "o o'clock1 & ?is diurnal *ange is great] 9 summ] ?an 9 w9t]1 & ! fluctuation ( ! position ( ! magnetic ne$le great] 9 daytime ?an at night-"t4 ,x is1 !re=e1 manife/ t we h to deal ) "s sol> effect4 ,?is becomes /ill m di/9ct :5 we /udy ! *ange ) ref]5ce to ! daily v>iation 9 ! numb] ( sun-spots4 ,9 ! subjo9$ table ! v>iation 9 ! decl9ation has be5 compil$ = ,prague = ! ye>s #ahef to #ahhi4 ,only ye>s ) maxima & m9ima ( sun-spots & ( magnetic v>iations h be5 notic$ 9 ?is table3 #ahef #ahfj #ahfg #ahga #ahgi #ahhd #ahhi ,sun-spot numb] #d4c #ie4g #g4c #aci4a #c4d #fc4g #f4c ,,daily ,,v>iations ,,9 ,,decl9ation #ahef #ahei #ahfg #ahga #ahgh #ahhc #ahhi ,obs]v$ #e4ih #aj4cf #f4ie #aa4dc #e4fe #h4cd #e4ii ,calculat$ #f4jh #aj4bj #f4bb #ab4ae #f4jd #h4gf #f4ag ,we see t ! maxima & m9ima ye>s ( ! two ph5om5a v ne>ly co9cide4 ,! accord is s evid5t t we may calculate ! diurnal v>iation z proportional to ! increase 9 ! numb] ( sun-spots4 ,?is is %[n by ! two la/ l9es ( ! table4 ,! ye>ly v>iation is aga9 exactly ! same z t ( pol> lights1 z ! foll[+ table indicates1 9 :i* ! di/urbances ( magnetic decl9ation1 horizontal int5sity1 & v]tical int5sity are compil$ = ,toronto1 ,canada2 = comp>ison ! means ( ^! ?ree magnitudes are add$ = ,gre5wi*4 ,! unit ( ?is table is ! av]age annual v>iation3 ,,toronto ,jan4 ,feb4 ,m>4 ,april ,may ,june ,july ,decl9ation #j4eg #j4hd #a4aa #a4db #j4ih #j4ec #j4id ,horizontal #j4ef #j4id #j4id #a4ej #j4ij #j4cf #j4fa ,v]tical #j4eg #j4gd #a4jh #a4di #a4ab #j4ej #j4ga ,aug4 ,sept4 ,oct4 ,nov4 ,dec4 ,decl9ation #a4af #a4fb #a4ca #j4gh #j4gf ,horizontal #j4ge #a4ga #a4dh #j4ih #j4eh ,v]tical #a4jh #a4fa #a4bi #j4ge #j4fa ,,gre5wi* ,jan4 ,feb4 ,m>4 ,april ,may ,june ,july ,means #j4ic #a4bc #a4bb #a4ji #j4ha #j4ga #j4ha ,aug4 ,sept4 ,oct4 ,nov4 ,dec4 ,means #j4ij #a4ae #a4ah #a4jb #j4hc ,! daily v>iation ( ! di/urbances has be5 analyz$ by ,van ,bemmel5 = ! p]iod #ahhb-ahic & = ! obs]vatory ( ,batavia1 on ,java4 ,! maximum occurs !re ab\t #a ,p4,m41 & is ab\t #a4hf times z great z ! av]age value = ! day4 ,! m9imum ( #j4dh occurs at #aa ,p4,m4 ,betwe5 #h ,p4,m4 & #c ,a4,m4 ! di/urbances are almo/ z r>e z ab\t #aa o'clock at night4 ,! v>iation is greate/ ) t decl9ation :i* has its maximum ( #c4bf at #ab ,m41 & its m9imum ( #j4ad at #aa ,p4,m4 ,! p]iod ( almo/ #bf days fir/ inve/igat$ by ,horn/e9 has also be5 ref\nd 9 ! magnetic v>iations & di/urbances by ,br\n1 ,liznr1 & ,c4 ,a4 ,mll]4 ,x mu/ be add$1 h[ev]1 t ,s*u/] does n consid] ^! data z 9 any way conclusive4 ,! moon has also a slight influ5ce ^u ! magnetic ne$le1 z ,kreil prov$ z e>ly z #ahda4 ,! effect is 9 a diff]5t sign 9 ! nor!rn & s\!rn hemisph]es1 & may be lik5$ to a tidal ph5om5on4 ,! ultra-violet rays ( ! sun are /rongly absorb$ by ! atmosph]e1 & !y cause an ionization ( ! molecules ( ! air4 ,?is ionization is1 on ! :ole1 m m>k$ at high] altitudes4 ,! asc5d+ air curr5ts c>ry ) !m wat] vapor :i* is cond5s$ on ! ions1 p>ticul>ly on ! negative ions4 ,9 ?is way mo/ cl\ds become negatively *>g$2 ?is int]e/+ fact--i4e41 t !y are m frequ5tly *>g$ ) negative ?an ) positive electricity--0 fir/ prov$ by ,frankl9 9 8 kite exp]im5ts4 ,:5 ! ra9-drops h fall51 ! air above rema9s positively *>g$2 ?is has be5 obs]v$ dur+ balloon asc5sions4 ,! cl\ds :i* are =m$ at high levels are mo/ /rongly *>g$2 = ?is reason ?und]-/orms ov] l& occur mo/ly 9 ! summ]-"t4 ,! ?und]-/orms also %[ ! #bf-;day p]iod1 z ,bezold has prov$ = s\!rn ,g]many1 & ,ekholm & myself h %[n = ,sw$54 ,a va/ am\nt ( mat]ial conc]n+ ^! que/ions & magnetic ph5om5a 9 p>ticul> has be5 collect$ by ! v>i\s meteorological obs]vatories & is await+ analysis4 ,al?\gh "s obs]v]s l ,sidgreaves "q ! correlation ( sun-spots & pol> lights or magnetic di/urbances1 because /rong spots h be5 se5 on ! disk ( ! sun )\t any magnetic di/urbances hav+ be5 notic$1 yet ! view pr$om9ates t ! magnetic di/urbances are caus$ by sun-spots :5 ! sun-spots cross ! c5tral m]idian ( ! sun :i* is opposite ! e>?4 ,?us ,maund] obs]v$ a magnetic /orm & a nor!rn light succe$+ ! passage ( a l>ge sun-spot ?r\gh ! c5tral sol> m]idian on ! #h? to ! #aj? ( ,septemb]1 #ahih4 ,! magnetic effect atta9$ its maximum ab\t tw5ty-"o h\rs aft] ! passage ?r\gh ! m]idian4 ,simil>ly ,ricc e/abli%$ 9 t5 in/ances1 9 :i* exact det]m9ation 0 possible1 a "t int]val ( #de4e h\rs on an av]age betwe5 ! m]idian passage ( a spot & ! maximum magnetic effect4 ,ricc also submitt$ to an analysis ! data :i* ,ellis _h collect$ & :i* ,maund] _h inve/igat$4 ,he f\nd = ^! in/ances1 on an av]age1 almo/ exactly ! same numb]s1 ! "t int]val be+ #db4e h\rs4 ,t w\ld correspond to a mean velocity ( ! sol> du/ ( f #iaj to #ihj km4 p] second4 ,on ! o!r h&1 we h no difficulty at all 9 calculat+ ! "t :i* a sph]ule ( a diamet] ( #j4jjjaf mm4 7^? p>ticles travel fa/e/7 & ( ! specific gravity ( wat] w\ld ne$ 9 ord] to rea* ! e>?1 "u ! influ5ce ( sol> gravitation & ( a me*anical radiation pressure #b4e times z l>ge f ! outside ( ! sun4 ,! "t f\nd1 #ef4a h\rs1 corresponds to a mean velocity ( #gdj km4 p] second4 ,9 ord] t ! sol> du/ may move ) ! velocity calculat$ by ,ricc1 its specific gravity %\ld be less ?an #a--viz41 #j4ff & #j4eg4 ,?is value looks by no means improbable1 :5 we assume t ! sph]ules consi/ ( hydroc>bons saturat$ ) hydrog51 helium1 & o!r noble gases4 ,we %\ld also arrive at l>g] velocities = ! sol> du/1 z has already be5 po9t$ out ) reg>d to ! tails ( comets1 :5 we presume t ! p>ticles consi/ ( felt$ m>gu]ites ( c>bon or silicates1 or ( iron--mat]ials :i* we reg>d z ! ma9 con/itu5ts ( meteorites4 ,x %\ld1 p]haps1 be m5tion$ t ! mo/ int5se spectrum l9e ( ! pol> lights has be5 f\nd to be *>act]i/ic ( ! noble gas krypton4 ,z ?is gas is f\nd only 9 v small quantities 9 our atmosph]e1 x does n appe> improbable t x has be5 c>ri$ to u toge!r ) ! sol> du/1 & t its spectrum becomes p]ceptible dur+ ! dis*>ge ph5om5a4 ,! o!r spectrum l9es ( ! pol> lights belong to ! spectra ( nitrog51 argon1 & ( ! o!r noble gases4 ,! volumes ( noble gases :i* are br\ght into our t]re/rial atmosph]e 9 ?is mann] w\ld 9 any case be exce$+ly small4 ,! electrical ph5om5a ( our t]re/rial atmosph]e indirectly possess consid]able importance = organic life &1 consequ5tly1 = human be+s4 ,by ! electrical dis*>ges "p ( ! nitrog5 is made to comb9e ) ! oxyg5 & hydrog5 7lib]at$ by ! electric decomposition ( wat] vapor7 ( our air1 & x ?us =ms ! ammonia comp\nds1 z well z ! nitrates & nitrites1 :i* are s ess5tial to vegetable gr[?4 ,! ammonia comp\nds :i* play a mo/ important "p 9 ! temp]ate zones appe> especially to be =m$ by ! s-call$ sil5t dis*>ges :i* we connect ) auroras4 ,! oxyg5 comp\nds ( nitrog51 on ! o!r h&1 seem to be *iefly ! products ( ! viol5t ?und]-/orms ( ! tropics4 ,! ra9s c>ry ^! comp\nds d[n into ! soil1 :]e !y f]tilize ! plants4 ,! supply ( nitrog5 ?us fix$ am\nts 9 ! c\rse ( a ye> to ab\t #a4be gramme p] squ>e metre 9 ,europe1 & to almo/ f\rfold t figure 9 ! tropics4 ,if we accept ?ree grammes z ! av]age numb] = ! :ole firm l& ( ! e>?1 t w\ld mean #c tons p] squ>e kilometre1 & ab\t #djj million tons p] ye> = ! :ole firm l& ( #acf million squ>e kilometres4 ,a v small portion ( ?is fix$ nitrog51 possibly "o-tw5tie?1 falls on cultivat$ soil2 a l>g] portion w help to /imulate plant gr[? 9 ! =e/s & on ! /eppes4 ,we may m5tion1 = comp>ison1 t ! nitrog5 conta9$ 9 ! saltpetre :i* ! m9es ( ,*ili yield to u has ris5 f #ej1jjj tons 9 #ahhj to #abj1jjj tons 9 #ahij1 to #baj1jjj tons 9 #aijj1 & to #bfj1jjj tons 9 #aije4 ,! nitrog5 produc$ 9 ! %ape ( ammonium salts 7sulphate7 by ! gas-works ( ,europe am\nts to ab\t "o-qu>t] ( ! la/-m5tion$ figure4 ,to ?is figure we h1 ( c\rse1 to add ! production ( coal-gas ammonia 9 ! ,unit$ ,/ates & else:]e4 ,yet ev5 all[+ = ?is item1 we %all f9d t ! artificial supply ( comb9$ nitrog5 on ! e>? does n repres5t m ?an ab\t "o-?\s&? ( ! natural supply4 ,z ! nitrog5 cont5ts ( ! air may be e/imat$ at #cihj billion tons1 we recognize t only "o "p 9 ?ree millions ( ! nitrog5 ( ! atmosph]e is e ye> fix$ by electric dis*>ges1 presum+ t ! nitrog5 supply to ! sea is z great p] squ>e kilometre z to ! l&4 ,! nitrog5 ?us fix$ b5efits ! plants ( ! sea & ( ! l&1 & passes back into ! atmosph]e or into ! wat] dur+ ! life ( ! plants or dur+ _! decay4 ,wat] absorbs "s nitrog51 & equilibrium betwe5 ! nitrog5 cont5ts ( ! atmosph]e & ( ! sea is ?us ma9ta9$4 ,h5ce we ne$ n fe> any notewor?y depletion ( ! nitrog5 cont5ts ( ! air4 ,?is conclusion is 9 accord ) ! fact t no notable accumulation ( fix$ nitrog5 appe>s to h tak5 place 9 ! solid & liquid con/itu5ts ( ! e>?4 ,! read] may rememb] 7comp>e page #eg7 t dur+ ! annual cycle ( vegetation n less ?an "o-fiftie? ( ! atmosph]ic cont5ts 9 ! c>bon dioxide is absorb$4 ,s9ce oxyg5 is =m$ f ?is c>bon dioxide1 & s9ce ! air conta9s ab\t sev5 hundr$ times z _m p>ts p] volume ( oxyg5 z ( c>bon dioxide1 ! ex*ange ( atmosph]ic oxyg5 is ab\t "o "p 9 ?irty-five ?\s&4 ,9 o!r words1 ! oxyg5 ( ! air p>ticipates ab\t "o hundr$ times m en]getically 9 ! processes ( vegetation ?an ! nitrog51 & ?is is 9 accordance ) ! g5]al high *emical activity ( oxyg54 ,be=e we close ?is *apt] we w briefly ref] to ! peculi> ph5om5on kn[n z ! ,zodiacal ,light1 :i* c be se5 9 ! tropics almo/ any cle> night = a few h\rs aft] or be=e sunset or sunrise4 ,9 our latitudes ! light is r>ely visible1 & is be/ se5 ab\t ! p]iods ( ! v]nal & autumnal equ9oxes4 ,! ph5om5on is g5]ally describ$ z a lum9\s cone ^: basis lies on ! horizon1 & ^: middle l9e co9cides ) ! zodiac4 ,h5ce ! "n4 ,accord+ to ,wright & ,liais1 its spectrum is cont9u\s4 ,x is /at$ t ! ,zodiacal ,light is z /rong 9 ! tropics z t ( ! ,milky ,way4 ,illu/ration3 ,fig4 #dd4--,zodiacal ,light 9 ! tropics ,!re c be no d\bt t ?is gl[ is due to du/ p>ticles illum9at$ by ! sun4 ,x has !re=e be5 assum$ t ?is du/ is float+ ab\t ! sun 9 a r+1 & t x repres5ts ! re/ ( t primeval nebula out ( :i* ! sol> sy/em has be5 cond5s$1 accord+ to ! !ory ( ,kant & ,laplace 7comp>e ,*apt] ,,vii474 ,sometimes a fairly lum9\s b& seems to %oot out f ! apex ( ! cone ( ! ,zodiacal ,light & to cross ! sky 9 ! plane ( ! ecliptic4 ,9 t "p ( ! sky :i* is j opposite ! sun ?is b& exp&s to a l>g]1 diffus$1 n well-def9$ spot ( light cov]+ ab\t #ab ( arc 9 latitude & #ij 9 longitude4 ,?is lum9esc5ce is call$ ! c\nt]-gl[ 7,geg5s*e971 & 0 fir/ describ$ by ,pez5as 9 #aghj4 ,! mo/ probable view conc]n+ ! nature ( ?is c\nt]-gl[ is t x is caus$ by small p>ticles ( meteorites or du/ :i* fall t[>ds ! sun4 ,l ! position ( ! corona ( ! aurora1 ! position ( ?is c\nt]-gl[ seems to be an effect ( p]spective2 ! orbits ( ! little p>ticles are direct$ t[>ds ! sun1 & !y !re=e appe> to radiate f a po9t opposite to x4 ,we "k v little ab\t ?is ph5om5on4 ,ev5 ! position ( ! ,zodiacal ,light along ! zodiac :i* has giv5 rise to its "n has be5 que/ion$1 & x w\ld appe> f rec5t inve/igations t ! gl[ is situat$ 9 ! plane ( ! sol> equator4 ,h[ev] t may be1 ! view is v g5]ally held t ! gl[ is due to p>ticles :i* come f ! sun or ent] into x4 ,we h already adduc$ argum5ts to prove t ! mass ( sol> du/ _c be unimportant2 ?is du/ may !re=e be ! cause ( ! ph5om5on :i* we h j be5 discuss+4 ,,vi ,,end ,,( ,,! ,,sun--,,orig9 ,,( ,,nebul ,we h se5 t ! sun is dissipat+ & wa/+ almo/ inconceivable am\nts ( heat e ye>3 #c4h4 #ajcc gramme-calories1 correspond+ to #b gramme-calories = ea* gramme ( its mass4 ,we h also obta9$ an idea z to h[ ! enorm\s /orage ( heat en]gy 9 ! sun may endure ?is loss = ages4 ,f9ally1 h[ev]1 ! "t mu/ come :5 ! sun w cool d[n & :5 x w cov] itself ) a solid cru/1 z ! e>? & ! o!r planets--s f>1 probably1 9 a gase\s /ate--h done long s9ce or w d be=e long4 ,no liv+ be+ w be able to wat* ?is ext9ction ( ! sun despair+ly f "o ( ! w&]+ planets2 =1 9 spite ( all our inv5tions1 all life w long be=e h ceas$ on ! satellites ( ! sun = want ( heat & light4 ,! fur!r developm5t ( ! cold sun w recall ! actual progress ( our e>?1 except 9 s f> z ! sun w h no life-sp5d+1 c5tral s\rce ( light & heat ne> x4 ,9 ! beg9n+ ! ?91 solid cru/ w aga9 & aga9 be bur/ by gases1 & /reams ( lava w ru% out f ! int]ior ( ! sun4 ,aft] a :ile ^! p[]ful dis*>ges w /op1 ! lava w freeze1 & ! fragm5ts w close up m firmly ?an be=e4 ,only on "s ( ! old fissures volcanoes w rise & all[ ! gases to escape f ! int]ior--wat] vapor &1 to a less ext5t1 c>bonic acid1 lib]at$ by ! cool+4 ,!n wat] w be cond5s$4 ,oceans w flood ! sun1 & = a %ort p]iod x w resemble ! e>? 9 its pres5t condition1 ?\gh ) ! "o important diff]5ce4 ,! ext9ct sun1 unlike our e>?1 w n receive life-giv+ heat f ! outside1 except+ ! small am\nt ( radiation f univ]sal space & ! heat g5]at$ by ! fall ( meteorites4 ,! temp]ature fall w !re=e be rapid1 & ! vani%+ cl\ds ( ! att5uat$ atmosph]e w n long *eck radiation4 ,! ocean w become cov]$ ) a cru/ ( ice4 ,!n ! c>bonic acid w comm5ce to cond5se1 & w be precipitat$ z a light sn[ 9 ! sol> atmosph]e4 ,f9ally1 at a temp]ature ( ab\t -#bjj ,c5t41 ! gases ( ! atmosph]e w be cond5s$1 & new oceans1 n[ pr9cipally ( nitrog51 w be produc$4 ,let ! temp]ature s9k ano!r #bj1 & ! en]gy ( ! inru%+ meteorites w j suffice to balance a fur!r loss ( heat by radiation4 ,! sol> atmosph]e w !n consi/ ess5tially ( helium & hydrog5--! two gases :i* are mo/ difficult to cond5se--& ( "s nitrog54 ,9 ?is /age ! heat loss ( ! sun w be almo/ imp]ceptible4 ,ow+ to ! l[ !rmal conductive p[] ( ! e>?'s cru/1 !re escapes ?r\gh ea* squ>e mile ( ?is cru/ sc>cely "o-?\s&-million? "p ( ! heat :i* ! sun is radiat+ f an equal area ( its surface4 ,9 future days1 :5 ! sol> cru/ w h atta9$ a ?ickness ( #fj km4 7#dj miles71 its loss ( heat w be dim9i%$ to ! same degree4 ,! temp]ature on ! surface ( ! sun may !n /ill be "s #ej or #fj above absolute z]o1 & volcanic eruptions w raise ! temp]ature only = %ort p]iods & ov] small areas4 ,yet 9 ! int]ior ! temp]ature w /ill be at ne>ly ! same actual int5sity1 some?+ l sev]al million degrees1 & ! comp\nds ( inf9ite explosive en]gy w be /or$ up !re z today4 ,l an imm5se dynamite magaz9e1 ! d>k sun w float ab\t 9 univ]sal space )\t wa/+ mu* ( its en]gy 9 ! c\rse ( billions ( ye>s4 ,immutable1 l a spore1 x w reta9 its imm5se /ore ( =ce until x is awak5$ by ext]nal =ces into a new span ( life simil> to ! old life4 ,a sl[ %r9kage ( ! surface1 due to ! progressive loss ( heat ( ! core & to ! consequ5t contraction1 w 9 ! mean:ile h cov]$ ! sun ) ! wr9kles ( old age4 ,let u suppose t ! cru/s ( ! sun & ! e>? h ! same !rmal conductivity--namely1 t ( granite4 ,accord+ to ,homn1 a slab ( granite "o c5timetre 9 ?ickness1 ^: two surfaces are at a temp]ature diff]5ce ( #a ,c5t41 w p]mit #j4ehb calorie to pass p] m9ute p] squ>e c5timetre ( surface4 ,by analogy1 ! e>?'s cru/1 ) an increase ( temp]ature ( #cj p] kilometre1 z we p5etrate inw>d1 w\ld all[ #a4ge 4#aj-d calorie to pass p] m9ute & p] squ>e c5timetre 7?is is #a_/cehj ( ! mean heat supply ( ! e>?1 #j4fbe calorie p] m9ute p] squ>e c5timetre72 :ile ! sun1 ) a cru/ ( ! same ?ickness z ! e>?1 b ) a diamet] #ajh4f times l>g]1 w\ld lose #c4c times m heat p] m9ute ?an ! e>? receives f x at ! pres5t "t4 ,at pres5t ! sun loses #bbfj million times m heat ?an ! e>? receives2 consequ5tly1 ! loss ( heat w\ld be r$uc$ to #a_/fhf1jjj1jjj ( ! pres5t am\nt4 ,if ! ?ickness ( ! sol> cru/ am\nt$ to #a_/adj ( ! sol> radius--t is to say1 to ! same fraction t ! ?ickness ( ! e>?'s cru/ repres5ts ( ! t]re/rial radius--! sun w\ld 9 #gd1ejj million ye>s n lose any m heat ?an x does n[ 9 a s+le ye>4 ,?is numb] has to be dim9i%$1 on acc\nt ( ! cold] surface :i* ! sun w\ld h by t "t1 to ab\t #fj1jjj million ye>s4 ,consid]+ t ! mean temp]ature ( ! sun may be z high z #e million degrees ,celsius1 ! cool+ d[n to ! freez+-po9t ( wat] might occupy #aej1jjj billion ye>s1 assum+ t its mean specific heat is z great z t ( wat]4 ,dur+ ?is "t ! cru/ ( ! sun w\ld increase 9 ?ickness & ! cool+ w\ld1 ( c\rse1 proce$ at a decreas+ rate4 ,9 any case1 ! total loss ( en]gy dur+ a p]iod ( a ?