ALTITUDE. The elevation of any of the heavenly bodies above the plane of the horizon, or its angular distance from the horizon, measured in the direction of a great circle passing through the zenith. Also the third dimension of a body, considered with regard to its elevation above the ground.--_Apparent altitude_ is that which appears by sensible observations made on the surface of the globe.--_Altitude of the pole._ The arc of the meridian between the pole of the heavens and the horizon of any place, and therefore equal to its geographical latitude.--_Altitude of the cone of the earth's and moon's shadow_, is the height of the one or the other during an eclipse, and is measured from the centre of the body.--_Altitude of a shot or shell._ The perpendicular height of the vertex of the curve in which it moves above the horizon.--_Meridian altitude._ The arc of the meridian,--or greater or less altitude, measured from the horizon, of a celestial object in its passage over the meridian, above or below the pole, of the place of the observer. In Polar regions two such transits of the sun, and in England similarly, circumpolar stars afford double observations for the determination of time or latitude. The general term is understood by seamen to denote mid-day, when the passage and meridian altitude of the sun affords the latitude.--_True altitude_ is that produced by correcting the apparent one for parallax and refraction. ALTMIKLEC. A silver Turkish coin of 60 paras, or 2_s._ 9-1/2_d._ sterling. ALUFFE, OR ALOOF. Nearer to the wind. This is a very old form of _luff_; being noticed by Matthew Paris, and other writers, as a sea-term. (_See_ LUFF.) ALURE. An old term for the gutter or drain along a battlement or parapet wall. ALVEUS. A very small ancient boat, made from the single trunk of a tree. A monoxylon, or canoe. A.M. The uncials for _ante-meridian_, or in the forenoon. (_See_ MERIDIAN.) AMAIN [Saxon _a_, and _mægn_, force, strength]. This was the old word to an enemy for "yield," and was written _amayne_ and _almayne_. Its literal signification is, with force or vigour, all at once, suddenly; and it is generally used to anything which is moved by a tackle-fall, as "lower amain!" let run at once. When we used to demand the salute in the narrow seas, the lowering of the top-sail was called _striking amain_ (_see_ STRIKE), and it was demanded by the _wave amain_ (_see_ WAVING), or brandishing a bright sword to and fro. AMALPHITAN CODE, the oldest code of modern sea-laws, compiled, during the first Crusade, by the people of Amalfi in Italy, who then possessed considerable commerce and maritime power. AMAYE. Sea-marks on the French coast. AMBASSADOR. A practical joke performed on board ship in warm climates, in which the dupes are unmercifully ducked in the wash-deck tub:-- "And he was wash'd, who ne'er was wash'd before."