338 RADIO-ACTIVE PROCESSES 

inactive products which arise, is a measure of the total amount of 
energy released. 
There seems to be no reason to suppose that the atomic energy 
of all the elements is not of a similar high order of magnitude. 
With the exception of their high atomic weights, the radio- 
elements do not possess any special chemical characteristics which 
differentiate them from the inactive elements. The existence of 
a latent store of energy in the atoms is a necessary consequence 
of the modern view developed by J. J. Thomson, Larmor, and 
Lorentz, of regarding the atom as a complicated structure consisting 
of charged parts in rapid oscillatory or orbital motion in regard to 
one another. The energy may be partly kinetic and partly potential, 
but the mere arrangement of the charged particles, which probably 
constitute the atom, in itself implies a large store of internal 
atomic energy. 
It is not to be expected that the existence of this store of 
latent energy would have ordinarily manifested itself, since the 
atoms cannot be broken up into simpler forms by the physical or 
chemical agencies at our disposal. Its existence at once explains 
the failure of chemistry to transform the atoms, and also accounts 
for the independence of the rate of change of the radio-active 
processes of all external agencies. It has not so far been found 
possible to alter in any way the rate of emission of energy from 
the radio-elements. If it were ever found possible to control at 
will the rate of disintegration of the radio-elements, an enormous 
amount of energy could be obtained from a small quantity of | 
matter. 
206. Possible causes of disintegration. In order to ex- 
plain the phenomena of radio-activity, it has been supposed that a 
certain small fraction of the radio-atoms undergoes disintegration 
per second, but no assumptions have been made as to the cause 
which produces the instability and consequent disintegration. 
The instability of the atoms may be supposed to be brought about 
either by the action of external forces or of forces inherent in the 
atoms themselves. It is conceivable, for example, that the appli- 
cation of some slight external force might cause instability and 
consequent disintegration, accompanied by the liberation of a large 
