284 



Absorption and Scattering of X-Rays. 



except for wave-lengths far removed from those of the 

 characteristic radiations excited in the absorbing substance. 



Fig. 2. 



•05 



(Wave -length) 3 



There were one or two minor features in our experiments 

 which we may just mention, though we have not yet had 

 time to investigate them fully. In the absorption curve for 

 paraffin, for instance, there appeared to be a consistent slight 

 irregularity at certain wave-lengths. When the absorption 

 ifi/p) in copper was about 3*5, or X = '29 x 10" 8 cm., certain 

 rather high values were obtained for the absorption in 

 paraffin, values say 10 per cent, above the normal. There 

 seems no doubt that these irregularities really exist, but 

 a permanent increase in the absorption for wave-lengths 



