ILLUSTRATION 
PLATE 1. MODELS OF THE ELECTRON SHELLS 
As the exact forces (see p. 3) acting on shell electrons are not known, 
these models are to be considered only very rough approximations to the 
actual proportions and arrangements. The arrangements shown are based 
on the assumption that magnetic attraction is the determining force. The 
white rings represent electrons revolving in orbits, or in actual ring shape, 
in a direction clockwise to the observer, the black ones, counter-clockwise. 
Paper disks are placed inside to increase the visibility. 
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