this late visit was indeed
intended for us. With some curiosity as to what could have sent a
brother medico to us at such an hour, I followed Holmes into our
sanctum.

A pale, taper-faced man with sandy whiskers rose up from a chair by the
fire as we entered. His age may not have been more than three or four
and thirty, but his haggard expression and unhealthy hue told of a life
which has sapped his strength and robbed him of his youth. His manner
was nervous and shy, like that of a sensitive gentleman, and the thin
white hand which he laid on the mantelpiece as he rose was that of an
artist rather than of a surgeon. His dress was quiet and sombre--a black
frock-coat, dark trousers, and a touch of color about his necktie.

"Good-evening, doctor," said Holmes, cheerily. "I am glad to see that
you have only been waiting a very few minutes."

"You spoke to my coachman, then?"

"No, it was the candle on the side-table that told me. Pray resume your
seat and let me know how I can serve you."

"My name is Doctor Percy Trevelyan," said our visitor, "and I live at
403 Brook Street."

"Are you not the author of a monograph upon obscure nervous lesions?" I
asked.

His pale cheeks flushed with pleasure at hearing that his work was known
to me.

"I so seldom hear of the work that I thought it was quite dead," said
he. "My publishers gave me a most discouraging account of its sale. You
are yourself, I presume, a medical man?"

"A retired army surgeon."

"My own hobby has always been nervous disease. I should wish to make it
an absolute specialty, but, of course, a man must take what he can get
at first. This, however, is beside the question, Mr. Sherlock Holmes,
and I quite appreciate how valuable your time is. The fact is that a
very singular train of events has occurred recently at my house in Brook
Street, and to-night they came to such a head that I felt it was quite
impossible for me to wait another hour before asking for your advice and
assistance."

Sherlock Holmes sat down and lit his pipe. "You are very welcome
to both," said he. "Pray let me have a detailed account of what the
circumstances are which have disturbed you."

"One or two of them are so trivial," said Dr. Trevelyan, "that really
I am almost ashamed to mention them. But the matter is so inexplicable,
and the recent turn which it has taken is so elaborate, that I shall
lay it all before you, and you shall judge what is essential and what is
not.