The strain of events was telling on us all. Quintus Oakes showed his deep concern by a tendency to leave us and remain alone. As Elliott and I were talking, he looked at the rolling hills beyond the pond and exclaimed: "Look! Can I be mistaken, Mr. Stone? Look in the direction of Mona--away off on the plateau--is not that a horse?" I followed his pointing and discovered in the moonlight the figure of a horse advancing rapidly over the blue-green fields, along the path that led to the bridge. Oakes advanced to the window and gazed intently, shading his eyes with his hands. On the crest of the hill that dipped to the pond the horse soon stood out clearly against the dark blue of the sky. We could see a figure which had lain low on his neck rise and sit straight in the saddle, then flash a light. From near the road, on our side of the pond, came an answering light; a man stood there and exchanged signals with the horseman. The rider was moving his arms rapidly, and with them the light. The other was answering in a similar manner. Oakes remained quiet, and we all gathered at the window about him. "What is it?" I asked. He turned and said to me: "Here, write as I read." I took an envelope and pencil from my pocket and wrote as Oakes deciphered the signals. "A message from Mona," he cried. "Quick!" Then he read the letters as they appeared: "Discovered. Skinner has extra out. Pronounces me false; says Hallen has tricked the town. Beware of Skinner. Tell Hallen to look out. Am off for New York." Then came a long wave over the head, and the horseman dashed back toward Lorona. We detected another horseman at a little distance, who joined him; they rapidly disappeared together. "Excellent!" exclaimed Oakes. "He has done his duty well." We saw the man on this side run post haste for the Mansion. As he rushed up the steps, Oakes met him. "All right, boy! I saw the signals myself." Then to us he said: "Quintus Oakes the false is discovered. That was he; he came to warn us." "Then Skinner has caught on, confound him," said Dowd, and we all silently assented. Oakes paced the room slowly. "Boys, we have been unexpectedly checked. The enemy has a strong hand: there is trouble ahead." "Yes, there is that," retorted the vigorous Hallen. "I must get away to headquarters, gentlemen!" "Correct!" answered Oakes; "and we will go with you, Chief. If trouble is coming, we will be useless here." With one accord we prepared to depart for Mona immediately. The carriage was brought to the door and saddle-horses also. Then we waited anxiously for the return of Martin's party. We were not long delayed. A commotion in the hall was heard, and in stepped Joe and Martin, followed by the men. Oakes's assistant advanced and laid a red handkerchief, dotted with white spots, upon the table. It was wet and heavy, and knotted by its four corners so as to form a pouch.