Correspondence.
The Constitution of Matter and its Motions.—Universal Gravitation Produced by the Motions of Ether.—Hypothesis of M. L’Abbé Leray.—M. Riche on the New Chemical Notation.—New Sensitive Pigment Paper.
In one of my recent letters to this Journal I was deploring the want of some grand hypothesis which would embrace in one general law all the mechanical phenomena of nature—universal gravitation, cohesion, chemical affinity, electricity, magnetism, light, heat, &c.—and lo! just such a hypothesis has turned up and been explained to me by its author—a man whom I am compelled to regard, without any exaggeration, as one of the great geniuses of the present day. I allude to M. L’Abbé Leray, author of a work to which I referred in a recent letter, entitled Constitution de la Matière et ses Mouvements.
I will endeavour to give an outline—but it can only be an outline—of this startling hypothesis, which makes universal gravitation an effect of the motions of ether, and dispels the idea hitherto entertained that it is an attractive force inherent in particles of matter, by which they are enabled to exert a pull upon other particles at a distance from them in space.
Sir Isaac Newton, the immortal discoverer of the law of universal gravitation (which asserts that every particle of matter in the universe attracts every other particle with a force which varies directly as the mass and inversely as the square of the distance), himself believed that this law would be found, at some future time, to result from the motions of a subtle fluid which occupied space, the atoms of which, by impinging against ponderable matter, produce the observed effect of weight or gravitation. He could not conceive of ponderable matter possessing any inherent property by which it was enabled to act upon other ponderable matter at a distance. He could not really believe in an inherent central force of attraction residing in a material atom, by which it could draw towards itself another such atom situated at a distance, or that it could affect other matter in any way than by the impact of intervening atoms; and he predicted that some day the cause of universal gravitation would be discovered. That day seems now to have arrived, and the discovery to have been actually made.
I had read M. Leray’s extraordinary work with a great deal of interest, but there were still some unexplained points in his hypothesis which remained to be cleared up and some difficulties to be discussed. As he resides at an ecclesiastical institution within an easy walk of Redon, I visited him a few days ago, by appointment, for the express purpose of having a long talk over his hypothesis; and a very pleasant afternoon I had with him, leaving more deeply impressed than ever with a sense of his great abilities and originality. In fact, I seem to have made the acquaintance of a second Sir Isaac or Laplace.
The following is an outline of his theory; but of course no demonstration of any part of it can be made within the limits of this letter:—
Space is filled with a subtle ether, consisting of atoms in motion. These atoms are elastic—a property which they possess in virtue of being able to change their form, though not their volume, during impact and to recover it again. Their form is spherical, they are all equal, and their diameter is very small compared with that of the atoms of ponderable matter, and also with their general distance apart. This ether is, therefore, an exceedingly rare medium. When the atoms impinge against each other they rebound like billiard balls, and in all their motions they obey the common mechanical laws of inertia and impact, and no other laws whatever. They cannot act upon each other at a distance, and therefore no attractive or repulsive force exists between them.
If only one of these atoms were to exist in space it would move in a straight line with uniform velocity until it reached the limit of space; that is to say, the boundary by which creation is limited—the boundary which separates entity from nonentity. Here, being elastic, it would be reflected, and would then follow another rectilinear course until it again encountered in another point the boundary of space, where it would be again reflected; and so on for ever!
If we imagine space filled with an enormous number of such atoms it will follow that at every point in space there will be small parallel currents of them moving in all directions. Their distance apart being great in proportion to their size, two contrary currents will not annihilate each other, but by far the greater number of atoms in one current will pass those in the other current without impact. Those atoms which do impinge against opposite atoms, at various angles of incidence, will rebound and join other currents which are moving in their new direction.