by the critics, and secured the favour and adherence of the public by an unbroken series of works: whoever ventured on the same field was obliged to serve under his banner. The widespread popularity of quartet music in Vienna could not fail to impel Mozart to try his forces in this direction. His master was also his attached friend and fellow-artist, with whom he stood in the position, not of a scholar, but of an independent artist in noble emulation. The first six quartets belong to the comparatively less numerous works which Mozart wrote for his own pleasure, without any special external impulse. They are, as he says in the dedication to Haydn, the fruit of long and earnest application, and extended over a space of several years. The first, in G major (387 K.), was, according to a note on the autograph manuscript, written on December 31, 1782; the second, in D minor (421 K.), in June, 1783, during Constanze's confinement (Vol. II., p. 423); and the third, in E flat major (428 K.), belongs to the same year. After a somewhat lengthy pause he returned with new zeal to the composition of the quartets; the fourth, in B flat major (458 K.), was written November 9, 1784; the fifth, in A major (464 K.), on January 10; and the last, in C major (465 K.), on January 14, 1785. It was in February of this year that Leopold Mozart paid his visit to Vienna. He knew the first three quartets, Wolfgang having sent them to him according to custom; and he heard the others at a musical party where Haydn was also present; the warmly expressed approbation of the latter may have been the immediate cause of Mozart's graceful dedication, when he published the quartets during the autumn of 1785 (Op. ü).[3] The popular judgment is usually founded on comparison, and a comparison with Haydn's quartets was even more obvious than usual on this occasion. The Emperor Joseph, who objected to Haydn's "tricks and nonsense" (Vol. II., {MOZART AND KLOPSTOCK.} (3)