Straightway it flashed upon the superintendent's mind that he had discussed the condition of the mine with Matthew Grote in hearing of this boy. He must, he felt convinced, have spoken of its large output, having no idea that this youth was an agent of his partner. If this were the case all his plans were upset. Gerald would of course communicate what he had heard to the old man. What was to be done? He must question Gerald and find out how much he knew, and whether he had written to Mr. Nixon. So when he next saw Gerald in the hotel he sat down beside him. "Where do you come from, young man? Haven't I seen you in Campville?" "I don't know. Have you been there recently?" "No, but one of my men has. Do you know old Tom Nixon?" "Yes, sir." "Did he send you here?" "Yes, sir." Nelson Hawk breathed hard. All his fears were realized. "Have you any communication for me? I wrote recently to Mr. Nixon, offering him a large sum for his interest in the mine. Do you think he will accept?" "I know he will not." "Why?" "Because it is worth much more than you offered." "Shall you advise him to refuse my offer?" "Yes, sir." "That is frank. I suppose you heard me say to Mr. Grote that the output had increased?" "Yes, sir." "And naturally you concluded that it is worth more than I offered. But there is another side to the question—expenses have increased, too. It is harder to work. Would you like to visit the mine and see for yourself?" "Yes, sir," said Gerald, promptly. Hawk's eyes lighted up with satisfaction. "Very well," he said; "we will go at once." They proceeded to the mine, half a mile away, and Hawk signaled for the elevator. It was a large cask, operated by a windlass. "Get in," he said. They did so, and began slowly to descend. The mine was about three hundred feet deep. Touching bottom, they left the tub, and Hawk began to show Gerald about, talking in a desultory way. At length they reached a side cavern, and Hawk led the way in. Then his manner changed. "Boy," he said, "are you authorized to sell Mr. Nixon's interest in the mine?" "Yes, sir." "I will give twenty thousand dollars." "I can't take it." "Be careful! You may come to harm if you don't?" "What do you mean?" demanded Gerald, startled. "I mean that I will keep you confined in this room until you agree to the bargain!" Gerald turned pale. He saw that he was in a trap. "I can't betray Mr. Nixon's interests." Hawk opened the door and went out, thrusting Gerald back. "I will come here to-morrow morning," he said. "By that time you may have come to your senses." "Let me out!" exclaimed Gerald, vehemently. "So I will, if you agree to my terms." In a moment the door was locked, and Gerald found himself immured in a cavern three hundred feet below the surface of the earth. [Illustration: HE SAW THAT HE WAS IN A TRAP] ------------------------------------------------------------------------