In cutters I have had the cat-heads so far aft, that the crown of the anchor has stowed close to the fore shroud; they have stowed perfectly easy, and I observed that the copper about the bows has been less injured, than in vessels which had their cat-heads further forward,

It is in our smaller and sharpest vessels its effect would be greatest, but there can be no doubt of its advantage in all ships; and should the experiment be tried, I have no doubt it will be extended to all.

*

In many ships, and all our smaller vessels, the coal-hole is also very far forward; and as the coals are a considerable weight, and not speedily consumed, I should recommend stowing them further aft, and water where they are now, and to use this water first.

There is also a very great weight in the fore extremity of a line-of-battle ship; the gunner's, boatswain's, and carpenter's stores, which it appears to me may be stowed nearer the centre the ship, by the following arrangements.

Where those stores are now stowed, to build a room to receive part of the bread from aft, keeping a clear wing passage round the bows, by which means the bread would be as well preserved as if in the after bread-room. The bread forward can be used first, or it can be taken from forward and aft alternately, as the trim of the ship may appear to require. The remaining space to be divided into store-rooms for marineclothing, slops, beds, and such light weights as are at present stowed in the after cock-pit.

All the mates, midshipmen, and assistant-surgeons to mess in the gun-room, a much more healthy and airy situation than the cock-pit, and to have a store-room in the cock-pit for the mess-utensils and sea-stores.

By the removal of bread forward the after bread-room may be considerably reduced, and the surgeon's and purser's cabins removed further aft. By such an arrangement there would be sufficient space abaft the cable-tiers for the reception of the gunner's, boatswain's, and carpenter's stores; and which would not be much abaft the centre of the ship.

In frigates also, and smaller vessels, similar arrangements should be made as far as possible; and if those were carried

into effect, there would be no necessity for extending the stowof the ballast to the after extremity, as is too often the

age

case.

In the Cruizer, "eighteen gun-brig," we were obliged to stow ballast in the bread-room-the case I believe in most of the brigs; which would not have been requisite had the anchors and coal-holes been removed further aft. Since which I believe some alteration has been made in the store-rooms; but if weight has been reduced in the fore extremity by that means, it has been increased again by the addition of a heavy forecastle, which also considerably increases the top weight, Poops and quarter boats have followed the fore-castles; and to the little ten gunbrigs, all this additional top weight has been added-even a cutter of one hundred and twenty tons follows the rage for carrying quarter boats.

I must repeat an observation of Professor Inman's, as it is most applicable to the point in question :

"It may be observed, generally, that it is advantageous to give the projected ship the requisite stability with as little ballast as possible, by which means a constructor is enabled to reduce the displacement or magnitude of the body under water, a circumstance very favourable to a ship in sailing and working. With a similar view every weight put on board, and reckoned in getting the displacement, should be kept as low as possible. No useless baggage or weights of any kind should be put on board on any account whatever."

t

Every one who can agree with Professor Inman, must condemn the system of adding so much top and overhanging weight.

3f Fore-castles were first fitted by the captains, were very light, and could not have caused much impediment to the vessels sailing; but the heavy way they are now fitted, many with heavy bulwarks above them, and other additions which have succeeded, must be materially felt.

I may be told the quarter-boats are of a light description; but when every common sailor will admit a jacket hung in the rigging to be an impediment to sailing on a wind, I say it is inconsistent to carry quarter-boats in such small vessels. But

allowing them to be of a light description, the weight of the iron davits is to be added, and it should be remembered that when a vessel is launching, although its actual weight is not, yet its power is considerably increased by the action of the vessel.

I was four years and a half first lieutenant of an eighteen gunbrig; they were then in their original state, and no vessels sailed better. I afterwards commanded a large cutter four years, and had many opportunities of sailing with brigs, in their original state. Subsequent to which I commanded a large cutter three years, and under the orders of several of the finest brigs in their present state; and I am convinced they neither sail nor work so well as formerly, and that it is attributable to the alterations which have been made.

