We presently finished discussing the letter which was under consideration, and then opened the one which had been snatched from the lame gentleman. It contained nothing but a couple of perfectly blank sheets of note-paper! It was a chilly check to our hot eagerness and expectancy. We felt as blank as the paper, for a moment, and twice as foolish. But it was for a moment only; for, of course, we immediately afterward thought of “sympathetic ink.” We held the paper close to the fire and watched for the characters to come out, under the influence of the heat; but nothing appeared but some faint tracings, which we could make nothing of. We then called in the surgeon, and sent him off with orders to apply every test he was acquainted with till he got the right one, and report the contents of the letter to me the instant he brought them to the surface. This check was a confounded annoyance, and we naturally chafed under the delay; for we had fully expected to get out of that letter some of the most important secrets of the plot. Now appeared Sergeant Rayburn, and drew from his pocket a piece of twine string about a foot long, with three knots tied in it, and held it up. “I got it out of a gun on the water-front,” said he. “I took the tompions out of all the guns and examined close; this string was the only thing that was in any gun.” So this bit of string was Wicklow’s “sign” to signify that the “Master’s” commands had not miscarried. I ordered that every sentinel who had served near that gun during the past twenty-four hours be put in confinement at once and separately, and not allowed to communicate with any one without my privity and consent. A telegram now came from the Secretary of War. It read as follows:— “Suspend _habeas corpus_. Put town under martial law. Make necessary arrests. Act with vigor and promptness. Keep the Department informed.” We were now in shape to go to work. I sent out and had the lame gentleman quietly arrested and as quietly brought into the fort; I placed him under guard, and forbade speech to him or from him. He was inclined to bluster at first, but he soon dropped that. Next came word that Wicklow had been seen to give something to a couple of our new recruits; and that, as soon as his back was turned, these had been seized and confined. Upon each was found a small bit of paper, bearing these words and signs in pencil:— +-------------------------+ | EAGLE’S THIRD FLIGHT. | | REMEMBER XXXX. | | 166. | +-------------------------+