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CHAPTER I.

THE SHIP.

GENERAL REMARKS ON THE HULL, SPARS, AND SAILS.-DEFINITIONS.

Ships are usually built on stocks and launched on ways, which are inclined planes leading to the water's edge. Sometimes vessels are built in docks, which are artificial basins with level floors, shut off from outside waters by gates, or by a single dam, known as a caisson. These gates are water-tight and can be opened or closed; the dock is supplied with means for pumping out the water, or letting it in. The following is an outline of the principal parts of the hull of a wooden ship.

The lowest fore and aft piece which forms the foundation of a ship is called the keel (Plate I, No. 1). It is of live-oak, or elm, and made of several pieces, the joints of which are known as scarphs.

To receive the edge of the first row, or strake, of outside planking, called the garboard strake (2), the keel is scored throughout its length, the score being styled a rabbet (3).

To protect the main keel from injury in grounding there is fitted under it a false keel (4), bolted on after the bolts which secure the frames to the main keel are clinched.

The forward end of the ship is formed of the stem (5), usually of live-oak, and inclining forward from the keel. A rabbet, similar to the one scored in the keel, is cut into the sides of the stem and receives the forward ends of the outside planking, which are called the fore hood-ends.

The stem is backed and strengthened by the apron (6), placed abaft it, and by the deadwood (7).

Deadwood consists of timbers that fill the spaces where, owing to the shape of the vessel, the floor-timbers have to be discontinued.

Inside of the forward deadwood and the apron is the stemson (8), a large knee which joins the apron to the upper part of the deadwood.

The after-end of the ship is bounded by the stern-post (9), usually of live-oak, which stands perpendicular to the keel or slightly inclined aft. It is fitted like the stem with a rabbet on each side to receive the after-ends of the out. side planking, or after-hoods, and it is strengthened by the introduction of a stern-post knee (10), inner post (11), and the after-deadwood (12). Above the latter is the afterdeadwood knee (13).

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Screw vessels have generally two stern-posts; the after one, which carries the rudder, is called the rudder-post. The joining of the stern-post to the keel is effected by tenons and bolts.

The frames (14) form the ribs of the ship. They stand mostly at right angles to the keel and each is formed of two parts joined together, each part being in itself made up of several pieces. The lowest portions of a square frame are called the floor-timbers; above these come the futtocks, then the long or short top-pieces. The starboard and port side of each frame form one continuous piece.

Where, owing to the form of the ship, the frames do not stand at right angles to the keel, they are called cant frames.

The following parts of the ship serve to secure the above-mentioned portions together and give the structure stiffness and strength; viz., the keelsons, breast-hooks (15) and stern-hooks (16), outer and inner planking, beams (17) and diagonal braces.

The main keelson (18) is a fore and aft timber which is laid directly over the keel on the floor-timbers and may extend beyond the latter and over the deadwood, forward and aft. The keelson is bolted through frames, keel, and deadwood. There are usually additional keelsons at each side of the main keelson, known as sister keelsons (20). There are also boiler or bilge keelsons to support the boilers (19). Bilge-keels are exterior keels bolted on to the bottom of the ship on either side of, and parallel to, the main keel, and at some distance from the latter, to prevent rolling in vessels of certain form.

To hold the two sides of the ship together in the forward and after ends, where the frames have no floor-timbers crossing the keel, owing to the form of the ship, there are worked in knee-shaped, horizontal timbers, either with a natural curve, or formed of two or more pieces backed by an iron or wooden knee. These curved supports, secured to either side of the ship, are termed breast-hooks (15) forward and stern-hooks (16) aft; when they support a deck they are called deck-hooks.

The outer planking of a ship is formed of a number of oak planks of varying thickness, but nearly parallel when placed in position over the frames.

To check marine growth on the bottom of vessels and the consequent decrease of speed, all wooden vessels of war are sheathed with copper from the keel to a point some distance above their line of flotation, or "water-line."

The inner planking is not continuous, as in the case of outside planking, and in different parts of the ship is called by different names. It is known as the limber-strakes (21) nearest the keelson. These strakes extend along the bottom of the ship on either side of the keelson. As the planking is carried up the side beyond the

limber-strakes it is known as the ceiling (22); following it up higher we find projecting ledges, called shelf-pieces, or clamps, placed inside the frames to receive the deckbeams.

The deck-beams (17), extending from side to side of the ship, holding the sides together, form the support for the deck-planking. The beams are supported by posts or stanchions (23) in their centre, and by clamps at each end. They are joined to the sides of the ship by iron or wooden knees, known as hanging (24), lodging (25), lap (26), or dagger (corruption of diagonal) knees, from their positions and form.

The waterways (27) are timbers set in the side over the tops of the deck-beams and bolted to these and to the frames at the side.

Decks are of oak, teak, or yellow pine, and are spiked to each deck-beam over which they pass.

Vessels owe much of their strength to the use of diagonal trusses or braces, of metal, secured inside of the frametimbers and forming a net-work which binds the frames firmly together.

To the above outline of the parts of the hull is appended a list of prominent interior fittings and of the terms used in describing them. As will be seen, some apply only to wooden ships; and some to both wooden and iron ships alike.

Aft. At or near the stern of the ship.

After passage. Usually a space in the after orlop of frigates, being a passageway to the different store-rooms on that deck.

Air-port. Hole cut in ship's side to give light and air to berth-deck. Usually

circular.

Amidships. In or near the middle of the ship.

Apron. A timber secured in rear of the stem to strengthen it at the joint of upper and lower stem-pieces.

Athwartships. In the direction of the ship's breadth.

Bag-room. Where clothing-bags of crew are stored. Usually forward on the berth-deck or leading off of fore-passage.

Ballast. Stone or iron placed in the hold to bring the ship down to her proper line of flotation and give stability.

Beams. Timbers that extend from side to side, supporting the decks.
Bee-blocks. Clamps bolted to the bowsprit through which reeve the fore-top-

mast stays.

Belaying-pin. A pin of wood or metal at the side of the vessel or on the masts, around which a rope is fastened or belayed

Bends. The thickest outside planking, extending from a little below the waterline to the lower gun-deck ports.

Berth-deck. The sleeping and mess-deck of the crew and officers of a ship. Bibbs. Pieces of timber on either side of the mast to which the trestle trees are secured, and upon which they rest.

Bilge. The flat part of a ship's body on each side of the keel.

Bilge-keels. Long pieces of wood or iron affixed to ship's bottom to lessen the rolling motion.

Bill-board. A ledge on the ship's bow to receive the fluke of the anchor. Binnacle. The case mounted on a stand in which the compass is carried when

in use.

Bitts. Large vertical timbers projecting above the deck to secure the ship's cable, also vertical posts to secure the main-tack, main-sheet, etc., according to location.

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