A Dictionary of Music and Musicians/Alpenhorn
ALPENHORN, or ALPHORN, an instrument with a cupped mouthpiece, of wood and bark, used by the mountaineers in Switzerland and many other countries to convey signals and to produce simple melodies. It is nearly straight, and three or more feet in length. Those in the Museum at South Kensington are respectively 7 ft. 5 in. and 7 ft. 11 in. long. There is a Swedish instrument of this kind called Lure; another of kindred nature used in the Himalayas; and another by the Indians of South America.
The notes produced are evidently only the open harmonics of the tube, somewhat modified by the material of which it is made, and by the smallness of the bore in relation to its length. The melody is termed 'Ranz des Vaches.' Its principal musical interest is derived from its introduction into the finale of Beethoven's Pastoral Symphony, and Rossini's opera of 'William Tell.' Beethoven employs the ordinary horn alone; but in the overture the long solo, now usually played by the oboe, sometimes by the cor anglais, was originally intended for, and played by, a tenoroon or alto fagotto standing in F, which much more nearly approaches the real tone of the Alpenhorn than the other instruments.
A similar combination of cupped mouthpiece with wooden tube existed in the serpent, and the result was a peculiar covered and tender quality of tone now lost to music, except in so far as it can be traced in some organ reed-stops, with wooden, not metal bells.