It will be only necessary, however, in this place to refer to the fact that the beautiful example in the Imperial Library at Vienna--which, from its spotless purity, Heineken calls the “exemplaire vierge”--differs from the others in being without the shield of Fust and Schoeffer, a fact which points to the probability of this copy having been the first struck off. By the end of the fifteenth century the Printer’s Mark had assumed or was rapidly assuming an importance of which its original introducers had very little conception. Indeed, as early as 1539, a law, according to Dupont, in his “Histoire de l’Imprimerie,” was passed by which these marks or arms of printers and booksellers were protected. Unfortunately the designs were very rarely signed, and it is now impossible to name with any degree of certainty either the artist or engraver, both offices probably in the majority of cases being performed by one man. There is no doubt whatever that Hans Holbein designed some of the very graceful borders and title-pages of Froben, at Basle, during the first quarter of the sixteenth century, and in doing this he included the graceful Caduceus which this famous printer employed. It does not necessarily follow that he was the original designer, although he was in intimate association with Froben when the latter first used this device. The distinctive Mark of Cratander, or Cartander, which appears in the edition of Plutarch’s “Opuscula,” Basel, 1530, has also been confidently attributed to the same artist: if there is any foundation for this statement Holbein was guilty of plagiarism, for this Mark is a very slight modification on one used by the same printer in 1519, and not only so dated but having the artist’s initials, I. F. Those who have the opportunity of examining the “Noctes Atticæ” of Aulus Gellius, printed by Cratander in 1519, will come upon several highly interesting features in connection with this Mark, which is emblematical of Fortune: the elaborately engraved title-page contains an almost exact miniature of the same idea on either side, and it is repeated in a larger form in the border which surrounds the first chapter. The Mark occurs in its full size on the last page of all. The title-page, borders and Mark are all by the same artist, I. F. In the earlier example the woman’s hair completely hides her face, whilst in that of eleven years later it is as seen on the opposite page, and the whole design is more carefully finished. Dürer had dealt with the same subject. In reference to Froben, however, it should be pointed out that his Marks, of which there were several, show considerable variation in their attendant accessories, and that Holbein could not possibly have had anything to do with the majority of them. [Illustration: J. FROBEN. γίνεσθε φρόνιμοι ὥς ὁι ὄφεις, Prudens simplicitas amor[que] recti.]