In the Leipsic period, few organ chorals were composed by Bach, but each one of these is a master work of the musician. The forms are those of the Weimar chorals, but are on a comparatively colossal scale and the art of the composer has increased in corresponding measure. They were published in the year 1739, together with several choral fugues in the third part of his so-called "Clavier-Uebung"; in 1746 were issued five variations in canonic form upon the Christmas song: "Vom Himmel hoch, da komm ich her" ("From Heaven on high come I hither"). Bach's strong attachment for this artistic form, over which he had gained entire mastery in his youth, continued to the end. His last work, composed immediately before his death and dictated to Altnikol, was an organ choral. [Illustration: MONUMENT TO BACH IN PARK AT LEIPSIC. Reproduced from an old steel engraving.] In Bach's organ music of a freer style, it is easier than in the chorals to perceive the gradual approach to perfection. Here it is very evident that Pachelbel was not his master; even the few preludes and fugues which he wrote in his first years at Arnstadt betray a study of Buxtehude. After the journey to Lübeck, what had before been imitation became free creation after the manner of his model. In Weimar, where he rose to eminence as an organ virtuoso, the striving after external brilliancy and the desire of developing his skill as a performer in all directions, bear evidence for a considerable period of his continued adherence to the style of the Danish master. Although the compositions of this time are in no wise superficial, they yet stand far below his later works in solidity. By degrees, and evidently in consequence of close and persevering labor with the choral, Bach's melodies become much richer and more expressive. The study of Italian music, to which he devoted himself in Weimar, had the effect of imparting to his work greater clearness and finish, and his beautiful "_canzone_" for the organ is the direct result of that study. The name itself bears witness to the fact, since the Italians of the seventeenth century were accustomed to designate by this word the musical form which afterwards was called the fugue. In a group of organ compositions, which manifestly belong to the later Weimar period, Bach shows himself to have reached that eminence as a composer of fugues which only he was able to attain. The greatest skill in execution is everywhere presupposed, but nothing is sacrificed to this; the fugal themes are forms of a strongly accentuated type; in the management of the parts great restraint and system are displayed; the preludes also lose their extemporaneous character, are given a real theme and subjected to the rules of the contrapuntal style. The only organ passacaglio by Bach was composed at about this time. Well knowing that Buxtehude had excelled in this form he resolved to make an attempt in that direction, summoned