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Xir. On the Quejllon, nvhether the Sun, the Moon, end 

 other heavenly Bodies are furrounded hj Atmofpheres. Bj 



T. W. A. MURHARD*. 



X HIS queftion is of the utmoft importance to the phl- 

 lofopher as well as the aftroiiomer ; and the more fo at the 

 prefent period, as the difpute between the fo-called Atmo- 

 fpherians and Anti-atmofphcrians, which has been conti- 

 nued ever fince the beginning of this century, is not yet 

 ended. It relates in particular to the atmofphere of the 

 moon, which was fo ftrenuoufly maintained by Plutarch. 

 But it would be as ridiculous to refer the conteft to reafon, 

 as if we fliould endeavour to give a decifive opinion refpefting 

 a ciroumftance with which we are totally unacquainted. It 

 is certain that nothing on this point can be determined 

 a priori; and therefore fuch conclufions as are drawn from 

 analogy muft be confidered as decifive. The fenfes muft 

 here be our guide ; but it is much to be lamented, that our 

 organs are often too weak, and our inftrumcnls too imper- 

 feft, notwithftanding the great precifion to which the latter 

 have been carried in modern times. 



But we muft firft endeavour to eftablifh what we mean 

 in general by the term atmo/phere. By atmofphere, I un- 

 derftand that delicate fubtile body which immediately fur- 

 rounds the planets, and which is mixed with thofe heteroge- 

 neous particles diffolved on their furfaces, or which evaporate 

 from them. By this definition it is evident, that, according 

 as the nature of the planet, and the particles diffolved on its 

 mrface, are different, the atmofpheres muft neceffarily be dif- 

 ferent alfo ; fo that, by knowing the phyfical nature of the 

 furface of any of the planets, we can form a conclufion re- 

 fpecting the nature of its atmofphere, and vice verfa. Of this 

 we have a fufficlent number of inftances in regard to the 

 earth. Let us here only compare the pure air of the dry 

 diftrifts of Arabia with the air of marftiy watery diftrifts, 

 which is continually filled with vapours, clouds, and rain, and 

 we fliall foon be convinced of the truth of this pofition. But 



* From Heuei Journal der thjfk, by F. A. C, Gien, Vol. III. part 4. 



7 whether 



