Scriverius said that Lourens Janszoen or Laurens Koster was the inventor of xylography as well as of types. After an examination of the _Speculum_, he had wit enough to see what Junius did not, that the printer of the book must have had practice with blocks, and that printing on blocks necessarily preceded printing with types. His description of the growth of the new art is not at all satisfactory. The careless manner in which he skips over the invention of matrices and the making of the moulds is that of a man who knows nothing [p350] about type-founding, neither from instruction nor observation. Encouraged by the praise which Scriverius had received for his performance, Marcus Zuerius Boxhorn undertook to place the date of the invention eight years earlier. In his _Dissertation on the Invention of Typography_, printed by Vogel at Leyden in the year 1640,[206] Boxhorn says that the invention was made in 1420. Here we encounter a curious fact. The story of Junius had been published less than fifty years, yet the writers disagreed concerning the date of the invention. Believers in the legend had been taught by one teacher that typography was invented in 1440—by another, in 1428—by another, in 1420. And it is a noticeable circumstance that the authors farthest removed from the date of the invention were the most positive in their statements. The later writers, who knew the least, give us the earlier dates. Adrien Rooman, a printer of Haarlem, and apparently a conservative and conciliatory man, thought that these differences could be most satisfactorily adjusted by fixing the date midway between the extremes. He was not in the possession of any newly discovered facts, and had no authority for the arbitrary selection, but this incompetency did not prevent him from publishing a portrait of Coster, with an inscription which made the year 1430 the date of the invention. To the thinking men of Haarlem the assumptions of Boxhorn were as unsatisfactory as those of Junius and Scriverius. There was an air of improbability, or at least of uncertainty, about the statements of all the authorities, which filled their minds with doubts as to the truth of the legend. The statue to Coster, which was soon after put up in the Doctors’ Garden, had no date of invention on the pedestal. To remove these doubts, Seiz[207] undertook, in 1742, to furnish “a true and rational account of the invention” by Coster. The truth and reason of this new description of the invention of Coster are most strikingly illustrated in its chronology. [p352] [Illustration: The Statue of Coster in the Doctors’ Garden. [From Seiz.]] 1428 Laurens Coster engraved a few letters upon the bark of a tree. 1429 He gave one year to experimental engraving on wood. 1431 He printed the _Temptations of Demons_ or _Ars Moriendi_. 1432 Printed the _Bible of the Poor_. 1435 He began to engrave and print an edition of the _Donatus_. 1436 He cut separate letters or single types out of lead.