TRUNDLE-HEAD. The lower drumhead of a capstern, when it is double, and worked on one shaft both on an upper and lower deck.
TRUNDLE-SHOT. An iron bolt 16 or 18 inches long, with sharp points, and a ball of lead just inside each head.
TRUNK. (See [Rudder-trunk].) Also, a large species of turtle. Also, a place for keeping fish in. Also, an iron hoop with a bag, used to catch crabs and lobsters.—Fire-trunks. Funnels fixed in fire-ships under the shrouds, to convey the flames to the masts, rigging, and sails.
TRUNK-ENGINE. A direct-acting steam-engine, in which the end of the connecting-rod is attached to the bottom of a hollow trunk, passing steam-tight through the cylinder cover.
TRUNK-FISH. A name of the Ostracion, a fish remarkable for having its body encased in an inflexible armour of hard octagonal plates, the fins, mouth, and gill-openings passing through holes in this casing.
TRUNNION-RING. The ring round a cannon next before the trunnions, now disused.
TRUNNIONS. The arms, or two pieces of metal projecting from the opposite sides of a gun, by which it rests and swings upon its carriage, acting as an axis of elevation or depression. Also, pieces of well-seasoned wood, used in securing the ship's timbers.
TRUSS. The trusses or parrels of the lower yards serve to bind them to their masts and are bowsed taut when the yards are trimmed, in order to arrest motion and friction. But the introduction of an iron goose-neck, centering and securing the yard well free of the mast, very much supersedes the use of trusses.
TRUSS-HOOPS. Synonymous with clasp-hoops for masts or spars; they are open iron hoops, so made that their ends, being let into each other, may be well fastened by means of iron wedges or forelock keys.
TRUSS-PARREL. That part of a rope-truss which goes round the yard.