INTERNAL CONDITION OF THE EARTH. 315 



even of rough approximation, what the greatest 

 temperature reached in going downward may be. 

 It may be less than 4000 F., or 5000. It may 

 possibly be as much as 8000 or 10,000; but there 

 is a vast difference between five or ten thousand 

 degrees and the one hundred thousand or million 

 degrees, which we frequently find in geological 

 disquisitions, and against which we do not find 

 sufficient argument, or any argument at all, so far 

 as I am aware, in any regular geological teachings, 

 or published papers or books. 



It appears, then, from the considerations that I 

 have brought before you, that we must give up the 

 argument derived from the phenomena of under- 

 ground temperature as to the internal fluidity of 

 the earth. They show that the earth's interior is 

 at a high temperature, but not at any temperature 

 so high as to make general rigidity of the earth's 

 interior impossible or improbable. This being 

 the state of the case, we are forced to look to argu- 

 ments drawn from other sources to decide the 

 question as to solidity or fluidity, arguments such 

 as are supplied to us from the phenomena of 



