Structure of tlw Atom* 267 



equal. But a second stable arrangement can be found if 

 the moments are not all equal. Let the ratios of the moments 

 be 1 : k : k' : //' '. If r 1} r a , ? j s , i\ be the radii of the shells, 

 the conditions are 



(9' + ©' + » -<;)'-.'=»■ 

 05'+ ©'♦ ©"♦ • -"»• 



Taking the third and fourth terms as negative, and there-' 

 fore a 3 ' and « 4 ' negative, we have, for example, with 

 7- 1 /r 2 = 0'98, r» 1 /r 3 = 0-5, r^r* = 0-49, k' = l, k = k" = 5, a stable 

 arrangement which is non-magnetic* 



We have thus a model of an atom which may be 

 either magnetic or non-magnetic. Although it may be the 

 case that most examples of the non-magnetic condition of 

 substances which can exhibit magnetic quality may arise 

 from counteraction of the effects of individually magnetic 

 atoms, the possibility of counteraction of the effects within 

 the atom itself must be considered. 



In the preceding discussion the magnetic action of the 

 electrification within the thin shells has not been entered 

 upon. The distribution of electrification within them may 

 be such as to give rise to satellite lines and the observed 

 peculiarities of the Zeeman effect. 



Radioactivity may be caused by slowing down of ther 

 angular velocities of the shells producing re-arrangement of 

 the alignment of axes. Under sufficient shock it might be 

 conceivably possible for ejection of a series of shells to take 

 place — an a particle or helium atom, for example, being 

 driven out. 



One different type of radiation might arise from vibrations 

 of the axes of the individual shells, another from displacement 

 of their centres. 



The proof of the statements made on p< 265 regarding 

 equilibrium and ejection of atoms is as follows. The ex- 

 pression for the radial and tangential components of the 

 magnetic field being respectively written as N cos 6 and 



