OP BARON HUMBOLDT. 25 



the new world; and his ever clear and quick 

 perception soon recognized an absolute law in 

 the seeming chaos. He became an important 

 labourer in geognosy, the science of the com- 

 position and the formation of the solid crust of 

 the earth ; and here he opened a new avenue, 

 presented a new aspect, dismissing the old 

 theories regarding the causes in the changes 

 of the climatic condition of the earth, which 

 must have been, according to existing testi- 

 monies, quite different many thousand years 

 ago from the present condition, because rem- 

 nants of animals and plants, natives of the 

 south, were exhumed in cold northern regions, 

 which was accounted for by the liberated heat 

 of down-crushed masses of mountains, and 

 similar causes ; he recognized the more im- 

 portant activity of volcanic powers in the bowels 

 of the former earth, and concluded, in a most 

 ingenious manner, the then higher tempera- 

 ture of our planet. His labours in this depart- 

 ment of physical science are of a most im- 

 portant and positive nature, and exercised upon 

 general science a powerful influence ; but as 

 Humboldt never advanced any new opinion 

 without some practical proofs, he brought with 

 him a valuable collection of various kinds of 

 rocks from America, compared them with the 



