vi Preface 



ceedings of the Association for the period from 1934 to 1940, the reports of 

 its meetings for these years contain much more information than do those 

 for earlier years. The titles listed include not only those of the addresses of 

 presidents and vice presidents but also all those that were open to the public 

 as general sessions, with references to the places of their publication. The 

 titles of more than two hundred and fifty addresses and papers are given. 

 This volume also contains the titles of all the symposia presented at the 

 twenty-one meetings of the Association and its divisions from 1934 to 1940, 

 a total of more than two hundred at which nearly fourteen hundred papers 

 were read. 



In short, this volume contains sketches of the science of our predecessors 

 and much of that which is recent. Those whose memories reach back a few 

 decades will feel as they read of the youth of the Association a certain 

 nostalgia for simpler days and attitudes that have passed. It is hoped that 

 they will catch enough echoes from the historical part of this record to 

 awaken in them many happy memories and only pleasant anticipations for 

 the future. Those who are in the early parts of their scientific careers will be 

 most interested in current progress in science. They may even be a little 

 amused at what now seem naive ideas that were held in earlier days. Yet it 

 is hoped that for them the historical sections of this book will sometimes 

 serve as a little mirror, like that in the front of a motor car, in which they 

 may catch enough glimpses of the road science has traversed to assist them 

 in steering it wisely into the future. 



Forest Ray Moulton, 

 Permanent Secretary 



