192 



exceeding vagueness of the conceptions of the nature oi the solid 

 state, and the absence of a general point of view, they have not 

 been able to assume such a form as to lead to a satisfactory 

 explanation. ') 



Ancry. Chein. Laboratory of the University. 



Amsterdam, January 1913. 



Chemistry. — '-The nitration of toluols and its derivatives clUorated 

 in the side-chain". By Prof. A. F. Hollfjman. 



(This communication will not be published \\\ these Proceedings). 



1) 11 may be expected that in the near future it will appear possible also in 

 many other cases to demonstrate by tbe use of solvents or chemical reagents the 

 complexity also of tliose substances wliicli have been considered up to now as 

 behaving exclusively as unary substances. 



(September 3, 1913). 



