He had risen and paced the room as he spoke. Now he halted in the recess of the window. There was such a ring of conviction in his voice that I glanced up in surprise.

“My dear fellow, how can you possibly be so sure of that?”

“For the very simple reason that I see the dog himself on our very door-step, and there is the ring of its owner. Don’t move, I beg you, Watson. He is a professional brother of yours, and your presence may be of assistance to me. Now is the dramatic moment of fate, Watson, when you hear a step upon the stair which is walking into your life, and you know not whether for good or ill. What does Dr. James Mortimer, the man of science, ask of Sherlock Holmes, the specialist in crime? Come in!”

The appearance of our visitor was a surprise to me, since I had expected a typical country practitioner. He was a very tall, thin man, with a long nose like a beak, which jutted out between two keen, grey eyes, set closely together and sparkling brightly from behind a pair of gold-rimmed glasses. He was clad in a professional but rather slovenly fashion, for his frock-coat was dingy and his trousers frayed. Though young, his long back was already bowed, and he walked with a forward thrust of his head and a general air of peering benevolence. As he entered his eyes fell upon the stick in Holmes’s hand, and he ran towards it with an exclamation of joy. “I am so very glad,” said he. “I was not sure whether I had left it here or in the Shipping Office. I would not lose that stick for the world.”

“A presentation, I see,” said Holmes.

“Yes, sir.”

“From Charing Cross Hospital?”

“From one or two friends there on the occasion of my marriage.”

“Dear, dear, that’s bad!” said Holmes, shaking his head.

Dr. Mortimer blinked through his glasses in mild astonishment. “Why was it bad?”

“Only that you have disarranged our little deductions. Your marriage, you say?”

“Yes, sir. I married, and so left the hospital, and with it all hopes of a consulting practice. It was necessary to make a home of my own.”

“Come, come, we are not so far wrong, after all,” said Holmes. “And now, Dr. James Mortimer—”

“Mister, sir, Mister—a humble M.R.C.S.”

“And a man of precise mind, evidently.”

“A dabbler in science, Mr. Holmes, a picker up of shells on the shores of the great unknown ocean. I presume that it is Mr. Sherlock Holmes whom I am addressing and not—”

“No, this is my friend Dr. Watson.”