The question of the nature and properties of ether, its structure, its motion, its limits, if it possesses any

One of the most arduous problems is that of energies acting at distances. Are they real? Of all those that appear incontrollable, one only remains, gravitation. Will it escape us also? The laws of its action incline us to think so. The nature of electricity is another problem which recalls us to the condition of electric and magnetic forces through space. Behind this question arises the most important problem of all, that of the nature and properties of the substance which fills space, the ether, its structure, its motion, its limits, if it possesses any. We find this subject of research, day by day, predominating over all others. It seems as though a knowledge of ether should not only reveal to us the nature of that imponderable substance, but will unveil to us the essence of matter itself and of its inherent properties, weight and inertia. Soon the question set by modern physics will be, Are not all things due to conditions of ether? That is the ultimate end of our science; these are the most exalted summits to which we can hope to attain. Shall we ever reach them? Will it be soon? We cannot answer.