Ben turned his head at that and looked at his questioner. The look of triumph that flashed into his eyes was as plain as any words could have been, but he did not answer otherwise.
"Take him to the station," Watson said to his men.
But Burton interposed. He had been watching Ben, and he saw that if they were to get anything from him in the way of an admission, he must be goaded into speech before he had time to fully realize the advantages of standing persistently mute.
"No hurry about that," he said, with a slight sign to the chief. "I want to tell you something about how I got on this trail, and Ben may as well hear it."
"There are important matters waiting," Watson reminded him, in a significant aside.
"Nothing more important than this--now," said Burton. Watson hesitated, but drew back, leaving Ben, with a policeman on either side of him, where the light fell on his somber face.
"I was first positively convinced that Henry Underwood was not the man on the night of the Hadley assault," Burton began, with deliberation. "That knotting of the rope was too neat for a man with a forefinger as stiff as a wooden peg. You made a mistake that time, Ben. Didn't your mother tell you that Henry had cut his finger?"
But Ben refused to be drawn. He lifted his upper lip over his closed teeth, but gave no other sign of attending.
"Of course it was clear from the first that the person who was making the trouble had easy access to the Underwood house and very up-to-date information about everything that went on in the house. At first I, too, thought it must be Henry. Then, when I satisfied myself that it wasn't, I began to keep a watch on Selby."
"Poor old Selby," said Ralston, with sudden recollection.
"Poor old Henry," said Burton sternly. "He has been goaded past endurance. Selby's slate was by no means clear, though I acquit him of many of my suspicions. But I am telling you now why I suspected him. He hated Henry and was jealous of him. He was a party to the discovery of Henry's knife near the Sprigg house, and I thought I had reason to believe he had himself dropped it there. He had access to the Red House through his business relations with Ben, and Mrs. Bussey was an eavesdropper and spy who could easily have given him the inside information required. Finally he had in his possession a number of Indian baskets and was known to have been much among the Indians as a boy. I was certain that the strong and supple fingers that had twisted the lilac bushes into a net to hold the Sprigg baby and that had knotted the cords into a snare about Mr. Hadley had learned the trick of Indian weaving when they were young."