SHEEP-SHANK: a sort of knot or hitch cast on a rope, to shorten it as occasion requires: particularly to increase the sweep or length of a tackle by contracting its runner. By this contrivance the body to which the tackle is applied may be hoisted much higher, or removed much farther, in a shorter time.
Thus if any weighty body is to be hoisted into a ship, and it be found that the blocks of the tackle meet before the object can reach the top of the side, it will be necessary to lower it again, or hang it by some other method, till the runner of the tackle is sheep-shanked, by which the blocks will again be separated to a competent distance.
SHEER, relevement, the longitudinal curve of a ship’s deck or sides.
SHEERING, in navigation, the act of deviating or straying from the line of the course, either to the right or left, so as to form a crooked and irregular path through the water. It is commonly occasioned by the ship’s being difficult to steer, but very often from the negligence or incapacity of the helmsman. Hence, to sheer off is to remove at a greater distance.
SHEERS, machine à mater, an engine used to hoist-in or displace the lower masts of a ship. See the article Mast.
The sheers employed for this purpose in the royal navy are described under the article hulk. In merchant-ships this machine is composed of two masts or props, erected in the same vessel wherein the mast is to be planted, or from whence it is to be removed. The lower ends of these props rest on the opposite sides of the deck, and their upper parts are fastened across, so as that a tackle, which depends from the intersection, may be almost perpendicularly above the station of the mast, to which the mechanical powers are applied. These sort of sheers are secured by stays, which extend forward and aft to the opposite extremities of the vessel.
SHEET, écoute, a rope fastened to one or both the lower corners of a sail, to extend and retain it in a particular station. See Clue and Sail.
When a ship sails with a lateral wind, the lower corner of the main and fore sail are fastened by a tack and a sheet; the former being to windward and the latter to leeward: the tack, however, is entirely disused with a stern-wind; whereas the sail is never spread without the assistance of one or both of the sheets.
The stay-sails and studding-sails have only one tack and one sheet each: the stay-sail-tacks are always fastened forward, and the sheet drawn aft; but the studding-sail-tack draws the outer clue of the sail to the extremity of the boom; whereas the sheet is employed, to extend the inmost.
To haul home the Sheet. See Home.