HORN, a musical instrument, commonly called in this country the French horn; in Italy. corn(); in France, con de chasse. Its form is that of a long tube of brass, with a large bell-shaped ending. For greater convenience the tube is coiled up into four con tinuous circles, lying side by side, the coils being solde:cd together, to keep them' in their position. It is sonnded by means of a mouthpiece, in form like a little hollow cup. The thinner the sheet-brass is, of which the horn is made, the more easily can the sound be produced. The sounds obtained on the horn are the harmonics of the sound of its whole length, a fundamental sound which cannot be produced by the mouth. As those sounds form only a limited scale, the notes awanting are artificially made, by the hand being inserted into the bell, so as to flatten a higher note down to a lower one. These flattened notes are called stuffed notes, as the sound of them is muffled. The horn, ;n its natural state, can only be played in one key; lint by means of crooks, which are added to increase the length of the tube, it can be transposed into any key. When at its greatest length, the horn measures, from the mouth-piece to the end of the bell, 16 feet. The music for the horn is always written in the key of C,
with the key of the composition marked at the beginning of each movement; thus, corno in I), etc., guides the performer as to the crooks he must use, in order to play the notes in the key indicated. The stuffed notes on the horn being very defective in quality of sound, in comparison with the great beauty of the open notes, many inven tions have been, from time to time, tried to remedy them. The most successful inven tion is the valve-born, which is constructed so that the performer can, by Incans or three valves, lengthen or shorten the tube, so as to produce nny note in the chromatic scale, as a harmonic of the length of the tube, and consequently all of the notes are of the same quality of sound, mid open notes. The valve-horn is now generally used as a solo instrument with greater effect than the common born. As an orchestral instrument, the horn is of great importance. There are never less than two horns in an instrumental score, and in many great works four horns are absolutely necessary. The date of the invention of the horn is lost in antiquity.