COMPLEMENT. The proper number of men employed in any ship, either for navigation or battle. In navigation the complement of the course is what it wants of eight points; of latitude, what it is short of 90°. (_See_ CO-LATITUDE.) COMPLEMENT OF LONGITUDE. _See_ SUPPLEMENT OF LONGITUDE. COMPLETE BOOK. A book which contains the names and particulars of every person borne for wages on board, as age, place of birth, rating, times of entry and discharge, &c. COMPLIMENT, TO. To render naval or military honour where due. COMPO. The monthly portion of wages paid to the ship's company. COMPOSITION NAILS. Those which are made of mixed metal, and which, being largely used for nailing on copper sheathing, are erroneously called _copper nails_. COMPOUND. A term used in India for a lawn garden, or inclosed ground round a house. COMPRADOR [Sp]. A Chinese contractor in shipping concerns, or in purchasing present supplies. COMPRESS. A pad of soft linen used by the surgeon for the dressing of a wound. COMPRESSION OF THE POLES. The amount of flattening at the polar regions of a planet, by which the polar diameter is less than the equatorial. COMPRESSOR. A mechanism generally adopted afloat for facilitating the working of the large guns recently introduced; the gun-carriage is thus compressed to its slide or platform during the recoil, and set free again by the turn of a handle for running up. It is of various forms; one of the simpler kind used to be always applied to carronade slides. COMPRESSOR-STOPPER. A contrivance for holding the chain-cable by compression. COMPROMISE. The mutual agreement of a party or parties at difference, to refer to arbitration, or make an end of the matter. COMPTROLLER OF THE CUSTOMS. The officer who controls and has a check on the collectors of customs. (_See_ CONTROLLER.) COMPTROLLER OF THE NAVY. Formerly the chief commissioner of the navy board, at which he presided. COMRADE. A barrack term for a fellow-soldier, serving in the same company. CONCEALMENT, OR SUPPRESSIO VERI. Consists in the suppression of any fact or circumstance as to the state of the ship, the nature of her employ, and the time of sailing or expected arrival, material to the risk of insurance, and is fatal to the insured. But it is held immaterial to disclose the secret destination of privateers, the usages of trade, or matters equally open to both parties. CONCENTRATED FIRE. The bringing the whole or several guns to bear on a single point. CONCH. A large univalve, used as a horn by pilots, fishermen, &c., in fogs: a _strombus_, _triton_, or sometimes a _murex_. CONCHS. A name for the wreckers of the Bahama reefs, in allusion to the shells on those shores. Though plunder is their object, the _Conchs_ are very serviceable to humanity, and evince both courage and address in saving the lives of the wrecked.