57 



''Jirögo «u0 <polar^3?eoba4)tini9eii —56", 7; <peclet —60"; eaiget) 

 burc^ bie 2öarme:'3(bn«I)nie in i>ex "ätmofTßijuxe auö 367 meiner 

 SSeobac^tungeu in ber iMn^e^fette unb in 9)ierico — 65", burd) 

 ^iljermometer^gifeifungen am 5)?ontblanc unb bei ber aerpfratii'cljeu 

 Oteife wn @ap--£u|Tac —77"; <Bix ^ol)n ^erfc^el Edinburgh 

 Review Vol. 87. 1848 p. 2-23) — 132" J., alfo —91" gciU. 

 QBie <poi|Ton, H bie ?0?itret^2emperarur »on g}tetvt[Ie--3nfel (58v. 

 74"47') r*on —18", 7 ifr, für ben 2iseltrrtum ans rein tljecreti: 

 fcf)en ©rünben, wad) benen ber üöelrraum ivarmer alö bie äußere 

 ©renje ber 3irmofv()are fein foll (5 227 p. 520), nur — 13", unb 

 bagegen ''Ponillet md) actiuometrifcfeen 23erfuc^en (Compies ren- 

 dus de l'Acad. des Sc. T. Vil. 1838 p. 23-63) gar -142" 

 finben; mup Söunber nel)men unb in biefen intereiJanten <Bpec\u 

 lationen bae 23ertrauen ju ben biö^er eingefc^Iagenen 2öegen 

 minbern. 



" (S. 47.) ^^oiffon, Theorie malhem.de iaChaleur 

 p. 438. ^Tiad) i()m I^at t)ie ßrljartung ber Srbfc^tdjten von bem 

 Sentrum angefangen, unb ift uon biefem jur £>berr1ad}e allmalig 

 fortgefd)ritten; § 193 p. 429. (äsergl. and) Äoömoö S8b. I. 

 @. 184.) 



^" (®. 48.) .Soömoö 58b. I. ©, 86 unb 149. 



*' (®. 49.) »Were no atmosphere, a thermometer, ireely 

 cxposed (at sunset) lo the heating influence of Ihe earth's radia- 

 lion, and the cooliiig power of ils own into space, would indi- 

 cale a medium temperalure between thal of the celeslial spaccs 

 (—132" Fahr. = — 91° Cent.) and thal of the earth's suriacc 

 below it (82" F. = 27", 7 Cent, al the cquator, —3", 3 F. ^ 

 — 19", 3 Cent, in the Polar Sea). Under ihe equator, Ihen, it 

 would stand, on the average, at —25" F. = — 31", 9 Cent.; 

 and in the Polar Sca at — 68" F. := — 33", 3 Cent. The prc- 

 sencc of the atmosphere tends to prevent the thermometer so 

 exposed from attaining these extreme low temperatures: llrst, 

 by imparting heat by conduction; secondly by impeding radia- 

 tion outwards.« <Str joO" ..^erfd^el im Edinburgh Review 

 V^ol. 87. 1848 p. 223. — «Si la chalear des cspaces planelaircs 

 n'exislait point, notre atmosphere eprouverait un refroidisse- 

 ment, dont on ne peut fixer la liraite. Probablement la vie 

 des plantes et des animaux serait impossible a la surfacc du 



