A knock came at the door. It was Professor Durand. The old man had doffed his dignity, and was in slippers and a dressing-gown. He bowed profoundly to Margot, then he said to Hugh with a benevolent smile:
“I saw a light and thought you might have returned. I am lonely. I wonder if you would care to come to my den and smoke a pipe.”
Hugh followed the old man. The room surprised him. There was a steel safe in one corner, a large cabinet, a broad table covered with papers on which were algebraic formulæ and geometrical figures.
“My workshop,” said the professor. “You saw me to-day? Eh, what!”
“Yes, I congratulate you. You made a wonderful beginning.”
“No, I’m not satisfied. My timing was out. To-morrow I’ll do better. I’ll only play once, but I’ll hit it.”
The professor spoke with such conviction that Hugh was impressed.
“Extraordinary! A marvellous system. A discovery.”
“No, not a discovery, an invention. Just as logarithms was an invention. But remember, it took me twenty years to perfect it with all the resources of the higher mathematics at my command. Twenty years! Come, take that easy chair and light up. I’m going to give you a liqueur, some very old Chartreuse; and we’ll talk.”
The professor, however, did most of the talking. “Look,” said he, “at that stack of green volumes. You have there the records of table number two for the past thirteen years. I know that table like a living thing, and yet I never saw it until to-day.”