Gregson looked quite crest-fallen.

“I had no idea that you noticed that,” he said. “Have you been there?”

“No.”

“Ha!” cried Gregson, in a relieved voice; “you should never neglect a chance, however small it may seem.”

“To a great mind, nothing is little,” remarked Holmes, sententiously.

“Well, I went to Underwood, and asked him if he had sold a hat of that size and description. He looked over his books, and came on it at once. He had sent the hat to a Mr. Drebber, residing at Charpentier’s Boarding Establishment, Torquay Terrace. Thus I got at his address.”

“Smart—very smart!” murmured Sherlock Holmes.

“I next called upon Madame Charpentier,” continued the detective. “I found her very pale and distressed. Her daughter was in the room, too—an uncommonly fine girl she is, too; she was looking red about the eyes and her lips trembled as I spoke to her. That didn’t escape my notice. I began to smell a rat. You know the feeling, Mr. Sherlock Holmes, when you come upon the right scent—a kind of thrill in your nerves. ‘Have you heard of the mysterious death of your late boarder Mr. Enoch J. Drebber, of Cleveland?’ I asked.

“The mother nodded. She didn’t seem able to get out a word. The daughter burst into tears. I felt more than ever that these people knew something of the matter.

“‘At what o’clock did Mr. Drebber leave your house for the train?’ I asked.

“‘At eight o’clock,’ she said, gulping in her throat to keep down her agitation. ‘His secretary, Mr. Stangerson, said that there were two trains—one at 9.15 and one at 11. He was to catch the first.’

“‘And was that the last which you saw of him?’

“A terrible change came over the woman’s face as I asked the question. Her features turned perfectly livid. It was some seconds before she could get out the single word ‘Yes’—and when it did come it was in a husky unnatural tone.

“There was silence for a moment, and then the daughter spoke in a calm clear voice.

“‘No good can ever come of falsehood, mother,’ she said. ‘Let us be frank with this gentleman. We did see Mr. Drebber again.’

“‘God forgive you!’ cried Madame Charpentier, throwing up her hands and sinking back in her chair. ‘You have murdered your brother.’

“‘Arthur would rather that we spoke the truth,’ the girl answered firmly.

“‘You had best tell me all about it now,’ I said. ‘Half-confidences are worse than none. Besides, you do not know how much we know of it.’