that moment my son Arthur came into the room. What happened then I do not know. I heard oaths and the confused sounds of a scuffle. I was too terrified to raise my head. When I did look up I saw Arthur standing in the doorway laughing, with a stick in his hand. “I don’t think that fine fellow will trouble us again,” he said. “I will just go after him and see what he does with himself.” With those words he took his hat and started off down the street. The next morning we heard of Mr. Drebber’s mysterious death.’

“This statement came from Mrs. Charpentier’s lips with many gasps and pauses. At times she spoke so low that I could hardly catch the words. I made shorthand notes of all that she said, however, so that there should be no possibility of a mistake.”

“It’s quite exciting,” said Sherlock Holmes, with a yawn. “What happened next?”

“When Mrs. Charpentier paused,” the detective continued, “I saw that the whole case hung upon one point. Fixing her with my eye in a way which I always found effective with women, I asked her at what hour her son returned.

“ ‘I do not know,’ she answered.

“ ‘Not know?’

“ ‘No; he has a latchkey, and he let himself in.’

“ ‘After you went to bed?’

“ ‘Yes.’

“ ‘When did you go to bed?’

“ ‘About eleven.’

“ ‘So your son was gone at least two hours?’

“ ‘Yes.’

“ ‘Possibly four or five?’

“ ‘Yes.’

“ ‘What was he doing during that time?’

“ ‘I do not know,’ she answered, turning white to her very lips.

“Of course after that there was nothing more to be done. I found out where Lieutenant Charpentier was, took two officers with me, and arrested him. When I touched him on the shoulder and warned him to come quietly with us, he answered us as bold as brass, ‘I suppose you are arresting me for being concerned in the death of that scoundrel Drebber,’ he said. We had said nothing to him about it, so that his alluding to it had a most suspicious aspect.”

“Very,” said Holmes.

“He still carried the heavy stick which the mother described him as having with him when he followed Drebber. It was a stout oak cudgel.”

“What is your theory, then?”

“Well, my theory is that he followed Drebber as far as the Brixton Road. When there, a fresh altercation arose between them, in the course of which Drebber received a blow from the stick, in the pit of the