But the difference is not so much in phraseology as in the broader aspects of invention and method. The fundamental division lies, of course, in the character of the two men. Haydn, the simple, ingenuous peasant, whose moods range from sturdy humor to solid dignity; Mozart, the keen, vivacious, witty cosmopolitan, whose humor always tends to satire, but whose exalted moments are moments of soulful, subjective contemplation. His music is accordingly more epigrammatic, on the one hand, and of a deeper, rounder sonority, on the other. Mozart and Haydn first became acquainted with each other in 1780, when both had behind them long careers full of creative activity. It is significant, however, that practically all the works which to-day constitute our knowledge of them were created after this meeting, and neither their music nor the fact of their admiration for each other leaves any doubt as to the power and depth of their mutual influence. Mozart profited probably more in matters of technique and structure; Haydn in matters of refinement and delicacy. The complete list of Mozart’s works includes no less than twenty-one piano sonatas and fantasias (besides a number for four hands); forty-two violin sonatas; twenty-six string quartets; seven string quintets, several string duos and trios; forty-one symphonies; twenty-eight divertimenti, etc., for orchestra; twenty-five piano concertos; six violin concertos; and eighteen operas and other dramatic works, besides single movements for diverse instruments, chamber music for wind and for strings and wind, songs, arias, and ecclesiastical compositions of every form, including fifteen masses. But only a portion of these is of consequence to the music lover of our day; the portion which constitutes virtually the last decade of his activity. The rest, though full of grace and charm, has only historical significance. His piano sonatas, we have seen, followed the model of Schobert and, in some measure, of Emanuel Bach, but the style of these works, available to the amateur and valuable as study material, is more individual than that of either of the earlier masters and their musical worth is far superior. The first of them were written about 1774 for Count von Dürnitz, of Munich, and represent his contribution to the light, elegant style of the period. In some later ones he strikes a more serious note; dashing or majestic allegros alternate with caressing cantabiles, graceful andantes or adagios of delicious beauty and romantic expressiveness. The violin sonatas, though supposed to have been written chiefly for the diversion of his lady pupils (the instrument was still considered most suitable for feminine amusement), are full of beauty, strength, and dramatic expression.