form: but it was not until the advent of Haydn that its modern character was acquired. Under his genius first came classical models. The sonatas of Emanuel Bach were the starting point of Haydn's music. He worked out gradually the so-called art of free thematic treatment. Compared with the older style its chief features are greater freedom in developing the themes; the parts are not bound down to the rules of strict counterpoint; the melody is given chiefly to one voice, generally the upper. Free passages are introduced between the several melodic groups that make up the contrasted themes. A general air of lightness, grace, elegance and pleasantness is the result of this freedom of treatment. A whole movement is evolved out of little rhythmical motives or germs, which recur again and again, under ever changing conditions of melody, harmony, key, position or range, and instrumentation. By such kaleidoscopic changes the motives express constantly new meaning and beauty without abandoning the central idea of the piece. Then, too, each movement is polythematic instead of monothematic. Haydn in these and other respects prepared the way for Mozart and Beethoven, and neither of the three can be considered without the other. Mozart and Beethoven obtained the structural form and basis of instrumentation from Haydn; on the other hand, Haydn in his old age and Beethoven in his youth learned from Mozart a richer art of instrumental color and expressiveness, especially in the use of wind instruments. While Mozart did not enlarge the cyclical forms beyond the general outlines laid down by Haydn, he beautified and enriched them in all their details. In his last three symphonies and famous six quartets the beauty is more refined, the pathos more thrilling and profound, the dissonances and modulations more daring and fascinating. His music is conceived in a more serious vein. [Illustration: BEETHOVEN'S MONUMENT IN VIENNA. Executed by Zumbusch. From a photograph. (See page 332.)]