\s& billion ye>s c\ld1 "u ^! circum/ances1 only con/itute a v small fraction ( ! total /or$ en]gy4 ,:5 an ext9ct /> moves =w>d ?r\gh inf9ite spaces ( "t1 x w ultimately meet ano!r lum9\s or likewise ext9ct />4 ,! probability ( su* a collision is proportional to ! angle "u :i* ! /> appe>s--:i*1 ?\gh v small1 is n ( z]o magnitude--& to ! velocity ( ! sun4 ,! probability is increas$ by ! deflection :i* ^! cele/ial bodies w und]go 9 _! orbits on approa*+ ea* o!r4 ,our ne>e/ neighbors 9 ! /ell> univ]se are s f> remov$ f u t light1 ! light ( our sun1 requires1 on an av]age1 p]haps t5 ye>s to rea* !m4 ,9 ord] t ! sun1 ) its actual dim5sions & its actual velocity 9 space--#bj km4 7#ac miles7 p] second--%\ld collide ) ano!r /> ( simil> k9d1 we %\ld require some?+ l a hundr$ ?\s& billion ye>s4 ,suppose t !re are a hundr$ times m ext9ct ?an lum9\s />s--an assumption :i* is n unju/ifiable--! probable int]val up to ! next collision may be some?+ l a ?\s& billion ye>s4 ,! "t dur+ :i* ! sun w\ld be lum9\s w\ld repres5t p]haps "o-hundr$? ( ?is--t is to say1 t5 billion ye>s4 ,?is conclusion does n look unreasonable4 ,= life has only be5 exi/+ on ! e>? = ab\t a ?\s& million ye>s1 & ?is age repres5ts only a small fraction ( ! "t dur+ :i* ! sun has emitt$ light & w cont9ue to emit light4 ,! probability ( a collision betwe5 ! sun & a nebula is1 ( c\rse1 mu* great]2 = ! nebul ext5d ov] v l>ge spaces4 ,9 su* a case1 h[ev]1 we ne$ n appreh5d any m s]i\s consequ5ces ?an result :5 a comet is pass+ ?r\gh ! corona ( ! sun4 ,ow+ to ! v small am\nt ( matt] 9 ! corona1 we h n p]ceiv$ any notewor?y effects 9 ^! in/ances4 ,nev]!less1 ! entrance ( ! sun into a nebula w\ld increase ! *ance ( a collision ) ano!r sun2 = we %all see bel[ t d>k & lum9\s cele/ial bodies appe> to be aggregat$ 9 ! nebul4 ,f "t to "t we see new />s sudd5ly fla% up 9 ! sky1 rapidly decrease 9 spl5dor aga91 to become ext+ui%$ or1 at any rate1 to dw9dle d[n to fa9t visibility once m4 ,! mo/ rem>kable ( ^! exce$+ly int]e/+ ev5ts occurr$ 9 ,febru>y1 #aija1 :5 a /> ( ! fir/ magnitude appe>$ 9 ! con/ellation ( ,p]seus4 ,?is /> 0 discov]$ by ,&]son1 a ,scot*man1 on ! morn+ ( ,febru>y #bb1 #aija4 ,x 0 !n a /> ( ! ?ird magnitude4#ab ,on a photograph :i* _h be5 tak5 only tw5ty-eight h\rs previ\s to ! discov]y ( ?is />1 ! /> 0 n visible at all1 al?\gh ! plate m>k$ />s d[n to ! twelf? magnitude4 ,! light int5sity ( ?is new /> w\ld h5ce appe> to h increas$ m ?an five-?\s&-fold )9 t %ort space ( "t4 ,on ,febru>y #bc;d ! new /> surpass$ all o!r />s except ,sirius 9 int5sity4 ,by ,febru>y #be? x 0 ( ! fir/ magnitude1 by ,febru>y #bg? ( ! second1 by ,m>* #f? ( ! ?ird1 & by ,m>* #ah? ( ! f\r? magnitude4 ,!n its brightness began to fluctuate p]iodically up to ,june #bb;d1 ) a p]iod fir/ ( ?ree1 !n ( five days1 :ile ! av]age light int5sity decreas$4 ,by ,june #bc;d x 0 ( ! six? magnitude4 ,! light int5sity dim9i%$ !n m uni=mly4 ,by ,octob]1 #aija1 x 0 a /> ( ! sev5? magnitude2 by ,febru>y1 #aijb1 ( ! eigh? magnitude2 by ,july1 #aijb1 ( ! n9? magnitude2 by ,decemb]1 #aijb1 ( ! t5? magnitude2 & s9ce !n x has gradually dw9dl$ to ! twelf? magnitude4 ,:5 ?is /> 0 at its highe/ int5sity x %one ) a blui%-:ite light4 ,! %ade !n *ang$ into yell[1 & by ! beg9n+ ( ,m>*1 #aija1 into r$di%4 ,dur+ its p]iodical fluctuations ! hue 0 :iti% yell[ at its maximum & r$di% at its m9imum int5sity4 ,s9ce !n ! color has gradually pass$ into pure :ite4 ,footnote #ab3 ,/>s are classifi$ 9 magnitude1 ! ord] be+ su* t ! mo/ lum9\s />s h ! l[e/ numb]s4 ,a /> ( ! fir/ magnitude is #b4eb times bright] ?an a /> ( ! second magnitude2 ?is1 aga91 #b4eb times bright] ?an a /> ( ! ?ird magnitude1 & s on4 ,all ?is f ! po9t ( view ( an obs]v] on ! e>?4 ,! spectrum ( ?is /> %[s ! greate/ simil>ity to t ( ! new /> 9 ! con/ellation ,auriga 7,nova ,aurig7 ( ! ye> #ahib 7,fig4 #de74 ,illu/ration3 ,fig4 #de4--,spectrum ( ,nova ,aurig1 #ahib ,on ! :ole1 x is *>act]i/ic ( new />s t ! spectrum l9es appe> d\ble--d>k on ! violet & bright on ! r$ side4 ,9 ! spectrum ( ,nova ,aurig ?is peculi>ity is1 among o!rs1 /rik+ 9 ! ?ree hydrog5 l9es ,c1 ,f1 & ,h1 9 ! sodium l9e1 9 ! nebula l9es1 & also 9 ! magnesium l9e4 ,9 ! spectrum ( ,nova ,p]sei ! displacem5t ( ! hydrog5 l9es t[>ds ! violet is s great t1 accord+ to ,doppl]'s pr9ciple1#ac ! hydrog5 gas :i* absorb$ ! light mu/ h be5 mov+ t[>ds u ) a velocity ( #gjj or m kilometres 7#dej miles7 p] second4 ,"s calcium l9es %[ a simil> displacem5t1 :i* is less noticeable 9 ! case ( ! o!r metals4 ,?is w\ld appe> to indicate t relatively cold masses ( gas are issu+ f ! />s & /ream+ ) enorm\s velocities t[>ds ! e>?4 ,! lum9\s p>ts ( ! />s 7 ei!r at a /&-/ill or !y 7 mov+ away f u4 ,! simple/ explanation ( ^! ph5om5a w\ld be t a /> :5 fla%+ up by virtue ( its high temp]ature & high pressure %[s enhanc$ 7wid5$7 spectral l9es1 ^: violet portion is absorb$ by ! /rongly cool$ masses ( gas :i* are mov+ t[>ds u & are cool$ by _! own /rong expansion4 ,^! gases /ream1 ( c\rse1 9 all directions f ! />1 b we only become aw>e ( ^? gases :i* absorb ! light ( ! />s--t is to say1 ^? situat$ betwe5 ! /> & ! e>?1 & /ream+ 9 our direction4 ,footnote #ac3 ,:51 /&+ on a /ation plat=m1 we wat* an express tra9 ru%+ ?r\gh ! /ation1 ! pit* ( ! eng9e :i/le seems to become high] z long z ! tra9 is approa*+ u1 & deep] aga9 :5 ! tra9 is mov+ away f u4 ,! pit* ( a note dep5ds ^u ! numb] ( oscillations :i* our e> receives p] second4 ,n[1 :5 ! tra9 is fa/ approa*+ u1 m vibrations are s5t into our e> ?an :5 ! tra9 is at a /&-/ill1 & ! pit*1 !re=e1 appe>s to become high]4 ,! same reason+ holds = light waves1 ( :i* ,doppl]1 ( ,prague 7,bohemia71 0 9 fact ?9k+ :5 fir/ ann\nc+ 8 pr9ciple 9 #ahdb4 ,! wave-l5g? ( a p>ticul> color ( ! spectrum is fix$ ) ! aid ( "s ,fraunh(] l9e *>act]i/ic ( a c]ta9 metal4 ,if we comp>e ! spectrum ( a /> & ! spectrum ( a gl[+ metal1 photograph$ on ! same plate1 ! /ell> l9es w appe> %ift$ t[>ds ! violet end 7violet light is produc$ by ne>ly twice z _m vibrations ( ! e!r p] second z r$ light7 :5 ! /> is mov+ t[>ds u 9 ! l9e ( sight4 ,?is pr9ciple has successfully be5 appli$ by ,hugg9s1 ,h4 ,c4 ,vogel1 & o!rs1 = det]m9+ ! motion ( a /> 9 our l9e ( sight4 ,:5 a /> is revolv+ ab\t its own axis1 ! equatorial belt w seem to come ne>] to u 7or to rec$e f u71 :ile ! pol> regions w seem to be at a /&-/ill2 ! l9es w !n appe> oblique 7n v]tical74 ,9 ?is way ,keel] prov$ t ! r+s ( ,saturn consi/s ( sw>ms ( meteorites mov+ at diff]5t velocities 9 ! diff]5t r+s4--,h4 ,b4 ,gradually ! light ( ! metallic l9es & ( ! cont9u\s spectrum on :i* !y 7 sup]pos$ began to fade1 fir/ 9 ! violet1 :ile ! hydrog5 l9es & nebul> l9es /ill rema9$ di/9ct2 l o!r new />s1 ?is /> %[$1 aft] a :ile1 ! nebul> spectrum4 ,?is int]e/+ fact 0 fir/ notic$ by ,h4 ,c4 ,vogel 9 ! new /> 9 ! ,swan 7,nova ,cygni1 #ahgf74 ,! /> ,p 9 ! ,swan1 :i* fla%$ up 9 ! ye> #afjj1 /ill (f]s u a spectrum :i* indicates ! emission ( hydrog5 gas4 ,x is n impossible t ?is 8new0 /> has n yet rea*$ its equilibrium1 & is /ill cont9u+ to emit cold /reams ( gases4 ,insignificant quantities ( gas suffice = ! =mation ( an absorption spectrum2 ?us ! emission ( gas might cont9ue = long p]iods )\t exhau/+ ! supply4 ,we h already m5tion$ 7page #aaf7 ! peculi> cl\ds ( light :i* 7 obs]v$ ar\nd ,nova ,p]sei4 ,two annul> cl\ds mov$ away f ?is /> ) velocities ( #a4d & #b4h seconds ( arc p] day betwe5 ,m>* #bi1 #aija1 & ,febru>y1 #aijb4 ,if we calculate backw>d f ^! dates ! "t :i* mu/ h elaps$ s9ce ^? gases left ! />1 we arrive at ! date ( ! week--,febru>y #h to #af1 #aija--;9 satisfactory agreem5t ) ! p]iod ( greate/ lum9osity ( ! /> ( ,febru>y #bc;d4 ,x w\ld1 !re=e1 appe> t ^! emanations came f ! /> & 7 eject$ by ! radiation pressure4 ,_! light did n m>k any noticeable pol>ization1 & c\ld n be reflect$ light = ?is reason4 ,we may suppose t ! du/ p>ticles dis*>g$ _! electric *>ges1 & t ! gases became !reby lum9\s4 ,9 ?is case we 7 evid5tly witnesses ( ! gr& f9ale ( ! indep5d5t exi/5ce ( a cele/ial body by collision ) "s o!r body ( equal k9d4 ,! two collid+ bodies 7 bo? d>k1 or !y emitt$ s little light t _! comb9$ light int5sities did n equal t ( a /> ( ! twelf? magnitude4 ,z1 n[1 _! spl5dor aft] ! collision 0 great] ?an t ( a /> ( ! fir/ magnitude1 al?\gh _! di/ance has be5 e/imat$ to be at lea/ #abj light ye>s1#ad _! radiation int5sity mu/ h exce$$ t ( ! sun sev]al ?\s& times4 ,"u ^! circum/ances ! me*anical radiation pressure mu/ also h be5 _m times m p[]ful ?an on ! surface ( ! sun1 & ! masses ( du/ :i* 7 eject$ by ! new /> mu/ h possess$ a velocity v mu* great] ?an t ( sol> du/4 ,yet ?is velocity mu/ h be5 small] ?an t ( light1 :i*1 inde$1 ! effect ( ! radiation pressure c nev] equal4 ,footnote #ad3 ,"o light ye> corresponds to #i4e billion kilometres1 & x is ! di/ance :i* ! light trav]ses 9 ! c\rse ( a ye>4 ,illu/ration3 ,fig4 #df4--;,diagram indicat+ ! consequ5ces ( a collision betwe5 two ext9ct suns1 ,a & ,b #8mov+' 9 ! direction ( ! /raight arr[s4 ,a rapid rotation 9 ! direction ( ! curv$ arr[s results1 & two p[]ful /ream]s are eject$ by ,a ,b1 ! explosive sub/ances f ! deep] /rata ( ,a & ,b be+ br\ght up to ! surface by ! collision ,x is n difficult to picture to ourselves ! enorm\s viol5ce ) :i* ?is 8collision0 mu/ h tak5 place4 ,a /range body--= in/ance1 a meteorite--:i* ru%es f ! inf9ite univ]se into ! sun has at its collision a velocity ( #fjj km4 7#djj miles7 p] second1 & ! velocity ( ! two collid+ suns mu/ h be5 ( approximately t ord]4 ,! impact w 9 g5]al be oblique1 &1 al?\gh "p ( ! en]gy w ( c\rse be trans=m$ into heat1 ! re/ ( ! k9etic en]gy mu/ h produc$ a rotational velocity ( hundr$s ( kilometres p] second4 ,by comp>ison ) ?is numb] ! actual circumf]5tial spe$ ( ! sun1 ab\t #b km4 7#a-a_/d miles7 p] second on ! equator1 w\ld vani% altoge!r2 & ! diff]5ce is /ill m /rik+ = ! e>?1 ) its #j4dfe km4 p] second at ! equator4 ,we %all1 !re=e1 n commit an error ( any consequ5ce if we presume ! two bodies to h be5 practically devoid ( circumf]5tial spe$s be=e _! collision4 ,at ! collision1 matt] w h be5 eject$ f bo? ^! cele/ial bodies at "r angles to ! relative directions ( _! motion 9 two p[]ful torr5ts1 :i* w\ld be situat$ 9 ! plane 9 :i* ! two bodies 7 approa*+ ea* o!r 7comp>e ,fig4 #df74 ,! rotational spe$ ( ! d\ble />1 :i* w be dim9i%$ by ?is ejection ( matt]1 w h contribut$ to increase ! en]gy ( ejection4 ,we rememb]1 n[1 t :5 matt] is br\ght up f ! int]ior to ! surface ( ! sun x w behave l an explosive ( enorm\s p[]4 ,! eject$ gases w be hurl$ 9 t]rific flight ab\t ! rapidly revolv+ c5tral portions4 ,we obta9 an idea 7?\gh a v imp]fect "o7 ( ^! features :5 we look at a revolv+ p9:eel 9 a fireworks display4 ,two p9:eels h be5 atta*$ to ! ends ( a diamet] & bel* =? fire 9 radial l9es4 ,! f>!r remov$ f ! :eel1 ! small] w be ! actual velocity & also ! angul> velocity ( ^! torr5ts ( fire4 ,simil>ly ) ! />4 ,! /reams are rapidly cool$1 ow+ to ! rapid expansion ( ! gas4 ,!y w also conta9 f9e du/1 l>gely consi/+ ( c>bon1 probably1 :i* _h be5 b\nd by ! explosive mat]ials4 ,! cl\ds ( f9e du/ w obscure ! new /> m & m1 & w gradually *ange its :ite brilliancy into yell[ & r$di%1 because ! f9e du/ weak5s blue-&-gre5 rays m ?an x does yell[-&-r$ rays4 ,at fir/ ! cl\ds 7 s ne> to ! /> t !y possess$ a high angul> velocity ( _! own2 !y !n appe>$ to surr\nd ! /> completely4 ,b aft] ,m>* #bb1 #aija1 ! out] p>ticles ( ! /reams atta9$ great] di/ances & assum$ long] p]iods ( revolution 7six days72 ! /> !n became m obscur$ :5 ! extreme du/ cl\ds ( ! /reams cov]+ x happ5$ to get betwe5 u & ! />4 ,z ! /reams ( p>ticles 7 mov+ f>!r away1 _! rotational p]iods increas$ gradually to t5 days4 ,! />1 !re=e1 became p]iodical ) a sl[ly gr[+ l5g? ( p]iod1 & its gl[ turn$ m r$di% at its m9imum ?an at its maximum ( int5sity4 ,at ! same "t1 ! absorptive p[] ( ! m>g9al p>ticles decreas$1 p>tly ow+ to _! increas+ expansion1 p>tly because ! du/ 0 sl[ly aggregat+ to co>s] p>ticles2 possibly1 also1 because ! f9e/ p>ticles 7 be+ driv5 away by ! radiation pressure4 ,! sift+ influ5ce :i* ! du/ ex]cis$ ^u ! light1 & ow+ to :i* ! r$-&-yell[ rays 7 m readily transmitt$ ?an ! blue-&-gre51 gradually became impair$2 h5ce ! color ( ! light turn$ m gray1 & aft] a c]ta9 "t ! /> appe>$ once m ( a :iti% hue4 ,?is :ite color indicates t ! /> mu/ /ill h a v high temp]ature4 ,by ! cont9u$ ejection ( du/-*>g$ masses ( gas1 probably ) gradually decreas+ viol5ce1 ! light int5sity ( ! /> mu/ sl[ly dim9i% 7z se5 f ! e>?7 & ! di/ribution ( ! lay]s ( du/ ar\nd ! lum9\s core w m & m become uni=m4 ,h[ viol5t ! explosion mu/ h be51 we recognize f ! obs]vation t ! fir/ eject$ masses ( hydrog5 ru%$ out ) an app>5t velocity ( at lea/ #gjj km4 p] second4 ,?is velocity is ( ! same ord] z t ( ! mo/ rem>kable prom95ces ( ! sun4 ,illu/ration3 ,fig4 #dg4--,spiral nebula 9 ! ,canes ,v5atici4 ,messi] #ea4 ,tak5 at ! ,y]kes ,obs]vatory on ,june #c1 #aijb4 ,scale1 #a mm4 #ac4b sec4 ( arc ,x w be admitt$ t ^! argum5ts pres5t u ) a fai?ful simile ev5 ( ! details ( ! obs]v$ c\rse ( ev5ts1 & x is !re=e highly probable t our view is 9 ! ma9 correct4 ,b :at has mean:ile become ( ! new />8 ,spectrum analysis tells u t x has be5 conv]t$ into a /ell> nebula l o!r new />s4 ,! cont9u\s light ( ! c5tral body has m & m be5 weak5$ by ! surr\nd+ masses ( du/4 ,by ! radiation pressure ^! masses are driv5 t[>ds ! out] p>ticles ( ! surr\nd+ gase\s envelope consi/+ pr9cipally ( hydrog51 helium1 & 8nebul> matt]40 ,!re ! du/ dis*>ges its negative electricity1 & ?us calls =? a lum9esc5ce :i* equals t ( ! nebul4 ,illu/ration3 ,fig4 #dh4--,spiral nebula 9 ! ,triangle4 ,messi] #cc4 ,tak5 at ! ,y]kes ,obs]vatory on ,septemb] #d & #f1 #aijb4 ,scale1 #a mm4 #cj4g sec4 ( arc ,we h to consid] next t ow+ to ! incr$ibly rapid rotation1 ! c5tral ma9 mass ( ! two />s w1 9 its out] portions1 be expos$ to c5trifugal =ces ( extraord9>y int5sity1 & w !re=e become flatt5$ out to a l>ge revolv+ disk4#ae ,z ! pressure 9 ! out] portions w be relatively small1 ! d5sity ( ! gases w likewise be dim9i%$ !re4 ,! en]getic