Specification of the Patent granted to Malcolm Cowan, Commander in his Majesty's Royal Navy; for Improvements in the Construction of Sails for Ships and Vessels of all Descriptions. Dated June 11, 1805.

With Engravings.

TO all to whom these presents shall come, &c. Now know ye, that in compliance with the said proviso, I the said Malcolm Cowan do hereby describe and ascertain the nature of my said invention, and the manner in which the same is to be performed, by the plans or drawings in the margin of these presents; that is to say: The sails are to be made of canvass, or any other proper substance, article, or material, with the cloths or seams horizontal, with a reef or reefs at the foot according to the use they are intended for, and are to be so constructed, as to reef or reduce at the foot or lower parts, as well as at the head or upper parts, and to have as many reefs as may be thought necessary. The reefs are to be made with or without bands at the fore or afterpart of the sails, to reef or reduce and set again by means of the bands, eyelet-holes, ropes, lines, points, robins, gaskets, blocks, thimbles, cringles, and hanks, all, or as many of which as may be required, according to the dimensions of the sails and other circumstances. The bands to be either roped or not as may be found necessary.

Explanation of the Drawings.

The courses and top-gallant-sails to be reefed from the deck, and the top-sails by one man or more at each lower yard arm. A, Fig. 21, (Plate IV.) the after part of the sails. B, a strong band on the after or fore part of the sails, sewed on at the upper part only, and roped at the lower parts. C, the long clews of the course formed by the bight of the leech rope, and rope of the reef band, with thimbles seized in above the tack blocks for lashing the lower clews to. D, the tacks and sheets fitted to the upper clews of the courses with thimbles'above the tacks blocks. E, The buntlines brought up through the thimbles H, on the foot ropes of the sails and bent to the cringles I, on the ropes of the reef bands. F, small ropes or gaskets rove occasionally as a reef line in separate pieces through eyelet-holes under the reef bands, and made fest to the middle or quarters of the sail for confining the slack sail when reefed, in the wake of the reef bands and quarters. G, thimbles in the clews, earings, and leeches. K, thimbles on the foot rope with earings rove through them. L, the reef tackle pendants passing through thimbles in the clews of the top sail, and brought up and bent to the cringles above the upper reef band. M, a boom tackle or burton hooked to the reef pendants. N, the crowfoot legs to the top-gallant buntline, for keeping the slack sail up clear of the stay.

N. B. The reef bands are sewed by the upper part to the after part of the sails, to prevent the rope from girting the sail when the whole sail is set. The rope of the reef band of the course is the same size as the common foot rope, and the foot ropes must be in proportion to the rate of the ship: for first rates, three three-quarters or four inch; second rates, three and an half; third rates, three inch rope, as the quantity of sail below the reef band does not require so strong a foot rope as when the whole sail depended on it. The rope of the reef bands of the top-sails should be smaller than the leech ropes, as the foot of the sail will be considerably strengthened when reefed. These sails are not so heavy as the common ones. A seventy-four gun ship's course is reduced in weight about two hundred pounds, as the points, bands, and eyelet-holes of the old reefs are not required, nor any additional geer. Men of war will find one reef at the foot of the top-sails very useful in chace, in squally weather, or when obliged to haul suddenly on a wind or on other occasions; merchants' ships will only require two reefs in the top-sails, as the squarest part of the sail is taken off by reefing at the foot instead of the head, but more reefs may be added if necessary. When the courses are to be reefed, cast off the lower clews from the thimbles in the upper clews, haul up the slack sail by the buntlines, and haul tort the reef line one part at the time from the middle of the sail towards the clews, and make it fast round the upper clews, so as to confine the lower clews; to set the sail, reeve a few turns of the lashing for the clews, and haul them down, over-hauling the reef line and buntlines; to reef the top-sails, send a man up to each lower yard arm, settle the hallyards, and haul the sail down by the reef tackles, and pass the turns of the earings through the thimbles in the earing cringles and on the foot rope, and make them fast; hoist the sail tort up, haul through the slack of the buntlines, and haul tort the reef line on each side towards the clews and make fast; the top-gallant sails are reefed from the deck by the clew lines and a single buntline with a crowfoot; the buntlines and reef lines will confine the slack sail when reefed close up in the wake of the reef band, and the buntlines will only require to be kept hand tort as is usual to prevent them from chafing the sail.

Advantages proposed.

To enable ships to reef their courses in a few minutes when on a lee shore in stormy weather, when it may be necessary to reduce the sails, at the same time dangerous to take their effect off the ship by hauling them up, to reef them on the yard; or, when the ships' crews are reduced by sickness, by part of them being in prizes, or employed on shore, or weakened by labour or fatigue; in gales of wind in frosty weather when it is difficult to handle the sail; in merchants' ships with few seamen, and partly manned with invalids, Lascars, Indians, or negroes, &c. &c. The sails can be hauled up and set again in less time, as one part of the sail is taken off or set again at a time, and consequently receives less of the force of the wind. When ships are obliged to carry a press of sail in squally weather, in chace or other occasions, the sails may be reefed and set again in a minute, without starting tack or sheet, or risque of splitting; if a sail should split in one part, it would be stopped by the reef bands. When the sail is hauled up, it will be almost furled to the yard, from the buntline being brought abaft the sail, and bent to the cringles on the rope of the reef band. The weight of the reefs is removed from the yard to the foot of the sail, without encreasing the strain on the yards. The sails being reduced at the foot instead of the head will stand longer and better in a gale of wind, as the squarest part of the sail is taken off when reefed. When carrying sail in action, these sails can be hauled up at the lower part out of the way of the fire from the guns, or in fishing the anchor, as the fore sail is very often in the way, particularly to leeward. The expense of these sail will be less, and they will last longer from not being so liable to split in hauling up or setting; half worn sails are worth altering, as there will be a considerable saving in the wear and tear of the sails. Ships with these sails will make quicker voyages from the safety with which they can carry sail by day or night, and in many situations would be in perfect safety, when ships with the old sails might be utterly lost.


The sails made on this plan are applicable to ships and vessels of every description, and may in many situations that ships are liable to be in, be the means of saving them from destruction, particularly in the winter season, when so many ships are unavoidably exposed in gales of wind to the dangers of lee shores and narrow seas.

N.B. One principal object of my invention is, the application of a reef or reefs at the bottom of the sails, which has not been heretofore; but the same may either be used alone, or in conjunction with a reef or reefs at the top of the sails, as at present in use. Another object of my invention is, to have the cloths of which the sails are made, and seams or joinings, horizontal instead of vertical; but my improvement in reefing is equally applicable to sails, the cloths and seams of which are vertical. Another improvement is shewn in sail marked O in the said drawings, which may be applied to ships and vessels of all descriptions using fore-and-aft sails, and may serve occasionally for awnings, and facilitate the management of brigs, ketches, schooners, sloops, and cutters, in blowing or bad weather, in witness whereof, &c.

The Repertory of Arts, Manufactures, and Agriculture. Consisting of Original Communications, Specifications of Patent Inventions, Practical and Interesting Papers, Selected from the Philosophical Transactions and Scientific Journals of all Nations. Volume IX. Second Series, London, 1805. pp 88-92

Transcribed by Lars Bruzelius.

The Maritime History Virtual Archives | Rigging | Search.

Copyright © 2009 Lars Bruzelius.