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PEOF. C. G. BAEKLA ON X-EAYS AND THE THEOEY OF BADIATION. 
Again, in the light of the results obtained from these experiments on bromine, the 
results of experiments on corpuscular radiation from metal plates by Beatty and 
Bragg, though somewhat irregular and decidedly fragmentary for the purpose 
of this investigation, may be seen to point to the generality of the above laws—at 
least in general features if not in detail. 
Further experiments on the corpuscular radiation from substances in the form of 
plates indicate, though with a greater possible error, that when /j. is slightly less than 
/x K the K corpuscular radiation accounts for about 0'4 of the K absorption. Such 
measurements can however, be regarded as giving only the order of magnitude of 
these quantities. 
Thus direct and indirect experiments indicate that when the wave-length of the 
primary radiation /x is just less than that (/x K ) of a fluorescent radiation, of the energy 
specially absorbed in association with the K fluorescent radiation, nearly 0'5 is 
re-emibted as energy of corpuscular radiation. As /u becomes less, the fraction 
increases, until for primary radiation of very small wave-length, nearly all the energy 
absorbed (K absorption) is re-emitted as K corpuscular radiation. The values actually 
obtained for the K energy emitted by ethyl bromide as K corpuscular radiation are 
plotted in fig. 5, Curve C, for various wave-lengths shown by the abscissas. 
Fig. 5. Stowing fraction of energy of primary beam absorbed—K absorption—transformed into K 
fluorescent (characteristic) radiation, and into K corpuscular radiation (lines FF and CC respectively). 
It is evident at once that the energy of K corpuscular radiation from bromine is 
approximately complementary to that of the K fluorescent X-radiation. A full 
discussion is, however, given later. 