expansion &1 m /ill1 ! great heat radiation w l[] ! temp]ature at a rapid rate4 ,we h ?us to deal ) a c5tral body ^: inn] portion w possess a high d5sity1 & :i* w resemble ! mass ( ! sun1 :ile ! out] portion w be att5uat$ & nebul>4 ,di/ribut$ ab\t ! c5tral body we %all f9d ! re/ ( ! two /reams ( gases :i* 7 eject$ imm$iately aft] ! viol5t collision betwe5 ! two cele/ial bodies4 ,a n inconsid]able portion ( ! matt] ( ^! spirally arrang$ out] p>ts w probably travel f>!r away into inf9ite space1 f9ally to jo9 "s o!r cele/ial body or to =m p>ts ( ! great irregul> spots ( nebul> matt] :i* are collect$ ar\nd ! /> clu/]s4 ,ano!r portion1 n able to leave ! c5tral body1 w rema9 9 circul> movem5t ab\t x4 ,9 consequ5ce ( ?is circul> movem5t1 :i* w be extremely sl[1 ! outl9es ( ! two spirals w gradually become oblit]at$1 & ! spirals w !mselves m & m assume ! %ape ( nebul> r+s ab\t ! c5tral mass4 ,footnote #ae3 ,a4 ,ritt] has calculat$ t :5 two suns ( equal size collide ) "o ano!r f an inf9ite di/ance1 ! en]gy ( ! collision is n m ?an suffici5t to enl>ge ! volume ( ! suns to f\r times ! previ\s am\nt4 ,! l>ge/ portion ( ! mass w !re=e probably rema9 9 ! c5tre1 & x w only be masses ( light gases :i* w be eject$4 ,illu/ration3 ,fig4 #di4--,! great nebula 9 ,&rom$a4 ,tak5 at ! ,y]kes ,obs]vatory on ,septemb] #ah1 #aija4 ,scale1 #a mm4 #ed4f sec4 ( arc ,illu/ration3 ,fig4 #ej4--,r+-%ap$ nebula 9 ,lyra4 ,tak5 at ! ,y]kes ,obs]vatory ,?is spiral =m 7,figs4 #dg & #dh7 ( ! out] portions ( ! nebul has = a long "t excit$ ! greate/ att5tion4 ,9 almo/ all ! inve/igat$ in/ances x has be5 obs]v$ t two spiral bran*es are coil+ ab\t ! c5tral body4 ,?is w\ld indicate t ! matt] is 9 a revolv+ movem5t ab\t ! c5tral axis ( ! spiral1 & t x has /ream$ away f ! axis 9 two opposite directions4 ,sometimes ! matt] appe>s arrang$ z 9 a coil2 ( ?is type ! great nebula ( ,&rom$a is ! be/-kn[n example 7,fig4 #di74 ,a clos] inspection ( ?is nebula ) m p[]ful in/rum5ts indicates1 h[ev]1 t x is also spiral & t x appe>s coil$1 because we are look+ at x f ! side4 ,! late fam\s ,am]ican a/ronom] ,keel]1 :o has /udi$ ^! nebul ) great] success ?an any "o else1 has catalogu$ a great _m ( !m 9 all ! divisions ( ! heav5s :i* 7 accessible to 8 in/rum5ts1 & he has f\nd t ^! =mations are pr$om9at+ly ( a spiral nature4 ,illu/ration3 ,fig4 #ea4--;,c5tral portion ( ! great nebula 9 ,orion4 ,tak5 at ! ,y]kes ,obs]vatory4 ,scale1 #a mm4 #ab sec4 ( arc ,"s nebul1 l ! s-call$ planet>y nebul1 (f] r ! appe>ance ( lum9\s sph]es4 ,we may assume 9 ^! cases t ! explosions 7 less viol5t1 & t ! spirals1 !re=e1 are situat$ s closely toge!r t !y seem to m]ge into "o ano!r4 ,possibly ! inequalities 9 _! developm5t h become equaliz$ 9 ! c\rse ( "t4 ,a few nebul are r+-%ap$1 z ! well-kn[n nebula ( ,lyra 7see ,fig4 #ej74 ,^! r+s may1 aga91 h be5 =m$ out ( spiral nebul1 & ! spirals may h gradually be5 oblit]at$ by rotation1 :ile ! c5tral nebul\s matt] may h be5 conc5trat$ on ! planets travell+ r\nd ! c5tral />4 ,s*aeb]le1 an em95t ,am]ican a/ronom]1 has discov]$ traces ( spiral %ape also 9 ! ,lyra nebula4 ,ano!r k9d ( nebula is ! ord9>y nebula ( va/ ext5sion & irregul> %ape1 evid5tly =m$ out ( mo/ extremely att5uat$ matt]2 well-kn[n *>act]i/ic examples are f\nd 9 ,orion1 ab\t ! ,pleiades1 & 9 ! ,swan 7,figs4 #ea1 #eb1 & #ec74 ,9 ^! nebul portions ( a spiral /ructure h likewise (t5 be5 disc]n$4 ,illu/ration3 ,fig4 #eb4--,nebul> /ri 9 ! />s ( ! ,pleiades4 ,tak5 at ! ,y]kes ,obs]vatory on ,octob] #ai1 #aija4 ,scale1 #a mm4 #db4b sec4 ( arc ,we h said t ! collision betwe5 two cele/ial bodies w\ld result 9 ! =mation ( a spiral ) two w+s4 ,if ! impact is su* t ! two c5tres ( ! cele/ial bodies move /raight t[>ds ea* o!r1 a disk w arise1 & n a spiral2 or if "o /> is mu* small] ?an ! o!r1 possibly a cone1 because ! gases w uni=mly be spread 9 all directions ab\t ! l9e ( impact4 ,a p]fectly c5tral impact is obvi\sly v r>e2 b !re may be cases :i* approa* ?is limit+ condition m or less1 especially :5 ! relative velocity ( ! two bodies is small4 ,by sl[ diffusion a feebly develop$ spiral may also be conv]t$ into a rotat+ disklike /ructure4 ,! ext5sion ( ^! nebul> /ructures w dep5d ^u ! ratio betwe5 ! mass ( ! sy/em & ! velocity ( ejection ( ! gases4 ,if1 = example1 two ext9ct suns ( ne>ly equal dim5sions & mass1 l our sun1 %\ld collide1 "s gas masses w\ld travel into inf9ite space1 be+ hurl$ out ) a velocity ( m ?an #ijj km4 7#eej miles7 p] second2 :ile o!r p>ticles1 mov+ at a sl[] rate1 w\ld rema9 9 ! neighborhood ( ! c5tral body4 ,! ne>] to t body1 ! small] 0 _! velocity4 ,f _! position !y might fall back into ! c5tral body1 to be re9corporat$ 9 x1 if two circum/ances did n prev5t ?is4 ,! "o circum/ance is ! enorm\s radiation pressure ( ! gl[+ c5tral mass4 ,t pressure keeps masses ( du/ p>ticles float+1 :i* by friction w c>ry ! surr\nd+ masses ( gas ) !m4 ,ow+ to ! absorption ( ! radiation by ! du/ p>ticles1 only ! f9] p>ticles w be support$ f>!r outside1 & at ! extreme m>g9 ( ! nebula ev5 ! v f9e/ du/ w no long] be ma9ta9$ 9 susp5sion by ! greatly weak5$ radiation pressure4 ,?us we arrive at an out] limit = ! nebula4 ,! o!r circum/ance is ! viol5t rotation :i* is set up by ! impact ( ! c5tral bodies4 ,! rotation & ! c5trifugal =ces w produce a disk-%ap$ expansion ( ! :ole c5tral mass4 ,ow+ to molecul> collisions & to tidal effects1 ! angul> velocity w 9 ! d5s] portions t5d to become uni=m1 s t ! :ole w rotate l a flatt5$-out ball fill$ ) gas1 & ! spiral /ructure w gradually disappe> 9 ^? p>ts4 ,9 ! m remote p>ticles ! velocity w only increase to su* an ext5t z to equal t ( a planet mov+ at ! same di/ance--t is to say1 ! gravitation t[>ds ! c5tral body w be balanc$ by ! c5trifugal =ce1 & at ! v greate/ di/ances ! molecul> bomb>dm5ts1 z well z gravitation t[>ds ! c5tre1 w become s insignificant t any masses collect$ !re w reta9 _! %ape = an almo/ unlimit$ space ( "t4 ,9 ! c5tre ( ?is sy/em ! ma9 bulk ( ! matt] w\ld be conc5trat$ 9 a sun ( extreme brightness1 ^: light int5sity w\ld1 h[ev]1 ow+ to /rong radiation1 dim9i% ) comp>ative rapidity4 ,illu/ration3 ,fig4 #ec4--,nebul> /ri 9 ! ,swan4 ,new ,g5]al ,catalogue1 #fiib4 ,tak5 at ! ,y]kes ,obs]vatory on ,octob] #e1 #aija4 ,scale1 #a mm4 #da sec4 ( arc ,su* an ext5sive nebul> sy/em1 9 :i* gravitation1 on acc\nt ( ! enorm\s di/ances1 w\ld act feebly & v sl[ly1 w\ld yet1 9 spite ( ! extraord9>y att5uation ( matt] 9 its out] portions1 & j on acc\nt ( its va/ ext5sion1 be able to /op ! movem5t ( ! p>ticles ( du/ p5etrat+ into x4 ,if ! gases ( ! nebula are n to escape into space1 not)/&+ ! inf9itesimal gravitation1 _! molecules mu/ be assum$ to be almo/ at a /&-/ill1 & _! temp]ature mu/ n rise by m ?an #ej or #fj ,c5t4 above absolute z]o4 ,at su* l[ temp]atures ! s-call$ adsorption plays an enorm\sly important "p 7,dew>74 ,! small du/ p>ticles =m c5tres ab\t :i* ! gases are cond5s$ to a rem>kable degree4 ,! extremely l[ d5sity ( ^! gases does n prev5t _! cond5sation2 = ! adsorption ph5om5on foll[s a law accord+ to :i* ! mass ( cond5s$ gas w only be r$uc$ by ab\t "o-t5? :5 ! d5sity ( ! surr\nd+ gas has be5 decreas$ by "o-t5-?\s&?4 ,! mass ( du/ p>ticles or du/ gra9s w ?us be augm5t$1 & :5 !y collide !y w be cem5t$ toge!r by ! semiliquid films cond5s$ ^u !m4 ,!re mu/1 h5ce1 be a relatively en]getic =mation ( meteorites 9 ! nebul1 & especially 9 _! int]iors4 ,!n />s & _! satellites1 migrat+ ?r\gh space1 w /ray into ^! sw>ms ( gases & meteorites )9 ! nebul4 ,! l>g] & m rapidly mov+ cele/ial bodies w cru% ?r\gh ?is relatively less d5se matt]2 b ?\s&s ( ye>s may yet be occupi$ 9 _! pass+ ?r\gh nebul ( va/ dim5sions4 ,illu/ration3 ,fig4 #ed4--,nebula & /> rift 9 ! ,swan1 9 ! ,milky ,way4 ,tak5 by ,m4 ,wolf1 ,knig/uhl1 ne> ,heidelb]g ,illu/ration3 ,fig4 #ee4--;,great nebula ne> ,rho1 9 ,ophiu*us4 ,photograph by ,e4 ,e4 ,b>n>d1 ,lick ,obs]vatory4 ,!re are sev]al empty spots & rifts ne> ! l>g] />s ( ! nebula ,an extraord9>ily int]e/+ photograph obta9$ by ! celebrat$ ,pr(essor ,max ,wolf1 ( ,heidelb]g1 %[s u a "p ( ! nebula 9 ! ,swan into :i* a /> has p5etrat$ f outside4 ,! intrud] has collect$ ab\t x ! nebul\s matt] x met on its way1 & has ?us left an empty *annel beh9d x m>k+ its track4 ,simil> spots ( va/ ext5t1 relatively devoid ( nebul\s matt]1 occur v frequ5tly 9 ! irregul> nebul2 !y are frequ5tly call$ 8fissures10 or by ! specifically ,engli% t]m 8rifts10 because !y h g5]ally a long-drawn-out appe>ance4 ,! presumption t ^! rifts repres5t ! tracks ( l>ge cele/ial bodies :i* h cut _! way ?r\gh widely exp&$ nebul> masses 7,fig4 #ed7 has be5 ent]ta9$ = a long "t4 ,illu/ration3 ,fig4 #ef4--,/> clu/] 9 ,h]cules4 ,messi] #ac4 ,tak5 at ! ,y]kes ,obs]vatory4 ,scale1 #a mm4 #i4bb sec4 ( arc ,! small] & m sl[ly mov+ immigrants1 on ! o!r h&1 are /opp$ by ! p>ticles ( ! nebul4 ,we !re=e see ! />s m sp>sely di/ribut$ 9 ! imm$iate neighborhood ( ! nebul1 :ile 9 ! nebul !mselves !y appe> m d5sely cr[d$4 ,?is fact _h /ruck ,h]s*el 9 8 obs]vations ( nebul2 9 rec5t days x has be5 inve/igat$ by ,c\rvoisi] & ,m4 ,wolf4 ,9 ?is way sev]al c5tres ( attraction are creat$ 9 a nebula2 !y cond5se ! gases surr\nd+ ! nebula1 & cat*1 s to say1 any /ray meteorites & collect !m especially 9 ! inn] portions ( ! nebula4 ,we frequ5tly obs]ve1 fur!r1 h[ ! nebul> matt] appe>s att5uat$ at a c]ta9 di/ance f ! lum9\s bright />s 7comp>e ,figs4 #eb & #ee74 ,f9ally1 ! nebul *ange into /> clu/]s :i* /ill reta9 ! *>act]i/ic %apes ( ! nebul2 ( ^! ! spiral is ! mo/ usual1 :ile we also meet ) conical %apes1 orig9at+ f conical nebul1 & sph]ical %apes 7comp>e ,figs4 #ef1 #eg1 & #eh74 ,?is is1 broadly1 ! type ( evolution ?r\gh :i* ,h]s*el1 rely+ ^u 8 obs]vations1 presum$ a nebula to pass4 ,he 01 h[ev]1 "u ! impression t ! nebul\s matt] w\ld directly be cond5s$ into /> clu/]s )\t ! aid ( /range cele/ial immigrants4 ,illu/ration3 ,fig4 #eg4--,/> clu/] 9 ,pegasus4 ,messi] #ae4 ,tak5 at ! ,y]kes ,obs]vatory4 ,scale1 #a mm4 #f4d sec4 ( arc ,x has be5 kn[n s9ce ! mo/ anci5t times1 & has be5 confirm$ by ! obs]vations ( ,h]s*el & o!rs 9 a mo/ conv9c+ mann]1 t ! />s are /rongly conc5trat$ ab\t ! middle l9e ( ! ,milky ,way4 ,x is n improbable t !re 0 orig9ally a nebula ( enorm\s dim5sions 9 ! plane ( ! ,milky ,way1 produc$ possibly by ! collision ( two su* giant suns z ,arcturus4 ,?is gigantic nebula has ga!r$ up ! small] migrat+ cele/ial bodies :i*1 9 _! turn1 h cond5s$ ^u !mselves nebul> matt]1 & h !reby become inc&esc5t1 if !y 7 n s be=e4 ,! rotational movem5t 9 ^? p>ts :i* 7 f> remov$ f ! c5tre ( ! ,milky ,way may be neglect$4 ,at a lat] p]iod collisions succe$$ betwe5 ! s+le />s :i* _h be5 ga!r$ up1 & x is = ?is reason t gase\s nebul1 z well z new />s1 are comp>atively frequ5t ph5om5a 9 ! plane ( ! ,milky ,way4 ,?is view may "s day receive confirmation1 :5 we succe$ 9 prov+ ! exi/5ce ( a c5tral body 9 ! ,milky ,way1 evid5ce ( :i* might possibly be d$uc$ f ! curvature ( ! orbits ( ! sun or ( o!r />s4 ,illu/ration3 ,fig4 #eh4--;,cone-%ap$ /> clu/] 9 ,gem9i4 ,z reg>ds ! r+-%ap$ nebula 9 ! ,lyre 7,fig4 #ej71 ! mo/ rec5t measurem5ts made by ,newkirk po9t to ! result t ! /> visible 9 its c5tre is di/ant f u ab\t ?irty-two light-ye>s4 ,z x appe>s probable t ?is /> really =ms ! c5tral core ( ! nebula1 ! di/ance ( ! nebula itself mu/ be ?irty-two light-ye>s4 ,f ! diamet] ( ! r+-%ap$ nebula :i* ,newkirk e/imates at "o m9ute ( arc1 ?is a/ronom] has calculat$ t ! di/ance ( ! r+ f its c5tral body is equal to ab\t ?ree hundr$ times ! radius ( ! e>?'s orbit--t is to say1 ! r+ is ab\t t5 times z f> f its sun z ,neptune is f our sun4 ,!re is a fa9t lum9esc5ce )9 ?is r+4 ,! nebul> matt] may orig9ally h be5 m conc5trat$ at ?is spot ?an 9 ! out] portions ( ! r+ itself4 ,b ?is mass 0 probably cond5s$ on meteors :i* immigrat$ f outside1 & :5 ^! meteors coalesc$ d>k planets 7 produc$ :i* move ab\t ! c5tral body1 & :i* h ga!r$ ab\t !m mo/ ( ! gases4 ,if t c5tral body 7 z heavy z our sun1 ! matt] 9 ! r+ %\ld revolve ab\t x 9 five ?\s& ye>s4 ,t rotation w\ld suffice to wipe out ! orig9al spiral %ape1 en\gh ( :i* has yet be5 left to p]mit ( our di/9ctly disc]n+ ! two w+s ( ! spiral4 ,! c5tral body ( ?is r+-%ap$ nebula gives a cont9u\s spectrum ( bright l9es :i* is p>ticul>ly develop$ on ! violet side4 ,! /> w\ld !re=e appe> to be mu* y\ng] & mu* hott] ?an our sun1 & its radiation pressure w\ld !re=e be mu* m int5se4 ,! p]iod ( rotation ( ! nebula may1 = ?is reason1 h to be e/imat$ at a consid]ably high] figure4 ,! em95t ,dut* a/ronom] ,kapteyn has d$uc$ f ! prop] motions ( #afh nebul t _! av]age di/ance f ! e>? is ab\t sev5 hundr$ light-ye>s & equal to t ( />s ( ! t5? magnitude4 ,! old idea1 t ! nebul mu/ be inf9itely f>!r remov$ f u ?an ! fa9t] />s1 w\ld !re=e appe> to be errone\s4 ,accord+ to ! measurem5ts ( ,pr(essor ,bohl91 ! nebula 9 ,&rom$a may inde$ be at a di/ance ( n m ?an =ty light-ye>s4 ,! 8new />s0 =m a gr\p among ! peculi> cele/ial bodies :i* on acc\nt ( _! v>iable light int5sity h be5 designat$ z 8v>iable />s10 & ( :i* a few typical cases %\ld be m5tion$1 because a great sci5tific int]e/ atta*es to ^! problems4 ,! /> ,eta1 9 ,argus1 may be said to illu/rate ! /range fate t a /> has to pass ?r\gh :5 x has drift$ into a nebula fill$ ) immigrat$ cele/ial bodies4 ,x is "o ( ! mo/ peculi> v>iable />s4 ,! /> %9es ?r\gh "o ( ! l>ge/ nebul> cl\ds 9 ! heav5s4 ,:e!r x /&s 9 any physical connection ) its surr\nd+s _c be /at$ )\t fur!r exam9ation4 ,! /> might1 = in/ance1 be at a consid]able di/ance 9 front ( ! nebula1 betwe5 ! latt] & ourselves4 ,its frequ5t *ange 9 light int5sity sugge/s1 h[ev]1 a s]ies ( collisions1 :i* d n appe> unnatural to u :5 we suppose t ! /> is )9 a nebula into :i* _m cele/ial bodies h drift$4 ,z ?is /> belongs to ! s\!rn hemisph]e1 x 0 n obs]v$ be=e our a/ronom]s comm5c$ to visit t hemisph]e4 ,9 #afgg x 0 class$ z a /> ( ! f\r? magnitude2 t5 ye>s lat] x 0 ( ! second magnitude2 ! same 9 #agea4 ,9 #ahbg x 0 ( ! fir/ magnitude1 & x 0 f\nd to be v>iable--t is to say1 x %one ) v>iable brightness4 ,h]s*el obs]v$ t x fluctuat$ betwe5 ! fir/ & second magnitudes1 & t x increas$ 9 brightness aft] #ahcg1 s t x 0 by #ahch ( magnitude #j4b4 ,aft] t x began to decrease 9 int5sity up to ,april1 #ahci1 :5 x _h ! magnitude #a4a4 ,x rema9$ = f\r ye>s approximately at ?is int5sity2 !n x increas$ rapidly aga9 9 #ahdc1 & surpass$ all />s except ,sirius 7magnitude -#a4g74af ,aft]w>ds its int5sity sl[ly dim9i%$ once m1 s t x rema9$ j visible to ! nak$ eye 7six? magnitude72 by #ahfi x _h become invisible4 ,s9ce !n x has be5 fluctuat+ betwe5 ! six? & sev5? magnitudes4 ,footnote #af3 ,?is figure1 -#a4g1 signifies t ! brightness ( ,sirius is #b4ebb4g #ab times great] ?an t ( a /> ( magnitude #a4 ,next to ,sirius comes ,canopus1 ) magnitude -#a4j1 be+ #f4c times bright] ?an a /> ( magnitude #a4 ,! la/ *anges 9 ! int5sity ( ?is /> /rongly recall ! behavior ( ! new /> 9 ,p]seus1 only t ! latt] has be5 pass+ ?r\gh its phases at a mu* m rapid rate4 ,x appe>s to be c]ta91 h[ev]1 t ,eta1 9 ,argus1 0 f ! v beg9n+ f> bright] ?an ,nova ,p]sei1 & t at lea/ once be=e ! great collision 9 #ahdc 7aft] :i* x 0 surr\nd$ by obscur+ cl\ds ( increas+ opacity7--namely1 9 ,janu>y1 #ahch1 x _h be5 expos$ to a slight collision ( quickly vani%+ effect4 ,?is less] collision 0 probably ( ! k9d :i* ,may] imag9$ = ! e>? & sun4 ,x w\ld give rise to heat developm5t correspond+ to ! heat exp5diture ( ! sun 9 ab\t a hundr$ ye>s4 ,z x _h be5 obs]v$ t ! /> 0 v>iable 9 an irregul> mann] be=e t1 we may1 p]haps1 presume t x _h already und]gone ano!r collision4 ,accord+ to ! obs]vations ( ,borisiak1 a /ud5t 9 ,kief1 ! new /> 9 ,p]seus w\ld h be51 on ! ev5+ ( ,febru>y #ba1 #aija1 ( #a4e magnitude1 :ile a few h\rs previ\sly x _h be5 ( magnitude #ab1 & ! foll[+ ev5+ ( magnitude #b4g2 aft]w>ds its int5sity increas$ up to ! foll[+ ev5+1 :5 x out%one all ! o!r />s 9 ! nor!rn sky4 ,if ?is /atem5t is n bas$ on errone\s obs]vations1 ! new /> mu/ h be5 9 collision ) ano!r cele/ial body two days be=e its great collision1 p]haps ) a small planet 9 ! neighborhood ( ! sun1 ) :i* x lat] collid$4 ,t w\ld acc\nt = its tempor>y brilliancy4 ,new />s are by no means s r>e z "o might p]haps assume4 ,almo/ e ye> "s new /> is discov]$4 ,by f> mo/ ( ^! are se5 9 ! neighborhood ( ! ,milky ,way1 :]e ! visible />s are unusually cr[d$1 s t a collision :i* w\ld become visible to u may easily occur4 ,= simil> reasons we f9d !re also mo/ ( ! gase\s nebul4 ,mo/ ( ! /> clu/]s are also 9 ! neighborhood ( ! ,milky ,way4 ,?is is 9 consequ5ce ( ! facts j allud$ to4 ,! nebul :i* are produc$ by collisions betwe5 two suns are soon cross$ by migrat+ cele/ial bodies su* z meteorites or comets1 :i* !re occur 9 l>ge numb]s2 by ! cond5s+ action ( ^! intrud]s !y are !n trans=m$ into /> clu/]s4 ,9 p>ts ( ! heav5s :]e />s are relatively sp>se 7z at a great di/ance f ! ,milky ,way71 mo/ ( ! nebul obs]v$ exhibit /ell> spectra4 ,!y are no?