PHILOSOPHICAL TRANSACTIONS 
OF THE 
ROYAL SOCIETY OF LONDON. 
Series A, Vol. 217. Pp. 237-278. 
[Plates 2 and 3.] 
ON PHENOMENA RELATING TO THE SPECTRA 
OF HYDROGEN AND HELIUM. 
BY 
T. R. MERTON, D.Sc. (Oxon), 
LECTURER IN SPECTROSCOPY, UNIVERSITY OP LONDON, KING’S COLLEGE, 
AND 
J. W. NICHOLSON, M.A., D.Sc., 
PROFESSOR OF MATHEMATICS IN THE UNIVERSITY OF LONDON. 
LONDON:' 
PUBLISHED BY THE ROYAL SOCIETY, 
AND SOLD BY HARRISON AND SONS, ST. MARTIN’S LANE, W.C., 
printers; in <©riiinarn to iHajcstn. 
1917. 
A 555. 
11.8.17. 
Price Two Shillings and Sixpence. 
