COSMIC PHILOSOPHY 



cess will afterwards take place with the atmos- 

 phere. M. Saemann shows that by the time 

 the earth had reached complete refrigeration, the 

 pores of the rocks would absorb more than one 

 hundred times the amount of all the oceans on 

 the globe, while room would still be left for the 

 retiring atmosphere. Now this state of things, 

 which will no doubt by and by be realized on 

 the earth, would seem to be already realized 

 on the moon. Being forty-nine times smaller 

 than the earth, the moon has cooled with great 

 rapidity, and its geologic epochs have been cor- 

 respondingly short. 1 



After the moon, we are more familiar with the 

 surface of Mars than with that of any other hea- 

 venly body, the position of Venus being very 

 unfavourable for thorough observations. Con- 

 cerning the physical geography and meteoro- 

 logy of Mars, some trustworthy information has 

 been obtained. The distribution of land and 

 sea over his surface is sufficiently obvious to be 

 delineated in maps. He possesses liquid oceans, 

 proved by spectroscopic evidence to consist of 

 water, and his atmosphere is gaseous. That he 



1 It should be added that the rapid cooling of the moon 

 would greatly increase the porosity of its substance. Professor 

 Frankland has shown that ** assuming the solid mass of the 

 moon to contract on cooling at the same rate as granite, its 

 refrigeration through only 180 F. would create cellular space 

 equal to nearly fourteen and a half millions of cubic miles." 

 288 



