BON GRACE. Junk-fenders; for booming off obstacles from a ship's sides or bows. (See [Bowgrace].)
BONITO. The Thynnus pelamys, a fish of the scomber family, commonly about 2 feet long, with a sharp head, small mouth, full eyes, and a regular semi-lunar tail.
BONI-VOCHIL. The Hebridean name for the great northern diver (Colymbus glacialis).
BONNET. An additional part laced to the foot of the jibs, or other fore-and-aft sails, in small vessels in moderate weather, to gather more wind. They are commonly one-third of the depth of the sails they belong to. Thus we say, "Lace on the bonnet," or "Shake off the bonnet." Bonnets have lately been introduced to secure the foot of an upper-topsail to a lower-topsail yard. The unbonnetted sail is for storm service. Bonnet, in fortification, is a raised portion of the works at any salient angle, having the same plan, but 10 or 12 feet more command than the work on which it is based. It assists in protecting from enfilade, and affords a plunging fire.
BONNET-FLOOK. A name of the well-known flat-fish, brill, pearl, or mouse-dab; the Pleuronectes rhombus.
BONXIE. The Shetland name for the skua-gull (Cataractes vulgaris). Also a very general northern term for sea-birds.
BONY-FISH. One of the names of the [hard-head] (which see).
BOOBY. A well-known tropical sea-bird, Sula fusca, of the family Pelecanidæ. It is fond of resting out of the water at night, even preferring an unstable perch on the yard of a ship. The name is derived from the way in which it allows itself to be caught immediately after settling. The direction in which they fly as evening comes on often shows where land may be found.
BOOBY-HATCH. A smaller kind of companion, but readily removable; it is in use for merchantmen's half decks, and lifts off in one piece.
BOOK. A commercial term for a peculiar packing of muslin, bast, and other stuffs.—Brought to book, made to account.