A machine used on board ships, chiefly for raising the anchor. It may be regarded as a modification of the mechanical power termed the wheel and axle, employed to raise buckets from wells, and for infinite variety of other uses. In nautical affairs, it consists of a large cylindrical piece of timber, moving round its axis in a vertical position, and is supported at its two ends by two pieces of wood called knight-heads, which are placed on the opposite sides of the deck, near the foremast: it is turned about by levers called handspikes, which are for this purpose thrust into holes bored through the body of the machine. The lower part of the windlass is usually about a foot above the deck: it is furnished, like the capstan, with strong iron pauls, to prevent it from turning backwards by the pull of the cable and anchor, or from being strained by the violent jerking of the ship in a tempestuous sea. The pauls fall into notches cut in the surface of the windlass, and lined with plates of iron.

The windlass is heaved round by the men who work it throwing their weight upon the ends of the handspikes, which, moving through a much greater space than the length of the cable taken up, Constitute, in effect, an increase of power equal to much greater space: and by this simple mechanical arrangement anchors of much greater weight than that of the men employed, are raised direct from the sea. It however requires considerable dexterity to manage the handspike to the most advantage: the sailors who perform it rise simultaneously upon the windlass, insert their levers, throw their weights to the extremities, by a sort of jerk, all at the same instant, and weigh up the anchor six or eight inches at each pull, the motions of the men being regulated to time by the howling of one of the crew. To save the time employed by the men in working a windlass in raising the handspikes from one slot to another, and also to give additional power to the machine, a patent was recently taken out by Mr. George Straker, a ship-builder, of South Shields, - a perspective sketch of whose windlass is subjoined. The increase of power he obtains by fixing on the barrel of the windlass, at one end, a spur wheel a, which is acted upon by a pinion b, whose axis turns in pearings which support the windlass itself.

Upon each end of the pinion axis are fixed two circular appendages c c, which are formed like two crown ratchet wheels, with only four teeth in each, placed face to face, and with the teeth directly opposite to each other, and only about an inch apart, so as to leave cavities between them of a suitable form to receive handspikes of the shape represented in the above cut, - the upper figure showing the operating end edgeways, and the lower figure the same broadways; wherein is shown a fork or slot for the reception of the axis, when it is being turned round. This forked end is of course made of iron, and sufficiently thin to pass up between the projecting teeth of the pieces c c, when withdrawn a few inches; and by this means it can be raised with facility; and when it is pushed in, its shoulders d d rest on the projecting teeth, which enables the men to turn the pinion, and through that medium the windlass acts with great power. It will be perceived that by this arrangement, instead of having, as usual, to withdraw the handspikes, and insert them in a fresh hole every time they are brought down to the deck, they have only to be withdrawn until their shoulders can pass outside of the projecting teeth, moved past a second pair of teeth, and then returned again, till the shoulders rest firmly upon them.

This is evidently a very convenient and excellent method of working a windlass, and might be applied, as stated by the patentee in his specification, to windlasses, without the intervention of the spur-wheel and pinion.

Windlass 722