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only remedy, and the pumps must be constantly and vigilantly attended and worked, to prevent injury to the cargo, and for the safety of the vessel and crew. The pressure of water at different depths is but very partially known to many seamen, and many have expressed the greatest surprise and doubt respecting the matter. First-water presses at its base and altitude; the hole or aperture admitting the water may be considered as the base, and the depth of the hole from the surface, the altitude. Second-the quantity of water admitted into any holes or apertures of the same dimensions will be as the square roots of those depths from the surface, that is, of such numbers as, multiplied together, would make such depths; thus, at 25 feet, five times as much water would be admitted as at one foot; at 16 feet, four times; at 9 feet, three times; at 4 feet, twice; and always in those proportions; but when the water has risen in the inside of the vessel, the quantities of water admitted will be as the difference of the square roots of the surfaces inside and outside. This circumstance will show that pumps which are not powerful enough to prevent the water rising in the hold to a certain height may be quite sufficient to prevent any further increase, and thus, with a cargo that water could not destroy, a ship might be safe with many feet water in her hold, and ought not to be abandoned. It is quite probable that want of information on this very important matter has caused the abandonment of many vessels that might have been saved. From what has been stated, it is plain that a leak situated near the bottom of a vessel is, independently of its being more difficult of access, more dangerous than one near the surface.— Emmerson's Useful Hints for Young Officers.

A SEA ANCHOR.--This anchor may frequently be of the greatest possible use; it ought to be made in the following manner :-Take three spars, or topgallant or studdingsail-booms will be sufficiently large; with these spars form a triangle, the size you think will be large enough, when under water, to hold the ship; cut these spars to the required length before or after cross-lashing them well at each angle, so that they will bear an equal strain when in the water, but, should your spars be weak, you should always increase the number of your spars according to their weakness; fill up the centre of the triangle with strong canvas, having eyelet-holes round its side about three inches, to which eyelet-holes attach the canvas well to the spars; at the back of the canvas pass many turns of an inch or inch and a half rope, net fashion, of course. A proper net would be preferable to a rope so expended. To the base of the triangle attach a weight or small anchor, supported in the centre of the base by a span running from each of the

lower angles. To the first-mentioned spans make fast the stream cable; when everything is quite ready, hoist it overboard, from the place you think it will answer best. There is every reason to believe, with this anchor under the trough of the sea and 70 or 80 fathoms of stream cable out, that a ship's drift would not be very great. The plan proposed would be of the greatest advantage to dismasted vessels, and vessels which have lost their rudders, &c. If a vessel should approach the shore with this sea anchor down, it would enable her to bring-to with her proper anchors much easier than if the sea anchor had not been down. She might let go her proper anchors and veer from the sea anchor until she had sufficient cable out, which would give her a much better chance of holding. The sea anchor should have a buoy and a buoy-rope sufficiently long to go well under the trough of the sea.

MODE OF STEERING A VESSEL WHICH HAS LOST HER RUDDER.-The first thing to be done on losing a rudder is to bring the ship to the wind by bracing up the after yards. Meet her with the head yards as she comes to. Take in sail forward and aft, and keep her hove-to by the sails. A vessel may be made to steer herself for a long time by carefully trimming the yards and slacking up the jib-sheets or the spanker-sheet a little, as may be required.

Having got the ship by the wind, get up a hawser, middle it, and take a slack clove-hitch at the centre. Get up a cable, reeve its end through this hitch, and pay the cable out over the taffrail. Having payed out about fifty fathoms, jamb the hitch and rack it well, so that it cannot slip; pay out on the cable until the hitch takes the water; then lash the cable to the centre of the taffrail; lash a spare spar under it across the stern, with a block well secured at each end, through which reeve the ends of the hawser, one on each quarter, and reeve them again through blocks at the sides, abreast of the wheel.

By this a ship may be steered until a temporary rudder can be coustructed, which may be done thus:

Let a spare topmast be cut to the required length of the rudder-stock, making the heel of the mast to answer for the rudder head; use the

Capt. Liadert, R.N., in his Professional Recollections on Seamanship, &c., says he has twice tried a similar contrivance to that proposed above, and it answered beyond his expectations. "It appears preferable to riding by spars, as the spars drift so much faster than the sea anchor, from its being well under the trough of the sea, so makes great resistance to the drift of the vessel." The reason why the triangular form is proposed in preference to the square is, that the trough of the sea may strike as lightly as possible should the upper angles at any time approach the trough of the sea while riding at anchor. The square might certainly be so placed as to have one of its corners up in the same manner as the triangle, but then you would have the base in the very place you want the greatest resistance if you make a square.

remainder for the after part of the rudder, and leave a space near the lower end of the stock wherein to stow a quantity of shot, pig-iron, or the like, as ballast to assist in keeping the rudder end on. Plank it up on both sides with slabs or deals bolted or nailed to the main and after parts of the rudder, and let there be a strong shoe-piece bolted horizontally under all. Let the main piece have two mortice holes cut in it, one near the lower rudder-iron, the other about two-thirds up, through each of which pass a chain with a round turn, and carry the ends of these chains forward along the ship's counter, so that their crossings may lie against or embrace the stern-post. Clap tackles on the ends of these chains, and bowse them taut forward, in order to bind the rudder firmly against the stern-post. For greater security, also, the rudder may be hung by a rope or small chain passed through the fid-hole of the topmast, and made fast round a bar laid across the rudder-hole on deck. Bolt two spars to the upper end of the broad part of the rudder, one on each side, and lash them together in order to form a tiller projecting out from the rudder at an angle of elevation; make fast the tiller-ropes to its outer end, and lead them to the steering wheel.*

