Project Gutenberg #4710
The Story of Electricity
John Munro
1902Munro's popular history of electrical science and its early applications, prepared chapter by chapter from Project Gutenberg HTML.
Project Gutenberg #4710 Public domain in the United States Cover source Local typographic cover created for MojiMori from public-domain source metadata
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UNITS OF MEASUREMENT.
(From Munro and Jamieson's Pocket-book of Electrical Rules and Tables).
I. FUNDAMENTAL UNITS.—The electrical units are derived from the following mechanical units:—
The Centimetre as a unit of length; The Gramme as a unit of mass; The Second as a unit of time.
The Centimetre is equal to 0.3937 inch in length, and nominally represents one thousand-millionth part, or 1/1,000,000,000 of a quadrant of the earth.
The Gramme is equal to 15.432 grains, and represents the mass of a cubic centimetre of water at 4 degrees C. Mass is the quantity of matter in a body.
The Second is the time of one swing of a pendulum making 86,164.09 swings in a sidereal day, or 1/86,400 part of a mean solar day.