PHILOSOPHICAL 
T E. A N S A C T I 
OF THE 
EOYAL SOCIETY OE LONDOI^ 
Series A. 
CONTAINING PAPEES OF A MATHEMATICAL OE PHYSICAL CHAEACTEE. 
VOL. 19(E 
LONDON: 
PRINTED BY HARRISON AND SONS, ST. JVIARTIN’s LANE, W.C., 
|h-mtcrs in ©rbiitarp to fior late P^ajcstn. 
July, 1901. 
