By this new system, to perfect which I am now devoting all my time and my energies, dynamos will become a thing of the past, eventually; and electric lighting will be conducted by a polar negative disk, independent of extraneous power to run it, other than that of sympathetic polar attraction, as simple in its construction, almost, as an ordinary type-writing machine. Answers made in Letters from Mr. Keely, to Questions asked of Him. Light incident to any body that absorbs or reflects it does not press upon it. The radiometer of Professor Crookes's invention is not operated by the pressure of light, but by corpuscular bombardment on the reflecting side of its vanes. You have called my attention to the receding movement in the metal silver, which it assumes when the flow of an alternating current from an electro-magnet, in front, is thrown upon it. This does not prove that light presses upon it to induce that movement. It moves by inter-atomic bombardment of some 800 millions of corpuscular percussions a second; or, more truly, by inter-sympathetic vibrations. If a homogeneous disk of gold, silver and platina, in proper proportions, were made the medium of interference, the resultant action would be startling in showing up the movement of molecular antagonistic thirds. The movement would be very erratic and gyroscopic. If the same disk were used or an intermediate transmitter to a negative focalizer, or in other words a polar radiator only one of which is in existence, by a nodal wire of gold, silver and platina, the effect on the disk at the negative terminus would be to set into action the latent force held in its molecular embrace, and would cause it to sympathetically adhere to the focalizer, with a power that would make it practically inseparable.