64 



0.0020 



130 



lil eoiu'liisioii it is our pleasani (iiit,y lo thank Miss H. van dkr 

 HoKST and Mr. .1. D. A. Boks for llieir careful legulation of the 

 tempei-atuie, and Mr. L. Ouwkrkkkk and Mr. 0. F. L. Kra,\nkvf.i.d 

 for the techniral skill with which they helped us during the whole 

 course of the ineasuremeiits. 



