20 Preston— Radiating Phenomena in a Strong Magnetic Field. 
belongs to Kayser and Runge’s second subsidiary series, being the first terms, 
corresponding to » = 3, in their formula. We should, consequently, expect 
these groups to behave similarly in the magnetic field, and to show effects which 
are similar for corresponding lines. ‘hat this expectation is realized is shown by 
the following Table :— 
Magnesium. Cadmium. Zinc. mje or A?/5A. Character. 
5183°8 5086 4810-7 18 approx. Complex triplets. 
5172°'8 4800 4722 Li og Quartets (Sextets). 
5167°5 4678 4680 10 a Pure triplets. 
Thus the corresponding lines 5183°8, 5086, and 4810°7 of the different 
substances possess the same value for m/e, while the other corresponding lines 
also possess a common value for the quantity m/e. The value of this quantity 
changes from one set of lines to another, showing, as we should expect, that the 
different sets arise from differences in the source which produces then. 
Not only is the quantity m/e the same for corresponding lines in the same 
and in homologous spectra, but, as shown in the above Table, the character of 
the magnetic effect is also the same for corresponding lines. ‘Thus, while the 
lines along the lowest row, 5167, 4678, 4680 are all of the pure triplet type, 
the lines of the middle row all become resolved into similar quartets in the 
magnetic field, and the lines forming the top row are all somewhat diffuse, and 
show as “‘soft” triplets, of which the constituents may be really complex on 
further resolution. 
It thus appears that the observation of the radiating phenomena in the 
magnetic field is likely to afford a valuable means of inquiry into the so far 
hidden nature of the events which bring about the radiation from a luminous 
body, and also give us, perhaps, some clearer insight into the structure of 
matter itself. 
