As soon as I was left alone, I returned to the bedside and once more looked down at the impassive figure. And as I looked, my suspicions revived. It was very like morphine poisoning; and, if it was morphine, it was no common, medicinal dose that had been given. I opened my bag and took out my hypodermic case from which I extracted a little tube of atropine tabloids. Shaking out into my hand a couple of the tiny discs, I drew down the patient’s underlip and slipped the little tablets under his tongue. Then I quickly replaced the tube and dropped the case into my bag; and I had hardly done so when the door opened softly and the housekeeper entered the room.

“How do you find Mr. Graves?” she asked in what I thought a very unnecessarily low tone, considering the patient’s lethargic state.

“He seems to be very ill,” I answered.

“So!” she rejoined, and added: “I am sorry to hear that. We have been anxious about him.”