Let a spare topmast be cut the required length of the rudder, and take an iron band of sufficient sizef for the lower end of the topmast to travel in; the band, if too large, can be woolded round, and should always be leathered to prevent chafe. Next, take a lower cap, and enlarge the square hole to fit into the stern-post-the round hole is for the upper part of the topmast to travel in. Take a jib-boom and cut it in two, or take other pieces of spar and bolt the pieces on abaft the topmast, after squaring the edges which are to come in contact with each other, and cutting a score in the forward part of the jib-boom or spar, next to the topmast, at the lower end where the iron band comes, so that the working of the rudder may not be impeded; plank the whole over with stout oak planks, slabs, or deals, according to materials, and bolt in a fish abaft all. A tiller can now be fitted. The band of iron for the heel of the rudder will require a chain on each side, to reach nearly to the fore-channels, and if the material be at hand, have two eye-bolts in this band for the purpose of securing the chain to. Also have a small piece of iron plate nailed, to prevent the band from working upwards. At the fore-channels attach two tackles to the chains, to bind

*The above ingenious method for supplying a vessel with a temporary rudder, when an accident has befallen the original one, has been very justly recommended by the late Capt. Basil Hall, R.N. A description of a jury rudder for the Royal Navy, as per Admiralty Order of 28th January, 1839, will be found in Lieut. Jennings' Hints on Sca Risks.

The iron band that goes round the main-yard will answer the purpose.

the iron band close to the stern-post. Have a kedge with a slip-rope to sink the rudder, which, being put over the side and brought to the rudder trunk, can easily be hauled into its place; haul the chains taut forward, one on each side; put the cap on, ship the tiller, and put a lashing on each side the rudder-head to the deck, to keep the rudder from lifting.*

A spare cap cut away at the after-part, so as to fit the stern-post at the water's edge or a little below, may be used instead of the iron band as in the above plan, the topmast being passed through the round hole of the cap. To the topmast, which is the main piece of the rudder, will, of course, be bolted pieces of spar, so as to assume as much as possible the shape of a rudder, and pieces of plank will be nailed athwart it.

NOTE. "A ship might lose her rudder at a critical moment in crossing the bar of a river, when a few minutes more might run her aground if she were unmanageable; and, in this case, what temporary rudder is best becomes a question for which a few moments only are given to decide. The plan of steering by the stream cable payed out astern, or with the stern-boat lowered instantly, with the plug out, and towed astern by a hawser, with guys leading up to each quarter, would, perhaps, then be adopted, while a ship losing her rudder at sea would have leisure to adopt any other plan.

"It might be an advantage if every vessel would take some opportunity of trying how she could steer with a stern-boat in the manner described, and what length of towline was required to enable her to steer the most easily, so as to avoid wild yawing. The experiment might be made in moderate weather with the wind on the quarter, and also right aft, under topsails, topgallantsails, and foresail, running five or six knots. Nothing gives confidence so much as practice."-The Kedge Anchor, By W. Brady, U.S. Navy.

BOARD OF

TRADE

INSTRUCTIONS

For the Guidance of Masters and Seamen when using the Mortar and Rocket Apparatus for Saving Life.

In the event of your vessel stranding on the coasts of the United Kingdom, and the lives of the crew being placed in danger, assistance will, if possible, be rendered from the shore in the following manner, namely:

I. A rocket or shot with a thin line attached will be fired across your vessel. Get hold of this line as soon as you can, and when you have secured it, let one of the crew be separated from the rest, and, if in the day time, wave his hat or his hand, or a flag or handkerchief; or, if at

*The above plan of a jury rudder was given me at Sheerness by a gentleman, who, many years ago, constructed a rudder on this plan for a frigate of which he was carpenter. The plan is substantially the same as that given by Capt. Sedgwick, in Golden Hints to Young Mariners,

night, let a rocket, a blue light, or a gun be fired, or let a light be displayed over the side of the ship and be again concealed, as a signal to those on shore.

2.

When you see one of the men on shore separated from the rest, wave a RED flag, or (if at night) show a RED light and then conceal it; you are to haul upon the rocket line until you get a tailed block with an endless fall rove through it.

3. Make the tail of the block fast to the mast about fifteen feet above the deck, or if your masts are gone, to the highest secure part of the vessel. When the tail block is made fast, and the rocket line unbent from the whip, let one of the crew, separated from the rest, make the signal required by Article 1 above.

4. As soon as the signal is seen on shore, a hawser will be bent to the whip line, and will be hauled off to the ship by those on shore.

5. When the hawser is got on board, the crew should at once make it fast to the same part of the ship as the tailed block is made fast to, only about eighteen inches higher, taking care that there are no turns of the whip line round the hawser.

6. When the hawser has been made fast on board, the signal directed to be made in Article 1 above is to be repeated.

7. The men on shore will then pull the hawser taut, and by means of the whip line will haul off to the ship a sling life-buoy, into which the person to be hauled ashore is to get and be made fast. When he is in, and secure, one of the crew must be separated from the rest, and again signal to the shore as directed in Article 1 above. The people on shore will then haul the person in the sling to the shore, and when he has landed will haul back the empty sling to the ship for others. This operation will be repeated until all persons are hauled ashore from the wrecked vessel.

I

8. It may sometimes happen that the state of the weather and the condition of the ship will not admit of a hawser being set up; in such cases a sling life-buoy will be hauled off instead, and the shipwrecked persons will be hauled through the surf, instead of along a hawser.

Masters and crews of stranded vessels should bear in mind that SUCCESS in landing them in a great measure DEPENDS UPON THEIR COOLNESS, AND ATTENTION TO THE RULES HERE LAID DOWN; and that by attending to them many lives are annually saved by the mortar and rocket apparatus on the coasts of the United Kingdom.

The system of signalling must be strictly adhered to; and all women, children, passengers, and helpless persons should be landed before the crew of the ship.

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