Cotter mill to Crank.

Cotter mill. (Mach.) A milling cut­ter used for cutting key seats, slots, and grooves.
Cotter pin. (Mech.) Usually a form of Split pin which is inserted into a hole near the end of a bolt to pre-' vent a nu~ from working loose.
Cotton gin. (Textile) A machfue for pulling the fibers of cotton from the seeds. It was invented by Eli Witney in 1793 and was responsi­ble for a tremendous development of the cotton industry.
Cotton waste. Made of waste cotton t:Iueads. Used around engine rooms for "wiping down."
Cotton-wood. (Wood) Also known as Carolina poplar; a large tree 50 to 75 ft. in height and up to 6 ft. in diameter. The wood is soft, warps easily, is hard to sptit. Used forpa­per pulp, boxes, crates, etc.
Coulomb. (Elec.) A unit of electrical quantity A quantity of electricity delivered by a cUrrent of 0lle amphere maintained for one second. .
Coumarone indene resin. (Chern. Plast.) Used principally to m,odify the properties of other resinous bodies or compounds based on them. Its avail~bility ranges from viscous liquids to high melting solids with colour range from light yellow to almost black; much used in mastic floor tile, protective coatings, transcription records, etc.
Counter. A device for registering numbers, as the number of persons passing through a turnstile, or the number of parts being turned out by a machine.

Counter-balance. (Mech.) The addi­tion of weight, usually to a wheel of crank, in order to place the same in ­perfect balance.
Counter-bore. (MeCh.) To enlarge a hole through part of its length by boring. (Mach.) The cutting tool is sometimes fitted with a pilot or leader to guide and center the cut­ting edges. For example the enlarg­mg of the beginning of a drilled hole so that the head of a screw will be flush with the metal surface.
Counter-bracing or cross bracing. (Arch.) Diagonal bracing used in a truss or girder for giving additional support to the beam and relieving it of transverse stress.
.Counter-clockwise. (Auto.) A. direc­tion opposite to the rotation of the hands of a clock.
Counter E.M.F. (Elec.) An opposing' electromotive force which resists the current in a ciJ:cuit. (C.E.M.F.)
Counters. (Engin.) Auxiliary diagO­nal members in a truss to take a re­versal of stress.
Counter-shaft. (Mech.) The interme­diate shaft between line shaft and machine.
.'Counter-sink. (Mech.) To recess a hole conically for the head of a screw or rivet. The tool with which a hole is countersunk. .
Counter-weight. A weight attached to give balance; as a weight fastened to the rim of a wheel.
Count of Cloth . (Textile) The number of warp and filling threads in a square inch of fabric.

Country beam. (Auto. Mech.) The upper beam of an automobile head lamp designed to give a good driv­ing light on an open highway. This beam is used only in cqutnry driv­ing when there are no approaching vehicles.
Coupe. (Auto.) An enclosed single­compartment body with accommo­dations for two passengers. Usually has a luggage compartment in rear deck.
Couple. (Mech.) Two forces which are equal and act in opposite direc­tions, producing rotation.
Coupled-inductance. (Elec.) Voltages induced in one circuit by current changes in a second circuit.
Coupling. (Plumb.) A fitting with in­side threads only, used for connect­ing two pieces of pipe.
Course. (Masonry) To arrange in a row or course. A row of bricks when laid in a wall is called a "course" .
Course light. (Aero.) A light pro­jected along the course of an air­way so as to be visible chiefly from points on or near the airway.
Court. (Arch.) An open space sur­rounded partly or entirely by a building.
Court cupboard. A short cupboard, originally set on a side table, but later built as one piece.
Cove. (Arch.) A large, hollow cor­nice; also a niche.
Cove ceiling. (Arch. ) A ceiling which springs from the walls with a curve.
Covemolding. (Arch.) A concave molding.
Cover mold. (Plast.) The stationary half of an injection mold; also called "front mold."

Cover papers. (Print.) Heavy papers used for covers for booklets; also used where a strong sheet is needed for an individual mailing piece.
Cover plate. (Engin.) A plate added to the flange sections of a column or girder to increase resistance to bending.
Cowl. (Auto. Mech.) That part of an automobile body between the hood and the instrument panel, forming a shroud.
Cowling. (Aero.) A removable cover­ing which extends over or around the engine and sometimes also over a portion of the fuselage or nacelle.
Cracking. (Chern.) A process of in­creasing the yield of gasoline from crude oil by the application of heat and pressure to kerosene and fuel oil. (Paint and Lacquer) Deep open checks in film occurring in the filler coats, but which later affect colour coats, are the outgrowth of improper mixing of materials.
Crackl.e. (Ceram.) The fme network of cracks in the fmish of a piece of ware, produced for decorative purposes.
Craft. Skill in the execution of manual work. An occupation; a trade.
Craftsman. A skilled workman, par­ ticularly one who combines origina­lity with workmanlike skill.
Cramp iron. (Fdry.) A bent iron used with a wedge to clamp the drag and cope together in foundry practice.
Crane. A machine operated by hand, electric, or hydraulic power, used for the lifting of heavy weights by the use of gear wheels, cable drum, cable and jib.
Crane ladle. (Fdry.) A ladle for carry­ing molten metal, so heavy that it must be carried by a crane.
Crank. (Mech.) A lever which rotates

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