+ b /> clu/]s1 s f> remov$ f u t ! sep>ate />s c no long] be di/+ui%$4 ,t s+le />s & gase\s nebul are s r>ely p]ceiv$ 9 ^! regions is1 no d\bt1 due to _! great di/ance4 ,among ! v>iable />s we f9d q a numb] :i* display consid]able irregul>ity 9 _! fluctuations ( brightness1 & :i* rem9d u ( ! new />s4 ,to ?is class belongs ! j-m5tion$ /> ,eta1 9 ,argus4 ,ano!r example 7! fir/ "o :i* 0 recogniz$ z 8v>iable07 is ,mira ,ceti1 :i* may be translat$1 8,! ,wond]ful ,/> 9 ! ,con/ellation ( ! ,:ale40 ,?is my/]i\s body 0 discov]$ by ! ,frisian prie/ ,fabricius1 on ,augu/ #ab1 #aeif1 z a /> ( ! second magnitude4 ,! prie/1 an exp]i5c$ a/ronom]1 _h n previ\sly notic$ ?is />1 & he look$ = x 9 va9 9 ,octob]1 #aeig4 ,9 ! ye>s #afch & #afci ! v>iability ( ! /> 0 recogniz$1 & x 0 soon asc]ta9$ to be irregul>4 ,! p]iod has a l5g? ( ab\t elev5 mon?s1 b x fluctuates irregul>ly ab\t ?is figure z a mean value4 ,at its greate/ int5sity ! /> ranks ) ^? ( ! fir/ or second ord]4 ,sometimes x is weak]1 b x is always ( m ?an ! fif? magnitude4 ,t5 weeks aft] a maximum ! /> is no long] visible1 & its brightness may dim9i% to magnitude #i4e4 ,9 o!r words1 its int5sity v>ies ab\t 9 ! ratio ( #a3 #ajjj 7or possibly m74 ,aft] a m9imum ! brightness once m increases1 ! /> becomes visible aga9--t is to say1 x atta9s ! six? magnitude--& aft] ano!r six weeks x w once m be at its maximum4 ,we h evid5tly to deal ) sev]al sup]pos$ p]iods4 ,! spectrum ( ?is /> is r peculi>4 ,x belongs to ! r$ />s ) a b& spectrum :i* is cross$ by bright hydrog5 l9es4 ,! /> is rec$+ f u ) a velocity ( n less ?an #fc km4 7#ci miles7 p] second4 ,! bright hydrog5 l9es :i* correspond to ! spectrum ( ! nebula may sometimes be resolv$ into ?ree compon5ts1 ( :i* ! middle "o corresponds to a mean velocity ( #fj km41 & ! two o!rs h v>iable rec$+ velocities ( #ce & #hb km4--t is to say1 velocities ( #be or #bb km4 less or m ?an ! mean velocity4 ,evid5tly ! /> is surr\nd$ by ?ree nebul2 "o is conc5trat$ ab\t its c5tre2 ! two o!rs lie on a r+ ! matt] ( :i* has be5 conc5trat$ on two opposite sides4 ,! r+1 :i* recalls ! r+ nebula 9 ! ,lyre1 seems to move ab\t ! /> ) a velocity ( #bc4e km4 p] second4 ,z ?is revolution is accompli%$ )9 elev5--or1 m correctly1 )9 tw5ty-two mon?s1 s9ce !re mu/ be two maxima & two m9ima dur+ "o revolution--! total circumf]5ce ( ! r+ w be #bc4e #hf1djj #fgj--acfa millions1 & ! radius ( its orbit #bag million km41 :i* is #a4de times great] ?an ! radius ( ! e>?'s orbit4 ,n[ ! velocity ( ! e>? 9 its orbit is #bi4e km4 7#ah4c miles7 p] second4 ,a planet at #a4de times t di/ance f ! sun w\ld h ! 7#a4bjc times small]7 velocity ( #bd4e km4 p] second1 :i* is approximately t ( ! hypo!tical r+ ( ,mira ,ceti4 ,we conclude1 !re=e1 t ! mass ( ! c5tral sun 9 ,mira ,ceti w ne>ly equal ! mass ( our sun4 ,! calculation really sugge/s t ,mira w\ld be ab\t eight p] c5t4 small]2 b ! diff]5ce lies )9 ! range ( ! probable error4 ,*&l] has direct$ att5tion to a /rik+ regul>ity 9 ^! />s4 ,! long] ! p]iod ( _! v>iation1 ! r$d] 9 g5]al _! color4 ,?is is easily compreh5d$4 ,! d5s] ! orig9al atmosph]e1 ! m widely ! gases w h ext5d$ outw>d f ! />1 & ! m du/ w h be5 caught or secret$ by x4 ,we h se5 t ! limb ( ! sun has a r$di% light because ( ! quantities ( du/ 9 ! sol> atmosph]e4 ,! effect is *iefly to be ascrib$ to ! absorption ( ! blue rays by ! du/2 b x may p>tly be expla9$ on ! assumption t ! sol> radiations r5d] ! du/ inc&esc5t1 ?\gh its temp]ature may be l[] ?an t ( ! photosph]e1 because ! du/ lies outside ! sun1 & t x w !re=e emit a relatively r$di% light4 ,! m du/ !re is 9 a nebula1 ! r$d] w be its lum9esc5ce2 & z ! quantity ( du/ increases 9 g5]al ) ! ext5sion ( ! nebula1 t /> :i* is surr\nd$ by wid] r+s ( nebul w 9 g5]al be m r$2 b ! great] ! radius ( ! r+1 ! long] also w 9 g5]al be its p]iod4 ,! s-call$ r$ />s %[1 9 addition to ! bright hydrog5 l9es1 b&$ spectra :i* indicate ! pres5ce ( *emical comp\nds4 ,on ?is acc\nt su* />s 7 =m]ly cr$it$ ) a l[] temp]ature4 ,b ! same peculi>ity is also obs]v$ 9 sun-spots1 al?\gh ! latt]1 on acc\nt ( _! position1 mu/ h a high] temp]ature ?an ! surr\nd+ photosph]e4 ,! pres5ce ( b&s 9 ! spectrum c]ta9ly sugge/s high pressure1 h[ev]4 ,! r$ />s are evid5tly surr\nd$ by a v ext5sive atmosph]e ( gases1 9 ! inn] portions ( :i* ! pressure is s high t ! atoms ent] into comb9ation4 ,! spectra ( ! r$ />s display1 on ! :ole1 a /rik+ resemblance to ^? ( ! sun-spots4 ,! violet portion ( ! spectrum is weak5$1 because ! masses ( du/ h ext+ui%$ ?is light4 ,ow+ to ! l>ge masses ( du/ :i* lie 9 our l9e ( sight1 ! spectrum l9es are 9 bo? cases m>k$ly wid5$ & sometimes accompani$ by bright l9es4 ,ano!r class ( />s1 di/+ui%$ by bright l9es1 comprises ^? /udi$ by ,wolf & ,rayet1 & nam$ aft] !m4 ,^! />s are *>act]iz$ by a hydrog5 atmosph]e ( enorm\s ext5sion1 l>ge en\gh 9 "s cases1 x has be5 calculat$1 to fill up ! orbit ( ,neptune4 ,^! />s are evid5tly ei!r hott] & m /rongly radiat+ ?an ! r$ />s1 or !re is n s mu* du/ 9 _! neighborhood--! du/ may possibly h be5 expell$ by ! /rong radiat+ pressure4 ,!y are1 !re=e1 class$ ) ! yell[1 & n ) ! r$ />s4 ,al?\gh !re is e reason to suppose t _! c5tral bodies are at lea/ z hot z ^? ( ! :ite />s1 ! du/ is yet able to r$uce ! color to yell[1 ow+ to ! va/ ext5sions ( _! atmosph]es4 ,! unequal p]iods 9 />s l ,mira may be expla9$ by ! supposition t !re are sev]al r+s ( du/ mov+ ab\t !m1 z 9 ! case ( ! planet ,saturn4 ,9 ! case ( ! inn] r+s :i* h a %ort p]iod1 !re has probably be5 suffici5t "t dur+ ! unc\nt$ numb] ( revolutions to effect a uni=m di/ribution ( ! du/4 ,h5ce we d n disc]n any notewor?y nuclei 9 !m1 su* z we obs]ve 9 ! tails ( comets2 ! du/ r+s only help to imp>t to ! /> a uni=m r$di% hue4 ,9 ! out] r+s ! di/ribution ( du/ w1 h[ev]1 n be uni=m4 ,"o ( ! r+s may be responsible = ! *ief prop] p]iod4 ,by ! co-op]ation ( o!r less important du/ r+s1 ! maximum or m9imum1 we %all easily und]/&1 may be displac$1 & ?us ! "t int]val betwe5 ! maxima & m9ima be alt]$4 ,?is alt]ation ( ! p]iod is s /rong = "s />s t we h n yet succe$$ 9 e/abli%+ any simple p]iodicity4 ,! be/-kn[n /> ( ?is type is ! bright-r$ /> ,betelgeuse 9 ! con/ellation ( ,orion4 ,! brightness ( ?is /> fluctuates irregul>ly betwe5 ! magnitudes #a4j & #a4d4 ,by f> ! l>ge/ numb] ( v>iable />s belong to ! type ( ,mira4 ,o!rs resemble ! v>iable /> ,beta 9 ! con/ellation ( ! ,lyre1 & ?us belong to ! ,lyre type4 ,! v>iability ( ! spectra ( a great _m ( ^! />s indicates t !y mu/ be mov+ ab\t a d>k /> z companion1 or r t !y bo? move ab\t a common c5tre ( gravity4 ,! *ange 9 ! light int5sity is1 z a rule1 expla9$ by ! supposition t ! bright /> is p>tially obscur$ at times by its d>k companion4 ,_m irregul>ities1 h[ev]1 9 _! p]iods & o!r circum/ances prove t ?is explanation is n suffici5t4 ,! assumption ( r+s ( du/ circulat+ ab\t ! /> & ( l>g] cond5sation c5tres af=ds a bett] elucidation ( ! v>iability ( ^! />s4 ,!y are gr\p$ ) ! :ite or yell[ />s1 9 ^: surr\nd+s ! du/ does n play s l>ge a "p z 9 t ( ,mira ,ceti4 ,! p]iod ( _! v>iability is1 z a rule1 v %ort1 moreov]--g5]ally only a few days 7! %orte/ kn[n1 only f\r h\rs7--:ile ! p]iod ( ! ,mira />s am\nts to at lea/ sixty-five days1 & may atta9 two ye>s4 ,!re may be /ill long] p]iods s f> n inve/igat$4 ,ne>ly relat$ to ! ,lyre />s are ! ,algol />s1 ^: v>iability c be expla9$ by ! assumption t ano!r bright or d>k /> is mov+ )9 _! vic9ity1 p>tially cutt+ (f _! light4 ,!re is no du/ 9 ^! cases1 & ! spectrum *>act]izes ^! />s z />s ( ! fir/ class--t is1 z :ite />s--s f> z !y h be5 /udi$ up to ! pres5t4 ,we mu/ presume = all ! v>iable />s t ! l9e ( sight f ! obs]v] to ! /> falls 9 ! plane ( _! du/ r+s or ( _! companions4 ,if ?is 7 n s1 !y w\ld appe> to u l a nebula ) a c5tral cond5sation nucleus1 or1 s f> z ,algol />s are conc]n$1 l ! s-call$ spectroscopic d\bles ^: motion ab\t ea* o!r is recogniz$ f ! displacem5t ( _! spectral l9es4 ,! evolution ( />s f ! nebul\s /ate has be5 depict$ by ! fam\s *ief ( ! ,lick ,obs]vatory1 9 ,cali=nia1 ,w4 ,w4 ,campbell1 z foll[s 7comp>e ! spectra ( ! />s ( ! #b;d1 #c;d1 & #d? class1 ,figs4 #ei & #fj73 ,illu/ration3 #gd ,my1 9 ,sun #bhj ,s*jell]up's ,gem9i ,class #b ,s*jell]up's ,catalogue ,class #c ,catalogue ,class #d ,class #d ,fig4 #ei4--;,comp>ison ( spectra ( />s ( classes #b1 #c1 #d4 ,aft] photographs tak5 at ! ,y]kes ,obs]vatory4 ,blue portions ( spectrum4 ,wave-l5g?s 9 million?s ( a millimetre ,illu/ration3 #bhj ,sun ,my1 9 #gd ,s*jell]up's ,class #b ,gem9i ,s*jell]up's ,catalogue ,class #c ,catalogue ,class #d ,class #d ,fig4 #fj4--;,comp>ison ( spectra ( />s ( classes #b1 #c1 #d4 ,aft] photographs tak5 at ! ,y]kes ,obs]vatory4 ,gre5 & yell[ portions ( spectrum4 ,wave-l5g?s 9 million?s ( a millimetre 8,x is n difficult to select a long li/ ( well-kn[n />s :i* _c be f> remov$ f nebul> conditions4 ,^! are ! />s conta9+ bo? ! ,hugg9s & ! ,pick]+ s]ies ( bright hydrog5 l9es1 ! bright l9es ( helium1 & a few o!rs n yet id5tifi$4 ,gamma ,argus & ,zeta ,puppis are ( ?is class4 ,ano!r is ,,dm #cj4cfci1 :i* is actually surr\nd$ ) a sph]ical atmosph]e ( hydrog5 "s five seconds ( arc 9 diamet]4 ,a little fur!r remov$ f ! nebul> /ate are ! />s conta9+ bo? bright & d>k hydrog5 l9es--caught1 s to speak1 9 ! act ( *ang+ f bright-l9e to d>k-l9e />s4 ,gamma ,cassiopei1 ,pleione1 & ,my ,c5tauri are examples4 ,closely relat$ to ! =ego+ are ! helium />s4 ,_! absorption l9es include ! ,hugg9s hydrog5 s]ies complete1 a score or m ( ! conspicu\s helium l9es1 frequ5tly a few ( ! ,pick]+ s]ies1 & usually "s inconspicu\s metallic l9es4 ,! :ite />s 9 ,orion & 9 ! ,pleiades are typical ( ?is age4 8,! assignm5t ( ! =ego+ types to an e>ly place 9 /ell> life 0 fir/ made ^u ! evid5ce ( ! spectroscope4 ,! photographic discov]y ( nebul\s masses 9 ! regions ( a l>ge proportion ( ! bright-l9e & helium />s af=ds extremely /rong confirmation ( _! y\?4 ,:o t has se5 ! nebul\s backgr\nd ( ,orion 7,fig4 #ea7 or ! remnants ( nebulosity 9 :i* ! individual />s ( ! ,pleiades 7,fig4 #eb7 are imm]s$ c d\bt t ! />s 9 ^! gr\ps are ( rec5t =mation8 8,) ! lapse ( "t1 /ell> heat radiates into space1 &1 s f> z ! individual /> is conc]n$1 is lo/4 ,on ! o!r h&1 ! =ce ( gravity on ! surface /rata increases4 ,! inevitable contraction is accompani$ by increas+ av]age temp]ature4 ,*anges 9 ! spectrum are ! necess>y consequ5ce4 ,! second hydrog5 s]ies vani%es1 ! ord9>y hydrog5 absorption is int5sifi$1 ! helium l9es become indi/9ct1 & calcium & iron absorptions beg9 to ass]t !mselves4 ,vega & ,sirius are conspicu\s examples ( ?is p]iod4 ,increas+ age gradually robs ! hydrog5 l9es ( _! importance1 ! ,h & ,k l9es broad51 ! metallic l9es develop1 ! blui%-:ite color fades 9 ! direction ( ! yell[1 &1 aft] pass+ ?r\gh types exemplifi$ by _m well-kn[n />s1 ! sol> /age is rea*$4 ,! rev]s+ lay] 9 sol> />s repres5ts b f\r or five hydrog5 l9es ( mod]ate int5sity2 ! calcium l9es are comm&+ly p]man5t1 & "s tw5ty ?\s& metallic l9es are visible4 ,! sol> type seems to be ne> ! summit ( /ell> life4 ,! av]age temp]ature ( ! mass mu/ be ne>ly a maximum2 = ! l[ d5sity indicates a con/itution t is /ill gase\s comp>e ,*apt] ,,vii44 8,pass+ "t br+s a l[]+ ( ! av]age temp]ature4 ,! color passes f yell[ to r$1 9 consequ5ce ( l[] radiation1 temp]ature1 & increas+ g5]al absorption by ! atmosph]e4 ,! hydrog5 l9es become indi/9ct1 metallic absorption rema9s p]man5t1 & broad absorption b&s are introduc$4 ,9 "o type 7,sec*i's ,type ,,iii471 ( :i* ,alpha ,h]culis is an example1 ^! b&s are ( unkn[n orig94 ,9 ano!r class 7,sec*i's ,type ,,iv471 illu/rat$ by ! /> #ai ,piscium1 !y h be5 def9itely id5tifi$ z ( c>bon orig94 8,!re is sc>cely room = d\bt t ^! types ( />s 7,type ,,iv47 are approa*+ ! la/ /ages ( /ell> developm5t4 ,surface temp]atures h be5 l[]$ to ! po9t ( p]mitt+ m complex *emical comb9ations ?an ^? 