THE 
SCIENTIFIC PROCEEDINGS 
OF THE 
ROYAL DUBLIN SOCIETY. 
Vol. XI. (N.8.), No. 24. FEBRUARY, 1908. 
ON THE 
QUANTITATIVE SPECTRA OF MOLYBDENUM, 
TUNGSTEN, THORIUM, AND ZIRCONIUM. 
Loe 
A. G. G. LEONARD, A.R.C.S.L, 
ROYAL COLLEGE OF SCIENCE, DUBLIN. 
(PLATE XXIV.) 
[Authors alone are responsible for all opinions expressed in their Communications. | 
DUBLIN: 
PUBLISHED BY THE ROYAL DUBLIN SOCIETY, 
LEINSTER HOUSE, DUBLIN. 
WILLIAMS AND NORGATE, 
14, HENRIEITA-STREET, COVENT GARDEN, LONDON. W.C. 
1908. 
Price Sixpence. 
