THE 



AMERICAN JOURNAL OF SCIENCE 

 A- 



c?" 



[THIRD SERIES.] 



Art. LIII. — The Temperature of the Moon. From Studies 

 at the Allegheny Observatory by S. P. Lang-ley, with the 

 assistance of F. W. Very. 



(Memoir read to the National Academy of Sciences, November, 1887.) 



This memoir may be regarded as the completion of the 1 

 investigation commenced in 1883, and continued during the 

 next four years, and of which previous portions have been 

 published in the Memoirs of the National Academy of Sci- 

 ences, in a paper read Oct. 17, 1884 (vol. iii), and in that read 

 Nov 9, 1886, (vol. iv), the latter having been published in 

 abstract in the American Journal of Science.* 



The original memoir, of which the following is a very succinct 

 abstract, can, from its special character, hardly claim the atten- 

 tion of the general reader ; but the latter may, perhaps, be 

 here reminded that the main questions at issue are the temper- 

 ature of an airless planet at the earth's distance from the sun, 

 the action of the atmosphere in modifying the temperature of 

 such a planet, and, in general, the study of those conditions of 

 radiation and absorption which have actually rendered life 

 possible on our own. He may be reminded also that it has 

 been generally assumed hitherto that the temperature of the 

 sunlit surface of an airless planet at such a distance, e. g. of the 



* For December, 188S. See also London, Edinburgh and Dublin Philosophical 

 Magazine, December, 1888; also Ann. de Chemie et de Physique, July, 1889. 

 Am. Jour. Sci.— Third Series, Vot.. XXXVIII, No. 228.— Dec, 1889. 

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