and the Constitution of the Atom, 275 



Our theory leaves no doubt ivith regard to the number of 

 electrons of the K- and L- sy stems ; but as regards the consti- 

 tution of the M-system we are on less certain ground, and 

 we might quite as well suppose two M-systems with quant- 

 number 3. 



The uncertainty in the case of the M-system is partly due 

 'to the limited experimental material and partly due to the 

 fact that the determination of the number of electrons of 

 a ring becomes less definite as we pass outwards from the 

 centre, and, finally, matters may be more complicated 

 and the identification of lines more difficult as we pass 

 outwards. 



General Remarks regarding Atomic Constitution. 



§ 17. The constitution here given for the K-, L-, and M- 

 ring will involve some change with regard to the general 

 scheme given in my previous paper (fig. 2) with regard to 

 the constitution of the elements. 



The first two rings will be the same as before, and the 

 surface systems for elements with atomic numbers lower 

 than 10 (Ne) should be those given in Paper I. 



The difference comes in at the third ring, which in Paper I. 

 was given a quant-number 2, while our present results have 

 given to it a quant-number 3. If, however, we assume two 

 M-systems, we may still maintain the same number of elec- 

 trons (8) of the third ring, and it is even possible that the 

 fourth ring may have 10 electrons just as indicated in 

 Paper I. 



If, on the other hand, we assume only one M-ring, the 

 third ring should be composed of 12 electrons, and provided 

 this value is the right one, we should have to give np the 

 principle that a ring once formed inside a surface ring 

 should be maintained with the same number of electrons 

 when we pass to higher atomic numbers ; for on account of 

 the periodic properties of the element we cannot assume 

 that a third ring of 12 electrons h;is been formed as a 

 surface ring for, if so, the elemeni Ti (N = 22) should 

 possess a surface ring of 12 electrons and Va (N = 23) a 

 surface ring of one electron, which cannot be assumed. 

 Although our present conception leads to some changes 

 with regard to the constitution of the internal rings, still the 

 periodic variations shown by the properties of the elements 

 indicate that the number of electrons of the surface systems 

 are those given in Paper I. 



In my previous paper I found that the electric con- 



