WRING-HEADS. An ancient name given to that part of the ship near the floor-heads and second futtock heels, which, when a ship lies aground, bears the greatest strain.

YARDS. The long cylindrical pieces of timber, suspended upon the masts to extend the sails to the wind.

YACHT. A vessel of state or pleasure, usually employed to carry noble personages, and accordingly fitted with convenient apartments and suitable furniture.

YAWL. (See BOATS.)

OBSERVATIONS

ON THE

FIGURE AND CONSTRUCTION OF SHIPS AND
VESSELS IN GENERAL.

THE chief properties which every ship ought to possess, are, in a certain degree, subversive of, or in opposition to, each other; inasmuch as one figure is required for swiftness, and another for strength or capacity; and all must be regulated by the particular circumstances or designation of the intended vessel. The great art therefore consists, in so forming the body, that none of the desired qualities shall be entirely wanting, but that all shall be combined to a certain extent; giving the preference to those which are more peculiarly required in the service for which the vessel is designed.

The first and principal point, in forming a ship, whether intended for war or commerce, is, that she shall be a good sea boat; or, in other words, that she shall be able to endure, with the least possible injury, the shock of the contending elements, winds and waves.

The next object will be, to give the vessel that quality which, consistently with her destined purposes, will give her swiftness or velocity. Here arises an obstacle to perfection in the former case: the vessel of greatest draught being best calculated to make her way against adverse winds; for, having the greatest hold of the water, she is, of course, the least liable to fall to leeward; while another, of less draught, is proportionally more buoyant, and so much the better fitted for services in which particular expedition is required.

The perfection of every ship, whether intended for war or commerce, may be comprehended in four words; STRENGTH, CAPACITY, STABILITY, and SWIFTNESS; as the primary quality of safety, and the secondary qualities of steering well, working well, rolling and pitching easily, are naturally comprised therein.

The STRENGTH of a ship may be said to be in its perfection, when sufficient solidity is given to those parts that are subject to receive sudden and violent action, from the impulse of any force acting upon them; and, when sufficient strength is equally diffused throughout the whole, so that every weight shall have adequate support, and be equal to the resistance of any strain, or the operation of any irregular motion.

The best methods of imparting a due degree of strength to every part of a ship, will be amply considered hereafter, when treating upon the actual construction.

With respect to STIFFNESS OF STABILITY, it may here be observed that, in the construction of a ship of war, the first point to be attended to is, that she shall be so formed as to carry her lower tier of guns at a sufficient height from the water, in all weathers; otherwise they may be rendered useless. For a three-decked ship that cannot open her lower tier of ports upon a wind, but in smooth water only, may be taken by a seventy-fourgun ship, properly constructed, so as to keep her lower-deck ports open. The same may be said of a seventy-four-gun ship, not having sufficient stability; for she may be as easily taken by a thirty-eight-gun frigate, that can make use of all her guns; because, it is evident, that the frigate will then be the most formidable.

Hence we see, that the first thing to be considered in the construction of a ship of war is, to determine on the height of the gun-deck ports above the water at the lowest place, which is commonly at , or the midships. This we find, in line of battle ships, should invariably be from five to six feet; in frigates, from six to seven feet; and in sloops, cutters, &c. from four to five feet.

And, hence, we have the height of the Line of Floatation, or LoadWater Line, at the midships, or where the ports are lowest. Then, by determining whether the vessel should float on an even keel, or draw more water abaft than forward, we determine on the line of floatation, or load-water line, of a ship of war, with respect to the ports.

Merchant ships are generally constructed to carry a certain cargo, and their principal dimensions are determined according to the trade for which they are particularly designed; therefore the line of floatation, or load-water line, is not in them so exactly confined to a certain height.

The particular qualities required in a ship must ever regulate the figure of her bottom: a ship of war, therefore, must be formed so as to sail swiftly, and carry her lower tier of guns sufficiently out of the water. A merchant ship ought not only to contain a large cargo, but ought also to be fitted so as to be navigated with few hands; and both should have sufficient stability to enable them to carry a press of sail: they should steer well; drive little to leeward; and sustain the shocks of the sea without being violently strained.

The first thing to be established in the draught of a ship is her length; and, as a ship of war, according to her rate, is furnished with a certain number of guns, which are placed in battery on her decks, it is necessary that a sufficient distance should be left between their ports to work the guns with facility, and particularly to leave space enough between the foremost gun and the stem, and between the aftmost gun and the sternpost, on each side, on account of the arching or inward curve of the ship towards her extremities.

When the length of a ship is determined, it is usual to fix the breadth by the dimensions of the midship beam; which are generally regulated according to the experience of the builder, and the particular services for which the ship is designed. Hence have arisen that variety of standards, or general rules, adopted by different artists, who have been accordingly divided in their opinions with respect to the breadth which ought to be assigned to a ship, relatively with her length. Those who would diminish the breadth have alledged, and truly, that a narrow vessel meets with less resistance in passing through the water; 2dly, that by increasing the

L

length she will drive less to leeward; 3dly, that, according to this principle, the water lines will be more conveniently formed to divide the fluid; 4thly, that a long and narrow ship will require less sail to advance swiftly; that her masts will be lower and her rigging lighter; and, by consequence, the seamen less fatigued with managing the sails, &c.

