will not find so feeble as the first,
to entertain you.

Give me leave to introduce the subject in a few words.

A short time ago I had the honor to bring before our American
Institute of Electrical Engineers[A] some results then arrived at by
me in a novel line of work. I need not assure you that the many
evidences which I have received that English scientific men and
engineers were interested in this work have been for me a great
reward and encouragement. I will not dwell upon the experiments
already described, except with the view of completing, or more clearly
expressing, some ideas advanced by me before, and also with the view
of rendering the study here presented self-contained, and my remarks
on the subject of this evening's lecture consistent.

[Footnote A: For Mr. Tesla's American lecture on this subject see THE
ELECTRICAL WORLD of July 11, 1891, and for a report of his French
lecture see THE ELECTRICAL WORLD of March 26, 1892.]

This investigation, then, it goes without saying, deals with
alternating currents, and, to be more precise, with alternating
currents of high potential and high frequency. Just in how much a very
high frequency is essential for the production of the results
presented is a question which even with my present experience, would
embarrass me to answer. Some of the experiments may be performed with
low frequencies; but very high frequencies are desirable, not only on
account of the many effects secured by their use, but also as a
convenient means of obtaining, in the induction apparatus employed,
the high potentials, which in their turn are necessary to the
demonstration of most of the experiments here contemplated.

Of the various branches of electrical investigation, perhaps the most
interesting and immediately the most promising is that dealing with
alternating currents. The progress in this branch of applied science
has been so great in recent years that it justifies the most sanguine
hopes. Hardly have we become familiar with one fact, when novel
experiences are met with and new avenues of research are opened. Even
at this hour possibilities not dreamed of before are, by the use of
these currents, partly realized. As in nature all is ebb and tide, all
is wave motion, so it seems that; in all branches of industry
alternating currents--electric wave motion--will have the sway.

One reason, perhaps, why this branch of science is being so rapidly
developed is to be found in the inte