Shortly afterward, a series of books printed entirely from wood engravings, called block-books, were issued. The most important of them were the _Apocalypsis, seu Historia Sancti Johannis_; the _Historia Virginis ex Cantico Canticorum_; and the _Biblia Pauperum_, the last containing representations of some of the principal passages of the Old and New Testaments, with explanatory texts. The illustrations seem to be drawn with a supreme contempt for perspective and proportion, but bear evidence of the draperies and hands and faces having been carefully studied. The above is a copy of one of the cuts in the _Apocalypsis_. It represents St. John preaching to three men and a woman, with the inscription: “_Conversi ab idolis, per predicationem beati Johannis, Drusiana et ceteri_,” (By the preaching of St. John, Drusiana and others are withdrawn from their idols.) The adjoining cut, from the _Biblia Pauperum_, is curious as showing the general manner of representing the creation of Eve during the fifteenth century. Both have the appearance of careful drawings “spoiled in the engraving.” Previous to the invention of movable types, whole books of text were also engraved on wood, and the impressions were evidently taken by rubbing on the back of the paper, instead of a steady pressure, as in the printing-press, the ink used being some kind of distemper colour. [Illustration] The wood to be engraved on is carefully selected, and cut up into transverse slices seven-eighths of an inch thick. This is done by circular saws, which are necessarily very rigid, so as to insure good even cuts. After being cut, the slices are placed in racks something like plate-racks, and thoroughly seasoned by slow degrees in gradually heated rooms. When sufficiently seasoned they are reduced to parallelograms of various sizes, the outer portion of the circular section near the bark being cut away, and all defective wood rejected; such, for instance, as knots, irregular grain, as that resulting from the position of branches, which are indicated by light-coloured markings in the wood, known in the trade as “comets,” from their resemblance in shape to those fiery bodies. They are softer than the surrounding wood, and consequently do not cut well with the graver; therefore much care and a practised eye are needed in selecting suitable wood. A section of boxwood almost always exhibits parts of widely different values; the more so as it deviates from the circle in form, for then the annual rings are compressed, and consequently closer on one side than on the other, the side with the wide open rings being usually far inferior in value to the denser and smaller side.