DORY. A fish, Zeus faber, commonly known as "John Dory," or truly jaune dorée, from its golden hues.

DOTTLE. The small portion of tobacco remaining unsmoked in the pipe.

DOUBLE, To. To cover a ship with an extra planking, usually of 4 inches, either internally or externally, when through age or otherwise she has become loosened; the process strengthens her without driving out the former fastenings. Doubling, however, is a term applied only where the plank thus used is not less than 2 inches thick.—To double a cape. (See [Doubling a Cape].)

DOUBLE-ACTING ENGINE. One in which the steam acts upon the piston against a vacuum, both in the upward and downward movement.

DOUBLE-BANK A ROPE, To. To clap men on both sides.

DOUBLE-BANKED. When two opposite oars are pulled by rowers seated on the same thwart; or when there are two men labouring upon each oar. Also, 60-gun frigates which carry guns along the gangway, as was the custom with Indiamen, are usually styled double-bankers.

DOUBLE-BITTED. Two turns of the cable round the bitts instead of one.

DOUBLE-BLOCK. One fitted with a couple of sheaves, in holes side by side.

DOUBLE-BREECHING. Additional breeching on the non-recoil system, or security for guns in heavy weather.

DOUBLE-CAPSTAN. One shaft so constructed as to be worked both on an upper and lower deck, as in ships of the line, or in Phillips' patent capstan.