and patience. Where or when or by whom these block-books, as they are called, were first engraved and printed is unknown; these questions have been bones of contention among antiquarians for three hundred years, and in the dispute much patient research has been expended, and much dusty knowledge heaped together, only to perplex doubt still farther, and to multiply baseless conjectures. It is probable that they were produced in the first half of the fifteenth century, when the men of the Renaissance, whose aroused curiosity made them alert to seize any new suggestion, were everywhere seeking for means to overthrow the great barrier to popular civilization, the rarity of the instruments for intellectual instruction; they soon saw of what service the new art might be in this task, through the cheapness and rapidity of its processes, and they applied it to the printing of words as well as of pictures.
The most common manuscripts of the time, which had hitherto been the cheapest mode of intellectual communication, were especially fitted to be reproduced by the new art; they were those illustrated abridgments of Scriptural history or doctrine, called Biblia Pauperum, or books of the poor preachers, which had long been used in popular religious instruction, in accordance with the mediæval custom of conveying religious ideas to the illiterate more quickly and vividly through pictures than was possible by the use of language alone. In the sixth century Gregory the Great had defended wall-paintings in the churches as a means of religious instruction for the ignorant population which then filled the Roman provinces. In a letter to the Bishop of Marseilles, who had shown indiscreet zeal in destroying the pictures of the saints, he wrote: "What writing is to those who
