to that other wonderful fact, so important in our exploration of, and speculation upon, far-off space, namely, that this speed is identical with that of the action of gravity. And, once more, the transference of energy, in form of motion, from ordinary matter to ether, and vice versâ—a department of science afterwards so fertile of results, ought, as one would now think, to have been caught up much earlier, seeing that, even in the nineteenth century, the two media were perfectly recognizable and distinguishable, and their quality respectively—as, for example, in regard to light and sound transmission—more or less well known. Look at the result of this last step! We speak, as we all of course know, by means of air. The air-energy is exactly transferred to the ether; and thus the voice is carried, at electro-light speed, in any desired direction, to be afterwards, at its destination, retransferred to air, and to enter there the listening ear, even billions of miles away.
This beginning of our hold upon, or rather say, our actual handling of, ether, was followed by other marvellous results, when we could deal optically with that attenuated medium, isolating it from ordinary matter, presenting an ether surface for light-refraction and reflection, and thus, as by an ether microscope, catching a hugely magnified view of ordinary atoms and molecules. We thus knew, not only the shape and aspect of these bodies, but their intervening distances; and thus also, by a compound equation with other known facts, we found the interval between ether points, as well as much other knowledge, including, in particular, that of the reduction of gravity itself, in certain directions at least, to the common