9 ! sun4 8,sec*i's ,type ,,iii4 includes ! sev]al numb]$ long-p]iod v>iable />s ( ! ,mira ,ceti class1 ^: spectra at maximum brilliancy %[ sev]al bright l9es ( hydrog5 & o!r *emical elem5ts4#ag ,x is significant t ! dull-r$ />s are all v fa9t2 !re are none bright] ?an magnitude #e4e4 ,_! effective radiatory p[] is und\bt$ly v l[40 ,footnote #ag3 ,?is circum/ance indicates t ! r$ color ( ^! />s1 z we h already rem>k$ ) reg>d to ,mira ,ceti1 is n to be trac$ back to a l[ temp]ature1 b r to ! du/ surr\nd+ !m4 ,! mo/ extraord9>y brightness ( "s />s1 l ,arcturus & ,betelgeuse1 :i* are r$d] ?an ! sun1 & ^: spectra1 accord+ to ,hale1 resemble ^? ( ! sun-spots1 presuppose a v high temp]ature4 ,! *>act]i/ic l9es ( _! spectra are produc$ by ! relatively cool vapors ( _! out] portions4 ,! /ate ( evolution1 :i* succe$s t *>act]iz$ z ! ,sec*i ,type ,,iv41 may be elucidat$ ) ! aid ( ! examples ( ,jupit] & ! e>?1 ) :i* we are m famili>4 ,^! planets w\ld be invisible if !y 7 n %9+ 9 borr[$ light4 ,jupit] has n advanc$ s f> z ! e>?4 ,! specific gravity ( ,jupit] is some:at l[] ?an t ( ! sun 7#a4bg aga9/ #a4ch71 &1 ap>t f ! cl\ds 9 its atmosph]e1 ?is planet is probably altoge!r 9 a gase\s condition1 :ile ! e>?1 ) its mean d5sity ( #e4eb1 possesses a solid cold cru/1 enclos+ its inc&esc5t int]ior4 ,?is /ate ( ! e>? corresponds to ! la/ /age 9 ! evolution ( ! />s4 ,( ! /reams ( gase\s matt] :i* are eject$ :5 />s collide ) "o ano!r1 ! metallic vapors are rapidly cond5s$ by cool+2 only helium & hydrog5 w rema9 9 ! gase\s condition & =m nebul> masses ab\t ! c5tral body4 ,^! nebul yield bright lights4 ,_! lum9osity is due to ! negative p>ticles :i* are s5t to !m by ! radiation pressure ( ne> />s1 & especially by ! c5tral bodies ( ! nebula4 ,) ! new />s :i* h s f> be5 obs]v$1 ?is pressure ( radiation soon dim9i%es1 & ! nebul> light likewise decreases 9 su* cases4 ,9 o!r in/ances1 z ) ! />s *>act]iz$ by bright hydrog5 & helium l9es1 ! radiation ( ! c5tral body or />s 9 _! vic9ity seems to be ma9ta9$ at full =ce = long p]iods4 ,! nebul\s accumulations ( helium & hydrog5 w gradually escape & be cond5s$ 9 ne>-by />s "u ! =mation ( 8explosive0 comp\nds4 ,! t5d5cy to ent] into comb9ation seems to be /ronge/ 9 ! case ( helium2 x disappe>s fir/ f ! /ell> atmosph]e4 ,t helium ent]s into comp\nds at high temp]atures seems to foll[ f ! rese>*es ( ,ramsay1 ,cooke1 & ,kohls*tt]4 ,hydrog5 w aft]w>ds be absorb$1 & ! light ( ! c5tral body w !n %[ ! pr$om9at+ occurr5ce ( ! vapors ( calcium & ( o!r metals 9 its atmosph]e4 ,simultane\sly ) ^!1 *emical comp\nds w be notic$1 among :i* ! c>bon comp\nds w play an important "p--9 ! out] portions ( ! sun-spots1 9 ! />s ( ! ,sec*i ,type ,,iv41 z well z 9 ! gase\s envelopes ( ! comets4#ah ,footnote #ah3 ,! pres5ce ( c>bon b&s 9 ! spectrum ne$ n be tak5 z a m>k ( l[ temp]ature4 ,crew & ,hale h obs]v$ t ^! b&s gradually vani%$ f an arc spectrum z ! temp]ature 0 l[]$ by decreas+ ! curr5t int5sity4 ,f9ally a cru/ w =m4 ,! /> is ext9ct4 ,,vii ,,! ,,nebul> ,,& ,,! ,,sol> ,,/ates ,we w n[ proce$ to a m intimate consid]ation ( ! *emical & physical conditions :i* probably *>act]ize ! nebul 9 di/9ction f ! suns4 ,^! prop]ties diff] 9 _m respects ess5tially f ^? :i* we are accu/om$ to associate ) matt] z inve/igat$ by u1 :i* may1 f ?is po9t ( view1 be /yl$ relatively conc5trat$4 ,! diff]5ces mu/ be fundam5tal4 ,= ! motto ( ,clausius1 :i* comprises ! sum ( our k ( ! nature ( heat1 _c apply to nebul4 ,?is motto reads3 8,! en]gy ( ! univ]se is con/ant4 ,! entropy ( ! univ]se t5ds to a maximum40 ,ev]ybody und]/&s :at is meant by en]gy4 ,we "k en]gy 9 _m =ms4 ,! mo/ important are3 en]gy ( position 7a heavy body has l>g] en]gy by virtue ( its hav+ be5 rais$ to a c]ta9 height above ! surface ( ! e>? ?an :5 x is ly+ on ! surface72 en]gy ( motion 7a dis*>g$ rifle-bullet has an en]gy :i* is proportional to ! mass ( ! bullet & to ! squ>e ( its velocity72 en]gy ( heat1 :i* is reg>d$ z ! en]gy ( ! motion ( ! smalle/ p>ticles ( a body2 electrical en]gy1 su* z c1 = in/ance1 be /or$ 9 an accumulator batt]y1 & :i*1 l all o!r modifications ( en]gy1 may be conv]t$ into en]gy ( heat2 & *emical en]gy1 su* z is display$ by a mixture ( eight grammes ( oxyg5 ) "o gramme ( hydrog51 :i* c be trans=m$ into wat] "u a /rong evolution ( heat4 ,:5 we say t ! en]gy ( a sy/em to :i* en]gy is n imp>t$ f outside is con/ant1 we m]ely mean t ! diff]5t =ms ( en]gy ( ! sep>ate p>ts ( ?is sy/em may be trans=m$ into o!r =ms ( en]gy1 b t ! sum total ( all ! en]gies mu/ always rema9 un*ang$4 ,accord+ to ,clausius ?is law is valid ?r\gh\t ! inf9ite space ( ! univ]se4 ,by entropy we und]/& ! quantity ( heat ( a body divid$ by its absolute temp]ature4 ,if a quantity ( heat1 ( ,q calories1 ( a body at a temp]ature ( #ajj 7absolute temp]ature1 #cgc7 passes ov] to ano!r body ( #j 7absolute temp]ature1 #bgc71 ! total entropy ( ! two w h be5 decreas$ by ,q_/#cgc1 & increas$ by ,q_/#bgc4 ,z ! latt] quantity is ! great]1 ! entropy ( ! :ole w h increas$4 ,by itself1 we "k1 heat always passes1 ei!r by radiation or by conduction1 f bodies ( high] temp]ature to bodies ( l[] temp]ature4 ,t evid5tly implies an increase 9 entropy1 & x is 9 agreem5t ) ! law ( ,clausius t entropy t5ds to increase4 ,! mo/ simple case ( heat equilibrium is t 9 :i* we place a numb] ( bodies ( unequal temp]atures 9 an enclosure :i* nei!r receives heat f outside nor communicates heat to ! outside4 ,9 "s way or o!r1 usually by conduction or radiation1 ! heat w pass f ! w>m] to ! cold] bodies1 until at la/ equilibrium ensues & all ! bodies h ! same temp]ature4 ,accord+ to ,clausius1 ! univ]se t5ds to t !rmal equilibrium4 ,if x be ev] atta9$1 all s\rces ( motion1 & h5ce ( light1 w h be5 exhau/$4 ,! s-call$ 8heat-dea?0 7,wrmetod7 w h come4 ,if ,clausius 7 "r1 h[ev]1 ?is heat-dea?1 we may object1 %\ld already h occurr$ 9 ! inf9itely long space ( "t t ! univ]se has be5 9 exi/5ce4 ,or we might argue t ! _w has n yet be5 9 exi/5ce suffici5tly long1 b t1 anyh[1 x _h a beg9n+4 ,t w\ld contradict ! fir/ "p ( ! law ( ,clausius1 t ! en]gy ( ! univ]se is con/ant2 = 9 t case all ! en]gy w\ld h orig9at$ 9 ! mom5t ( creation4 ,t is q inconceivable1 & we mu/ h5ce look = conditions = :i* ! entropy law ( ,clausius does n hold4 ,! fam\s ,scot* physici/ ,cl]k-,maxwell has conceiv$ ( su* a case4 ,imag9e a vessel :i* is divid$ by a p>tition into two halves1 bo? *>g$ ) a gas ( p]fectly uni=m temp]ature4 ,let ! p>tition be provid$ ) a numb] ( small holes :i* w\ld n all[ m ?an "o gas molecule to pass at a "t4 ,9 ea* hole ,maxwell places a small1 intellig5t be+ 7"o ( 8 8demons071 :i* directs all ! molecules :i* ent] into ! hole1 & :i* h a great] velocity ?an ! mean velocity ( all ! molecules1 to ! "o side1 & :i* s5ds to ! o!r side all ! molecules ( a small] velocity ?an ! av]age4#ai ,all ! undesirable molecules ! demon b>s by means ( a little flap4 ,9 ?is way all ! molecules ( a velocity great] ?an ! av]age may be collect$ 9 ! "o comp>tm5t1 & all ! molecules ( a less] velocity 9 ! o!r comp>tm5t4 ,9 o!r words1 heat--= heat consi/s 9 ! movem5ts ( molecules--w pass f ! "o con/antly cool+ side to ! o!r1 :i* is con/antly rais+ its temp]ature1 & :i* mu/ !re=e become w>m] ?an ! =m]4 ,footnote #ai3 ,! k9etic !ory ( gases imag9es all ! molecules ( a gas to be 9 con/ant motion4 ,! int]nal pressure ( ! gas dep5ds ^u ! mean velocity ( ! p>ticles2 b "s p>ticles w move at a great]1 & "s at a small] velocity ?an ! av]age4--,h4,b4 ,9 ?is in/ance heat w\ld !re=e pass f a cold] to a w>m] body1 & ! entropy w\ld dim9i%4 ,nature1 ( c\rse1 does n "k any su* intellig5t be+s4 ,nev]!less1 simil> conditions may occur 9 cele/ial bodies 9 ! gase\s /ate4 ,:5 ! molecules ( gas 9 ! atmosph]e ( a cele/ial body h a suffici5t velocity--:i* 9 ! case ( ! e>? w\ld be #aa km4 7#g miles7 p] second--& :5 !y travel outw>d into ! mo/ extreme /rata1 !y may pass f ! range ( attraction out into inf9ite space1 aft] ! mann] ( a comet1 :i*1 if end[$ ) suffici5t velocity :5 ne> ! sun1 mu/ escape f ! sol> sy/em4 ,accord+ to ,/oney1 x is 9 ?is way t ! moon has lo/ its orig9al atmosph]e4 ,?is loss ( gas is c]ta9ly imp]ceptible 9 ! case ( our sun & ( l>ge planets l ! e>?4 ,b x may play an important "p 9 ! h\sehold ( ! nebul1 :]e all ! radiation f ! hot cele/ial bodies is /or$ up1 & :]e1 ow+ to ! enorm\s di/ances1 ! re/ra9+ =ce ( gravity is exce$+ly feeble4 ,?us ! nebul w lose _! mo/ rapid molecules f _! out] portions1 & !y w !re=e be cool+ 9 ^! out] /rata4 ,?is loss ( heat is comp5sat$ by ! radiation f ! />s4 ,if1 n[1 !re 7 only nebul ( "o k9d 9 ! :ole univ]se1 ^? escap$ molecules w\ld f9ally l& on "s o!r nebula1 heat equilibrium w\ld ?us be e/abli%$ betwe5 ! diff]5t nebul1 & ! 8heat-dea?0 be realiz$4 ,b we h already rem>k$ t ! nebul enclose _m immigrat$ cele/ial bodies1 :i* are able to cond5se ! gases f _! neighborhood1 & :i* !reby assume a high] temp]ature4 ,! lo/ molecules ( gases may also /ray into ! va/ atmosph]e ( ^! gr[+ />s1 & ! cond5sation w !n be ha/5$ "u a cont9u\s l[]+ ( ! entropy4 ,by su* processes ! clock-"w ( ! univ]se may be ma9ta9$ 9 motion )\t runn+ d[n4 ,ab\t ! bodies :i* h drift$ into nebul1 & ab\t ! remnants ( new />s :i* lie inside ! nebul1 ! gases w ?us collect :i* _h =m]ly be5 scatt]$ ?r\gh ! out] portions ( ! nebula4 ,^! gases orig9ate f ! explosive comp\nds :i* _h be5 /or$ 9 ! int]ior ( ! new />s4 ,hydrog5 & helium are1 mo/ likely1 ! mo/ important ( ^!2 = !y are ! mo/ difficult to be cond5s$1 & c exi/ 9 notable quantities at extremely l[ temp]atures1 su* z mu/ prevail 9 ! out]mo/ portions ( ! nebul1 9 :i* gases ( o!r sub/ances w\ld be liquefi$4 ,ev5 if ! nebul _h an absolute temp]ature ( #ej 7-#bbc ,c471 ! vapor ( ! mo/ volatile ( all ! metals1 m]cury1 w\ld ev5 9 ! saturat$ /ate be pres5t 9 su* a small quantity t a s+le gramme w\ld occupy ! space ( a cube ^: side w\ld correspond to ab\t two ?\s& light-ye>s--t is to say1 to #dej times ! di/ance ( ! e>? f ! ne>e/ fix$ />4 ,"o gramme ( sodium1 likewise a v volatile metal1 & ( a comp>atively high importance 9 ! con/itution ( ! fix$ />s1 w\ld fill ! side ( a cube t w\ld be a ?\s& million times z l>ge4 ,/ill m inconceivable numb]s result = magnesium & iron1 :i* are v frequ5t con/itu5ts ( fix$ />s1 & :i* are less volatile ?an ! j-m5tion$ metals4 ,we ?us recognize ! /rongly selective action ( ! l[ temp]atures ^u all ! sub/ances :i* are less difficult to cond5se ?an helium & hydrog54 ,z we n[ "k t !re is ano!r sub/ance 9 ! nebul1 :i* has be5 designat$ nebulium1 & :i* is *>act]iz$ by two spectral l9es n f\nd 9 any t]re/rial sub/ance1 we mu/ conclude t ?is o!rwise unkn[n elem5t nebulium mu/ be almo/ z difficult to cond5se z hydrog5 & helium4 ,its boil+-po9t w probably lie bel[ #ej absolute1 l t ( ^? gases4 ,t hydrog5 & helium1 toge!r ) nebulium1 alone seem to occur 9 ! va/ly ext5d$ nebul is probably to be ascrib$ to _! l[ boil+-po9ts4 ,we ne$ n look = any o!r explanation4 ,! supposition ( ,locky] t all ! o!r elem5ts w\ld be trans=m$ into hydrog5 & helium at extreme r>efaction is q unsupport$4 ,9 some:at l[] /rata ( ! nebula1 :]e its %ape resembles a disk1 o!r n easily cond5sable sub/ances1 su* z nitrog51 hydroc>bons ( simple composition1 c>bon monoxide1 fur!r1 at deep] levels1 cyanog5 & c>bon dioxide1 &1 ne> ! c5tre1 sodium1 magnesium1 & ev5 iron may occur 9 ! gase\s /ate4 ,^! less volatile con/itu5ts may exi/ z du/ 9 ! out]mo/ /rata4 ,?is du/ w\ld n be reveal$ to u by ! spectroscope4 ,9 ! /rongly develop$ spiral nebul1 h[ev]1 ! extreme lay]s1 :i* seem to hide ! c5tral body1 appe> to be s att5uat$ t ! du/ float+ 9 !m is n able to obscure ! spectrum ( ! metallic gases4 ,! spectrum ( ! nebula !n resembles a /> spectrum1 because ! deepe/ /rata conta9 inc&esc5t lay]s ( du/ cl\ds1 ^: light is sift$ by ! surr\nd+ masses ( gases4 ,x has be5 obs]v$ t ! l9es ( ! diff]5t elem5ts are n uni=mly di/ribut$ 9 ! nebul4 ,?us ,campbell obs]v$1 = in/ance1 :5 inve/igat+ a small planet>y nebula 9 ! neighborhood ( ! great ,orion nebula1 t ! nebulium _h n ! same di/ribution z ! hydrog54 ,! nebulium1 :i* 0 conc5trat$ 9 ! c5tre ( ! nebula1 probably has a high] boil+-po9t ?an hydrog51 !re=e1 & occurs 9 noticeable quantities 9 ! inn]1 hott] p>ts ( ! nebula4 ,sy/ematic inve/igations ( ?is k9d may help u to a m p]fect k ( ! temp]ature relations 9 ^! peculi> cele/ial objects4 ,ritt] & ,lane h made "s int]e/+ calculations on ! equilibrium 9 a gase\s cele/ial body ( s l[ a d5sity t ! law ( gases may be appli$ to x4 ,t is only p]missive = gases or = mixtures ( gases ^: d5sity does n exce$ "o-t5? ( t ( wat] or "o-f\rte5? ( ! actual d5sity ( ! sun4 ,! pressure 9 ! c5tral portions ( su* a mass ( gas w\ld1 ( c\rse1 be great] ?an ! pressure 9 ! out] portions1 j z ! pressure rises z we p5etrate f above d[nw>d into our t]re/rial atmosph]e4 ,if we imag9e a mass ( ! air ( our atmosph]e transf]r$ "o ?\s& metres high] up1 its volume w increase & its temp]ature w fall by #i4h ,c4 7#ah ,f474 ,if !re 7 extremely viol5t v]tical convection curr5ts 9 ! air1 its temp]ature w\ld dim9i% 9 ?is mann] ) increas+ altitude2 b int]nal radiation t5ds to equalize ^! temp]ature diff]5ces4 ,! foll[+ calculation by ,s*u/] conc]n+ ! conditions ( a mass ( gas ( ! size ( ! sun is bas$ on ,ritt]'s inve/igation4 ,x has be5 made "u ! hypo!sis t ! !rmal prop]ties ( ?is mass ( gas are influ5c$ only by ! movem5ts 9 x1 & n by radiation4 ,! calculation is appli$ to a /> :i* has ! same mass z ! sun 7#a4i #ajcc grammes1 or #cbd1jjj times ! mass ( ! e>?71 & a radius ( ab\t t5 times t ( ! sun 7#aj #fij1jjj km471 ^: mean d5sity w\ld ?us be #ajjj times small] ?an t ( ! sun1 or #j4jjad times ! d5sity ( wat] at #d ,c4 ,9 ! foll[+ table ! fir/ column gives ! di/ance ( a po9t f ! c5tre ( ! /> z a fraction ( its radius2 ! d5sity 7second column7 is express$ 9 ! usual scale1 wat] be+ ! unit2 pressures are /at$ 9 ?\s&s ( atmosph]es1 temp]atures 9 ?\s&s ( degrees ,c5tigrade4 ,! temp]ature w v>y proportionately to ! molecul> weight ( ! gas ( :i* ! /> consi/s2 ! temp]atures1 9 ! f\r? column ( ! table1 conc]n a gas ( molecul> weight #a--t is to say1 hydrog5 gas dissociat$ into atoms1 z x w be und\bt$ly on ! sun & on ! />4 ,if ! /> %\ld consi/ ( iron1 we %\ld h to multiply ^! latt] numb]s by #ef1 ! molecul> weight ( iron2 ! correspond+ figures w be f\nd 9 ! fif? column4 ,temp]ature 9 ,di/ance f ,d5sity ,pressure 9 #ajc #ajc ,c5t4 c5tre atmosph]es ,hydrog5 ,iron #j #j4jjhdd #heb #bdfj #acg1ejj #j4a #j4jjhag #hjg #bdjf #acd1fjj #j4b #j4jjgci #fhc #bbea #abf1ajj #j4c #j4jjfbc #eac #bjjg #aab1djj #j4d #j4jjdhh #cdb #agjg #ie1fjj #j4e #j4jjced #bjj #acgg #gg1ajj #j4f #j4jjbcc #ajj #ajdc #eh1djj #j4g #j4jjacf #dj #gbh #dh1hjj #j4h ,o4#jjjfe #ab #dde #bd1ijj #j4i #j4jjjbj #a4g #bjb #aa1cjj #a4j #j4jjjjj #j #j #j ,s*u/]'s calculation 0 really made = ! sun--t is to say1 = a cele/ial body ^: diamet] is t5 times small]1 & ^: specific gravity is !re=e a ?\s& times great] ?an ! above-assum$ values4 ,accord+ to ! laws ( gravitation & ( gases1 ! pressure mu/ !re be #aj1jjj times great]1 & ! temp]ature t5 times high]1 ?an ^? 9 our table4 ,! d5sity ( ! int]ior portions w\ld1 h[ev]1 become f> too l>ge to admit ( ! application ( ! gas laws4 ,i h !re=e modifi$ ! calculations s z to r5d] !m applicable to a cele/ial body ( t5 times ! radius ( ! sun or ( #ajhj times ! radius ( ! e>?2 ! radius w\ld !n repres5t "o-tw5ty-second ( ! di/ance f ! c5tre ( ! sun to ! e>?'s orbit1 & ! respective cele/ial body w\ld h v small dim5sions inde$ if comp>$ to a nebula4 ,! extraord9>ily high pressure 9 ! int]ior portions ( ! cele/ial body is /rik+2 ?is is due to ! great mass & to ! small di/ances4 ,9 ! c5tre ( ! sun ! pressure w\ld am\nt to #hebj million atmosph]es1 s9ce ! pressure increases inv]sely z ! f\r? p[] ( ! radius4 ,! pressure ne> ! c5tre ( ! sun is1 inde$1 almo/ ( t ord]4 ,if ! sun 7 to exp& to a sph]ical planet>y nebula ( a ?