BACH Johann Sebastian (1685-1750). Preludes and Fugues for Forte-Piano in all tones, both major and minor by J. Seb. Bach dedicated to the Conservatory of Music by the Publisher. I. Part, containing 24 Preludes and 24 Fugues (Paris at ordinary addresses; in Bonn chés l'Editeur N. Simrock, [1801]); one oblong volume in-4, 97 pages (24 x 32 cm); original blue cardboard (back cover, title track on the top cover, rubbed edges; slight wetness and slight browning on the title; slight marginal defects on a few leaves). Rare first edition of the second book of the Well-Tempered Clavier, published before the first book. Engraved edition, each plate bearing the number 138 (except p. 7). It contains the 24 preludes and fugues of the second book, numbered I-XXIV (actually 25-48, BWV 870-893 ). The editions were published almost simultaneously by Simrock, Hoffmeister (in Leipzig) and Nägeli (in Zurich), the second book having appeared before the first before the I. Part" [Hoboken 97; Fuld, p.117; RISM B 497 ]. Stamp of André DELAPIERRE (1968) on the back cover.