Gearing
a train or series of wheels with cogs for transmitting motion; the parts in machinery by which motion is communicated. In spur gearing the teeth are arranged round either the concave or convex surface of a cylindrical wheel in the direction of radii from the center of the wheel, and are of equal depth throughout. In beveled gearing the teeth are placed upon the exterior periphery of a conical wheel in a direction converging to the apex of the cone, and the depth of the teeth gradually diminishes from the base.