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astronomical observations, which are not only doubtful, but 

 proved incorrect. It is said that the moon turns on her own 

 axis, because she is an oblate spheroid, notwithstanding that 

 she always presents the same face towards the earth. That a 

 body revolving round a centre, and continuing to present the 

 same face to that centre, should rotate on an axis situated parallel 

 to the revolving axis, is physically impossible. Yet it is main- 

 tained, and absolutely stated in our astronomical works, that the 

 moon rotates on her axis. 



There is another idea propagated respecting this body, viz. 

 that she has no atmosphere, because we do not observe any re- 

 fraction during the occultations of the stars. If the moon is 

 enveloped in an atmosphere, the angle of refraction would be 

 between the moon and the star, and that would, on impinging 

 on the moon's surface, be reflected towards the earth. If a ray 

 of light be successively transmitted through several transparent 

 media having different refracting powers on one side, and re- 

 flected so as to pass through similar media on the other side, 

 its emergence from the last of these media will take a direction 

 parallel to that which it had when incident upon the first of 

 them. In this case the several refractions which the ray suffers 

 in passing through the media on the one side is compensated 

 and neutralised on the other, so as to produce, on the whole, no 

 deflection of the ray from its original course. " The angle of in- 

 cidence is equal to the angle of reflection." The reason why we 

 observe the refraction of the rays in our atmosphere is, because 

 we are exposed to one angle only, i. e. that of refraction, owing 

 to our being within the spherical media. Yet we are told the 

 moon has no atmosphere, because she does not show signs of 

 refraction, notwithstanding the contrary evidences proved by 

 the halo which this body often exhibits. Persons have attempted 

 to describe the geological features of the moon ! If the above 

 simple questions are in such a confused state, and so easily de- 

 monstrated at a distance by the aid of mathematics, what are 

 we to expect from the geology of the moon ? Unless geologists 

 can procure more substantial data than those obtained from celes- 

 tial observations, it is not very probable that the science can im- 

 prove ; and much less when fettered by other incompatible laws, 

 which have taken too deep a root to be very easily eradicated. 



The changes of climate have been attributed by some to a 



