ANNIVEKSARY ADDRESS. 35 



attempt to reach general views respecting chemical reactions. 

 A priori, the chemical achievements of this century seemed an 

 impossibility, but success has transcended the most sanguine 

 expectations, and there can be no doubt that in the future the 

 science will play even a still greater part in the world's develop- 

 ment. 



Were it not an intrusion on the solemnity of these proceedings, 

 I might have been permitted to shew that chemistry reacts on 

 the aesthetic faculties of the world. Who, for example, looking 

 at a brilliant social function, graced by the presence of the sex 

 that lends it all its subtle beauty and charm, recognises how much 

 is due to the delicacy and glory of colour which the genius of the 

 chemist has provided ! Perhaps, after all, such recognition were 

 a profanity on such an occasion, and the highest tribute to that 

 genius is the fact that we are overwhelmed with aesthetic pleasure. 



The service of organic chemistry to therapeutics would be diffi- 

 cult to over-estimate. Not only have many natural substances 

 required by physicians been prepared artificially, but the com- 

 prehensive study of the relation of chemical structure to phy- 

 siological and therapeutic activity, has enabled the chemist to 

 predict with some degree of confidence the action of new sub- 

 stances. For example, the hypnotic sulphonal is chemically 

 dimethyl-diethyl-sulphone-methane. The substitution of ethyl 

 for one of the methyls gives trional, and of ethyls for both 

 methyls, tetronal, substances of identical character but with 

 reinforced physiological activity. That inferences of this nature 

 have to be drawn with extreme care, however, is indicated in the 

 quaternary amido-compounds betaine, choline, and neurine, the 

 two first being innocuous while the last is extremely poisonous : — 

 Choline = CH 2 OH • CH 2 - NMe 3 - OH 

 Neurine = CH 2 : CH • NMe 3 - OH 



It is impossible here to give any sufficient idea of the reaction 

 of structural chemistry on physics. One instance will shew some- 

 thing of its significance. To the labours of Briihl, Landolt, Oonrady, 

 KannonikofF, and others, we owe the knowledge that the molecular 



