﻿xlviii Annual Report of the Council. 



etherification, but he also showed the existence of a series of 

 mixed ethers. These researches practically introduced into 

 chemistry the "water-type," a theory which, although now 

 merged in the more comprehensive modern theories of chemical 

 constitution, was, in the hands of Williamson, wonderfully 

 fascinating and fertile. 



The doctrine of types was always the basis of Williamson's 

 teaching. As a lecturer, especially on organic chemistry, he 

 was unexcelled. The writer of this notice will never forget 

 the delight with which he used to listen to Williamson's 

 lectures on organic chemistry. At that time (in the early 

 seventies) it was quite a common thing for the Demonstrators 

 and Assistants in the laboratory, and even the Assistant 

 Professors, to join the students in the Lecture Theatre, to hear 

 once more the master's exposition. 



Williamson occupied many important and honourable 

 positions in connection with the Royal, the Chemical, and 

 other Societies. He was President of the British Association 

 at the Bradford meeting in 1873, an d General Treasurer of that 

 Association from 1874 to 1891. He was elected an honorary 

 member of our Society in 1889. He retired from active work 

 in 1887, living afterwards in such seclusion that he was practi- 

 cally unknown to the younger generation of chemical workers. 



He died at his house at Hindhead, on May 6th, 1904. 



R. L. T. 



The Obituary Notice of Dr. George Wilson could not be 

 prepared in time to be inserted here, and will therefore appear 

 in the next volume. 



