ADDRESS. 7 
It is but a century ago that the title of an ether to a place among the 
constituents of the universe was authentically established. It seems 
possible now that it may be the stuff out of which that universe is wholly 
built. Nor are the collateral inferences associated with this view of the 
physical world less surprising. It used, for example, to be thought that, 
mass was an original property of matter, neither capable of explanation 
nor requiring it ; in its nature essentially unchangeable, suffering neither 
augmentation nor diminution under the stress of any forces to which it 
could be subjected ; unalterably attached to each material fragment, 
howsoever much that fragment might vary in its appearance, its Ce! its 
chemical or its physical Beadstions 
But if the new theories be accepted, these views must be revised. 
Mass is not only explicable, it is actually explained. So far from being 
an attribute of matter considered in itself, it is due, as I have said, to the 
relation between the electrical monads of which matter is composed and 
the ether in which they are bathed. So far from being unchangeable, it 
changes, when moving at very high speeds, with every change in its velocity. 
Perhaps, however, the most impressive alteration in our picture of the 
universe required by these new theories is to be sought in a different 
direction. We have all, I suppose, been interested in the generally 
accepted views as to the origin and development of suns with their 
dependent planetary systems ; and the gradual dissipation of the energy 
which during this process of concentration has largely taken the form of 
light and radiant heat. Follow out the theory to its obvious conclusions, 
and it becomes plain that the stars now visibly incandescent are those in 
mid-journey between the nebulee from which they sprang and the frozen 
darkness to which they are predestined. What, then, are we to think of 
the invisible multitude of the heavenly bodies in which this process has been 
already completed ? According to the ordinary view we should suppose 
them to be in a state where all possibilities of internal movement were 
exhausted. At the temperature of interstellar space their constituent 
elements would be solid and inert ; chemical action and molecular move- 
ment would be alike impossible, and their exhausted energy could obtain 
no replenishment unless they were suddenly rejuvenated by some celestial 
collision, or travelled into other regions warmed by newer suns. . 
This view must, however, be profoundly modified if we accept the 
electric theory of matter. We can then no longer hold that if the 
internal energy of a sun were as far as possible converted into heat either 
by its contraction under the stress of gravitation, or by chemical reactions 
between its elements, or by any other inter-atomic force ; and that were the 
heat so generated to be dissipated (as in time it must be) through infinite 
space, its whole energy would be exhausted. On the contrary, the 
amount thus lost would be absolutely insignificant compared with what 
remained stored up within the separate atoms. The system in its 
corporate capacity would become bankrupt—the wealth of its individual 
