DICTIONARY OF

Shear Hook 305 Sheer Off
Shear Hook.* Barbed hook that was fitted to yard arm of fireship to hook into rigging of
any enemy vessel it collided with.
Shearing Stress/Strain. Force that is exerted so that it tends to make one part of a member
slide over the other part; so exerting a scissors-like action on fastenings passing
perpendicularly through both parts.
Sheathed. Said of a steel vessel when her underwater surface has been covered with wood to
which copper sheathing has been fastened.
Sheathing. Protective covering. Particularly applied to copper placed on underwater surface
of ships to prevent fouling and attacks of marine animal life. Also applied to wooden linings
in holds, etc.
Sheathing Nail. Flat-headed cast nail of tin and copper alloy. Used for nailing copper
sheathing on underwater surface of a wooden or sheathed vessel.
Sheave. Grooved wheel in which a rope runs and alters its direction. May be of metal or
wood; lignum vitae being usual in the latter.
Sheave Hole. Aperture in which a sheave is fitted.
Sheepshank. Manipulation of a rope by which its effective length is reduced, and can be
restored quickly. Rope is bighted so that three parts lie alongside and a bight is at each end;
half hitch, in same rope, being passed over each bight.
Sheer. The upward sweep, from amidships to forward and aft of a vessel's freeboard deck.
Also, the amount that the forward of after end of a deck is higher than midship part when
keel is horizontal. Standard sheer, in inches, is 0.2 of vessel's length in feet+20 inches, for
forward sheer; half this amount for after sheer.
Sheer Batten. Wooden batten used for same purpose as sheerpole.
Sheer Draught. 'Sheer Plan.'
Sheer Head Lashing. Used when rigging sheer legs. Heads are crossed and end of lashing is
timber hitched to one leg, above the crutch. Taut turns are then passed, working downward.
Finished off with three or four trapping turns around all parts, end being clove hitched to
sheer head above the crutch.
Sheer Hulk. Old vessel fitted with sheers for stepping, or removing masts of ships.
Sheer Lashing. Variation of sheer head lashing. Rope is middled and passed round cross of
legs. Turns are taken upwards with one part, downward with the other. When sufficient
turns, ends are brought to centre and lashed.
Sheer Legs. Two splayed legs forming sheers.
Sheer Line. Line of main deck at its junction with ship's side.
Sheer Mast. One leg of a pair of sheers.
Sheer Mould. Thin wood template with one edge shaped to indicate sweep of deck sheer;
used for transferring sheer line to side of plating.
Sheer off. To move away obliquely.