PEOCEEDINGS 



OF THE 



CAMBRIDGE PHILOSOPHICAL 

 SOCDETY 



VOL. XX. PART I. 

 [Lent and Easter Terms 1920.] 



CAMBRIDGE 



AT THE UNIVERSITY PRESS 



AND SOLD BI 

 DEIGHTON, BELL & CO., LIMITED. 

 AND BOWES & BOWES, CAMBRIDGE. 



CAMBRIDGE UNIVERSITY PRESS, 



0. F. CLAY, MANAGER 



FETTER LANE , LONDON , E.C. 4 



1920 

 Price Seven Shillings Net 



September 1920. 



