To whatever results investigations of this kind may lead, their chief interest lies for the present in the possibilities they offer for the production of an efficient illuminating device.  In no branch of electric industry is an advance more desired than in the manufacture of light.  Every thinker, when considering the barbarous methods employed, the deplorable losses incurred in our best systems of light production, must have asked himself, What is likely to be the light of the future?  Is it to be an incandescent solid, as in the present lamp, or an incandescent gas, or a phosphorescent body, or something like a burner, but incomparably more efficient?

There is little chance to perfect a gas burner; not, perhaps, because human ingenuity has been bent upon that problem for centuries without a radical departure having been made—­though this argument is not devoid of force-but because in a burner the higher vibrations can never be reached except by passing through all the low ones.  For how is a flame produced unless by a fall of lifted weights?  Such process cannot be maintained without renewal, and renewal is repeated passing from low to high vibrations.  One way only seems to be open to improve a burner, and that is by trying to reach higher degrees of incandescence.  Higher incandescence is equivalent to a quicker vibration; that means more light from the same material, and that, again, means more economy.  In this direction some improvements have been made, but the progress is hampered by many limitations.  Discarding, then, the burner, there remain the three ways first mentioned, which are essentially electrical.

Suppose the light of the immediate future to be a solid rendered incandescent by electricity.  Would it not seem that it is better to employ a small button than a frail filament?  From many considerations it certainly must be concluded that a button is capable of a higher economy, assuming, of course, the difficulties connected with the operation of such a lamp to be effectively overcome.  But to light such a lamp we require a high potential; and to get this economically we must use high frequencies.

Such considerations apply even more to the production of light by the incandescence of a gas, or by phosphorescence.  In all cases we require high frequencies and high potentials.  These thoughts occurred to me a long time ago.

Incidentally we gain, by the use of very high frequencies, many advantages, such as a higher economy in the light production, the possibility of working with one lead, the possibility of doing away with the leading-in wire, etc.