teen feet from the nozzle of the pump, a man can raise in an hour, with common working, about thirty-eight hogsheads, which far exceeds the work performed by the wheel; but this calculation is made on pumps of the common size, I would therefore propose that all vessels should carry larger pumps, the advantage of which will appear from the following table: A 4 inch bore will discharge per hour, sailing at the rate of five knots,

9 hogsheads,

Hence we find, that a pump of eight inches bore, will discharge with the wheel nearly the same quantity that a man commonly raises. If both pumps be set to work by the crank, double the quantity, or seventy-four hogsheads will be discharged; but if a cog-wheel, of about three feet ten inches, with fifty-one cogs, be fixed on the end of the shaft or axis, and the crank be passed through a trundle or lanthorn wheel, of about two feet diameter, with thirteen rounds, to work with the axis parallel to the deck, and fixed to the pumps, in the manner used by brewers and distillers, the crank will make about four turns to one revolution of the great wheel, and of course deliver 296 hogsheads per hour; yet as the resistance made by the pumps will, in some measure, impede the motions of the wheel, it will not turn at the rate of 730 times in an hour, for which suppose a deduction of one third, which is certainly a great allowance, the quantity then discharged per hour is about two hundred hogsheads, which is more than equal to the constant work of five men; thus if a vessel sailing at the rate of five knots, delivers two hundred hogsheads per hour, equal to five men's work,

I am aware of many objections that will be suggested. In the first place it will be said, that pumps of eight inches bore, will be too large to be worked by the strength of men, when the wheel cannot be applied. I answer, no more force is required to discharge a gallon of water at a stroke from an eight inch, than from a four inch bore; as the short end of the lever or handle to the eight inch bore, need not be above a quarter part the length of the four inch, which will give a purchase to the sailor at the long end of the lever, sufficient to raise the piston or spear a quarter of the height of what is required in a

four inch bore, for a piston moving three inches in an eight inch bore, will deliver just about the same quantity of water. It will be further objected, that in stormy weather, when vessels generally make the most water, the wheel could not be put overboard. I own there is some force in this objection, but if a remedy iş beneficial in some cases, though not adequate in all, it ought not to be totally rejected. Many leaks happen at sea in moderate weather, and even those which are occasioned by damage in a storm, often continue when the waves are abated. Sailors are frequently unhappily washed overboard, and possibly those who may have survived the storm, are too few, and too weak, to keep the ship clear of water, and perform the other necessary duties on board, in such cases, this machine would be eminently useful. It may also be urged, that the wind at such time may be so much ahead, that the ship cannot make way enough through the water to work the pumps; to which I reply, when life is in danger, when grim death stares the affrighted crew in the face, the port of destination is not to be considered, but the vessel must be steered for that shore, which best suits the working of the pumps, and keeping her above water.

I would therefore propose, that every vessel should not only have pumps of eight inches bore, but be provided with a shaft, crank, and proper wheels, which might easily be stowed away in little room, as the paddles of the water wheel may be unshipped, and the whole procured at a small expense.

These hints, together with the model, I submit to the inspection of the Society, and hope some improvement may be made on this plan, which will prove useful to mankind.

REFERENCES. PLATE XVI.

A. Topmast or shaft of the wheel. B. Oars or arms of the wheel. C. Crank. D. Pump. E. Props on the deck, to support the shaft.

On Leaks.

If a ship is generally leaky in the seams of her bottom, the best remedy is fothering, which is thus done: Sew oakum to a sail; then let the sail down over the bows, with ropes, and confine it to that part of the vessel's bottom which is leaky. But this very much impedes the ship's sailing; therefore, if the leak is not of great length, or even if there are several of them, it would be better to nail over them leather or tarred canvas. When I was mate of the sloop Illinois, of Philadelphia, in 1792, she sprung a leak near the garboard streak. The leak was considerable; it was a spall in the plank next a seam. A rope was

girted taught round the vessel's bottom, near the place of the leak, and made fast to each gunwale. A slack rope was made fast to it. By a bowling knot in another rope I went down, and nailed leather over the spall, coming up occasionally to breathe. This effectually stopped the leak. The holes for the nails must be first made in the leather.

REMARK. The vessel must be hove to while this is performed.

To prevent Boats from Foundering at Sea.

Span a small spar, and make a rope fast to the bight of the span; which being done, put it overboard, and pay out 7 or 8 fathoms. Let the boat ride under the lee of this spar, which will keep off the violence of the sea.

The only time that I have found a necessity of resorting to this expedient, it was completely effectual. I was at that time mate of the brig Active, of Philadelphia, commanded by Nathaniel D. Gardner, which was cast away on a reef about three miles to the eastward of the Hogsties. There are two small, low, sandy keys, bearing N. W. and S. E. from each other, and a reef of coral rocks extending, in the form of a half moon, from one key to the other, with several channels through this reef, through which boats may pass. The distance between these keys is about two miles; and these, together with the inside of the reef, form a kind of bay, where there is from 10 to 15 feet water; in some places of which, there are sandy spots, where small vessels may anchor. The S. E. key is round, about 300 feet in diameter; the N. W. 900 feet in length, and 300 in breadth. These keys are nearly even with the surface of the water. The N. W. key bears from the N. W. point of Great Heneaga S. E. by S. distant 40 miles.

We landed on the N. W. key with 26 passengers; and as our vessel filled with water shortly after she struck, we obtained from her but a scanty portion of provisions and water. After remaining on the key six days, our provisions and water becoming very short, Captain Gardner permitted me to rig the long boat with a sail, and go in search of some vessel, or endeavour to get to Cape Nichola Mole, in the island of St. Domingo. On the 30th March, 1794, at 3 P. M. with the wind at S. E. I set sail, with two men, and a passenger, Mr. Granier. The weather was fine; the wind scant. In about an hour we lost sight of the keys, and at 6 P. M. a squall blew from the N. W. accompanied by rain. I saw a frigate to the N. W.; but as she was to the windward, I saw no prospect of getting to her. I therefore kept the boat before the wind. The sea being very high, nut a rope out astern, having understood that in such cases