PHILOSOPHICAL TRANSACTIONS 
OF THE 
EOYAL SOCIETY OE LONDON. 
Series A, Vol. 220. Pp. 109-136. 
THE PRESSURE UPON THE POLES OF THE 
ELECTRIC ARC. 
BY 
W. G. DUFFIELD, D.Sc., 
PROFESSOR OP PHYSICS, CAPTAIN, ROYAL AIR FORCE, 
THOS. H. BURNHAM, B.Sc., and A. H. DAVIS, B.Sc., 
POST-GRADUATE STUDENTS IN PHYSICS, UNIVERSITY COLLEGE, READING. 
Printed and Published for the KOYAL SOCIETY by 
HARRISON AND SONS, 44^7, ST. MARTIN’S LANE, LONDON, W.C. 2, 
iprintersl tu <9rIftnarB to :Waje^tB. 
1919. 
Price Three Shillings. 
574^ ■ 22.12.19 
