82 Anmversary Address by Lord Rayleigh. [| Nov. 30, 
indebted to his exceptional skill and judgment in unravelling the mysteries 
of early Vertebrate life. 
Davy MEDAL. 
The Davy Medal is awarded to Professor Edward Willams Morley. 
Professor Edward W. Morley is well known both to chemists and to 
physicists for his work in the application of optical interferences and other 
physical phenomena to increase the accuracy of measurement. Numerous 
valuable papers have appeared, either in collaboration with Professor 
Michelson and others, or in his own name, on such subjects. Special 
reference may be made to his experiments, in conjunction with Professor 
Michelson, on the fundamental question of the absence of effect of translatory 
motion of material bodies on luminous phenomena. 
His claim to the Davy Medal rests on grounds closely related to these 
researches; for he has combined thorough mastery of accurate measurement 
with an intimate knowledge of modern chemistry, and has utilised them in 
his attempt to solve one of the most difficult and fundamental problems of 
chemical science. The special problem to which he has consecrated many 
years of his life is the determination of the relative atomic weights of 
hydrogen and oxygen; it has been attacked by him with rare insight and 
skill, and with indomitable perseverance, and he seems to have settled 
it for many years to come, if not permanently. All the recent work devoted 
to this problem, and there has been much, has tended to establish more 
firmly the ratio arrived at by Professor Morley. 
His determinations of the absolute weights of a litre of hydrogen and of 
oxygen, and his investigations of the amounts of moisture retained by gases 
dried by various desiccating agents, are of the very greatest importance for 
scientific progress. : 
SYLVESTER MEDAL. 
Professor Wilhelm Wirtinger, of Vienna, is the recipient of the Sylvester 
Medal. | 
He is distinguished for the importance and wide scope of his contributions 
to the general Theory of Functions. Our knowledge of the general 
properties and characteristics of functions of any number of independent 
variables, and our ideas for the further investigation of such functions are, 
for the most part, at present bound up with the Theory of Multiply- 
periodic Functions, and this Theory is of as great importance for general 
Solid Geometry as the ideas of Abel have proved to be for the Theory of 
Plane Curves. Professor Wirtinger has applied himself for many years 
to the study of the general problems here involved. A general summary 
