A Dictionary of Music and Musicians/Cor Anglais
COR ANGLAIS. (Ital. Oboe di Caccia; and Corno Inglese; Germ. Englisches Horn.) A tenor oboe, standing in the key of F, and therefore speaking a fifth lower than the ordinary oboe. It has the same scale and compass as the latter instrument, from E or E♭ in the bass, to about A or B♭ above the treble clef. It bears the same relation to the oboe that the bassethorn does to the clarinet, hence frequent confusion between the two instruments. It is probably similar in many respects to the 'oboe di caccia' found in Bach's scores, and perhaps to the 'chalumeau' of Glcck's operas; although the former was made in the form of a bassoon or alto-fagotto, and the latter may have been a kind of clarinet.
Beethoven has written a fine trio, Op. 29, for two oboes and cor anglais, and variations on 'La ci darem,' which though performed at Vienna on Dec. 23, 1797, are still in MS. Rossini employs it to represent the alpenhorn in the overture to 'William Tell' [App. p.597 "Oboe di Caccia, vol. ii. p. 489"]; Meyerbeer, Wagner, Halévy, Ambroise Thomas, and other modern composers frequently introduce it in their operas. It has a peculiar wailing and melancholy tone, which is very effective, but it is difficult and somewhat treacherous in the orchestra.[ W. H. S. ]