394 Anniversary Meeting. [Nov. 30, 



biological problems, and has, moreover, opened np many new lines of 

 research of immense interest in relation to economic questions. 



THE DAVY MEDAL 



is awarded in duplicate to J. H. van't Hoff and J. A. Le Bel, in 

 recognition of their important services to theoretical chemistry. 



J. H. van't Hoff was the first to introduce a definite mechanical 

 conception of valency, and to connect the optical chirality displayed 

 by many carbon compounds with their chemical constitution. The 

 fact that such compounds always contain at least one atom of carbon 

 combined in four different ways has now been fully established, and 

 the doctrine of " asymmetric " results from the quadri valence of 

 carbon forms the basis of the modern theory of stereo-isomerism. 



Van't Hoff's first paper upon the subject was published in Sep- 

 tember, 1874, in the Dutch language, but appeared in 1875 under the 

 title " La Chimie dans 1'Espace." 



At that time many compounds were known which seemed to con- 

 stitute exceptions to the new generalisation, but further investigation 

 has shown that these exceptions were only apparent, and are now 

 included in and are explained by the theory. 



A second very important contribution to science resulted from the 

 mathematical investigations of van't Hoff in reference to the pro- 

 perties of liquids and the condition of dissolved solids in dilute 

 solutions. By these investigations he has supplied the theoretical 

 explanation of the phenomena involved in the method of determining 

 molecular weights, which we owe to the experimental investigations of 

 Professor Baoult,and for which he received the Davy Medal last year. 



To M. J. A. Le Bel we owe an independent enunciation of the 

 theory of asymmetric combinations with carbon, published in the 

 * Bull, de la Soc. Chim.' only two months later than the Dutch paper 

 of van't Hoff, that is, in November, 1874. Le Bel has contributed 

 substantially by his work on active amyl alcohol and its derivatives 

 to the support of the theory which, as already stated, is accepted 

 universally by chemists. The justification for what appears at first a 

 purely speculative hypothesis is supplied by the fact that the intro- 

 duction of the new views has led to the discovery of many new 

 carbon compounds the existence of which could not have been pre- 

 viously suspected. 



The Statutes relating to the election of Council and Officers were 

 then read, and Mr. Crookes and Admiral Sir Erasmus Ommanney, 

 having been, with the consent of the Society, nominated Scrutators, 

 the votes of the Fellows present were taken, and the following were 

 declared duly elected as Council and Officers for the ensuing year : 



