The only block-book without pictures of which we have any knowledge is the _Donatus_,[128] or _Boy’s Latin Grammar_. It received its name from its author, Ælius Donatus, a Roman grammarian of the fourth century, and one of the instructors of St. Jerome. The block-book is but an abridgment of the old grammar: as it was usually printed in the form of a thin quarto, it could, with propriety, be classified among primers rather than with books. When printed in the largest letters, it occupied but thirty-four pages; when letters of small size were used, it was compressed within nine pages. As the most popular of small works, and one constantly needed in every [p255] preparatory school, it met the conditions then required by the early publisher: it could be engraved at little cost, and the printed copies could be sold in very large quantities. How many xylographic editions of the book were printed has never been ascertained, but we are led to believe that the number was large when we learn that more than fifty editions were printed from types before the year 1500. Fragments of the xylographic _Donatus_ are scarce, and they are, for the most part, in a shabby condition. Many of them are the remnants of badly printed leaves which were rejected as spoiled by the printer. If it had not been for the frugal habits of the binders, who used them as stiffeners in the covers of books, we should have few specimens of this book. These waste leaves were put to this use because they were printed on parchment and had more strength than paper. And here we have to notice a remarkable difference between the block-books of images and the xylographic _Donatus_. All the block-books are printed on paper, and the greater part are printed on one side of the sheet in brown ink. All copies of the xylographic _Donatus_ are printed on parchment, on both sides of the leaf, and in black ink. Parchment was, no doubt, selected to adapt the book to the hard usage it would receive from careless school-boys, but the method of printing in black ink and on both sides is the typographic method, which was not in use, so far as we can learn, before the middle of the fifteenth century. We have to conclude that all copies of the _Donatus_ printed in this manner were printed after the invention of types. The most trustworthy authorities say that there is no known fragment of an engraved _Donatus_ that can be attributed to the first half of the fifteenth century.