*Antennae.* A forwardly-projecting feeler, or hair-like appendage. Applies to the wires of a wireless telegraphy outfit, which are elevated, and receive the high tension impulses. *Anti-friction.* A device or means to prevent the action of rubbing or wearing. *Armature.* A body of iron or other suitable metal, which is in the magnetic field of a magnet. *Arbitrary.* Stubborn determination. Doing a thing without regard to consequences. *Asphaltum.* A combustible mixture of hydrocarbons; mineral pitch; also found in certain crude oil. *Atmosphere.* The mass or body of gases surrounding the earth. *Attributable.* To ascribe something to a state or condition. *Automatic.* So made that it will operate without any external aid or mechanism. *Available.* That which can be made use of. *Auxiliary.* An aid; added to; giving or furnishing aid. *Battery.* A combination of two or more cells. *Bearing.* A term applied to a metal housing in which a journal or shaft turns. *Bell-crank.* A lever, which is bent at right angles, and is pivoted to swing at the point near the right angled bend. *Binding post.* A stud or projection, usually provided with a hole to receive a screw, and adapted to hold a wire. *Buckled.* Specifically bent or distorted out of shape, but particularly applied to storage battery plates which are bent. *Carbureter.* A mechanical device which is so arranged that it will receive and discharge a certain proportion of air, and mix therewith a quantity of hydro-carbon vapor. *Carbureted air.* Air which is charged with a vapor of hydro-carbon gas, like gasoline.