io6 THEOR Y OF ARISTOTLE. 



square equal surfaces, appeared to him the most perfect 

 geometrical solid, and consequently the most suitable for the 

 earth, supposed to be the centre of the universe. 



Eudoxes, who, in his long travels in Greece and Egypt, 

 must have seen new constellations rising in the south, while 

 others disappeared in the north, never ventured to adduce from 

 his astronomical observations the sphericity of the earth. 



Aristotle, bolder than Eudoxes, was led to the conception 

 of this sphericity by simple consideration of mechanics. The 

 earth, he said, must be a sphere, because each particle of matter 

 is carried, by gravity, towards the centre ; and as this fact is 

 general, the superficial particles must be at an equal distance 

 from the centre. This theoretical view was adopted by Archi- 

 medes, who applied it to the waters covering the terrestrial sur- 

 face. Aristotle went further ; he saw the rotundity of the earth 

 in the shadow thrown by the latter on the bright face of the 

 moon during its eclipses. 



It is a noteworthy fact that the arguments of Aristotle, 

 founded on a method to which all the progress of science is 

 due, remained unaccepted for two thousand >ears. And why? 



We shall attempt to explain. 



Among those subjects whose comprehension seems to have 

 been specially difficult to the mind of man, we must include 

 the fact that the earth floats without any solid support in the 

 infinity of space, and carries its denizens on its surface, both 

 above and below. 



Our creeds, which have ever pretended to explain every- 

 thing in the physical as well as in the moral order, have here 



