"Here's a nice old man, living happily, and gradually getting away from his delusion. Here's an agent of the devil trying to drive this old man back to his delusion, and make a lunatic of him, for that's what the doctor says will certainly happen. "I say it's too bad, not to mention the jewels at all. Now, what are we going to do about it?" "Catch the rascal," said Nick, promptly, "and catch him mighty quick." "Well, I hope you'll succeed. I tell you, Mr. Carter, I feel toward Colonel Richmond all the affection that I would give my father, if he were alive, and I can't bear to see him driven out of his wits in this infernal way." "Have no fear," said Nick; "we'll save him. This trickery with the servants may give us a chance to catch our man." They returned to the parlor in the new part of the house. Colonel Richmond was not there. "Where is he?" asked Horace, anxiously, of Mrs. Pond. "He has gone to his room. He said that the excitement of this affair had worn him out completely." Horace looked relieved. Nick said that he, too, would go to his room. He went, but he did not remain long in it. He had a fancy for a quiet stroll around the house on the outside. It would be interesting to know whether anybody entered or left it during the night. One of the secret passages of the old house communicated with a sort of tunnel, which had its outer extremity in an old well about twenty yards away. This tunnel had caved in long before, but had been restored by Colonel Richmond, who wished to preserve all the old-time peculiarities of the place. The inner end of it had been closed by a strong door, so as to prevent anybody who might have the secret from entering in that way, but Nick was strongly of the opinion that it would not keep out the persons who were "haunting" the house in case they desired to come in. If anybody was going in and out secretly this seemed to be the readiest way, so Nick had resolved to watch the well that night. A little house with sides of lattice-work had been built over it, and vines covered it. Nick stealthily crept into its shadow, and prepared for his vigil. But it was not destined to be a long one. He had not been there ten minutes before he saw a figure hastening along one of the numerous paths which wound through the grounds. This person evidently wished to avoid observation, and that was enough for Nick. He immediately started in pursuit. He trailed his man to the edge of the colonel's grounds. During this pursuit the man kept in the shadow of some trees, and Nick had no opportunity to see him clearly. But as the man stepped out into the highway, a ray of moonlight fell upon him, and Nick recognized him in an instant. It was Colonel Richmond. Why this man should be leaving his own house by stealth and under the cover of darkness was an interesting problem. Nick resolved to know all about it before the night was much older. So he trailed along. The colonel walked up the highway with rapid strides.