PHILOSOPHICAL 
RAN S ACTION 
OF THE 
EOYAL SOCIETY 
OF 
LONDON. 
FOR THE YEAR MDCCCLXXXI1J. 
VOL. 174. 
LONDON: 
PRINTED BY HARRISON AND SONS, ST. MARTINIS LANE, W.C., 
printers in ©rbinnrg to Per Utajestj). 
MDCCCLXXXIV. 