\s& times its actual l9e> dim5sions 7:5 x w\ld almo/ fill ! orbit ( ,jupit]71 ! specific gravity at its c5tre w\ld be dim9i%$ to "o-million? ( ! above-m5tion$ value--t is to say1 matt] 9 ?is nebula w\ld n1 ev5 at ! po9t ( greate/ conc5tration1 be any d5s] ?an 9 ! highly r>efi$ vacuum tubes :i* we c prep>e at ord9>y temp]atures4 ,! pressure w\ld likewise be greatly dim9i%$--namely1 to ab\t six millimetres only1 ne> ! c5tre ( ! gase\s mass4 ,! temp]ature1 h[ev]1 w\ld be r high ne> ! c5tre--namely1 #bd1fjj ,c41 if ! nebula %\ld consi/ ( atomatic hydrog51 & fifty-six times z high aga9 if consi/+ ( iron gas4 ,su* a nebula w\ld re/ra9 gases ) #a4fc times ! =ce :i* ! e>? ex]ts4 ,molecules ( gases mov+ outw>d ) a velocity ( ab\t #ah km4 7#aa miles7 p] second w\ld =ev] dep>t f ?is atmosph]e4 ,! e/imation ( ! temp]ature 9 su* masses ( gases is c]ta9ly some:at unreliable4 ,we h to presume t nei!r radiation nor conduction ex]t any consid]able influ5ce4 ,t might be p]mitt$ = conduction2 b we are h>dly ju/ifi$ 9 neglect+ radiation4 ,! temp]atures )9 ! int]ior ( ! nebula w1 !re=e1 be l[] ?an our calculat$ values4 ,x is1 h[ev]1 difficult to make any def9ite all[ance = ?is factor4 ,if ! mass ( ! cele/ial body %\ld n be z presum$--= in/ance1 twice z l>ge--we %\ld only h to alt] ! pressure & ! d5sity ( ea* lay] 9 ! same proportion1 & ?us to d\ble ! above values4 ,! temp]ature w\ld rema9 un*ang$4 ,we are h5ce 9 a position to picture to ourselves ! /ate ( a nebula ( :atev] dim5sions & mass4 ,lane has prov$1 :at ! above calculations also indicate1 t ! temp]ature ( su* nebula w rise :5 x contracts 9 consequ5ce ( its los+ heat4 ,if heat 7 introduc$ f outside1 ! nebula w\ld exp& "u cool+4 ,a nebula ( ?is k9d presumably loses heat & gradually raises its own temp]ature until x has *ang$ into a />1 :i* w at fir/ h an atmosph]e ( helium & ( hydrog5 l t ( ! y\nge/ />s 7) :ite light74 ,by-&-by1 "u a fur!r rise ( temp]ature1 ! extremely en]getic *emical comp\nds w be =m$ :i* *>act]ize ! int]ior ( ! sun1 because helium & hydrog5--:i* 7 lib]at$ :5 ! nebula 0 re-=m$ & :i* da%$ out into space--w diffuse back into ! int]ior ( ! />1 :]e !y w be b\nd "u ! =mation ( ! comp\nds m5tion$4 ,! atmosph]e ( hydrog5 & ( helium w disappe> 7helium fir/71 ! /> w contract m & m1 & ! pressure & ! convection curr5ts 9 ! gases w become enorm\s4 ,!re w be a /rong =mation ( cl\ds 9 ! atmosph]e ( ! />1 :i* w gradually become end[$ ) ! prop]ties :i* *>act]ize our sun4 ,! sun behaves v diff]5tly f ! gase\s nebul = :i* ! calculations ( ,lane1 ,ritt]1 & ,s*u/] hold4 ,= :5 ! contraction ( a gas %all h proce$$ to a c]ta9 limit1 ! pressure w increase 9 ! ratio #a3 #af1 :ile ! volume w decrease 9 ! ratio #h3 #a1 provid$ !re be no *ange 9 ! temp]ature4 ,:5 ! gas has rea*$ ?is po9t & is /ill fur!r compress$1 ! temp]ature w rema9 9 /eady equilibrium4 ,at /ill high] pressures1 h[ev]1 ! temp]ature mu/ fall if equilibrium is to be ma9ta9$4 ,accord+ to ,amagat1 ?is w occur at #ag ,c4 7#bij absolute7 9 gases l hydrog5 & nitrog51 :i* at ?is temp]ature are f> above _! critical po9ts1 & at a pressure ( #cjj or #bej atmosph]es4 ,:5 ! temp]ature is twice z high on ! absolute scale1 or at #cjg ,c41 twice ! pressure w be requir$4 ,we c n[ calculate :5 our nebula w pass ?r\gh ?is critical /age1 to :i* a l[]+ ( ! temp]ature mu/ succe$4 ,accept+ ! above figures1 we f9d t half ! mass ( ! nebula w fill a sph]e ( a radius #j4ec ( t ( ! nebula4 ,if ! mass 7 ev]y:]e ( ! same d5sity1 half ( x w\ld fill a sph]e ( #j4hd ( ?is radius4 ,:5 w ! int]ior mass cross ! b\nd>y ( ! above /age1 :ile ! ext]ior portions /ill rema9 bel[ ?is /age8 ,t w be at ab\t ! "t :5 ! nebula 9 its totality w pass ?r\gh its maximum temp]ature4 ,we w n[ base our calculations on ! temp]atures :i* apply to iron 9 ! gase\s /ate2 = 9 ! int]ior ( ! nebula ! mean molecul> weight w at lea/ be #ef 7t ( iron74 ,we %all f9d t ! pressure at ! di/ance #j4ec w be ab\t #agg1jjj atmosph]es1 & ! temp]ature approximately #ga million degrees--i4e41 #bde1jjj times high] ?an ! absolute temp]ature 9 ! exp]im5ts ( ,amagat4 ,! specifi$ /age w !n be rea*$ :5 ! pressure w be #bde1jjj times z l>ge z #bej atmosph]es--viz41 #fa million atmosph]es4 ,z1 n[1 ! pressure is only #agg1jjj atmosph]es1 our nebula w yet be f> remov$ f t /age at :i* cool+ w set 94 ,we c easily calculate t ?is w take place :5 ! nebula has contract$ to a volume ab\t ?ree times t ( our sun4 ,! ass]tion :i* is s (t5 made t ! sun might possibly atta9 high] temp]atures 9 ! future is unw>rant$4 ,?is cele/ial body has long s9ce pass$ ?r\gh ! culm9at+-po9t ( its !rmal evolution1 & is n[ cool+4 ,z ! temp]atures :i* ,s*u/] d$uc$ 7 no d\bt mu* too high1 ! cool+ mu/1 inde$1 h set 9 already 9 an e>li] /age4 ,b />s l ,sirius1 ^: d5sity is probably n m ?an "o p] c5t1 ( ! sol> d5sity1 are probably /ill 9 a ris+-temp]ature /age4 ,_! condition approximates t ( ! mass ( gas ( our example4 ,! planet>y nebul are va/ly m volum9\s4 ,! imm5se space :i* ^! cele/ial bodies may occupy w be und]/ood f ! fact t ! l>ge/ among !m1 ,no4 #e 9 ,h]s*el's catalogue1 situat$ ne> ! /> ,b 9 ! ,great ,be>1 has a diamet] ( #b4fg seconds ( arc4 ,if x 7 z ne> to u z our ne>e/ /> neighbor1 its diamet] w\ld yet be m ?an ?ree times t ( ! orbit ( ,neptune2 d\btless x is _m hundr$s ( times l>g]4 ,?is consid]ation furni%es u ) an idea ( ! inf9ite att5uation 9 su* /ructures4 ,9 _! v d5se/ portions ! d5sity _c be m ?an "o-billion? ( ! d5sity ( ! air4 ,9 ! out] portions ( su* nebul ! temp]ature mu/ also be exce$+ly l[2 else ! p>ticles ( ! nebula c\ld n be kept toge!r1 & only hydrog5 & helium c occur 9 !m 9 ! gase\s /ate4 ,yet we may reg>d ! d5sity & temp]ature ( su* cele/ial bodies z gigantic by comp>ison ) ^? ( ! gases 9 ! spirals ( ! nebul4 ,!re nev] is equilibrium 9 ^! spirals1 & x is only because ! =ces 9 action are s extraord9>ily small t ^! /ructures c reta9 _! %apes = long p]iods )\t noticeable *anges4 ,x is1 probably1 *iefly 9 ^? p>ts 9 :i* ! cosmical du/ is /opp$ 9 its motion t meteorites & comets are produc$4 ,! du/ p>ticles w&] into ! m c5tral portions ( ! nebul1 into :i* !y p5etrate deeply1 ow+ to _! relatively l>ge mass1 to =m ! nuclei = ! gr[? ( planets & moons4 ,by _! collisions ) ! masses ( gases :i* !y enc\nt]1 !y gradually assume a circul> movem5t ab\t ! axis ( rotation ( ! nebula4 ,9 ?is rotation !y cond5se portions ( ! gases on _! surface1 & h5ce acquire a high temp]ature--:i* !y soon lose aga91 h[ev]1 ow+ to ! comp>atively rapid radiation4 ,s f> z we "k1 spiral nebul are *>act]iz$ by cont9u\s spectra4 ,! spl5dor ( ! />s )9 !m completely out%9es ! feeble lum9osity ( ! nebula4 ,! />s 9 !m are cond5sation products & und\bt$ly 9 an e>ly /age ( _! exi/5ce2 !y may !re=e be lik5$ to ! :ite />s1 l ! new /> 9 ,p]seus & ! c5tral /> 9 ! r+ nebula ( ! ,lyre4 ,nev]!less1 x has be5 asc]ta9$ t ! spectrum ( ! ,&rom$a nebula has ab\t ! same l5g? z t ( ! yell[ />s4 ,t may be due to ! fact t ! light ( ! />s 9 ?is nebula1 :i* we only seem to see f ! side1 is p>tly ext+ui%$ by du/ p>ticles 9 its out] portion1 z 0 ! case ) ! light ( ! new /> 9 ,p]seus dur+ ! p]iod ( its v>iability4 ,our consid]ations lead to ! conclusion t !re is rotat+ ab\t ! c5tral body ( ! nebula an imm5se mass ( gas1 & t outside ?is mass !re are o!r c5tres ( cond5sation mov+ ab\t ! c5tral body toge!r ) ! masses ( gas conc5trat$ ab\t !m4 ,ow+ to ! friction betwe5 ! immigrat$ masses & ! orig9al mass ( gas :i* circulat$ 9 ! equatorial plane ( ! c5tral body1 all ^! masses w keep ne> ! equatorial plane1 :i* w !re=e deviate little f ! ecliptic4 ,we ?us obta9 a prop] planet>y sy/em1 9 :i* ! planets are surr\nd$ by colossal sph]es ( gas l ! />s 9 ! ,pleiades 7,fig4 #eb74 ,if1 n[1 ! planets h v small mass by comp>ison ) ! c5tral body--z 9 our sol> sy/em--!y w be cool$ at an inf9itely fa/] rate ?an ! sun4 ,! gase\s masses w soon %r9k1 & ! p]iods ( rotation w be %ort5$2 b = ^? planets1 at lea/1 :i* are situat$ ne> ! c5tre1 ^! p]iods w orig9ally diff] little f ! rotation ( ! c5tral body4 ,! dim5sions ( ! c5tral body w always be v l>ge1 & ! planets circulat+ ab\t x w produce v /rong tidal effects 9 its mass4 ,its p]iod ( rotation w be %ort5$1 :ile ! orbital rotation ( ! planets w t5d to become l5g!n$4 ,?us ! equilibrium is di/urb$2 x is re-e/abli%$ aga91 because ! planet is1 s to say1 lift$ away f ! sun1 z ,g4 ,h4 ,d>w9 has s +5i\sly %[n ) reg>d to ! moon & ! e>?4 ,simil> relations w prevail 9 ! neighborhood ( ^? planets :i* w ?us become provid$ ) moons4 ,h5ce we und]/& ! peculi> fact t all ! planets move almo/ 9 ! same plane1 ! s-call$ ecliptic1 & 9 approximately circul> orbits2 t !y all move 9 ! same direction1 & t !y h ! same direction ( rotation 9 common ) _! moons & ) ! c5tral body1 ! sun4 ,x is only ! out]mo/ planets1 l ,uranus & ,neptune1 9 ^: cases ! tidal effects 7 n ( mu* consequ5ce1 t =m exceptions to ?is rule4 ,9 explanation ( ^! ph5om5a v>i\s philosoph]s & a/ronom]s h advanc$ a !ory :i* is kn[n z ! ,kant-,laplace !ory1 aft] its mo/ em95t advocates4 ,sugge/ions po9t+ 9 ! same direction we f9d 9 ,sw$5borg 7#agcd74 ,sw$5borg assum$ t our planet>y sy/em _h be5 evolv$ "u ! =mation ( vortices f a k9d ( 8*aos sol>e10 :i* _h acquir$ a m & m en]getic circulat+ motion ab\t ! sun "u ! influ5ce ( int]nal =ces1 possibly ak9 to magnetic =ces4 ,f9ally a r+ _h be5 ?r[n (f f ! equator1 & _h sep>at$ into fragm5ts1 out ( :i* ! planets _h be5 =m$4 ,buffon introduc$ gravitation z ! cons]vational pr9ciple4 ,9 an +5i\s essay1 8,=mation des ,plantes0 7#agde71 he sugge/s t ! planets may h be5 =m$ f a 8/ream0 ( matt] :i* 0 eject$ by ! sun :5 a comet ru%$ into x4 ,kant />t$ f an orig9al *aos ( /ation>y du/1 :i* "u ! influ5ce ( gravitation arrang$ itself z a c5tral body1 ) r+s ( du/ turn+ ar\nd x2 ! r+s1 lat] on1 =m$ !mselves into planets4 ,! laws ( me*anics tea*1 h[ev]1 t no rotation c be set up 9 a c5tral body1 :i* is orig9ally /ation>y1 by ! influ5ce ( a c5tral =ce l gravitation4 ,laplace1 !re=e1 assum$ ) ,sw$5borg t ! primeval nebula f :i* our sol> sy/em 0 evolv$ _h be5 rotat+ ab\t ! c5tral axis4 ,accord+ to ,laplace1 r+s l ^? ( ,saturn w\ld split (f1 z su* a sy/em contract$1 & planets & _! moons & r+s w\ld aft]w>ds be =m$ out ( ^? r+s4 ,x is g5]ally believ$ at pres5t1 h[ev]1 t only meteorites & small planets1 b n ! l>g] planets1 c\ld h orig9at$ 9 ?is way4 ,we h1 inde$1 su* r+s ( du/ rotat+ ab\t ,saturn1 ! inn]mo/ m rapidly1 ! out] r+s m sl[ly1 j z !y w\ld if !y 7 cr[ds ( little moons4 ,_m fur!r objections h lat] be5 rais$ aga9/ ! hypo!sis ( ,laplace1 fir/ by ,bab9et1 lat] especially by ,m\lton & ,*amb]l94 ,9 its orig9al %ape ?is hypo!sis w\ld c]ta9ly n appe> to be t5able4 ,i h !re=e replac$ x by ! evolution !sis outl9$ above4 ,x is r /rik+ t ! moons ( ! out]mo/ planets1 ,neptune & ,uranus1 d n move 9 ! plane ( ! ecliptic1 & t _! moons fur!r describe a 8retrograde0 movem5t--t is to say1 !y move 9 ! direction opposite to t con=m+ to ! !ory ( ,laplace4 ,! same seems to hold = ! moon ( ,saturn1 :i* 0 discov]$ 9 #ahih by ,pick]+4 ,all ^! facts 71 ( c\rse1 unkn[n to ,laplace 9 #aggf2 & if he _h kn[n !m he w\ld sc>cely h advanc$ 8 !sis 9 ! g>b 9 :i* he (f]$ x4 ,! explanation ( ^! facts does n cause any difficulty4 ,we may assume t ! matt] 9 ! out] portions ( ! primeval nebula 0 s /rongly att5uat$ t ! immigrat+ planet did n atta9 a suffici5t volume to h ! l>ge common rotation 9 ! equatorial plane ( ! sun impress$ ^u x by ! tidal effects4 ,*>g$ only ) ! small mass ( matt] :i* !y met on _! road1 ! planet & its moon1 on ! contr>y1 rema9$ victori\s 9 ! limit$ di/ricts 9 :i* !y 7 rotat+4 ,only ! sl[ orbital movem5t ab\t ! c5tral body 0 influ5c$1 & t adapt$ itself to ! common direction & ! circul> orbit4 ,x is n inconceivable t !re may be1 f>!r out 9 space1 planets ( our sol> sy/em1 unkn[n to u1 mov+ 9 irregul> pa?s l ! comets4 ,! comets1 ,laplace assum$1 probably immigrat$ at a lat] p]iod into our sol> sy/em :5 ! cond5sation _h already advanc$ s f> t ! *ief mass ( ! nebul> matt] _h disappe>$ f int]planet>y space4 ,*amb]l9 & ,m\lton h attempt$ to %[ t ! difficulties ( ! hypo!sis ( ,laplace may be obviat$ by ! assumption t ! sol> sy/em has evolv$ f a spiral nebula1 into :i* /range bodies intrud$ :i* cond5s$ ! nebul> mass ( _! surr\nd+s ^u !mselves4 ,we h po9t$ out examples ( h[ ! nebula seems to vani% 9 ! vic9ity ( ! />s1 :i* w\ld correspond to gr[+ planets1 locat$ 9 nebul4 ,9 conclud+ ?is consid]ation1 we may draw a comp>ison betwe5 ! views :i* 7 /ill ent]ta9$ a %ort "t ago & ! views & prospects :i* ! discov]ies ( mod]n days op5 to our eyes4 ,up to ! beg9n+ ( ?is c5tury ! gravitation ( ,newton seem$ to rule supreme ov] ! motions & ov] ! developm5t ( ! mat]ial univ]se4 ,by virtue ( ?is gravitation ! cele/ial bodies %\ld t5d to draw toge!r1 to unite 9 ev]-gr[+ masses4 ,9 ! inf9ite space ( pa/ "t ! evolution %\ld h proce$$ s f> t "s l>ge suns1 bright or ext9ct1 c\ld alone p]si/4 ,all life w\ld be impossible "u su* conditions4 ,& yet we disc]n 9 ! neighborhood ( ! sun q a numb] ( d>k bodies1 our planets1 & we may surmise t simil> d>k companions or satellites exi/ 9 ! vic9ity ( o!r suns & />s2 = we c\ld n und]/& ! peculi> to-&-fro motions ( ^? />s on any o!r view4 ,we fur!r obs]ve t q a numb] ( small cele/ial bodies ru% ?r\gh space 9 ! %apes ( meteorites or %oot+-/>s :i* mu/ h come to u f ! mo/ remote portions ( ! univ]se4 ,! explanation ( ^! app>5t deviations f :at we may reg>d z a necess>y consequ5ce ( ! exclusive action ( gravity w be f\nd "u two heads--9 ! action ( ! me*anical radiation pressure ( light1 & 9 ! collisions betwe5 cele/ial bodies4 ,! latt] produce enorm\s vortices ( gases ab\t nebul> /ructures 9 ! gase\s condition2 ! radiation pressure c>ries cosmical du/ into ! vortices1 & ! du/ collects into meteorites & comets & =ms1 toge!r ) ! cond5sation products ( ! gase\s envelope1 ! planets & ! moons accompany+ !m4 ,! scatt]+ influ5ce ( ! radiation pressure !re=e balances ! t5d5cy ( gravitation to conc5trate matt]4 ,! vortices ( gases 9 ! nebul only s]ve to fix ! position ( ! du/1 :i* is eject$ f ! suns ?r\gh ! action ( ! radiation pressure4 ,! masses ( gas )9 ! nebul =m ! mo/ important c5tres ( conc5tration ( ! du/ :i* is eject$ f ! sun & />s4 ,if ! _w 7 limit$1 z p us$ to fancy--t is to say1 if ! />s 7 cr[d$ toge!r 9 a huge heap1 & only inf9ite1 empty space outside ( ?is heap1 ! du/ p>ticles eject$ f ! suns dur+ pa/ ages by ! action ( ! radiat+ pressure w\ld h be5 lo/ 9 inf9ite space1 j z we imag9$ t ! radiat$ en]gy ( ! sun 0 lo/4 ,if t 7 s1 ! developm5t ( ! univ]se w\ld long s9ce h come to an end1 to an annihilation ( all matt] & ( all en]gy4 ,h]b]t ,sp5c]1 among o!rs1 has expla9$ h[ ?or\ghly unsatisfactory ?is view is4 ,!re mu/ be cycles 9 ! evolution ( ! univ]se1 he has emphasiz$4 ,t is manife/ly indisp5sable if ! sy/em is to la/4 ,9 ! m r>efi$1 gase\s1 cold portions ( ! nebul we f9d t "p ( ! ma*9]y ( ! univ]se :i* *ecks ! wa/e ( matt] &1 /ill m1 ! wa/e ( =ce f ! suns4 ,! immigrat+ du/ p>ticles h absorb$ ! radiation ( ! sun & imp>t _! heat to ! sep>ate p>ticles ( ! gases ) :i* !y collide4 ,! total mass ( gas exp&s1 ow+ to ?is absorption ( heat1 & cools 9 consequ5ce4 ,! mo/ en]getic molecules travel away1 & are replac$ by new p>ticles com+ f ! inn] portions ( ! nebul1 :i* are 9 _! turn cool$ by expansion4 ,?us e ray emitt$ by a sun is absorb$1 & its en]gy is transf]r$1 ?r\gh ! gase\s p>ticles ( ! nebul1 to suns t are be+ =m$ & :i* are 9 ! neighborhood ( ! nebula or 9 its int]ior portions4 ,! heat is h5ce conc5trat$ ab\t c5tres ( attraction t h drift$ into ! nebula or ab\t ! remnants ( ! cele/ial bodies :i* once collid$ !re4 ,?anks to ! l[ temp]ature ( ! nebula1 ! matt] c aga9 accumulate1 :ile ! radiation pressure1 z ,poynt+ has %[n1 w suffice to keep bodies ap>t if _! temp]ature is #ae ,c41 _! diamet] #c4d cm41 & _! specific gravity z l>ge z t ( ! e>?1 #e4e4 ,at ! di/ance ( ! orbit ( ,neptune1 :]e ! temp]ature is ab\t #ej absolute & approximates1 !re=e1 t ( a nebula1 ?is limit ( size is r$uc$ to ne>ly "o millimetre4 ,x has already be5 sugge/$ 7comp>e page #aec7 t capill>y =ces1 :i* w\ld prevail "u ! co-op]ation ( ! gases cond5s$ ^u ! du/ gra9s1 r ?an gravity1 play a *ief "p 9 ! accumulation & coalesc5ce ( ! small p>ticles4 ,9 ! same mann] z matt] is conc5trat$ ab\t c5tres ( attraction en]gy may be accumulat$ !re 9 contradiction to ! law ( ! con/ant increase ( entropy4 ,dur+ ?is cons]vational activity ! lay]s ( gas are rapidly r>efi$1 to be replac$ by new masses f ! inn] p>ts ( ! nebula1 until ?is c5tre is deplet$1 & ! nebula has be5 conv]t$ into a /> clu/] or a planet>y sy/em :i* circulates ab\t "o or sev]al suns4 ,:5 ! suns collide once m new nebul are creat$4 ,! explosive sub/ances1 consi/+ probably ( hydrog5 & helium 7& possibly ( nebulium71 9 comb9ation ) c>bon & metals1 play a *ief "p 9 ! evolution f ! nebul> to ! /ell> /ate1 & 9 ! =mation ( new nebul aft] collisions betwe5 two d>k or bright cele/ial bodies4 ,! *ief laws ( !rmodynamics lead to ! assumption t ^! explosive sub/ances are =m$ dur+ ! evolution ( ! suns & are de/roy$ dur+ _! collisions4 ,! enorm\s /ores ( en]gy conc5trat$ 9 ^! bodies p]=m1 9 a c]ta9 s5se1 ! duty ( p[]fully act+ fly-:eels int]pos$ 9 ! ma*9]y ( ! univ]se 9 ord] to regulate its movem5ts & to make c]ta9 t ! cyclic transition f ! nebul> to ! /> /age1 & vice v]sa1 w occur 9 a regul> rhy?m dur+ ! immeasurable epo*s :i* we mu/ conc$e = ! evolution ( ! univ]se4 ,by virtue ( ?is comp5sat+ co-op]ation ( gravity & ( ! radiation pressure ( light1 z well z ( temp]ature equalization & heat conc5tration1 ! evolution ( ! _w c cont9ue 9 an et]nal cycle1 9 :i* !re is nei!r beg9n+ nor end1 & 9 :i* life may exi/ & cont9ue =ev] & undim9i%$4 ,,viii ,,! ,,spread+ ,,( ,,life ,,?r\gh ,,! ,,univ]se ,we h j recogniz$ ! probability ( ! assumption t sol> sy/ems h be5 evolv$ f nebul1 & t nebul are produc$ by ! collision ( suns4 ,we likewise consid] x probable t !re circulate ab\t ! newly =m$ suns small] cele/ial bodies :i* cool m rapidly ?an ! c5tral sun4 ,:5 ^! satellites h provid$ !mselves ) a solid cru/1 :i* w p>tly be cov]$ by wat]1 !y may1 "u favorable conditions1 h>bor organic life1 z ! e>? & probably also ,v5us & ,m>s d4 ,! satellites w\ld !reby ga9 a great] int]e/ = u ?an if we _h to imag9e !m z consi/+ entirely ( lifeless matt]4 ,! "q naturally arises :e!r we may believe t life c really orig9ate on a cele/ial body z soon z circum/ances are favorable = its evolution & propagation4 ,?is "q w occupy u 9 ?is la/ *apt]4 ,m5 h be5 pond]+ ov] ^! problems s9ce ! remote/ ages4 ,all liv+ be+s1 pa/ ages recogniz$1 mu/ h be5 g5]at$ & !y _h to die aft] a c]ta9 %ort] or long] life4 ,some:at lat]1 & yet /ill 9 a v e>ly epo*1 exp]i5ce mu/ h taught m5 t organisms ( "o k9d c only g5]ate o!r organisms ( ! same k9d2 t ! species are inv>iable1 z we n[ express x4 ,! idea 0 t all species orig9ally came f ! h&s ( ! ,creator end[$ ) _! pres5t qualities4 ,?is view may /ill be said to repres5t ! g5]al or 8or?odox0 doctr9e4 ,?is view has also be5 call$ ! ,l9nan !sis1 because ,l9n1 9 ! fif? edition ( 8 ,g5]a ,plant>um1 adh]es to x /rictly3 8,species tot sunt1 quot div]sas =mas ab initio produxit ,inf9itum ,ens1 quae de9de =mae secundum g5]ationis inditas leges produx]e plures1 at sibi semp] similes1 ut species nunc nobis non s9t plures quam fu]unt ab initio40 ,:i* we may r5d]3 8,!re are z _m diff]5t k9d ( species z ! ,inf9ite ,be+ has creat$ diff]5t =ms 9 ! beg9n+4 ,^! =ms h lat] eng5d]$ o!r be+s accord+ to ! laws ( inh]itance1 always resembl+ !m1 s t we h at ! pres5t "t n any m species ?an !re 7 f ! beg9n+40 ,"t 0 ripe1 h[ev]1 ev5 !n = a less rigid conception ( nature1 m 9 accordance ) our pres5t views4 ,! fir/ f\ndations ( ! !ory ( evolution 9 ! biological sci5ces 7 laid by ,lam>ck 79 #agid71 ,treviranus 79 #ahji71 ,goe! & ,ok5 79 #ahbj74 ,b a reaction set 94 ,cuvi] & 8 au?ority =c$ public op9ion back to ! anci5t /&-po9t4 ,9 8 view ! n[ ext9ct species ( pa/ geological epo*s _h be5 de/roy$ by natural revolutions1 & new species _h aga9 be5 g5]at$ by a new act ( ! ,creator4 ,)9 ! la/ few decades1 h[ev]1 ! g5]al belief has rapidly be5 revolutioniz$1 & ! !ory ( evolution1 especially s9ce ! immortal ,*>les ,d>w9 came =? ) 8 epo*-mak+ rese>*es1 n[ meets ) univ]sal acceptance4 ,accord+ to ?is !ory ! species adapt !mselves 9 ! c\rse ( "t to _! surr\nd+s1 & ! *anges may become s great t a new species may be consid]$ to h orig9at$ f an old species4 ,! rese>*es ( ,de ,vries h1 )9 q rec5t times1 fur!r acc5tuat$ ?is view1 s t we n[ conc$e cases to be extant :]e new species spr+ =? f old ones "u our v eyes4 ,?is !sis has become kn[n z ! !ory ( mutation4 ,at ! pres5t "t we accord+ly imag9e t liv+ organisms1 su* z we see ar\nd u1 h all desc5d$ f old] organisms1 r unlike !m1 ( :i* we /ill f9d traces & remnants 9 ! geological /rata :i* h be5 deposit$ dur+ pa/ ages4 ,f ?is /&-po9t all liv+ organisms might possibly h orig9at$ f "o s+le1 mo/ simple organism4 ,h[ t 0 g5]at$ /ill rema9s to be expla9$4 ,! common view1 to :i* ! anci5ts incl9$1 is t ! l[] organisms ne$ n necess>ily h orig9at$ f se$s4 ,x 0 notic$ t "s l[-type organisms1 l>v1 etc41 took rise 9 putrid meat2 ,v]gil describes ?is 9 8 ,georgicas4 ,x 0 n until ! sev5te5? c5tury t ?is belief 0 disprov$ by _m exp]im5ts1 among o!rs by ^? ( ,swamm]dam & ,leuw5hoek4 ,! !sis ( ! s-call$ 8,g5]atio spontanea0 once m blossom$ into new life ^u ! discov]y ( ! s-call$ infusoria1 ! small animal organisms :i* seem to arise spontane\sly 9 infusions & concoctions4 ,spallanzani1 h[ev]1 demon/rat$ 9 #aggg t :5 ! infusions1 & ! vessel conta9+ !m1 z well z ! air above !m1 7 heat$ to a suffici5tly high temp]ature to kill all ! g]ms pres5t1 ! infusions w\ld rema9 /]ile1 & no liv+ organisms c\ld develop 9 !m4 ,to ?is fact we owe our ord9>y me?ods ( mak+ pres]ves4 ,x is true t objections 7 rais$ aga9/ ?is demon/ration4 ,! air1 x 0 object$1 is s *ang$ by heat+ t subsequ5t developm5t ( m9ute organisms is r5d]$ impossible4 ,b ?is la/ objection 0 refut$ by ! *emi/s ,*evreul & ,pa/eur1 z well z by ! physici/ ,tyndall 9 ! sixties & sev5ties ( ! pa/ c5tury4 ,^! sci5ti/s demon/rat$ t no organisms are produc$ 9 air :i* is fre$ f ! smalle/ g]ms by "s o!r means ?an heat+--i4e41 by filtration ?r\gh cotton-wool4 ,! rese>*es ( ,pa/eur1 9 p>ticul>1 & ! me?ods ( /]ilization :i* are bas$ ^u !m & :i* are appli$ e day 9 bact]iological laboratories1 h m & m =c$ ! conviction ^u u t a g]m is indisp5sable = ! orig9ation ( life4 ,& yet em95t sci5ti/s take up ! p5 aga9 & aga9 9 ord] to demon/rate ! possibility ( ! 8,g5]atio spontanea40 ,9 ?is !y d n rely ^u ! safe me?ods ( natural sci5ce1 b !y proce$ on philosophical l9es ( argum5t4 ,life1 !y sugge/1 mu/ once h _h a beg9n+1 & we are h5ce =c$ to believe t spontane\s g5]ation1 ev5 if n realizable "u actual conditions1 mu/ h once occurr$4 ,consid]able int]e/ 0 excit$ :5 ! great ,engli% physiologi/ ,huxley believ$ he _h discov]$ 9 ! mud br\ght up f ! v bottom ( ! sea an album9oid sub/ance :i* he call$ 8,ba?ybius ,haeckelii10 9 honor ( ! zeal\s ,g]man ,d>w9i/ ,haeckel4 ,9 ?is ba?ybius 7deep-sea organism7 "o fanci$ = a "t t ! primordial ooze1 :i* _h orig9at$ f inorganic matt] & f :i* all organisms might h be5 evolv$1 & ( :i* ,ok5 _h be5 dream+1 _h be5 discov]$4 ,b ! m exact rese>*es ( ! *emi/ ,bu*anan demon/rat$ t ! album9oid sub/ance 9 ?is primordial ooze consi/$ ( flocks ( gypsum precipitat$ by alcohol4 ,p !n _h rec\rse to ! mo/ fanta/ic speculations4 ,life1 x 0 argu$1 might possibly h _h its orig9 9 ! inc&esc5t mass ( ! int]ior ( ! e>?4 ,at high temp]atures organic comp\nds ( cyanog5 & its d]ivatives might be =m$ :i* w\ld be ! c>ri]s ( life 7,pflg]74 ,!re is1 h[ev]1 little ne$ ( our ent]+ into any ( ^! speculations until !y h be5 provid$ ) an exp]im5tal basis4 ,almo/ e ye> ! /atem5t is repeat$ 9 biological lit]ature t we h at la/ succe$$ 9 produc+ life f dead matt]4 ,among ! mo/ rec5t ass]tions ( ?is k9d1 ! discov]y claim$ by ,butl]-,burke has provok$ mu* comm5t4 ,he ass]t$ t he _h succe$$1 ) ! aid ( ! m>vell\s sub/ance radium1 9 in/ill+ life into lifeless matt]--namely1 a solution ( gelat9e4 ,criticism has1 h[ev]1 relegat$ ?is /atem5t1 l all simil> ones1 to ! realm ( fairy tales4 ,we fully %>e ! op9ion :i* ! great natural philosoph] ,"l ,kelv9 has express$ 9 ! foll[+ words3 8,a v anci5t speculation1 /ill clung to by _m naturali/s 7s mu* s t ,i h a *oice ( mod]n t]ms to quote 9 express+ x71 supposes t1 "u meteorological conditions v diff]5t f ! pres5t1 dead matt] may h run toge!r or cry/alliz$ or f]m5t$ into #8g]ms ( life1' or #8organic cells1' or #8protoplasm4' ,b sci5ce br+s a va/ mass ( inductive evid5ce aga9/ ?is hypo!sis ( spontane\s g5]ation4 ,dead matt] _c become liv+ )\t com+ "u ! influ5ce ( matt] previ\sly alive4 ,?is seems to me z sure a tea*+ ( sci5ce z ! law ( gravitation40 ,al?\gh ! latt] v]dict may be a little dogmatic1 x yet demon/rates h[ /rongly _m sci5ti/s feel ! necessity ( f9d+ ano!r way ( solv+ ! problem4 ,! s-call$ !ory ( pansp]mia really %[s a way4 ,accord+ to ?is !ory life-giv+ se$s are drift+ ab\t 9 space4 ,!y enc\nt] ! planets1 & fill _! surfaces ) life z soon z ! necess>y conditions = ! exi/5ce ( organic be+s are e/abli%$4 ,?is view 0 probably =e%ad[$ long ago4 ,def9ite sugge/ions 9 ?is direction we f9d 9 ! writ+s ( ! ,fr5*man ,sales-,guyon de ,montlivault 7#ahba71 :o assum$ t se$s f ! moon _h awak5$ ! fir/ life on ! surface ( ! e>?4 ,! ,g]man physician ,h4 ,e4 ,ri*t] attempt$ to supplem5t ! doctr9e ( ,d>w9 by comb9+ ! conception ( pansp]mia ) x4 ,flamm>ion's book on ! plurality ( inhabit$ worlds sugge/$ to ,ri*t] ! idea t se$s _h come f "s o!r inhabit$ _w to our e>?4 ,he emphasizes ! fact t c>bon has be5 f\nd 9 meteorites :i* move 9 orbits simil> to ^? ( ! comets :i* w&] ab\t 9 space2 & 9 ?is c>bon he sees ! re/s ( organic life4 ,!re is no pro( at all = ?is latt] op9ion4 ,! c>bon f\nd 9 meteorites has nev] exhibit$ any trace ( organic /ructure1 & we may well imag9e ! c>bon--e4g41 t :i* appe>s to occur 9 ! sun--to be ( inorganic orig94 ,/ill m fanta/ic is 8 idea t organisms float+ high 9 our atmosph]e are caught by ! attraction ( meteorites fly+ pa/ our planet1 & are 9 ?is way c>ri$ out into univ]sal space & deposit$ ^u o!r cele/ial bodies4 ,z ! surface ( meteorites becomes inc&esc5t 9 _! flight ?r\gh ! atmosph]e1 any g]ms :i* !y might possibly h caught w\ld be de/roy$2 & if1 9 spite ( t1 a meteorite %\ld become ! conveyor ( live g]ms1 ^? g]ms w\ld be burn$ 9 ! atmosph]e ( ! planet on :i* !y desc5d$4 ,9 "o po9t1 h[ev]1 we mu/ agree ) ,ri*t]4 ,!re is logic 9 8 /atem5t t 8,! inf9ite space is fill$ )1 or 7m correctly7 conta9s1 gr[+1 mature1 & dy+ cele/ial bodies4 ,by mature worlds we und]/& ^? :i* are capable ( su/a9+ organic life4 ,we reg>d ! exi/5ce ( organic life 9 ! univ]se z et]nal4 ,life has always be5 !re2 x has always propagat$ itself 9 ! %ape ( liv+ organisms1 f cells & f individuals compos$ ( cells40 ,man us$ to speculate on ! orig9 ( matt]1 b gave t up :5 exp]i5ce taught him t matt] is inde/ructible & c only be trans=m$4 ,= simil> reasons we nev] inquire into ! orig9 ( ! en]gy ( motion4 ,& we may become accu/om$ to ! idea t life is et]nal1 & h5ce t x is useless to inquire into its orig94 ,! ideas ( ,ri*t] 7 tak5 up aga9 9 a popul> lecture deliv]$ 9 #ahgb by ! fam\s botani/ ,f]d9& ,cohn4 ,! be/-kn[n expression ( op9ion on ! subject1 h[ev]1 is t ( ,sir ,william ,?omson 7lat] ,"l ,kelv97 9 8 presid5tial address to ! ,briti% ,association at ,ed9burgh 9 #ahga3 8,:5 two great masses come into collision 9 space1 x is c]ta9 t a l>ge "p ( ea* is melt$2 b x seems also q c]ta9 t 9 _m cases a l>ge quantity ( dbris mu/ be %ot =? 9 all directions1 mu* ( :i* may h exp]i5c$ no great] viol5ce ?an individual pieces ( rock exp]i5ce 9 a l&slip or 9 bla/+ by gunp[d]4 ,%\ld ! "t :5 ?is e>? comes into collision ) ano!r body1 comp>able 9 dim5sions to itself1 be :5 x is /ill clo!d z at pres5t ) vegetation1 _m great & small fragm5ts c>ry+ se$ & liv+ plants & animals w\ld und\bt$ly be scatt]$ ?r\gh space4 ,h5ce1 & because we all confid5tly believe t !re are at pres5t1 & h be5 f "t immemorial1 _m worlds ( life besides our own1 we mu/ reg>d x z probable 9 ! highe/ degree t !re are c\ntless se$-be>+ meteoric /ones mov+ ab\t ?r\gh space4 ,if at ! pres5t in/ant no life exi/$ ^u ?is e>?1 "o su* /one fall+ ^u x might1 by :at we bl9dly call natural causes1 lead to its becom+ cov]$ ) vegetation4 ,i am fully consci\s ( ! _m objections :i* may be urg$ aga9/ ?is hypo!sis4 ,i w n tax y\r pati5ce fur!r by discuss+ any ( !m on ! pres5t occasion4 ,all ,i ma9ta9 is t ,i believe !m to be all answ]able40 ,un=tunately we _c %>e ,"l ,kelv9's optimism reg>d+ ?is po9t4 ,x is1 9 ! fir/ in/ance1 que/ionable :e!r liv+ be+s w\ld be able to survive ! viol5t impact ( ! collision ( two worlds4 ,we "k1 fur!r1 t ! meteorite 9 its fall t[>ds ! e>? becomes inc&esc5t all ov] its surface1 & any se$s on x w\ld !re=e be depriv$ ( _! g]m9at+ p[]4 ,meteorites1 moreov]1 %[ q a diff]5t composition f t ( ! fragm5ts f ! surface ( ! e>? or a simil> planet4 ,plants develop almo/ exclusively 9 loose soil1 & a lump ( e>? fall+ ?r\gh our atmosph]e w\ld1 no d\bt1 be dis9tegrat$ into a %[] ( small p>ticles by ! resi/ance ( ! atmosph]e4 ,ea* ( ^! p>ticles w\ld by itself fla% up l a %oot+-/>1 & c\ld n rea* ! e>? 9 any o!r %ape ?an t ( burn$ du/4 ,ano!r difficulty is t su* collisions1 :i*1 z we presume1 are responsible = ! fla%+-up ( s-call$ new />s1 are r r>e ph5om5a1 s t little likelihood rema9s ( small se$s be+ transport$ to our e>? 