“You see,” said Ed, “this gas puts out fire, and it puts out life in the same way. It smothers both. It absolutely excludes oxygen, and neither animal life nor fire can exist without oxygen. Do I make the thing clear?” “Perfectly,” said all the boys. “Then that’s why we choked so when we went down the ladder?” said Phil. “Certainly. Your air was as completely cut off as if you had dived into water. That’s why I cautioned you to hold your breath just as if you had been diving into the river.” CHAPTER XVI “TALKING BUSINESS” Naturally the boys were too much excited over their capture to talk of anything else, and for a time they did not even think or talk of the most important phase of that. They discussed the shooting, which all of them saw to be reason enough for the arrest, but it was not until well on into the night that any of them thought to ask Phil about the results of his search of Jim’s satchel. Meantime they had carried the pinioned man below and securely bound him to his bunk. Then they had cooked and eaten their supper, talking all the time, each playfully describing his own consternation at every step of the late proceeding. Finally Will Moreraud said:-- “By the way, what does it all mean?” “Yes,” joined in Irv Strong, “it at last begins to dawn upon my hitherto excited consciousness, that we have not yet heard the results of Phil’s explorations among Jim’s effects. Tell us all about it, Phil.” They were sitting in the cabin, or half way in it. That is to say, Phil was sitting in the mouth of the scuttle above, watching the river and the course of the flatboat; Irv sat just below him on the steps, and the other boys were gathered around the little table at the foot of the ladder. “One of you come up here, then,” said Phil, “and keep the lookout while I tell you about it. I thought you’d ask after you got through relating your personal experiences.” Ed volunteered to take the place at the top of the stairs, although his frail nerves were now quivering after the strain he had been through. Phil seized the carpet-bag which he had instinctively kept under his hand all the time, and descended the ladder. There he opened it and spread its contents on the table. “These are what I have found,” he said, suppressing his excitement. “This big bundle of government bonds,” laying it on the table; “this big bundle of railroad and other securities,” laying that down in its turn; “this great wad of greenbacks, and, best of all, _these_!” As he finished, he held up a bundle of letters. “What are they? Why are they the best part of all?” queried the boys in a breath. “They are letters from Jim Hughes’s fellow criminals. I called them ‘best of all’ because they will enable the authorities to catch and convict the whole gang!” The exultation of the crew was great. “We shall have rendered a great service to the public, shan’t we?” asked Constant.