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Another (Let a quantity of ballast even)

Let a quantity of ballast, even more than what is commonly used for sailing, be laid in the bottom of the boat; over this lay bags filled with cork, prepared for the purpose, and numbered according to their places, and if considerably higher than the gunwales, so much the better. A sail or part of one, folded, may be thrown over from stem to stern, to combine and unite the several parts; and, lastly, the whole is to be secured together by passing ropes by so many turns as may be deemed sufficient round and round over the gunwales and under the keel, and these, if necessary, may be hitched by a turn or two taken lengthwise.

Every person either on board or holding by the boat, so prepared, may be absolutely certain of being carried safe through any beach whatever.

When no such preparation of cork has been made, the following is proposed as a substitute:

Let a quantity of ballast, as coals in canvas, be secured in its place, as well as circumstances will admit; then take an empty water-cask (beer-cask, or any others that are tight) and fill the boat with them, and if the bilge of the cask rises considerably higher than the gunwales, it will be so much the better; let a sail then be thrown in to jam the cask and ballast in their places, as well as to combine and unite the several parts by covering all fore and aft; and, lastly, let the whole be lashed and secured together, in the manner above stated.

It is believed the boat in this trim would always continue upright on her keel, be lively and buoyant on the water, and have sufficient efficacy to support the crew of any ordinary vessel, till drifted within their own depth.

It frequently happens that after men have gained the shore, they perish of cold for want of dry clothes. As a remedy for this, every man should try to secure one or two flannel or woollen shirts, by wrapping them up tightly in a piece of oiled cloth or silk; and, to guard against tearing, the last might be covered with canvas, or inclosed in a tin box. wrecks.

Further Method of Preservation in Cases of Ship- It being the great object, in cases of shipwreck, to establish a communication betwixt the vessel and the shore with the least possible delay, various methods have been invented and pointed out for this purpose.

A common paper kite launched from the vessel, and driven by the wind to the shore, has been supposed capable of conveying a piece of packthread, to which a larger rope might be attached and drawn on board.

A small balloon, raised by rarefied air, might be made to answer the same purpose.

A sky-rocket, of a large diameter, has also been considered as capable of an equal surface, and, indeed, this method seems the best; for, besides the velocity of the discharge, could it be brought to act during the night, it must both point out the situation of the ship, and the direction that the line took in flying ashore.

Useful Hints when a Leak is Sprung.

When a vessel springs a leak near her bottom, the water enters with all the force given by the weight of the column of water without, which force is in proportion to the difference of the level between the water without and that within. It enters at first therefore with more force, and in greater quantity than it can afterwards, when the water within is higher. The bottom of the vessel, too, is narrower, so that the same quantity of water, coming into that narrow part, rises faster than when the space for it is larger. This helps to terrify; but, as the quantity entering is less and less as the surfaces without and within become more nearly equal in height, the pumps that could not keep the water from rising at first, might afterwards be able to prevent its rising higher, and the people might remain on board in safety, without hazarding themselves in an open boat on the wide ocean.

Besides the equality in the height of the two surfaces, there may sometimes be other causes that retard the farther sinking of a leaky vessel.

The rising water within may arrive at quantities of light wooden works, empty chests, and particularly empty water-casks, which, fixed so as not to float themselves, may help to sustain her.

Many bodies which compose a ship's cargo may be specifically lighter than water. All these, when out of water, are an additional weight to that of the ship, and she is in proportion pressed deeper in the water, but as soon as these bodies are immersed, they weigh no longer on the ship; but, on the contrary, if fixed, they help to support her, in proportion as they are specifically lighter than the water.

Temporary Nautical Pump.

Captain Leslie, in a voyage from North America to Stockholm, adopted an excellent mode of emptying water from his ship's hold, when the crew were insufficient to perform that duty. About ten or twelve feet above the pump he rigged out a spar, one end of which projected overboard, while the other was fastened, as a lever, to the machinery wave this was reversed, for, by the weight of the butt, the piston came up again, and with it the water. Thus, without the aid of the crew, the ship's hold was cleared of the water in a few hours.

Another. When a vessel springs a leak at sea, which cannot be discovered, instead of exhausting the crew by continual working at the pumps, they may form, with very little trouble, a machine to discharge the water, which will work itself, with out any assistance from the hands on board.

Let a spar, or spare top-mast, be cut to the length of eight or ten feet, or more, according to the size of the vessel; nortise four holes through the thickest end, through which run four oars, fixing them tight, exactly in the middle. To the four handles nail on four blades (made of staves), the size of the other ends, which will form a very good water-wheel, if the oars be strong; then fix into the opposite end what is commonly called a crank: the iron handle of a grindstone would suit extremly well; if this is not to be had, any strong bar of iron may be bent into that form, wedging it tight to prevent its twisting round. Then nail up a new pair of chaps on the fore part of the pump, for a new handle to be fixed in, which will point with its outer end to the bow of the vessel.

This handle will be short on the outside, but as long on the inside as the diameter of the bore of the pump will admit, in order that the spear may be plunged the deeper, and of course the longer stroke. The handle must be large enough to have a slit sawed up it, sufficient to admit a stave edgeways, which must be fastened with a strong iron pin, on which it may work. The lower end of the stave must be bored to admit the round end of the crank; then fix the shaft, with the oars (or arms) over the gunwale, on two crotchets, one spiked to the gunwale, and the other near the pump, cutting in the shaft a circular notch, as well to make it run easier, by lessening the friction, as to keep the whole steady. A bolt is now to be fixed in each crotchet close over the shaft, to keep it from rising. As soon as the wheel touches the water it will turn round, and the crank, by means of the stave fixed on its end, will work the handle of the pump.

To render the Sinking of a Ship Impossible.

According to the present plan of ship-building, in case of a leak at sea, which cannot be kept under by pumping, the ship and crew must inevitably be lost, to the great affliction and loss of thousands of families. In order to prevent such accidents in future, which hitherto have been too common, a gentleman of the name of Williams suggests an easy arrangement which, if universally adopted, even under the worst circumstances, will enable the crew to save not only themselves, but the ship and cargo likewise:

It is that every ship should be divided into four equal compartments, with partitions of sufficient strength; the probability in case of a leak is that it would take place in one of them, and, allowing it to fill, the safety of the ship would not be endangered, for three-fourths of the cargo would remain undamaged. To prove this we will suppose a vessel of 100 tons so divided (though the plan is as applicable to a ship of 1000 tons as to a canal boat), and that one of the compartments filled with water; this would not increase her weight more than from six to eight tons from the cargo previously occupying the space and reduof the pump. To the end which projected over-cing her buoyancy about one-third. The same board was suspended a water-butt, half full, but corked down; so that when the coming wave raised the butt-end, the other end depressed the piston of the pump; but at the retiring of the effect would take place was she sent out of port with only one-fourth of her hull above water, though vessels are commonly sent out with onethird, and even more. Packets, as they carry lit-