All known copies of the _Speculum_ contain a variety of dissimilar paper-marks. Among them are the hand, the dolphin, the lily, the unicorn, bulls’ heads, the letter P, the letter Y, the letters M A, the spurred wheel, and the papal keys. Many of these marks are found in the paper of the _Canticles_ and the _Bible of the Poor_. It is evident that papers bearing so great a variety of paper-marks were not made at one mill, and probably not in the same district. They were not made in Holland, at least not during the first half of the fifteenth century, for there were then no paper-mills in that country. The early records of the treasury of the city of Haarlem, which are written on papers containing paper-marks like those of the _Speculum_, show that the paper was bought at Antwerp. Koning thinks that the _Speculum_, and the block-books which are printed on the same paper, must have been printed between 1420 and 1440; that the paper of the books was made in Brabant; and that many of the paper-marks are the initials or arms of the house of Burgundy. According to Koning, the letter P stands for Philip the Good, Duke of Burgundy, who reigned from 1419 to 1467; the letter Y stands for Ysabella of Portugal, who married Philip in 1430; M A stand for Margaret, who was countess of Holland before that state was ceded to Philip in 1433. These are very confident assumptions; they require a careful examination. A closer investigation has elicited these facts: the letter P has been found in the accounts of the Count of Holland at the Hague for the year 1387; paper bearing the same P was used by many printers of the Netherlands, by one printer in Paris, and by several printers in Germany in the last quarter of the fifteenth century. It is found in paper made before and [p310] after the reign of Philip, and in cities over which Philip never ruled. Paper containing the letter Y was used in 1395, before Ysabella was born; it was in use for many years after she was dead; paper with the letters M A joined to the arms of Bavaria must have been made before her daughter Jacqueline was married, or, in other words, before 1422, an earlier date than can be claimed for any typographic book. The rude paper-mark of the bull’s head was in frequent use between the years 1370 and 1523 in the Netherlands and in Germany; it is found in the great Bible of Gutenberg. It is, therefore, of no value in an inquiry concerning the date of any book in which it has been found. The paper-mark of the lily was used even in the fourteenth century; in the fifteenth it was as common as the bull’s head. It is found in books that were printed in Cologne and in Paris, in Utrecht, Gouda, Delft, Louvain and Deventer. Paper marked with the unicorn was frequently used by the later Netherlandish printers. It did not go out of use until 1620. It is found in so many shapes that it is impossible to determine by it the date, or the printer, of any book on which it was used. [Illustration] [Illustration]