The muse, Polyhymnia, soon emerged from the stage of childish stammering. Guittone di Arezzo taught her to fix her thoughts in indelible signs, and two centuries of training culminated in the inspired composers, Orlando di Lasso and Pales-trina. Of the gradual degradation of the operatic art as its forms became more elaborate and fixed; of the arbitrary transfer of absolute musical forms like the aria, duet, finale, etc., into the action of the opera without regard to poetic propriety; of the growing tendency to treat the human voice like any other instrument, merely to show its resources as an organ; of the final utter bondage of the poet to the musician, till opera became little more than a congeries of musico-gymnastic forms, wherein the vocal soloists could display their art, it needs not to speak at length, for some of these vices have not yet disappeared. In the language of Dante's guide through the Inferno, at one stage of their wanderings, when the sights were peculiarly mournful and desolate-- "Non raggioniam da lor, ma guarda e passa." The loss of all poetic verity and earnestness in opera furnished the great composer Gluck with the motive of the bitter and protracted contest which he waged with varying success throughout Europe, though principally in Paris. Gluck boldly affirmed, and carried out the principle in his compositions, that the task of dramatic music was to accompany the different phases of emotion in the text, and give them their highest effect of spiritual intensity. The singer must be the mouthpiece of the poet, and must take extreme care in giving the full poetical burden of the song. Thus, the declamatory music became of great importance, and Gluck's recitative reached an unequaled degree of perfection. The critics of Gluck's time hurled at him the same charges which are familiar to us now as coming from the mouths and pens of the enemies of Wagner's music. Yet Gluck, however conscious of the ideal unity between music and poetry, never thought of bringing this about by a sacrifice of any of the forms of his own peculiar art. His influence, however, was very great, and the traditions of the great _maestro's_ art have been kept alive in the works of his no less great disciples, Mehul, Cherubini, Spontini, and Meyerbeer.