JERSEY. Fine wool, formerly called gearnsey, ganzee, or guernsey.—Jersey frocks, woollen frocks supplied to seamen.
JETSAM, or Jetson. In legal parlance, is the place where goods thrown overboard sink, and remain under water. Also, the goods cast into the sea.
JETTISON, or Jetsen. The act of throwing goods overboard to lighten a ship in stress of weather. The loss forms a subject for general average.
JETTY, Jettee, or Jutty. A name given in the royal dockyards to that part of a wharf which projects beyond the rest, but more particularly the front of a wharf, the side of which forms one of the cheeks of a dry or wet dock. Such a projection, whether of wood or stone, from the outer end of a wharf, is called a jetty-head.
JEW-BALANCE. A Mediterranean name of the Zygæna malleus, or hammer-headed shark.
JEWEL. The starting of a wooden bridge. Also, the pivot of a watch-wheel.
JEWEL-BLOCKS. Are attached to eye-bolts on those yards where studding-sails are hoisted, and carry these sails to the extreme ends of the yards. When these jewel-blocks are removed, it is understood that there is no intention to proceed to sea, and vice versâ. The halliards, by which the studding-sails are hoisted, are passed through the jewel-block, whence, communicating with a block on the several mast-heads, they lead downwards to the top or decks, where they may be conveniently hoisted. (See [Sail].)
JEWELS. See [Jocalia].
JEW'S-HARP. The shackle for joining a chain-cable to the anchor-ring.
JIB. A large triangular sail, set on a stay, forward. It extends from the outer end of the jib-boom towards the fore top-mast head; in cutters and sloops it is on the bowsprit, and extends towards the lower mast-head. (See [Sail].) The jib is a sail of great command with any side wind, in turning her head to leeward. There are other jibs, as inner jib, standing-jib, flying-jib, spindle-jib, jib of jibs, jib-topsails, &c.—Jib is also used for the expression of the face, as the cut of his jib. Also, the arm of a crane.—To jib, is when, before the wind, the sail takes over to the opposite quarter; dangerous in strong breezes. (See [Gybing].)—Clear away the jib! The order to loose it, preparatory to its being set.—Flying-jib. A sail set upon the flying jib-boom.—Middle or inner jib. A sail sometimes set on a stay secured to the middle of the jib-boom.