Having sent one of his men back to order up the horses, the lieutenant formed his captives in line, threw a guard around them and marched them into the fort. Halting them on the parade, he went in to report to the colonel, and when he came out again he put every one of them into the guard-house; after which Bob and his companions went to the quarters and tumbled into their bunks.
Great was the astonishment among the soldiers the next morning when it became known that the expedition, which they supposed had gone out in search of the hostiles, had returned to the fort and captured thirty armed men, and that the work had been done so quietly that the sentry at the gate never knew anything about it until it was all over. Of course they were quite at a loss to determine who it was that told the colonel about it; and the general impression seemed to be that if there were a traitor among the deserters, he had allowed himself to be captured with the others in order to avoid suspicion.
Among the non-commissioned officers who had attempted to desert was one of the corporals belonging to Bob's troop, and the next morning Bob was ordered to take his place and do duty as corporal of the guard. He saw the prisoners served with breakfast, and the numerous orders he had to give opened the eyes of one of them, who began to think he had made a discovery. And so he had, but he could not prove it.
"I'll tell you what's a fact, boys," said Bristow as he walked to a remote corner of his prison with a cup of coffee in one hand and some cracker and bacon in the other: "I know whom we have to thank for our arrest."
"Who is it?" asked a dozen voices at once.
"I'd like to send him my compliments in the shape of a bullet from my carbine," said the corporal whose place Bob was then filling. "Tell us who he is, so that we can improve the first chance to get even with him."
"There he is," said Bristow, shaking his piece of cracker at Bob. "He has been trying to get on the blind side of the officers for a long time, as you all know, and he has accomplished his object at last by going back on his comrades."
The prisoners looked at Bob as if they expected him to deny the accusation; but, to the disappointment of some of them who really liked him, he had nothing to say.
"Why don't you speak up and declare that it isn't so?" demanded the corporal.
"Because he dare not," exclaimed Bristow. "He couldn't without telling a lie, and, as he is a good little boy, he wouldn't do that for the world."