Home >> British Encyclopedia >> Lanius to Longevity >> Ledum

Ledum

lee-way, ship, wind, handed, line and lee

LEDUM, in botany, a genus of the De. candria Monogynia class and order. Na tural order of Bicornes. Rhododendra, Jussieu. Essential character ; calyx five.. cleft ; corolla flat, five-parted; capsule five-celled, gaping at the base. There are three species, all natives of the North of Europe. These shrubs growing on mosses or bogs, where the roots spread freely, cannot be preserved in gardens, as least so as to thrive, but in a proper soil and a shady situation.

LEE, an epithet to distinguish that half of the horizon to which the wind is direct ed from the other part whence it arises, which latter is accordingly called to wind ward. This expression is chiefly used when the wind crosses the line of a ship's course, so that all on one side of her is called to windward, and all on the oppo site side to leeward; and hence " Lee side," all that part of a ship or boat which lies between the mast and the side farthest from the direction of the wind ; or that half of a ship which is pressed down towards the water by the effort of the sails, as separated from the other half by a line drawn through the middle of her length : that part of the ship which lies to the windward of this line is accord ingly called the weather-side. Thus, if a ship sail southward with the wind at east, then is her starboard, or right side, the lee.side ; and the larboard, or left, the weathe•-side.

LEE wall, or LEEWARD way, is the la teral movement of a ship to the leeward of her course, or the angle which the line of her way makes with tier keel when she is close hauled. This movement is pro duced by the mutual effort of the wind and sea upon her side, forcing her to lee ward of the line upon which she appears to sail, and in this situation her course is necessarily a compound of the two mo tions by which she is impelled. All ships are apt to make some lee-way; so that in casting up the log-book something must be allowed for lee-way. But the lee-way

made by different ships, under the same circumstances, will be different : and even the same ship, with different lading, and having inure or less sail on board, will make more or less lee-way.

However, the common allowances made for lee-way, are these : 1. If the ship be close hauled, has all her sails set, the water smooth, and a moderate gale of wind, she is supposed to make little or no lee-way. 2. If it blow so fresh, as to cause the small sails to be handed, it is usual to allow one point. 3. If it blow so hard, that the tops must be close reefed, the ship then makes about two points lee way. 4. If one topsail must be handed, it is common to allow two and three quarters, or three points lee-way. 5. When both topsails must be handed, they allow about four points lee-way. 6. When it blows so hard, as to occasion the fore-course to be handed, the allow ance is between five and a half and six points. 7. When both main and fore courses must be handed, then six, or six and a half points must be allowed for her lee-way. 8. When the mizen is handed, and the ship is trying a hull, she then makes her way good about one point be fore the beam, that is, about seven points lee-way.

Though these rules are such as are generally used, yet as the lee-way depends much upon the mould and trim of the ship, we shall here give the method of ascertaining it by observation. Thus, let the ship's wake he set by a compass in the poop, and the opposite rhumb is the true course made good by the ship ; then the difference between this, and the course given by the compass in the bit tacle, is the lee-way required. If the ship be within sight of land, the lee-way may be exactly found by observing a point on the land which continues to bear the same way ; for the distance between the point of the compass it lies on, and the point the ship capes at, will. e the lee-way.