Nothing more was said on the subject that night, but Anna could see, as day followed day, that her husband was planning something, and she felt very certain that he was thinking out a way of making books more quickly than by the old process of copying them word for word by hand. A few weeks later the young lapidary surprised his wife by showing her a pile of playing-cards. “See my handicraft,” said he. “Aren’t these as good as the Knave of Bells I gave thee?” She looked at them, delight in her eyes. “They are very much better, John. The lines are much clearer, and the color brighter.” “Still, that is only a step. It is of little use unless I can cut letters, and press them on vellum as I did these cards. I shall try thy name, Anna, and see if I cannot engrave it here on wood.” He took a small wooden tablet from the work-table in his shop, and marking certain lines upon it, cut away the wood so that it left a stamp of his wife’s name. Brushing ink over the raised letters he pressed the wood upon a sheet of paper, and then, lifting it carefully, showed her her own name printed upon the paper. “Wonderful!” she cried. “The letters have the very likeness of writing!” “Aye,” agreed Gutenberg, looking at the four letters, “it is not a failure. I think with patience and perseverance I could even impress a copy of our picture of St. Christopher. It must have been made from some manner of engraved block. See.” He took the rude print from the wall, and showed her on the back of it the marks of the stylus, or burnisher, by which it had been rubbed upon the wood. “Thou mayst be sure from this that these lines were not produced by a pen, as in ordinary writing,” said he. “Well,” said Anna, “it would surely be a pious act to multiply pictures of the holy St. Christopher.” Encouraged by his wife’s great interest, and spurred on by the passion for invention, Gutenberg now set himself seriously to study the problem of engraving. First of all he found it very difficult to find the right kind of wood. Some kinds were too soft and porous, others were liable to split easily. Finally he chose the wood of the apple-tree, which had a fine grain, was dense and compact, and firm enough to stand the process of engraving. Another difficulty was the lack of proper tools; but he worked at these until his box was supplied with a stock of knives, saws, chisels, and gravers of many different patterns. Then he started to draw the portrait of the saint.