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 88 KINGSWAY, LONDON, W.C.2 



U.S.A. Edition published by 



ACADEMIC PRESS INC., PUBLISHERS 



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NEW YORK 10, NEW YORK 



September 1954 



This book is Volume VII of the Colston Papers. Permission must be 



obtained from the Colston Research Society, 12 Small Street, Bristol, 



England, and from the Publishers, before any part of the contents 



can be reproduced. 



Previous volumes in the Colston Papers are: 

 Vol. I. 1948 Cosmic Radiation — Editor, Professor F. C. Frank 

 Vol. II. 1949 Engineering Structures — Editor, Professor A. G. 



Pugsley. 

 Vol. III. 1950 Colonial Administration — Editor, Professor C. M. 



Maclnnes. 

 Vol. IV. 1 95 1 The Universities and the Theatre — Editor, Professor 



D. G. James. 



Vol. V. 1952 The Suprarenal Cortex — Editor, Professor J. M. 

 Yoffey. 



Vol. VI. 1953 Insecticides and Colonial Agricultural Development — 

 Editors, Professor T. Wallace and Dr. J. T. 

 Martin. 



There will be no Colston Symposium in 1955, 

 owing to the visit to Bristol of the British 

 Association. The series will be resumed in 1 956. 



Made and Printed in Great Britain by 

 J. W. Arrowsmith Ltd., Bristol 



