“Go ahead.”
“I shall put the spring-lock on the door, but it will not be used in the daytime. I shall fix it so that it will work at night.”
“Still I don’t see——”
“Wait. When we go to bed at night I shall leave the regular lock on; but I have a method by which I can cause the spring-lock to work if the door is opened and closed during the night. If Mr. Spook takes a fancy to come in here, the spring in the hinges of the door will cause it to close behind him, the spring-lock will fasten it, and Mr. Spook will be trapped.”
“But you think——”
“I think our spook is some fellow who has keys to fit the doors of a number of rooms. He can open the ordinary lock on this door, for he came here and carried off your penknife, which Chester Arlington afterward dropped.”
“Arlington is the spook.”
“Perhaps so. It seems that way. I did not tell you that, after the New Era game, while the crowd was pawing me over, another note was thrust into my hands, did I?”
“No.”
“Well, that was what happened. Of course, I couldn’t tell who put it there.”