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Hand crank for a winch on a sailboat - commonly referred to as a winch handle. A crank is an arm attached at a right angle to a rotating shaft by which circular motion is imparted to or received from the shaft.
Winch used on a fishing boat to bring in nets. The earliest literary reference to a winch can be found in the account of Herodotus of Halicarnassus on the Persian Wars (Histories 7.36), where he describes how wooden winches were used to tighten the cables for a pontoon bridge across the Hellespont in 480 BCE.
The gates are opened and closed by a hand-crank, gear, and spar. The locks are flooded by gear-operated butterfly valves at the upstream end and emptied by butterfly valves at the downstream end. Each lock lifts a boat about 10 feet (3.0 m), can fill in about four minutes, and empties in about three minutes.
The tensioned portion of the rope would fasten the ship to the quay, hoist a foresail, lift a spar into position on the mast or be used to transfer cargo to or from a dock or lighter. A capstan is a vertical- axled rotating machine developed for use on sailing ships to multiply the pulling force of sailors when hauling ropes, cables , and hawsers .
Vitruvius, a military engineer writing about 28 BC, defined a machine as "a combination of timber fastened together, chiefly efficacious in moving great weights".About a century later, Hero of Alexandria summarized the practice of his day by naming the "five simple machines" for "moving a given weight by a given force" as the lever, windlass, screw for power, wedge, and tackle block (pulley).
Lift nets can be hand-operated, boat-operated, or shore-operated. They typically use bait or a light-source as a fish-attractor. [1] Lift nets are also sometimes called "dip nets", though that term applies more accurately to hand nets. [2] Lift nets are hauled out by hand or mechanically through boom(s) and blocks.