The conjecture put forward by M. Dziatako, that Gutenberg may have printed the thirty-six line Bible in partnership with some other printer, as, for example, Pfister, would certainly, if any proof in its favour could be adduced, simplify matters very much. We should then have all the books in a natural sequence, from the Bible to the latest books of Pfister, and we could account for the printing of the _Manung_ in 1454, while Gutenberg was still in partnership with Fust and Schœffer for the production of the forty-two line Bible. The workmanship of the thirty-six line Bible is in some points different from the later books, all of which were probably the work of Pfister, who, according to this theory, must have been at work at Mainz as early as 1454. The contract between Gutenberg and Fust did not necessarily bind the former to print only with Fust, so that he may also have worked with Pfister, and taught him the art. Pfister’s last dated book, _The Histories of Joseph, Daniel, Judith, and Esther_, was printed in 1462, not long after the day of St. Walburga (May 1). After this time we hear of no book printed at Bamberg till 1481, when John Sensenschmidt printed the _Missale Ordinis S. Benedicti_, commonly known as the Bamberg Missal. Cologne, from its situation on the Rhine, was in a favourable position for receiving information and materials from Mainz, and we find that by 1466, Ulric Zel of Hanau, a clerk of the diocese of Mainz, was settled there as a printer. His first dated book was the Chrysostom _Super psalmo quinquagesimo_; but some other books were certainly issued before it. The Cicero _De Officiis_, a quarto with thirty-four lines to the page, is earlier, and is perhaps the first book he issued. It has many signs of being a very early production, and may possibly have been issued before Schœffer’s edition of 1465.