is alledged could not happen if there was an atmosphere about her. 

 But let it be remembered that this conclusion will hold good only 

 in the supposition that the matter of which the lunar atmosphere is 

 composed, is like that of ours, that is, decreasing gradually in 

 density from the surface of the body it surrounds, as it recedes 

 from it. But the atmosphere of the moon, which causes the ap- 

 pearance under consideration, is evidently of a uniform density ; 

 for the exterior edge of the luminous girdle was" as strongly and 

 distinctly marked as the interior, and in such case, the conclusion 

 drawn from the instantaneous disappearance of the stars, as before 

 mentioned, is inadmissible. It is carrying analogical reasoning 

 too far to take, as a postulate in this case, that if the moon has an 

 atmosphere, it must be in all respects like ours. From what has 



phere, and that it is of a uniform density. What the matter of it is, 

 whether water, air or something else not belonging to this earth, is 

 immaterial : it is sufficient, for my theory, that it has the property 

 of every other diaphanous medium, through which light passes, to 

 refract its rays. This atmospheric girdle, let it be further remark- 

 ed, was completely distinct, in its colour as well as its bounds, 

 from the luminous streams of phosphoric light emitted from the 

 moon, as observed during the eclipse. It must therefore have 

 been^essentially different in its nature and the cause which pro- 

 There is then no way to account for this dazzling cincture about 

 the moon, but to take thn fhct for granted, or rather proved, that 

 she has an atmosphere, and that it differs from ours in the manner 



Uie exterior edge of this atmosphere, its rays will be so refracted 

 as to become instantly invisible. 



Our atmosphere contains a great variety of heterogenous mat- 

 ter, such as the oxygen, hydrogen and azotic gases. What the 

 atmosphere of the moon contains it is impossible to know ; but it is 

 presumable that it also contains a variety of heterogenous matter, 

 and as nothmg is created in vain, that, like every other thing, 

 must Be .ntended for useful purposes, and considering the moon as 



