202 



Dr. Tycho E:son Auren on 



In fig. 4 the connexion between ^, calculated by the 



P 

 formula (18), and Z is given graphically. As we find 

 from the figure, the values, except for H and Li, are 

 distributed to three hyperbolas corresponding to p=7 7 

 p = 5,p = 4: respectively. 



0-4- 



0-3 



0-2 



0-1 



Fiy. 4. 



14- 16 



But in regard to H, the Table XIY. shows that the mass 

 scattering coefficient also may be expressed by the formula 



£ _ 0-205p 



P - z ■ 



(19) 



For elements, in case of which p = Z, that is identical with 

 the known value given by Barkla for the light elements. 

 In case of H, the formula (19) is not applicable and by 

 means of it we get a value that is merely about half the 

 real. This, however, is in good agreement with experience ; 

 for after what is shown by the experiments of Barkla and 



Crowther, - is twice as great for H as for other lighter 



elements. The exceptional position seemingly occupied 

 by H is in appearance only, and may be fully explained if 

 one takes as granted that not all electrons which constitute 

 the atom, but merely the outer ones, give off scattered rays. 

 On the other hand, as has been clearly made out, not only 

 by above-mentioned experiments on C, N, and O, but also 



