PHILOSOPHICAL 
EANSACTION 
OF THE 
ROYAL SOCIETY 
OF 
LONDON. 
FOR THE YEAR MDCCCLXXVIII. 
VOL. 169. 
LONDON : 
PRINTED BY HARRISON AND SONS, ST. MARTINS LANE, W.C., 
gratters in (Drisiitarg to per Utajestg. 
MDCCCLXXIX 
