96 



OUTLINES OF GEOLOGY. 



more than one-tenth of a degree of Fahrenheit's thermometer. 

 It has however been maintained, that the phenomena of vol- 

 canic action are due to a shrinking in the crust of the earth, 

 growing out of a diminishing temperature, and the whole 

 quantity ejected by all the active volcanoes is not sufficient 

 to contradict the preceding statement, that the temperature 

 of the earth is now nearly constant. 



203. As the proposition that the original state of the 

 earth was that of igneous fusion is founded upon a well- 

 known and universal physical law, it might, consistently with 

 the strictest rules of inductive reasoning, be made the founda- 

 tion of a theory. Were we to pursue this, we should find 

 it capable of explaining innumerable geological phenomena. 



FINIS. 



