*Compounded.* The uniting of elements, in such manner that they are changed. Water is a compound. The atmosphere is merely a mixture. *Comprehension.* Understanding. A full knowledge. *Complex.* Difficult to understand. Involved. *Condenser.* A term applied to the changing of gas to a liquid state. Used in electrical devices to collect a current in high tension apparatus. *Conduit.* A channel, or an avenue through which liquids may be transported. *Conically-formed.* Made in the shape of a cone. *Conductivity.* Pertaining to the quality of a material to transmit an electrical wave or impulse. *Contracted.* Drawn in; made smaller. *Control.* Within power to handle. *Control Lever.* A bar by the side of the driver’s seat, which enables him to check the speed of the car. *Contact Maker.* A device which is designed to keep the circuit broken during the revolution of the shaft, and to throw it in only momentarily at each revolution. *Contact Breaker.* A device which is designed to keep the current established except during a small portion of each revolution. *Contact Plates.* A series of plates arranged in an electric circuit which are to be successively thrown into the circuit. *Constituent.* An element; one part of a combination of elementary substances. *Conspicuously.* Prominent. In the foreground. *Constituting.* That which comprises the elements in a material. That of which it is made. *Convolute.* A spiral form of winding, like a watch spring. *Corrosion.* To disintegrate. To be eaten away by acid, or the action of any material, or by the weather. *Counterpart.* The same as; something like another; similar to. *Counteract.* To act in a contrary direction; adversely to. *Crucial.* The testing point; a difficult or trying position.