PHILOSOPHICAL 
TRANSACTIONS 
OF THE 
ROYAL SOCIETY 
OF 
LONDON. 
FOR THE YEAR MDCCCLXXXIII. 
VOL. 174— PART I. 
LONDON: 
rilESTED BY HARRISON AND SONS, ST. MARTIN’S LANE, W.C., 
|)rintns in (Drbhrarg io fin' Pajcsfg. 
M DCCCLXXXIi I. 
