"It is not uncommon for people to use it for things that are to stand weathering," said Henry, reluctantly. "I use it in my work in the garden."

"Is your custom in the matter generally known?"

"How can I tell?"

"Just for instance,--does Selby know?"

But Henry was guarding his expression now. He shook his head with rather an elaborate affectation of lack of interest. "I'm sure I couldn't say."

"Selby might carry a carpenter's pencil," mused Burton, "but he would be too shrewd to use it. Who would know your ways? Who comes frequently and familiarly to your house? Does Selby--again, just for instance,--have access to your house?"

"No," said Henry coldly. "He never comes there. That is, he never comes to our part of the house. He comes now and then to see Ben Bussey about work, but he goes to the back door."

"The back hall that runs by the door of the surgery?"

"Yes," said Henry. He turned away, as though to mark the end of the conversation, and Burton refrained from pressing him further.

Burton left the jail a good deal perplexed as to what he really did think of things by this time. He had jumped so enthusiastically to the conclusion the night before that Henry was innocent that he could not easily relinquish that hope, and yet certainly Henry had not cared at all to help him to establish it as a fact. He seemed more than unwilling to make any admission that would throw suspicion on Selby, and yet, if there were anything in expression, he hated Selby. Was it possible that just because he hated Selby he was so scrupulous not to implicate him? The idea struck Burton at first merely as a paradox, but the more he thought about it, the more he began to believe he had hit upon the truth. It was exactly the sort of Quixotism of which the doctor would have been guilty. Perhaps Henry was not so unlike his father as he appeared. If he knew or guessed, for instance, that Miss Hadley was wavering between himself and Selby, it was not difficult to understand that he would have considered it anything but "sporting" to involve his rival in the obloquy which had fallen upon himself. Well, if Miss Hadley were the key that would unlock Henry's heart,--or his lips,--he must try Miss Hadley again. Perhaps she could be moved to pity. He swerved out of his way to call again upon the banker's daughter.