9 ?is mann]4 ,! "q has1 h[ev]1 ent]$ into a f> m favorable /age s9ce ! effects ( radiation h become und]/ood4 ,bodies :i*1 accord+ to ! d$uctions ( ,s*w>zs*ild1 w\ld und]go ! /ronge/ influ5ce ( sol> radiation mu/ h a diamet] ( #j4jjjaf mm41 suppos+ !m to be sph]ical4 ,! fir/ "q is1 !re=e3 are !re any liv+ se$s ( su* extraord9>y m9ut5ess8 ,! reply ( ! botani/ is t ! s-call$ p]man5t spores ( _m bact]ia h a size ( #j4jjjc or #j4jjjb mm41 & !re are1 no d\bt1 mu* small] g]ms :i* our microscopes fail to disclose4 ,?us1 yell[-fev] 9 man1 rabies 9 dogs1 ! foot-&-m\? disease 9 cattle1 & ! s-call$ mosaic disease--common to ! tobacco plant 9 ,ne!rl&i% ,india1 & also obs]v$ 9 o!r c\ntries--are1 no d\bt1 p>asitical diseases2 b ! respective p>asites h n yet be5 discov]$1 presumably because !y are too m9ute to be visible "u ! microscope4#bj ,footnote #bj3 ,mean:ile a l>ge numb] ( organisms :i* are invisible "u ! ord9>y microscope h be5 r5d]$ visible by ! aid ( ! ultra-microscope1 among o!rs ! presumable microbe ( ! foot-&-m\? disease4 ,x is1 !re=e1 v probable t !re are organisms s small t ! radiation pressure ( a sun w\ld pu% !m out into space1 :]e !y might give rise to life on planets1 provid$ !y met ) favorable conditions = _! developm5t4 ,we w1 9 ! fir/ in/ance1 make a r\gh calculation ( :at w\ld happ5 if su* an organism 7 deta*$ f ! e>? & pu%$ out into space by ! radiation pressure ( our sun4 ,! organism w\ld1 fir/ ( all1 h to cross ! orbit ( ,m>s2 !n ! orbits ( ! small] & ( ! out] planets2 &1 hav+ pass$ ! la/ /ation ( our sol> sy/em1 ! orbit ( ,neptune1 x w\ld drift f>!r into inf9ite space t[>ds o!r sol> sy/ems4 ,x is n s difficult to e/imate ! "t :i* ! smalle/ p>ticles w\ld require = ?is j\rney4 ,let _! specific gravity be t ( wat]1 :i* w v fairly correspond to ! facts4 ,! organisms w\ld cross ! orbit ( ,m>s aft] tw5ty days1 ! ,jupit] orbit aft] eighty days1 & ! orbit ( ,neptune aft] f\rte5 mon?s4 ,our ne>e/ sol> sy/em1 ,alpha ,c5tauri1 w\ld be rea*$ 9 n9e ?\s& ye>s4 ,^! calculations h be5 made "u ! supposition t ! radiation pressure is f\r times z /rong z gravitation1 :i* w\ld be ne>ly correct accord+ to ! figures ( ,s*w>zs*ild4#ba ,footnote #ba3 ,! radiation pressure has "h be5 assum$ to be some:at great] ?an on page #ajc1 because ! spores are "h reg>d$ z opaque1 :ile ! drops ( hydroc>bons h be5 reg>d$ z p>tially translucid to lum9\s rays4 ,^! "t int]vals requir$ = ! organisms to rea* ! diff]5t planets ( our sol> sy/em are n too long = ! g]ms 9 "q to pres]ve _! g]m9at+ p[]4 ,! e/imate is m unfavorable 9 ! case ( _! transf]5ce f "o planet>y sy/em to ano!r1 :i* w require ?\s&s ( ye>s4 ,b we %all see fur!r on t ! v l[ temp]ature ( ^? p>ts ( space 7ab\t -#bbj ,c47 w\ld susp5d ! ext9ction ( ! g]m9at+ p[]1 z x arre/s all *emical reactions4 ,z reg>ds ! p]iod dur+ :i* ! g]m9at+ p[] c be pres]v$ at ord9>y temp]ature1 we h be5 told t ! s-call$ 8mummy :eat0 :i* _h be5 f\nd 9 anci5t ,egyptian tombs 0 /ill capable ( g]m9ation4 ,critics1 h[ev]1 h e/abli%$ t ! respective /atem5ts ( ! ,arabs conc]n+ ! s\rces ( t :eat are v d\btful4 ,! ,fr5* sci5ti/ ,baudo9 ass]ts t bact]ia capable ( g]m9ation 7 f\nd 9 a ,roman tomb :i* _h c]ta9ly rema9$ unt\*$ = eighte5 hundr$ ye>s2 b ?is /atem5t is to be receiv$ ) caution4 ,x is c]ta91 h[ev]1 t bo? se$s ( "s high] plants & spores ( c]ta9 bact]ia--e4g41 an?rax--d ma9ta9 _! g]m9at+ p[] = sev]al ye>s 7say1 tw5ty71 & ?us = p]iods :i* are mu* long] ?an ^? we h e/imat$ z necess>y = _! transf]5ce to our planet4 ,on ! road f ! e>? ! g]ms w\ld = ab\t a mon? be expos$ to ! p[]ful light ( ! sun1 & x has be5 demon/rat$ t ! mo/ highly refrangible rays ( ! sun c kill bact]ia & _! spores 9 relatively %ort p]iods4 ,z a rule1 h[ev]1 ^! exp]im5ts h be5 conduct$ 9 su* a mann] t ! spores c\ld g]m9ate on ! moi/ surface on :i* !y 7 deposit$ 7= in/ance1 9 ,m>%all ,w>d's exp]im5ts74 ,t1 h[ev]1 does n at all con=m to ! conditions prevail+ 9 planet>y space4 ,= ,r\x has %[n t an?rax spores1 :i* are readily kill$ by light :5 ! air has access1 rema9 alive :5 ! air is exclud$4 ,"s spores d n suff] f insulation at all4 ,t applies1 = in/ance1 accord+ to ,duclaux1 to ,?yro?rix scab]1 :i* occurs 9 milk & :i* may live = a full mon? "u ! int5se light ( ! sun4 ,all ! botani/s t ,i h be5 able to consult are ( ! op9ion t we c by no means ass]t ) c]ta9ty t spores w\ld be kill$ by ! light rays 9 w&]+ ?r\gh inf9ite space4 ,x may fur!r be argu$ t ! spores1 9 _! j\rney ?r\gh univ]sal space1 w\ld be expos$ dur+ mo/ ( t p]iod to an extreme cold :i* possibly !y might n be able to endure4 ,:5 ! spores h pass$ ! orbit ( ,neptune1 _! temp]ature w h sunk to -#bbj1 & f>!r out x w s9k /ill l[]4 ,9 rec5t ye>s exp]im5ts h be5 made 9 ! ,j5n] ,in/itute1 9 ,london1 ) spores ( bact]ia :i* 7 kept = tw5ty h\rs at a temp]ature ( -#beb 9 liquid hydrog54 ,_! g]m9at+ p[] 0 n de/roy$ !reby4 ,pr(essor ,macfady5 has1 inde$1 gone /ill fur!r4 ,he has demon/rat$ t micro-organisms may be kept 9 liquid air 7at -#bjj7 = six mon?s )\t be+ depriv$ ( _! g]m9at+ p[]4 ,accord+ to :at ,i 0 told on ! occasion ( my la/ visit to ,london1 fur!r exp]im5ts1 cont9u$ = /ill long] p]iods1 h only confirm$ ?is obs]vation4 ,!re is no?+ improbable 9 ! idea t ! g]m9at+ p[] %\ld be pres]v$ at l[] temp]atures = long] p]iods ?an at our ord9>y temp]atures4 ,! loss ( g]m9at+ p[] is no d\bt due to "s *emical process1 & all *emical processes proce$ at sl[] rates at l[] temp]atures ?an !y d at high]4 ,! vital functions are int5sifi$ 9 ! ratio ( #a3 #b4e :5 ! temp]ature is rais$ by #aj ,c4 7#ah ,f474 ,by ! "t t ! spores rea*$ ! orbit ( ,neptune & _! temp]ature _h be5 l[]$ to -#bbj1 _! vital en]gy w\ld1 accord+ to ?is ratio1 react ) "o ?\s& millions less int5sity ?an at #aj4 ,! g]m9at+ p[] ( ! spores w\ld h5ce1 at -#bbj1 dur+ ! p]iod ( ?ree million ye>s1 n be dim9i%$ to any great] degree ?an dur+ "o day at #aj4 ,x is1 !re=e1 n at all unreasonable to ass]t t ! int5se cold ( space w act l a mo/ effective pres]vative ^u ! se$s1 & t !y w 9 consequ5ce be able to endure mu* long] j\rneys ?an we c\ld assume if we judg$ f _! behavior at ord9>y temp]atures4 ,x is simil> ) ! dry+ effect :i* may be s injuri\s to plant life4 ,9 int]planet>y space1 :i* is devoid ( atmosph]e1 absolute dryness prevails4 ,an inve/igation by ,b4 ,s*rb] demon/rates t ! gre5 alga ,pleurococcus vulg>is1 :i* is s common on ! trunks ( trees1 c be kept 9 absolute dryness 7ov] conc5trat$ sulphuric acid 9 a desiccator7 = tw5ty weeks )\t be+ kill$4 ,se$s & spores may la/ /ill long] 9 a dry atmosph]e4 ,n[1 ! t5sion ( wat] vapor decreases 9 ne>ly ! same ratio z ! spe$ ( ! reaction ) l[] temp]atures4 ,! evaporation ( wat]--i4e41 ! dry+ effect--may h5ce1 at a temp]ature ( -#bbj1 n proce$ fur!r 9 ?ree million ye>s ?an x w 9 "o day at #aj4 ,we h ?us sev]al plausible reasons = conclud+ t spores :i* oppose an effective resi/ance to dry+ may well be c>ri$ f "o planet to ano!r & f "o planet>y sy/em to ano!r )\t sacrific+ _! vital en]gy4 ,! de/ructive effect ( light is1 accord+ to ! exp]im5ts ( ,r\x1 no d\bt due to ! fact t ! rays ( light call =? an oxidation by ! int]m$iation ( ! surr\nd+ air4 ,?is possibility is exclud$ 9 int]planet>y space4 ,moreov]1 ! radiation ( ! sun is n9e hundr$ times fa9t] 9 ! orbit ( ,neptune ?an 9 ! orbit ( ! e>?1 & half-way to ! ne>e/ fix$ />1 ,alpha ,c5tauri1 tw5ty million times feebl]4 ,light1 !re=e1 w n d mu* h>m to ! spores dur+ _! transf]5ce4 ,if1 !re=e1 spores ( ! mo/ m9ute organisms c\ld escape f ! e>?1 !y might travel 9 all directions1 & ! :ole univ]se might1 s to say1 be s[n ) !m4 ,b n[ comes ! "q3 h[ c !y escape f ! e>? aga9/ ! effect ( gravitation8 ,corpuscles ( su* small weight w\ld naturally be c>ri$ away by any a]ial curr5t4 ,a small ra9-drop1 #a_/ej mm4 9 diamet]1 falls1 at ord9>y air pressure1 ab\t #d cm4 p] second4 ,we c calculate f ?is obs]vation t a bact]ia spore #j4jjjaf mm4 9 diamet] w\ld only fall #hc m4 9 ! c\rse ( a ye>4 ,x is obvi\s t p>ticles ( ?is m9ut5ess w\ld be swept away by e air curr5t !y met until !y rea*$ ! mo/ dilut$ air ( ! highe/ /rata4 ,an air curr5t ( a velocity ( #b m4 p] second w\ld take !m to a height :]e ! air pressure is only #j4jja mm4--i4e41 to a height ( ab\t #ajj km4 7#fj miles74 ,b ! air curr5ts c nev] pu% ! p>ticle outside ( our atmosph]e4 ,9 ord] to raise ! spores to /ill high] levels we mu/ h rec\rse to o!r =ces1 & we "k t electrical =ces c help u out ( almo/ any difficulty4 ,at heights ( #ajj km4 ! ph5om5a ( ! radiat+ aurora take place4 ,we believe t ! auror are produc$ by ! dis*>ge ( l>ge quantities ( negatively *>g$ du/ com+ f ! sun4 ,if1 !re=e1 ! spore 9 "q %\ld take up negative electricity f ! sol> du/ dur+ an electric dis*>ge1 x may be driv5 out into ! sea ( e!r by ! repulsive *>ges ( ! o!r p>ticles4 ,we suppose1 n[1 t ! electrical *>ges--l matt]--_c be subdivid$ )\t limit4 ,we mu/ f9ally come to a m9imum *>ge1 & ?is *>ge has be5 calculat$ at ab\t #c4e4aj-aj electro/atic units4 ,we c1 )\t difficulty1 calculate ! int5sity ( an electric field capable ( urg+ ! *>g$ spore ( #j4jjjaf mm4 upw>d aga9/ ! =ce ( gravity4 ,! requir$ field-/r5g? is only #bjj volts p] metre4 ,su* fields are (t5 obs]v$ on ! surface ( ! e>? ) a cle> sky1 & !y are1 inde$1 almo/ normal4 ,! electric field ( a region 9 :i* an auroral display takes place is probably mu* m int5se1 & w\ld1 )\t d\bt1 be ( suffici5t int5sity to urge ! small electrically *>g$ spores :i* convection curr5ts _h c>ri$ up to ^! /rata1 f>!r out into space aga9/ ! =ce ( gravity4 ,x is ?us probable t g]ms ( ! l[e/ organisms kn[n to u are cont9ually be+ c>ri$ away f ! e>? & ! o!r planets ^u :i* !y exi/4 ,z se$s 9 g5]al1 s mo/ ( ^! spores1 ?us c>ri$ away1 w no d\bt meet dea? 9 ! cold inf9ite space ( ! univ]se4 ,yet a small numb] ( spores w fall on "s o!r _w1 & may !re be able to spread life if ! conditions be suitable4 ,9 _m cases conditions w n be suitable4 ,occasionally1 h[ev]1 ! spores w fall on favorable soil4 ,x may take "o million or sev]al millions ( ye>s f ! age at :i* a planet c\ld possibly beg9 to su/a9 life to ! "t :5 ! fir/ se$ falls ^u x & g]m9ates1 & :5 organic life is ?us orig9at$4 ,?is p]iod is ( little significance 9 comp>ison ) ! "t dur+ :i* life w aft]w>ds fl\ri% on ! planet4 ,! g]ms :i* 9 ?is way escape f ! planets on :i* _! ance/ors _h f\nd abode1 may ei!r w&] unob/ruct$ ?r\gh space1 or !y may1 z we h indicat$1 rea* out] planets1 or planets mov+ ab\t o!r suns1 or !y may meet ) l>g] p>ticles ( du/ ru%+ t[>ds ! sun4 ,we h spok5 ( ! ,zodiacal ,light & t "p ( x :i* has be5 designat$ ! c\nt]-gl[4 ,?is latt] gl[ is regul>ly se5 9 ! tropics & occasionally 9 t portion ( our heav5s :i* is j opposite ! sun4 ,a/ronom]s ascribe ! c\nt]-gl[ to /reams ( f9e du/ :i* are drawn t[>ds ! sun 7comp>e page #adg74 ,let u assume t a se$ ( ! diamet] ( #j4jjjaf mm4 /rikes aga9/ a gra9 ( du/ :i* is a ?\s& times z l>ge 7#j4jjaf mm4 diamet]71 & atta*es itself to its surface4 ,?is spore w be c>ri$ by ! gra9 ( du/ t[>ds ! sun2 x w cross ! orbits ( ! inn] planets1 & x may desc5d 9 _! atmosph]es4 ,^? gra9s ( du/ d n1 by any means1 require v long spaces ( "t to pass f "o planet>y orbit to ano!r4 ,if we assume t ! spore />ts ) z]o velocity ne> ,neptune 79 :i* case ! se$ might orig9ate f ! moon ( ,neptune2 = ,neptune itself1 l ,uranus1 ,saturn1 & ,jupit]1 is n yet suffici5tly cool$ to su/a9 life71 ! spore w\ld rea* ! orbit ( ,uranus 9 tw5ty-"o ye>s1 & ( ,m]cury 9 tw5ty-n9e ye>s4 ,) ! same initial velocity su* p>ticles w\ld be twelve ye>s 9 pass+ betwe5 ! orbits ( ,uranus & ,saturn1 f\r ye>s betwe5 ,saturn & ,jupit]1 two ye>s betwe5 ,jupit] & ,m>s1 eighty-f\r days betwe5 ,m>s & ! e>?1 =ty days betwe5 ! e>? & ,v5us1 & tw5ty-eight days betwe5 ,v5us & ,m]cury4 ,we see f ^! "t e/imates t ! g]ms1 toge!r ) ! gra9s ( du/ to :i* !y h atta*$ !mselves1 might move t[>ds ! sun ) mu* small] velocity 7f t5 to tw5ty times small]7 )\t our hav+ to fe> any loss ( _! g]m9at+ p[]s dur+ ! transit4 ,9 o!r words1 if ^! se$s adh]e to ! p>ticles1 n9ety or n9ety-five p] c5t4 ( ^: weight is balanc$ by ! radiation pressure1 !y may soon fall into ! atmosph]e ( "s inn] planet ) ! mod]ate velocity ( a few kilometres p] second4 ,x is easy to calculate t if su* a p>ticle %\ld1 9 fall+1 be arre/$ 9 its motion aft] ! fir/ second1 x w\ld yet1 ?anks to ! /rong heat radiation f x1 n be heat$ by m ?an #ajj ,c5t4 7#bab ,f47 above ! temp]ature ( its surr\nd+s4 ,su* a temp]ature c be borne by ! spores ( bact]ia )\t fatal effects = mu* m ?an "o second4 ,aft] ! p>ticles1 toge!r ) ! se$ adh]+ to !m1 h once be5 /opp$1 !y w sl[ly desc5d1 or w be c>ri$ d[n to ! surface ( ! ne>e/ planet by desc5d+ convection curr5ts4 ,9 ?is way life w\ld be transf]r$ f "o po9t ( a planet>y sy/em1 on :i* x _h tak5 root1 to o!r locations 9 ! same planet>y sy/em :i* favor ! developm5t ( life4 ,! se$s n caught by su* p>ticles ( du/ may be tak5 ov] to o!r sol> sy/ems1 & f9ally be /opp$ by ! radiation pressure ( _! suns4 ,!y _c p5etrate any f>!r ?an to spots at :i* ! radiation pressure is z /rong z at _! />t+-po9ts4 ,consequ5tly1 g]ms f ! e>?1 :i* is five times z ne> ! sun z ,jupit]1 c\ld approa* ano!r sun )9 a fif? ( ! di/ance at :i* g]ms f ,jupit] w\ld be /opp$4 ,some:]e ne> ! suns1 :]e ! se$s are arre/$ by ! radiation pressure to be turn$ back into space1 !re w evid5tly be accumulations ( ^! se$s4 ,! planets :i* circulate ar\nd _! suns h !re=e m *ance ( meet+ !m ?an if !y 7 n 9 ! vic9ity ( a sun4 ,! g]ms w h lo/ ! great velocity ) :i* !y w&]$ f "o sol> sy/em to ano!r1 & !y w n be heat$ s greatly 9 fall+ ?r\gh ! atmosph]es ( ! planets :i* !y meet4 ,! se$s :i* are turn$ back into space :5 com+ ne> a sun w !re p]haps meet ) p>ticles ^: weight is some:at great] ?an ! repell+ p[] ( ! radiation pressure4 ,!y w\ld1 !re=e1 turn back to ! suns4 ,l ! g]ms1 & = simil> reasons1 ^! p>ticles w\ld consequ5tly be conc5trat$ ab\t ! sun4 ,! small se$s h1 !re=e1 a comp>atively bett] *ance ( be+ arre/$ be=e _! return to space by contact ) su* p>ticles1 & ( be+ c>ri$ to ! planets ne> t sun4 ,9 ?is mann] life may h be5 transplant$ = et]nal ages f sol> sy/em to sol> sy/em & f planet to planet ( ! same sy/em4 ,b z among ! billions ( gra9s ( poll5 :i* ! w9d c>ries away f a l>ge tree--a fir-tree1 = in/ance--only "o may on an av]age give bir? to a new tree1 ?us ( ! billions1 or p]haps trillions1 ( g]ms :i* ! radiation pressure drives out into space1 only "o may really br+ life to a =eign planet on :i* life _h n yet aris51 & become ! orig9ator ( liv+ be+s on t planet4 ,f9ally1 we p]ceive t1 accord+ to ?is v]sion ( ! !ory ( pansp]mia1 all organic be+s 9 ! :ole univ]se %\ld be relat$ to "o ano!r1 & %\ld consi/ ( cells :i* are built up ( c>bon1 hydrog51 oxyg51 & nitrog54 ,! imag9$ exi/5ce ( liv+ be+s 9 o!r worlds 9 ^: con/itution c>bon is suppos$ to be replac$ by silicon or titanium mu/ be relegat$ to ! realm ( improbability4 ,life on o!r inhabit$ planets has probably develop$ along l9es :i* are closely relat$ to ^? ( our e>?1 & ?is implies ! conclusion t life mu/ always recomm5ce f its v l[e/ type1 j z e individual1 h[ev] highly develop$ x may be1 has by itself pass$ ?r\gh all ! /ages ( evolution f ! s+le cell upw>d4 ,all ^! conclusions are 9 beautiful h>mony ) ! g5]al prop]ties *>act]i/ic ( life on our e>?4 ,x _c be d5i$ t ?is int]pretation ( ! !ory ( pansp]mia is di/+ui%$ by p]fect consi/5cy1 :i* is ! mo/ important crit]ion ( ! probability ( a cosmogonical !ory4 ,!re is little probability1 ?\gh1 ( our ev] be+ able to demon/rate ! correctness ( ?is view by an exam9ation ( se$s fall+ d[n ^u our e>?4 ,= ! numb] ( g]ms :i* rea* u f o!r worlds w be extremely limit$--n m1 p]haps1 ?an a few )9 a ye> all ov] ! e>?'s surface2 & ^?1 moreov]1 w presumably /rongly resemble ! s+le-cell spores ) :i* ! w9ds play 9 our atmosph]e4 ,x w\ld be difficult1 if n impossible1 to prove ! cele/ial orig9 ( any su* g]ms if !y %\ld be f\nd contr>y to our assumption4 ,,! ,,end