With atoms broken up into corpuscles, the problem of the nature of matter shifts one step farther back, and becomes the problem of the nature of these tiny bodies. Of this problem two rival solutions are now in the field, offered respectively by the conservatives and the liberals. The former, while admitting that a corpuscle is in the main an electric charge, or field of electric force, maintain that the charge has a nucleus or carrier at its core, which alone is entitled to be called matter, in distinction from the electricity of the charge. Lenard, who has given to corpuscles the significant name of dynamides, has calculated the diameter of this center of actual matter, so called, and found it to be smaller than 0.3 of 10-10, i. e., smaller than three hundred thousand millionths of a millimeter. This means that the actual matter, so called, of a cubic meter of so heavy an element as platinum, occupies at most one cubic millimeter of space, the rest of the cubic meter being empty of Lenard's matter, and in fact entirely empty of ponderable matter, but for the electric charges.
With so much of matter acknowledged to be electric force, which to that extent successfully performs all the functions which used to be attributed to matter, it is natural, say the liberals, to inquire whether the whole of matter can not be reduced to force, whether matter is not just force and nothing more. Many facts, they say, make this altogether the more probable, indeed the only comprehensible, hypothesis.
In the first place, as Sir Oliver Lodge, who shares with Professor J. J. Thomson—another hard-headed Englishman—the distinction of leading the liberals, points out, "an electric charge possesses the most fundamental and characteristic property of matter, viz., mass or inertia." If the charges occupying a given space are sufficient, and their potential is sufficiently high, their combined mass will equal, and exhaustively account for, the observed mass of the matter occupying the space. This conclusion was theoretically established long since, and has recently received experimental confirmation from laboratory studies on radio-activity.
On these points, I quote the statement of Professor Bigelow, of the University of Michigan:
- Popular Science Monthly, August, 1903.