Rabig seemed to be trying to think up a reply, but nothing came to him and he simply stood still and glowered at them. He appeared to be speculating. What significance was there in these apparently careless questions? Why should they be asked at all? How much did these cordially hated acquaintances of his really know? "I hear that one of the Germans was killed close to our lines last night," said Billy, shifting the attack. "Right inside our lines," corrected Tom. "And here's the fellow who shot him," pointing to Frank. "Frank has nerve," drawled Billy. Rabig shot a glare of hate that was not lost by the onlookers, who kept their eyes steadily on his face. "He nearly got another one, too," observed Bart. "And the funny thing about it was that he thought he knew the fellow's voice." This was coming too near for Rabig to pretend that he did not know what they were driving at. He turned upon them in desperation. "Look here," he snarled viciously. "What do you fellows mean? If you mean that I'm mixed up in this thing you lie. Now don't you speak to me again or I'll make you sorry for it." Without waiting for a reply he hurried off, and the four Camport chums looked after him with speculation in their eyes until he was lost to view at a turn of the trench. "He's guilty all right," declared Tom with conviction. "If ever guilt looked out of a man's eyes they looked out of his," agreed Bart. "It seems so," admitted Frank with reluctance, "and yet he was in his bunk when I went through last night." "How do you know it was Rabig?" Tom retorted. "Are you such a cute detective that you can tell one man's snore from another?" "Who else could it have been?" asked Frank. "If it was some one else, that some one else must have been in cahoots with Rabig and agreed to make him seem to be in his bunk. I'd hate to think that there was more than one traitor in the regiment. "One's more than enough," agreed Bart. "What do you think we ought to do about it?" asked Billy. "I don't know," replied Frank, with a worried look on his face. "It would be a terrible thing to accuse a man wrongfully of such a thing as treason. Rabig would simply deny it and put it up to us to prove it. Then, too, every one knows that there's no love lost between us and Nick, and they might think we were too ready to believe evil of him without real proof." "On the other hand," replied Tom, "if we let him go on, we may wake up some time to find that Rabig has done the regiment more harm than a German battery could do." "We'll simply have to keep our eyes peeled," was Billy's solution of the problem, "and watch that fellow like hawks. But if he makes one more bad break I don't think we ought to keep silent any longer. Let's hope that next time, if there is any next time, we'll have the goods on him so that there can't be any denying it."