Gius. Tibaldi, whom Gluck had summoned to Vienna, where in 1767 he sang the part of Admetus[9] in "Alceste," was already in years, and his voice past its prime; his two songs (6, 19) are adorned with long passages, which imply a very fluent singer. In the closing terzet (21) the voices are at first contrasted in detached characteristic motifs; but afterwards the soprano and tenor are grouped together with alternating passages, while Manzuoli's part retains its simplicity of character. Of the two secondary characters, to each of whom two songs were assigned, it is to be noted that they have a higher compass than the principal singers. Their songs, too, are richly provided with passages; but their character is perceptibly subordinate. The choruses, seven in number, were a great ornament to the piece. They do not interfere with the action, and five are in connection with dances. Also in the overture, on the conclusion of the first animated allegro, the second movement changes into a dance "of eleven females," as L. Mozart writes, "either eight nymphs and three graces, or eight graces and three goddesses," and instead of the third {"ASCANIO IN ALBA"--CHORUSES.} (189) movement[10] a chorus of nymphs and graces with corresponding ballet is introduced, the orchestra retaining the character of a third movement of the overture, and the voices (four or two-part) filling out the harmonies after the manner of wind instruments, but in a freer, more flowing style. The chorus is repeated on both occasions when Venus ascends to heaven. Most of the other choruses are also repeated like refrains on appropriate occasions; the second (3) is given six times. It is in two parts, for tenor and bass, and remarkable for its accompaniment of 2 flutes, 2 oboes, 2 bassoons (and violon-celli), 2 horns, and double-bass, but not otherwise original. The following chorus (5), introduced by a short intrada, which announces Silvia's approach (four-part, but interrupted by two short three-part movements) is blithe and animated. The accompaniment has an independent passage in dance-measure for the violins; the voices move with spirit and freedom. The second act begins with two female choruses. The first, two-part (12), acquaints Silvia of the approach of her lover, and is lively and fresh; the two voices alternate easily in imitative phrases. Still more animated is the next three-part chorus (17), when, Silvia having repulsed Ascanio and fled, the chorus express surprise in a short imitative movement addressed to Venus. The following chorus (20), which is repeated three times, has simple harmonies, but is powerful and effective. The concluding chorus (22) is effectively worked up after the manner of the first into a quick animated movement, followed by a full ballet.