He jumped up suddenly and set the fires leaping in two braziers. He melted a gum in one of them and heated some liquid in the other. At length at the end of fifteen minutes he covered the fires and took out the substances. With a small brush he smeared the mixture of the two over his long student gown that hung against the wall. Then he took the mask which he used when making experiments with certain poisonous gases, and covered this with the same drug he had compounded in the braziers—the gum causing it to cling to the surface of the mask. “I have but to sprinkle this with aqua phosphorata,” he said to himself, “and the heavens will not be more brilliant than I.” He sat back in his chair to wait, and with closed eyes tried to reason it all out. “What can be the meaning of this?” he thought. “The stranger with Stas stopped on the landing of Pan Andrew’s lodging. What mystery can have attached itself to this family? Why should the name be changed? Who would seek revenge upon a man and a woman and a boy? Elzbietka has found a mother, and I good friends. They have no treasure with them, no money of any kind, for even on that first day Pan Andrew was obliged to sell his cart and horses for the means of living.” He was becoming drowsy, for he had worked much of late, and had had but little sleep, and he was on the point of succumbing to his weariness when he heard the watchman at the Church of our Lady Mary strike twice upon the bell and then begin to play the Heynal. The fourth Heynal was scarcely finished when he heard a motion in the court below. It was Stas creeping along the wall in order to open the door. Throwing back his door noiselessly the alchemist lay flat on the floor and leaned out over the threshold. The door below creaked a little as it opened. Some one came in. The alchemist listened. “One—two—three—more! By the lightning, there must be a dozen of them, if footsteps tell no lies. I did wrong not to notify the watch. If I shout now, he may come, but there are enough to silence both him and me. No, I have made my beer and I must drink it.” Next the stairs began to creak, and almost instantly the hoarse barking of a dog cut through the air. “Silence that dog,” he heard some one whisper from the steps. Footsteps were heard again in the court as if someone had gone back to combat the animal. At this same moment the door leading into the court was slammed shut, and there was a rattle of the chain that fastened it on the inside. “A precious jewel, that Stas,” thought the alchemist. “He shall pay for this to-morrow.” A cry of pain rang out suddenly from below. It was the cry not of a dog, but of a man. “Ha,” thought Pan Kreutz, “Wolf finished that one.” There was a sound of a man running across the court. “I can’t get near him without injury,” he whispered loudly to the leader of the party. “He sank his teeth in my leg, and I am faint for pain.” “Three of you attack him at once,” directed the leader.