I am also of opinion, that by taking away the poops and quarter-boats, building the fore-castles as light as possible, with only a low wash-stroke of three-quarter-inch elm or oak board above it, which would be quite sufficient, and removing the anchor and coal-holes further aft, they would be superior in their sailing qualities and as sea-boats, to what they were in their original state.

Masts are frequently raked, by some to ease a ship in a head sea, by others to improve her sailing.

It does not however occur to me that it can give much relief to a ship: for, supposing it to be the overhanging weight of the mast, acting on lever principle, which contributes to the pitching motion, the mast must be considerably beyond a perpendicular before it can have much effect; and admitting the supposition, it may naturally be supposed that a raking mast will act diametrically, and increase the sending motion aft.

But there appears to me a great objection to raking masts, in ships and square-rigged vessels.

If masts are raked, the yards are not at right angles with them, when a ship is on a wind. The consequence is, the sails are put out of their proper form, and drawn, or I may say forced, towards a diamond shape. The mainsail shows it in the diagonal girt across the sail from the tack to the lee earing; the leeches of the sails are quite slack, and bag to leeward.

It is allowed the wind acts on the same principle when striking the sails obliquely, as if perpendicular or at right angles-its power decreasing as the obliquity increases. If, therefore, the lee leeches of sails are slack and bag to leeward, the obliquity of the wind must be increased, and its power les sened. It therefore appears much preferable to give a ship relief by removing weight from the fore extremity, than by raking the masts.

I have frequently heard of various alterations having been tried in ships, to improve their sailing, and that raking the masts was the only one which proved successful. This is a circumstance which, it appears to me, may be considered as arising from some of those unknown causes alluded to by Professor Inman in the following observation :

“After all the pains the constructor may take, from the imperfection of the theory of resistances, or from some other unknown causes, it is possible that a ship, on going to sea, will not be found to have the point of sail exactly adjusted to the mean resistance. In this case, nothing can be done except by altering the masting; for effecting which, if possible, every practical facility should, in the first place, be left in the building, or by bringing the ship more by the head or stern, thus adjusting the seat of the ship in the water to the masting 'as it is."

The circumstance, however, proves an error; but where it is difficult to determine, and without being in possession of particulars, it were useless to attempt it. The ships might not have had their proper seats in the water; the point of sail might not be correctly adjusted, or it might arise from some other cause.

It is evident, however, that, seated in the water as they were, they required more after-sail-consequently could not have steered well; and it generally happens when a ship steers badly she does not sail well. The conclusion, therefore, may very naturally be, that raking the masts improved both steerage and sailing qualities.

It however appears to me, when a ship is properly seated in the water and requires more after-sail, that it is preferable to remove the foremast a little further aft than to rake the masts,

as it would have the same effect, and give considerable relief to the fore extremity.

There is one part of Professor Inman's observation—" or by bringing the ship more by the head or stern, thus adjusting the seat of the ship in the water to the masting, as it is," which it appears to me can only be meant as a temporary expedient, and till an opportunity offers to alter the masting, as it would be sacrificing a very material point-the proper seat of the ship in the water.

Plymouth, Nov. 22, 1828.

J. P.

On the Elevation of Water by the momentive Force of that Fluid in the Suction Pipe of a Pump. Communicated by R. Addams, Esq.

THE principle upon which the action of the water-ram (bélier hydraulique) depends, is known to the readers of this Journal*; but I am not aware that any one has, publicly, noticed or observed the same principle producing a similar effect without a fall or head of water. I am, therefore, inclined to suppose the following description of a hydraulic operation, which I have lately witnessed, possesses sufficient novelty to constitute an admissible article in the Journal of Science and the Arts.

In the water-ram, the momentum is generated in proportion to the velocity of the water; and the velocity is dependent upon the fall but it is obvious the same effect would take place from the same momentive force, in whatever manner this force may originate.

Now, when a common pump is worked and drawing water from a well, the air presses the water through the ingress or suction-pipe with a certain velocity: the moving water in that pipe will have a proportionate momentum; and if it be suddenly checked it will exhibit its force as in the water-ram. This I have seen verified in a pump at the house of Mr. Balaam at Clapham. I was requested to examine it, and explain its action.

* Journal of Science, Vol. I., O. S.