Gilbert:—The unit for measuring magneto-motive force, being produced by .7958 ampere-turn approximately.

Henry:—From Joseph Henry, of the Smithsonian Institution, Washington, D. C. The practical unit for measuring the induction in a circuit when the electro-motive force induced is one international volt, while the inducing current varies at the rate of one ampere per second.

Joule:—The C. G. S. unit of practical energy, being equivalent to the work done in keeping up for one second a current of one ampere against a resistance of one ohm. Named from J. P. Joule, of England.

Oersted:—From Oersted, the electrician. It is the practical unit for measuring electrical reluctance.

Watt:—The practical electrical unit of the rate of working in a circuit, when the electro-motive force is one volt, and the intensity of current is one ampere. It is equal to 107 ergs per second, or .00134 horse-power per second. Named from James Watt, of Scotland.

Weber:—The practical unit for measuring magnetic flux. Named from W. Weber, of Germany.


THE CENTURY’S NAVAL PROGRESS
By REAR ADMIRAL GEORGE WALLACE MELVILLE, U. S. N.

I. INFLUENCE OF SEA POWER.