I began to understand what my friend meant when he said that his brother possessed even keener faculties that he did himself. He glanced across at me and smiled. Mycroft took snuff from a tortoiseshell box, and brushed away the wandering grains from his coat front with a large, red silk handkerchief.

“By the way, Sherlock,” said he, “I have had something quite after your own heart⁠—a most singular problem⁠—submitted to my judgment. I really had not the energy to follow it up save in a very incomplete fashion, but it gave me a basis for some pleasing speculation. If you would care to hear the facts⁠—”

“My dear Mycroft, I should be delighted.”

The brother scribbled a note upon a leaf of his pocketbook, and, ringing the bell, he handed it to the waiter.