THE 

 LONDON, EDINBURGH and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIEKCE. 



+* — - 



[SIXTH SERIES. 

 APRIL 1914. 



LXIV. The High-frequency Spectra of the Elements, and ike 

 Structure of the Atom. By J. W. Nicholson, M.A., D.Sc, 

 Professor of Mathematics in the University of London*. 



IN the Philosophical Magazine for December last, Mr. H. 

 G. J. Moseley has described some experiments which 

 give a new order of simplicity to the determination of wave- 

 lengths of the characteristic X-radiation emitted from metals, 

 — a determination which, when performed with sufficient 

 completeness, supplies perhaps the most hopeful way of 

 obtaining a more intimate knowledge of the inner structure 

 of the atom, and of the essential relations between the various 

 elements. The results of the experiments are remarkable, 

 and indicate a definite law which appears to connect succes- 

 sive elements in the Periodic Table. But at the same time, 

 the particular interpretation of these results which has been 

 suggested appears to the writer to be very unsatisfactory, 

 and in calling attention to some points of theory which have 

 been overlooked, not only in this interpretation but also 

 almost universally in recent work on the possible nature of 

 atoms, an opportunity is afforded of scrutinising, in a general 

 way, some of the fundamental assumptions involved in such 

 work, restricting attention, however, only to certain special 

 points on which erroneous conclusions have been founded. 



A very attractive theory as to the nature of series spectra 

 has been put forward recently by Dr. Bohr f, and it has been 



* Communicated by the Author, 

 f Phil. Mag-. July and Sept. 1913. 



Phil. Mag. S. 6. Vol. 27. No. 160. April 1914. 2 



