THE SHIPWRIGHT.

Is a person who builds ships : a ship has been defined a timber-building, consisting of various parts and pieces, nailed and pinned together with iron and wood, in such form as to be lit to float, and to be conducted by wind and sails from sea to sea.

The word ship is a general name for all large vessels with sails, adapted for navigation on the sea ; but by sailors the term is more
particularly applied to a vessel furnished with three masts, each of which is composed of a lower-mast, a top-mast, and a top-gallant- mast.

The first attempts which mankind made in navigation were, beyond a doubt, very ancient; but it was not till after a long time, and considerable efforts and labour, that they became enabled to construct large floating-houses, capable of encountering the tempests of the winds and waves.

A thousand opportunities would of course present themselves to the eyes of mankind in the earliest ages of the world to excite the
idea of floating on the water, but nothing more readily than a tree torn up by the winds, and floating down the stream of a river. It
would be easy afterwards to collect a number trunks or other floating pieces of wood, and, by proper ligatures, form a raft. To the raft, most probably, succeeded the canoe, composed in the first place out of an old hollow tree ; from the facility with which the canoe can be managed, canoes, among the most savage nations, have been very early in use.

At what period the art of ship-building commenced, it is not easy to determine ; but the construction of boats must have preceded
that of ships. The ark of Noah is, we believe, the earliest record which we have of any building made expressly to float on the water. Ships are, however, since the time of the deluge, frequently mentioned in the scriptures. In the time of Homer, also, ships were in great use : the catalogue of, the Grecian ships forms a considerable part of one of the Books of the Iliad.

But there is great reason to believe, that all the ships of antiquity were, comparatively, of small dimensions : it has been reserved for
modern titnes, commercial speculation, and modern warfare, to demonstrate the improved powers and capacities of man for this extraordinary art.

The man of science and the practical shipwright have long lamented that, in the theory of the art of ship-building, there are so few
fixed and positive principle established by demonstration, or confirmed by practice ; thus, the artist being left to the exercise of his
own opinion, in general resists theoretical propositions, however speciously formed, so hard has it ever been found to overcome habitual prejudices. The great neglect of the theory of ship-building is much to be deplored in a country like this, where the practical part is so well understood and executed. Mathematics, engineering, and civil or house architecture, are sciences nourished and taught in our universities and other schools ; and to whatever degree of superiority scholars may arrive in these, shew them shipping draughts, or talk to them of the science of ship-building, and they appear as much at a loss as though they had never heard of such an art. This, however, is the picture of a few years ago ; it is now begun to be studied under the denomination of naval architecture ; for the promotion of this science, a very respectable body of ingenious men have, for the last fifteen years, associated.

In ship-building three things are necessary to be considered ; first, to give the vessel such a form as shall be best adapted for sailing, and for the service for which she is designed; secondly, to unite the several parts into a compact frame; and thirdly, to provide suitable accommodations for the officers and crew, as well as for the cargo, furniture, provisions, guns, and ammunition.

The outside figure of the ship includes the bottom, or the hold, and the upper- works,which are also called the dead-works; the first is that part which is generally under, the second are those which are usually above it when the vessel is laden.

To give a proper shape to the bottom of the ship, it is necessary to consider the service for which she is designed. A ship of war should be able to sail swiftly, and carry her lower tier of guns four or five feet out of the water; a merchant-ship ought to be able to contain a large cargo of goods, and to be navigated with few hands; both of these should be able to carry sail firmly,; to steer well , and to sustain the shocks of the sea without being violently strained.

Ships are built principally with oak-timber, which is the stoutest and strongest wood we have ; and, therefore, best fitted both to keep sound under water, and to bear the blows and shocks of the waves, and the terrible strokes of cannon-balls. For this last purpose it is a peculiar excellence of the oak, that it is not so liable to splinter or shiver as other wood, so that a ball can pass through it without making a large hole.

During the construction of a ship she is supported in the dock, or upon a wharf, by a number of solid blocks of timber, placed at
equal distances from, and parallel to, each other ; in which situation she is said to be on the stocks.

The first piece of timber laid upon the stocks, is generally the keel, which at one end is let into the stern-post, and at the other into
the stem. If the carcase of a ship be compared to the skeleton of a human body, the keel may be considered as the back-bone, and the timbers as the ribs.

The stern is the hinder-part of the ship, near which are the state-room, cabins, &c. To the stern-post is fixed the iron-work that holds the rudder, which directs the course of the vessel.

The stem is a circular piece of timber in the front ; into this the sides of the ship are inserted. The outside of the stem is usually
marked with a scale, or division of feet, according to its perpendicular height from the keel ; the intention of this is to ascertain the
draught of water at the fore-part, when the ahip is in preparation for a sea-voyage.

The caulking of a ship is a very important operation ; it consists in driving oakum, which is old ropes untwisted, and the substance pulled or beaten into loose hemp, into the seams between the planks, to prevent the ship's leaking. It is afterwards covered with
hot melted pitch or rosin, to prevent its rotting.

A mixture was formerly used for covering the bottom of ships, made of one-part of tallow, oue of brimstone, and three of rosin ;
this is called paying the bottom. The sides and bottom are now usually payed with coal tar, the produce of England.

To enable ships to sail well, the outsides in contact with the water are frequently covered with copper.

The masts of ships are made of fir or pine, on account of the straightness aud lightness of the wood. The length of the main-mast
of an East India ship is about eighty feet. The masts always bear a certain proportion to the breadth of the ship; whatever the breadth may be, multiply that by twelve, and divide the product by five, which will give the length of the main-mast. Thus, a ship which measures thirty feet at the broadest part, will have a main- mast seventy-two feet long; the thickness of the mast is estimated by allowing one inch for every three feet in length ; accordingly, a mast seventy-two feet long must be twenty-four inches thick. For the other masts different proportions are to be used. To the masts are attached the yards, sails, and rigging, which receive the wind necessary for navigation.

When a ship is finished building, it is next to be launched; that is, slipped off the stocks into the water. To render the operation of launching easy, the ship, when first begun to be built, is supported by two strong platforms, laid with a gradual inclination to the water. Upon the surface of this declivity are placed two corresponding ranges of planks, which compose the base of the frame, called the cradle, to which the ship's bottom is securely attached. The planes of the cradle and platform are well greased, and then the blocks and wedges, by which the ship was supported, are driven out from under the keel; afterwards the shores, by which she is retained on the stocks, are cut away, and the ship slides down into the water.

Ships of the first rate are usually constructed in dry docks, and afterwards floated out, by throwing open the flood-gates, and suffering the tide to enter, as soon as they are finished.

In a dock-yard where ships are built, six or eight men, called quartermen, are frequently entrusted to build a ship, and engage to perform the business for a certain sum, under the inspection of a master-builder. These employ other men under them, who, according to their different departments, will earn from fifteen or twenty shillings to two or three pounds per week.