Q. E. D. | Page 4

even more strikingly illustrated by the behavior of discharges of electricity through rarified gases, as well as by the facts of radioactivity. To quote the words of Sir J.J. Thompson, "The transparency of bodies to Roentgen rays, to cathode rays, to the rays emitted by radioactive substances, the quality of the secondary radiation emitted by the different elements, are all determined by the atomic weight of the element."[1]
[Footnote 1: Encyclop?dia Britannica, Vol. XVII, 891. Cambridge Edition.]
Just recently we have had opened up before us a still more intimate inner-circle view of the composition of matter. H.G.J. Moseley, a young man only twenty-six years of age, at an English university, devised a method of examining the spectra of the various elements by means of the X-rays. He found in this way that the principal lines of these various spectra are connected by a remarkably simple arithmetical relationship; for when the elements are arranged in the order of their atomic weights, they show a graded advance from one to another equal to successive additions of the same electrical unit charge, thus indicating a real gamut of the elements that we can run up by adding or run down by subtracting the same unit of electrical charge. It is pitiable to have to record that next year this scientific genius was killed in the ill-fated Gallipoli expedition against Turkey.
Thus in many fairly independent ways we are brought around to this same idea of a common structure underlying all the many seeming diversities manifested by what we call matter.
The phenomena of radioactivity were discovered accidentally in 1896 by the French chemist Becquerel. Many investigators immediately began working along this promising line, and two years later Madam Curie, in association with others, discovered the new element radium. Soon it was discovered that radium and several other substances are continually giving off radiations at an enormous rate, that no change of chemical combination, no physical change of condition appears to have the slightest effect in slowing or increasing this discharge of emanations, while no scientific apparatus yet devised can detect any change in the substances left behind either in respect to weight or any other properties as the result of these enormous losses of energy. Accordingly some people not unnaturally were ready to draw the conclusion that those most firmly established laws of physics and chemistry, the laws of the conservation of energy and of matter, were overthrown by this astonishing behavior of these newly discovered substances. However, only a few more years of study and investigation were necessary to prove that this last conclusion was wholly unwarranted; and to-day these laws of the conservation of energy and of matter are more firmly established than ever.
The thing that has gone by the board is the old idea of the atoms as the indivisible and irreducible minima of the material universe. For not only do all the radioactive substances give off particles of helium gas positively electrified, but _all bodies, no matter what their composition_, can by suitable treatment, such as exposing them to ultra-violet light, or raising them to incandescence, be made to give off electrons or negatively charged particles, and these electrons are always the same no matter from what kind of substance they come. In a somewhat similar way, we always get positively electrified particles of the mass of the hydrogen atom, or about 1,760 times the mass of the electron, whenever we send an electric charge through a gas at very low pressure, no matter what the kind of gas. Whether or not these positive units will yet prove susceptible of being split up into smaller particles comparable to the electrons, is merely a subject for conjecture. We have no proof that they will. At the present time what we call matter seems to be composed of these positive units and of the electrons which are about 1/1760 as great; and in the present state of our knowledge these facts suffice to explain all the properties of matter. Thus we can either say that electricity is composed of matter, or say that matter is composed of electricity; and human language at best is such a clumsy vehicle of thought that scientifically and philosophically the one statement is as correct and as reasonable as the other.
And probably we shall never be able to learn any more than this. We have arrived at a sort of box-within-a-box theory of the make-up of matter. By a very elaborate system of unpacking, or by some violent external force that makes the inside burst open, as it were, we seem to be able to make pieces fly off from the atoms, these pieces being then projected into space with enormous force and velocity. There are theories galore of the structure of the atom; but as Prof. E.P. Lewis