The reasons given, on the contrary, for enlarging the breadth, appear equally cogent. These are, 1st, that this form is better fitted to preserve a good battery of guns; 2dly, that there will be more room to work the guns conveniently; 3dly, that by carrying more sail the ship will be enabled to run faster; or, that this quality will at least overbalance the advantage which the others have of more easily dividing the fluid; 4thly, that, being broader at the load-water line, or line of floatation, they will admit of being very narrow on the floor, particularly towards the extremities; and, 5thly, that a broad vessel will more readily rise upon the waves than a narrow one, &c.

All these particulars, however true in themselves, individually considered, are accompanied with their peculiar disadvantages. As, for instance, it will be evident, that, if the bow of a ship be narrow, it must unavoidably pitch deeper than one which is broader, even with a small degree of impulsion *. This can be remedied only by having its forebody so formed, that its bearings shall catch the vessel in its descent; or, in other words, by an increase of breadth or expansion upwards.

It will be necessary at the same time, that the remaining part of the hull shall be so proportioned, that its effects may not counteract the advantages arising from the figure of the fore-body; for, if the after part be not, in like manner, supported by proper bearings, it will dip into the hollow of the sea, and be so inuch the more liable to the danger of being pooped than if the bow were narrower †. A vessel so constructed, and pos-sessing length or other requisites conducing to make her wealtherly, may, if close hauled upon a wind, drive along with more than usual velocity, without dipping or sinking at every wave she meets with; but the great inconvenience will be, the danger that would inevitably exist both with respect to the masts and to the vessel.

On the form of the stern depends the prompt obedience of the vessel to the helm a proper medium must, nevertheless, be observed. If too fine and taper, the disadvantages that we have just noticed will arise; on the contrary, if too full, the vessel will not be under proper command; for the vacuum (if it may be so called) created by the passage of the hull through the water, will, in this case, extend farther than the width of the rudder; and, consequently, deprive it of its best force. But, although it is extremely requisite that all fullness in the after-body should be carefully avoided below the line of floatation, yet immediately above it the quarter should spread out, in order to present a sufficient quantity of support when the ship rises forward to a sea; and, in order to 'scend without danger of

* The movements of pitching are the most dangerous of any to which a ship is subject; as they are those which most fatigue a ship and her masts. It is mostly in one of these motions that masts are seen to break, particularly when the head rises after having pitched.

+ To be pooped, signifies, to decline so much abaft as to dip the upper part of the stern in the sea; or so much as to permit the sea to break heavily over the stern.

having her stern driven in by the force of waves that may strike her in that direction.

The stability, or stiffness, of a ship, is that quality by which, when she receives an impulse or pressure in a horizontal direction, so as to be inclined in a small degree, the vessel will regain its former position as the pressure is taken off. This quality, and the want of it, namely, the propensity of a ship to roll, depends chiefly on the figure of the midship bend.

That the nearer the midship body approaches to a cylindrical shape, the more will the ship be subject to roll, is a truth which needs no demonstration. It will be equally liable to upset if the body be too sharp, as we shall hereafter shew; besides the inconveniences of increased draught of water and smaller stowage. A vessel having a flat bottom, and perpendicular sides below the line of floatation, has the greatest stiffness; but such a vessel would, by not being sufficiently lively to yield to the sea when it runs high, be liable to have it frequently beating over her as it would over a rock. A medium, therefore, must be obtained, which shall obviate these disadvantages respectively.

The propensity to rolling, derived from the form of the midship body, may, in some degree, be obviated or reduced, particularly in a vessel of large capacity, by the length, or the peculiar qualities of the fore and after bodies; but the question is, whether the remedy would not be pro ́ductive of much greater inconveniencies.

It may be noticed here, that, according to the opinion of the best judges, in the midship frame generally, the floor should be flat, the upper futtock straight, and the extreme breadth elevated above the line of floatation.

The property of stability, as before observed, may, certainly, be considered as the first quality to be attended to in the formation and construction of a ship; inasmuch as, if that be wanting to a certain degree, it will be incapable of putting to sea with any degree of safety. Hence, therefore, the stability of a ship, whether for war or commerce, is the first property to be attended to; since, for want of it, a ship will incline too much, or lie over in the water; and, in case of action, this defect may render, in war, the lower tier of guns entirely useless.

WITH REGARD TO THE SAILING TRIM OF A VESSEL; it is the decided opinion of the most scientific men, that ships or vessels of the larger classes should always be so constructed as to sail with, or nearly with, an even keel. When constructed so as not to sail on an even keel, they draw more water abaft than forward, that being found most advantageous both to their sailing and steerage. Smaller vessels, in general, draw more water abaft than forward: some, as packets, &c. built for dispatch, considerably more so. Cutters have been, commonly, so constructed. The utility of a vessel's sailing on an even keel is considerable; as, by preserving a proper equilibrium, it preserves the trim of stowage, &c. Of such vessels it is to be particularly observed, that the breadth should be carried well forward; that the body shall diminish gradually abaft from midships; and, that the water lines forward shall not be inflected or hollow; as such are, by no means, adapted for velocity.

If built to draw more water abaft than forward, the main breadth