“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?’