Théophraste seated himself on the wicker chair in the small room which served as a workshop. This room was lighted by a large window reaching from floor to ceiling. “Ambrose, you are an expert. No one can approach you in the knowledge of papers, eh?” “That is not quite true,” said Ambrose, “but I can judge a good paper.” “You understand all kinds?” “All kinds.” “If some one showed you a piece of paper, could you tell the age of it?” “Yes,” said Ambrose, “I could. I have published a treatise on the water-marks of papers used in France in the seventeenth and eighteenth centuries. That study was accepted by the Academy.” “I know, and I have great respect for your knowledge.” “Well, the thing is simple. The oldest paper showed a plain, glossy surface, but soon there appeared wide lines crossed at intervals by perpendicular lines, both giving the impression of a metal trellis over which the paste had been spread. From the fourteenth century they used these as a maker’s mark, and in the end they designed figures in brass wire, initials, words, emblems of all sorts —these are the water-marks. Every sheet of water-marked paper tells its tale, and the year of its make can be detected, but the difficulty is to decipher it. This necessitates a little practice.” Théophraste opened his portfolio and took out the paper. “Can you tell me the exact date of this?” Ambrose put on his eyeglass and took the paper to the daylight. “There is the date,” he said, “172--, the last figure is rubbed out. It must be of the eighteenth century.” “Oh,” said Théophraste, “I saw that date quite well, but do you really think that the paper is-of that century? Does not the date lie? That is what I want to know.” Ambrose showed him the center of the paper. “See?” Théophraste said nothing. Then Ambrose lit a small lamp and held the paper up before it. In illuminating the document one could detect in the thickness of the paper the design of a crown. “Théophraste,” said Ambrose excitedly, “that paper is exceedingly rare. That mark is almost unknown, for a very little paper was made with that sign, which is called the Crown of Thorns. That paper, my dear Théophraste, was made in 1721.” “You are sure?” “Yes, but tell me,” cried Ambrose, who could not conceal his surprise, “how is it that this document, dated 1721, could be by all visible marks in your handwriting?” Théophraste said nothing, but getting up and putting the document back into the portfolio, he hastened out of the house.