PHILO SOP HIC AL 
T It A NSACIIONS 
OF THE 
ROYAL SOCIETY 
LONDON. 
FOR THE YEAR MDCCCLXXIX. 
VOL. 170. 
LONDON* 
PRINTED DY HARRISON AND SONS, ST. MARTINS LANE, W.C., 
Printers in Orbinnrjr to ||er IJlnjcsttr, 
MDCCCLXXX. 
