As has already been remarked, Scarlatti was the principal representative in the development of the form of the clavier sonata. Scarlatti, but a few years older than J. Sebastian Bach, has the same distinguishing marks as his great contemporary. He holds himself firmly to a clearly determined form, conditioned by musical laws. The principal difference between the two composers is that Scarlatti was inclined to make the brilliant technique which he possessed as virtuoso the real object of the composition, while in the case of Bach, even in things of lesser dimensions, introspection and artistic intensity manifested themselves. Nevertheless, the flowing and dazzling manner of writing which Scarlatti possessed and which was the result of his Italian temperament, must have often served Sebastian Bach as a model. Scarlatti's form inclines more toward that of the etude than of the true sonata. It was through Baldassare Galuppi (1706-1785), a pupil of Lotti and a very talented composer, that the piano sonata received characteristic expression. In his works after the manner of Corelli and Tartini, the display and passage work appeared only as a subordinate element. In comparing Galuppi's celebrated sonata in D major with similar works of Scarlatti, we perceive the great difference between the two masters. The sonata's greatest companion-piece, the symphony, also came into existence through the efforts of Italian musicians. The word sinfonia first appears with a very uncertain meaning. In general, it was used to mark the distinction between vocal and instrumental movements in cantatas, in sacred music, and, later, in opera. At the beginning of the seventeenth century we find the word used for the first time in large vocal works, and applied to interludes, ritornelle and preludes. This became the general custom when opera was introduced, and the short instrumental prelude was always entitled symphony. This last species of composition is, indeed, to be considered as the origin of our classical symphonic form. Not all the early operas had instrumental introductions, although Jacopo Peri himself made use of them. In his "Eurydice" there is a symphony for three flutes! Monteverde considerably enlarged the form, but seemed to find in it no characteristic expression of his ideas. At that time the form consisted of three parts, a slow movement, a quicker movement, and again a slow movement. This form of the symphony had really no artistic connection with the opera which followed, but was only a musical piece to inform the hearers that the performance was about to begin. Later, however, came works with more marked and pertinent character, which bore the names, overture and toccata. Finally, through the introduction of ballet-melodies, the symphony became of a livelier nature. At the same time, the word symphony gained more significance, and, as its inner construction kept pace with the modest beginning of the