Circuit, Voltaic

Properly a circuit including a conductor and voltaic couple. It is also applied to the electric circuit, q. v., or to any circuit considered as a bearer of current electricity. Circular Units . Units of area, usually applied to cro sectional area of conductors, by whose use area is expre ed in terms of  circle of unit diameter, usually a circular mil, which is the area of a circle of one-thousandth of an inch diameter, or a circular millimeter, which is the area of a circle of one millimeter diameter. Thus a wire one-quarter of an inch in diameter has an area of 250 circular mils; a bar one centimeter in diameter has an area of ten circular millimeters. [Transcriber's Note: Area is the diameter squared. A 1/4 inch wire has 62500 circular mils of area. A one centimeter (10 millimeter) wire has 100 circular millimeters of area. Actual area = circular mils * (PI/4).]