Only seven copies of the Psalter of 1457 are known, and they are all printed on vellum. Although they have all the same colophon, containing the printers’ names and the date, yet no two copies exactly correspond. A similar want of agreement is said to have been observed in different copies of the Mazarine Bible, but which are, notwithstanding, of one and the same edition. As such works would in the infancy of the art be a long time in printing--more especially the Psalter, as, in consequence of the large capitals being printed in two colours, each side of many of the sheets would have to be printed thrice--it can be a matter of no surprise that alterations and amendments should be made in the text while the work was going through the press. In the Mazarine Bible, the entire Book of Psalms, which contains a considerable number of red letters, would have to pass four times through the press, including what printers call the “reiteration.”[IV-1] [Footnote IV-1: By the common press only one side of a sheet can be printed at once. The reiteration is the second printing of the same sheet on the blank side. Thus in the Psalter of 1457 every sheet containing letters of two colours on each side would have to pass six times through the press. It was probably in consequence of printing so much in red and black that the early printers used to employ so many presses. Melchior de Stamham, abbot of St. Ulric and St. Afra at Augsburg, and who established a printing-office within that monastery, about 1472, bought five presses of John Schüssler; a considerable number for what may be considered an amateur establishment. He also had two others made by Sixtus Saurloch.--Zapf, Annales Typographicæ Augustanæ, p. xxiv.] The largest of the ornamented capitals in the Psalter of 1457 is the letter B, which stands at the commencement of the first psalm, “Beatus vir.” The letters which are next in size are an A, a C, a D, an E, and a P; and there are also others of a smaller size, similarly ornamented, and printed in two colours in the same manner as the larger ones. Although only two colours are used to each letter, yet when the same letter is repeated a variety is introduced by alternating the colours: for instance, the shape of the letter is in one page printed red, with the ornamental portions blue; and in another the shape of the letter is blue, and the ornamental portions red. It has been erroneously stated by Papillon that the large letters at the beginning of each psalm are printed in three colours, red, blue, and purple; and Lambinet has copied the mistake. A second edition of this Psalter appeared in 1459; a third in 1490; and a fourth in 1502, all in folio, like the first, and with the same ornamented capitals. Heineken observes that in the edition of 1490 the large letters are printed in red and green instead of red and blue.