musical instrument, varying in form and in quality of sound. Each horn has a cup-shaped mouth-piece, by blowing into which, with a particular management of the lips, the sounds are produced. The ancient coronets, of different sizes, straight-shaped, formed of wood, &c., need not be described here, as they are disused. The common hunting-horn is of copper or brass, and bent into a semi-circle. The French horn is made of brass, and consists of a tube bent into circular convolutions, and terminating in an expansion of the tube, called the bell or pavilion. There are generally two French horns used in orchestras, or in military bands,—a first and a second horn,—and these are furnished with crooks which alter the length of the tube, so as to adapt the horns to the different keys of the music to be played. The natural or open sounds follow the harmonic progression 1, 2, 3, 4, 5, 6, 7, &c.; but by placing the hand, or a cone of pasteboard, within the bell, the intermediate tones and semitones may be produced, and a scale formed, more or less pure and accurate. (See Music, § Horn.) Finger-keys were at one time applied to some horns, but have been superseded by pistons. The old bugle-horn is now the pistoned cornet or cornopean. Of late years, C. J. Sax of Brussels has greatly improved all instruments of the horn kind, as well as flutes, clarinets, &c. The German bass-horns are made of wood, and have finger-holes and finger-keys. The basset-horn and the English horn are not really horns, the former being only a large clarinet, and the latter a large oboe, with some peculiarities of form. See Appendix to G. F. Graham's Essay on Musical Composition, Edin. 1838.

Hoorn, Cape, commonly considered the southern extremity of America, is not a part of that continent, but the most southerly point of a small island of the Tierra del Fuego group; S. Lat. 56. 58. 40., W. Long. 67. 16. It consists of a lofty, precipitous, bare black rock, running far out into the sea; and was formerly considered dangerous to pass on account of the strong westerly gales that prevail in its neighbourhood during summer, but as these are restricted to the vicinity of the cape, vessels avoid the difficulty by sailing in a higher latitude. It was discovered in 1616 by the Dutch navigator Schouten, who named it after his native town, Hoorn.

HORNCastle, a market-town of England, county of Lincoln, on the Bain, a tributary of Witham, and navigable to this point, 18 miles E.S.E. of Lincoln. It was an ancient Roman station, and traces of its old walls still exist, Roman coins and other antiquities have also been discovered in the vicinity. A considerable trade is carried on by means of the river. Horncastle has a grammar school, mechanics' institute, library, literary society, and a savings bank. The market-day is Saturday; and one of the largest horse fairs in the kingdom is held here in August. Pop. (1851) 4921.