188 Dr. Tycho E:son Auren on 



which shows that all of the electrons presumably are not 

 active as outer electrons. On the other hand, if we assume 

 that 2 of the electrons are more intimately bound up to the 

 nucleus, and consequently that only 4 electrons are electrons 

 of the remotest orbit, then we obtain the values seen in 

 Table VIII., which, indeed, agree very well. Now, in 

 regard to N, all of the electrons seem to be outer electrons, 

 and the values corrected by Iq accordingly agree rather 

 closely. Similarly, we find that is probably built up of 



4 outer electrons ; thus the remaining 4 electrons must be 

 regarded as arranged in an inner region. This rearrange- 

 ment to an inner region may be regarded as causing the 

 above change by a sudden leap in the absorption of the said 

 element. For F (Z = 9) we are probably right in regarding 



5 and for Na (Z=ll) 7 electrons to be outer electrons. In 

 the elements O-Na the inner region, with 4 electrons as 

 constituent parts, would then remain unchanged. How 

 the four electrons, which so would form the inner region 

 of the elements O-Na, are arranged in relation to each 

 other, is a question to which, of course, my experiments 

 cannot give an answer. Starting from the Rutherford-Bohr 

 atom model, the simplest view seems to be that all of the four 

 electrons are arranged in one ring. It maybe well to remember 

 that Vegard * has shown that from quantum-theory this atom 

 model would lead to the result that the inner ring may be 

 built up of either three or four electrons. With four electrons 

 we arrive, according to Vegard, at a particularly simple 

 formula to calculate the frequency in spectra of X-rays ; 

 but the author, however, for certain reasons, thinks it more 

 plausible that the ring is built up of only three electrons. 



Another rearrangement, due to the passing of 4 other 

 electrons to the inner region, seems to take place at 

 Mg (Z = 12). The outer region of Mg-atom would then 

 contain 4 electrons, and after correction by 4</ we get 

 almost constant values of ^ M /c . The found values of 



K ajC\x gi ve ro occasion to think of any change at Al and P. 

 The outer region of Al would consist of 5 and that of P 

 of 7 electrons, which, as shown by the table, is in good 

 agreement with the observed values. Concerning Si (Z = 14), 

 we obtain the following values after correcting by 6q : — 



I. II. III. IV. 



"si/Cu -6 ? = 7 ' 05 6 ' 91 6 ' 81 6 ' 48 

 To estimate with greater degree of certainty the number 

 of outer elections by means of the said correction is 

 * Vegard, Phil. Mag. xxxv. p. 302 (1918). 



