The clews of a sail are those parts which a "land-lubber" might call corners; i.e., the clews of the mainsail are four, and are situated at the junction of the luff and head of the sail, the outer-leach and head of the sail, the outer-leach and foot of the sail, and the luff and foot of the sail; the latter being also called the tack.
The mainsail, as will be observed, has also a series of regular lines crossing its surface. These are called reef-points, and consist of short, dangling pieces of small rope, sewed into the sail, and hanging down on either side, long enough, when the sail is lowered, to be fastened around the main-boom, and thus tie down the sail, making it smaller for rough weather, which is called "reefing." On the outer-leach, at the end of these rows of reef-points, are placed little iron rings, or cringles, as they are called, which are used to pass a rope through, called a reef-pennant, to haul the sail well out on to the boom when being reefed. The rope (a a) represents what is called the topping-lift, and is used to lower or hoist the main-boom, so as to make the sail set well in certain circumstances; or when the main-boom is out over the water on one side of the boat, when running before the wind, to "top it up" so as to keep it out of the water when the boat rolls. It is set up by means of a small pulley, the end of the rope coming inboard through a sheave in the boom, or one fastened to its side.
The jib has its luff, head, foot, and after-leach, the same as the mainsail, but, of course, has only three clews, being a triangular sail.
And what is defined about these sails will apply to all fore-and-aft sails.
The most important ropes, to which the attention of the reader is called, are the following:—
The main-sheet (l) is a long rope fastened to the main-boom, and controlling the action of the mainsail. According to the size of the boat, this sheet will be single, or rove through a series of blocks, to enable the helmsman to handle the sail. Upon the management of this sheet depends, in a great measure, the safety of all boat-sailing. Its perfect handling and adjustment call for the nicest skill; for its slightest movement changes the whole face of the canvas spread in the mainsail.
The jib-sheets (m) are fastened to the after-clew of the jib at the foot of the sail, and are led aft on both sides of the deck, so as to be within reach of the helmsman, or those sitting in the after-part of the boat. Like the main-sheet, they are used to confine and trim down the jib, each being used on the side on which it is desired to trim down the sail.
The outer-jib is controlled in the same manner, by two sheets, one being led aft on either side of the deck.
The mainsail is hoisted by means of two sets of ropes, called throat and peak-halliards (n).
These are fastened at the foot of the mast to cleats when the sail is hoisted; the throat-halliards, usually on the port side of the mast, and the peak-halliards, on the starboard side of the mast.