The date of this famous letter was 1767, but after Alceste Gluck was still able to use material from earlier work; and the overture to Armide is adapted from that of Telemacco, written in the year of Bach's death (1750).
In the new art the concentration of attention upon form, as a more important source of dramatic interest and climax than texture, resulted in a neglect of polyphony which seriously damaged even Gluck's work, and which always had the grave inconvenience that while the new methods of blending and contrasting instruments stimulated an increase in the variety, if not in the size of orchestras, there was at the same time extreme difficulty in finding occupation for the members of the lower middle class of the orchestra in ordinary passages.
Least of all can it conduce to the formation of sound critical standards for the new instrumentation which is now in process of development for the future forms of instrumental music. These, we cannot doubt, will be as profoundly influenced by Wagner as the sonata style was influenced by Gluck.
This Agricola was a pupil of Bach, and a fine organist and clever writer on music, especially on operatic style, the problems of which were beginning to be raised by French writers and composers in preparation for the work of Gluck.
As a complete fusion between dramatic and musical movement, its very crudities point to its immense advance towards the solution of the problem, propounded chaotically at the beginning of the i 7th century by Monteverde, and solved in a simple form by Gluck.
