PHILOSOPHICAL 
TRANSACTIONS 
OF THE 
ROYAL SOCIETY OF LONDON, 
Series A. 
CONTAINING PAPERS OF A MATHEMATICAL OR PHYSICAL CHARACTER. 
VOL. 216. 
LONDON: 
PRINTED BY HARRISON AND SONS, ST. MARTIN’S LANE, W.C., 
printers hr (irbinarg to Pajtstg. 
July, 1916. 
