[283] The vellum was not prepared in any way to receive the silver-point drawing; but when an artist wanted to make a finished study in silver-point he covered his vellum or paper with a priming of fine _gesso_, powdered marble, or wood-ashes; this gave a more biting surface to the paper, and made the silver rub off more easily and mark much more strongly. In the case of manuscript illuminations a strongly marked line was not needed, as the outline was only intended as a guide to the painter. [284] See above, pages 29 and 30, on the pens and inkstands of the classical scribes. [285] Usually meant for Saint Jerome translating or revising the Latin edition of the Bible. [286] Again, the first miniature in the French and Flemish _Horae_ usually represents _Saint John in Patmos_ writing his Gospel. The eagle stands by patiently holding the Evangelist's inkhorn. In some manuscripts the Devil, evidently in much awe of the eagle's beak, makes a feeble attempt to upset the ink. In the latest manuscript _Horae_ this scene is replaced by the one of _Saint John at the Latin Gate._ [287] A two-columned page of text had, of course, two sets of framing lines, one for each patch of writing. [288] In some manuscripts lines are ruled in blue or purple, but much less frequently than in the more decorative vermilion. [289] In certain classes of books, such as large Bibles and Prayer-books, the custom of ruling red lines lasted till the present century. [290] These guiding letters were used in all the early printed books which had initials painted in by an illuminator. [291] As a rule these manuscript signatures in printed books were written close to the edge of the page, and so have been cut off by the binder; in some tall copies, however, they still exist. [292] The next stage was the numbering of each _folio_ or leaf, and the last system was to number each page. Folios appear to have been first numbered in books printed at Cologne about the year 1470. A further modification has recently been introduced, namely, in two column pages, to number each column separately. [293] The _Lectionary_ mentioned on p. 120 was written and signed by a monastic scribe called Sifer Was. [294] Some fine examples of magnificently bound manuscripts are illustrated by Libri, _Monumens inédits_; _Hist. Ornam._ Paris, 1862-1864. [295] In Geyler's _Fatuorum Navicula_, of which many editions, copiously illustrated with woodcuts, were published shortly before and after the year 1500, the cut showing the first fool of the series, the Bibliomaniac, represents him surrounded with books, all of which are bound after this design.