the particles of magnetic bodies, &c. 91 
of any mass should be more than a proportional part of the 
whole, does not appear extraordinary ; but that the removal 
of a portion, in which, separately, the magnetism developed 
is represented by 2 6, should cause a diminution represented 
by 63 7 in the magnetism developed in the mass, or more than 
24 times its separate effect ; and that the separation should 
be nearly equivalent to the removal, are striking, and, I think, 
important facts in the investigation of the laws according to 
which magnetism is communicated to, and distributed in re- 
volving bodies. These results are in perfect accordance with 
those which I have deduced from the experiments with the 
disc I. 
It follows then from these experiments, that, in the de- 
velopement of induced magnetism by rotation, every portion 
of a mass contributes towards the intensity of the magnetism 
developed, and that in a much greater ratio than would, by 
direct induction, be due to that portion according to its 
distance from the magnet ; so that there appears to be, as it 
were, an accumulation of magnetism arising from the mutual 
action of the several particles upon each other ; continuity 
throughout has thus a much greater influence than mass : a 
complete solution of continuity, when it does not take place 
in the parts adjacent to the magnet, is very nearly equivalent 
to an entire removal of the remoter mass so separated ; and 
in all cases, the effect produced by complete separation is not 
much less than that produced by removal. 
