"A clue, certainly," said Godfrey; "but scarcely to the murderer."

The doctor looked at it again for a moment, and then nodded. "I'd better put it back where I found it, I guess," he said, and dropped it beside the chair.

And then, suddenly, I remembered Swain. I turned to find him still drooping forward in his chair, apparently half-asleep.

"Doctor," I said, "there is someone else here who is suffering from shock," and I motioned toward the limp figure. "Or perhaps it's something worse than that."

The doctor stepped quickly to the chair and looked down at its occupant. Then he put his hand under Swain's chin, raised his head and gazed intently into his eyes. Swain returned the gaze, but plainly in only a half-conscious way.

"It looks like a case of concussion," said the doctor, after a moment. "The left pupil is enlarged," and he ran his hand rapidly over the right side of Swain's head. "I thought so," he added. "There's a considerable swelling. We must get him to bed." Then he noticed the bandaged wrist. "What's the matter here?" he asked, touching it with his finger.

"He cut himself on a piece of glass," Godfrey explained. "You'd better take him over to my place, where he can be quiet."

"I've got my car outside," said the doctor, and together he and I raised Swain from the chair and led him to it.

He went docilely and without objection, and ten minutes later, was safely in bed, already dozing off under the influence of the opiate the doctor had given him. "He'll be all right in the morning," the latter assured me. "But he must have got quite a blow over the head."

"I don't know what happened to him," I answered. "You'll come back with me, won't you?"