64 C. R. VAN HISE 



the transfers of material are of several kinds, but those of 

 vulcanism and those of changing oblateness are the more 

 important. The conclusions reached may therefore be con- 

 sidered as illustrating Chamberlin's method of multiple working 

 hypotheses. 



It is to be noted in conclusion that the argument of the above 

 paper is independent of any theory of the origin of the earth, and 

 of any theory of the condition of its interior, provided it is 

 largely limited in its application to the time since the earth in 

 some way had attained approximately its present mass. Further- 

 more, the contractional and corrugating effects dependent upon 

 changing rotation involve the hypothesis that at one time the 

 earth rotated upon its axis several times more rapidly than at 

 present. If a more rapid rotational period be assumed than that 

 discussed, the resultant effects would be correspondingly greater. 

 But however the earth originated, and whatever the condition of 

 the interior, the considerations offered which should be taken 

 into account in estimates of crustal shortening are applicable. 



C. R. Van Hise. 



