Jib.
1. (Nautical.) A large triangular sail set on a stay, forward of the fore stay-sail, between the fore-top mast-head and jib-boom in large vessels. It occupies a position between the mast-head and bowsprit in cutters, schooners, and small craft, and does not necessarily run on a stay. Jibs are known by various names, according to position, etc., as inner-jib, outer-jib, standing-jib, flying-jib, spindle-jib, storm-jib, jib-of-jibs, etc. A jib-topsail or balloon-jib extends towards the topmast head, and in cutter yachts is sometimes a very large sail.
2. (Machinery.) The extended arm of a crane; or that spar of a derrick which is stepped at the bottom and connected by tackle at the top to the vertical post. The post a is maintained vertical by guys, and the tackle affords a means for adjusting the inclination of the jib b, the fall being carried from the top of the post to a small crab on the ground, distinct from the larger crab which operates the hoisting-tackle. See crane; derrick. The jib of a derrick is stepped, and is adjustable in inclination. The jib of a crane is fast to the frame and rotates horizontally with it, or is journaled to the frame and is adjustable thereon. Sometimes vertically, for hight; always horizontally for sweep.
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| Jib and post. |
