The Catechism Choral Preludes (in Clavierübung, Part III.) (bk. 16) (1739). Fugue in D minor (in ditto) (bk. 16 p. 49) (1739). Prelude and Fugue in E flat major (in ditto) (bk. 6 p. 28) (1739). Do. do. the “Great,” in C major (bk. 9 p. 156). Do. do. the “Great,” in B minor (bk. 7 p. 52) (1727-36). Do. do. the “Great,” in E minor (bk. 8 p. 98). Canonic Variations on “Vom Himmel hoch” (bk. 19) (1746). The Schübler Choral Preludes (bk. 16) (c. 1747-50). The Eighteen Choral Preludes (bk. 17) (c. 1747-50). The Musical Offering (P. bk. 219) (1747). The Art of Fugue (P. bk. 218) (1749). APPENDIX II. THE CHURCH CANTATAS ARRANGED CHRONOLOGICALLY We have the statement of Carl Philipp Emmanuel Bach,(346) confirmed by Forkel,(347) Bach’s earliest biographer, that his father composed five Cantatas for every Sunday and Festival of the ecclesiastical year. Concerted music was sung at Leipzig annually on forty-three Sundays and sixteen week-days.(348) Bach therefore must have written at least 295 Cantatas. Of this number he composed at least thirty before 1723. Hence approximately 265 were written at Leipzig. But Bach’s fertility does not appear to have outlived the year 1744. We have reason, therefore, to conclude that the 265 Leipzig Cantatas were written in the course of twenty-one years, that is, between 1723 and 1744. To complete that number Bach must have composed a new Cantata every month, a surprising but demonstrable conclusion. Of the 295 Cantatas only 202 have come down to us, three of them in an incomplete state.(349) Of those written before 1723 the survivors are too scanty to indicate a rate of productivity. But thereafter we have fuller materials for a calculation. Bach, as Cantor, conducted his first Leipzig Cantata on May 30, 1723, and in the following sixteen months produced twenty-four Cantatas, at the rate of more than one a month.(350) Beginning at the New Year of 1725 he wrote eighteen Cantatas in nine months, some of which, however, may belong to the years 1726-7-8-9. But even so, his monthly average seems to have been maintained. For 1730 we have, perhaps, ten Cantatas. For 1731 about twenty survive, of which half a dozen may belong to 1732, a deduction which still preserves Bach’s steady average. In 1735 he produced actually nineteen Cantatas between the New Year and the following November, though not all of them are positively dated. Thereafter his activity is less certainly measured. But from 1736 till the end of 1744 he composed fifty-three Cantatas, at the rate, that is, of at least six every year, without making allowance for Cantatas written and lost.