Steve found himself a little weak from his experiences, and it was decided that he should remain in the mine for the rest of the night, or until the cage machinery had been repaired so he could ride up. The surgeon sat nodding in the pump-man's chair, and the men who had assisted in the rescue returned to their duties in other parts of the mine. Mr. Penton had been in communication with the surface by telephone. He learned that all was being done that could be done to repair the hoisting apparatus in the shortest possible time, so there was no necessity for him to climb the rest of the way up. "I think I'll stay down here with you boys for the rest of the night," he said. "Everything is quiet. I see the surgeon has put the engineer out of house and home, so I think I shall lie down on the work-bench and get a little sleep." "Yes, it is quiet enough," began Steve, when suddenly there came a dull, muffled report. The ground beneath their feet trembled perceptibly, then silence reigned. Mr. Penton sprang from the bench where he was just composing himself for a sleep. "Did you hear that!" "Yes, sir; we heard it," answered Rush. "What was it?" questioned Bob, his head inclined in a listening attitude. "It sounded like an explosion," said Steve. "It _was_ an explosion. That was dynamite, boys. Something is going on here. There should be no blasting in the mines to-night." Mr. Penton ran to the telephone to find out what the explosion meant. "It looks as though our work were cut out for us, Steve," said Jarvis in a low tone. "I am beginning to think so myself," answered Steve, after listening intently for a moment. CHAPTER XXIV CONCLUSION "What was it, Mr. Penton?" called Steve, as he saw the superintendent approaching. "I shall have to leave you," returned the superintendent. "Jarvis, if Rush does not need you, you may come with me." "Is there any trouble, sir?" questioned Steve. "Yes; there is trouble. Someone has dropped a charge of dynamite down the cage shaft. They tell me the cage is wrecked. Of course that doesn't amount to much, if there is no further damage, but there is no telling where this business is going to end. I must get up to the surface, and at once." "Then I am going with you," announced Steve with emphasis. "I am perfectly able. There is nothing the matter with me except inactivity. I am anxious to be doing something. But, Mr. Penton, that charge of dynamite surely was not dropped in from the surface, was it?" "No; that would not be possible." "That means that someone in the mine has dropped it from one of the levels." "Yes, yes." "Then I would suggest telephoning to the top of the shaft to have the ladder hole leading to the open watched, and no one to be allowed to leave the mine unless able to give a good account of himself." "Your idea is an excellent one. I will give the order at once."