Feed. To furnish an electric current, also spoken of in connection with the mechanism that moves the carbons in arc-lamps.
Feeders, or Feed Wires. The conductors which convey electric currents at different points, as in the trolley system. The current is carried along in large cables strung on poles or laid underground, and at proper distances lines are run in to feed the trolley wire.
Field. The space in the neighborhood of a dynamo or motor, or other generator of electric current, from which the apparatus takes its electricity, both electrostatic and magnetic.
Field-magnet. (See [Magnet, Field].)
Field of Force. The space in the neighborhood of an attracting or repelling mass or system. There are two kinds of fields of force—the electro-magnetic and the static—from which the respective pieces of apparatus draw their store of electricity.
Filament. A long, thin piece of solid substance. It is generally as thin as a thread and flexible enough to be bent.
The hairlike element in an incandescent lamp which, when heated by a current, glows and radiates light.
Filaments, Paper. Filaments for incandescent lamps made of carbonized paper. They were the ones originally used in electric lamps, but have been superseded by other substances easier to handle and more durable.
Flow. The volume of a current or stream escaping through a conductor, such as a wire, rod or pipe.
Fluorescence. The property of converting ether waves of one length into waves of another length. The phenomenon is utilized in the production of Geissler tubes and X-rays.