P.C.' on the flap.
There was half an ounce of strong ship's tobacco in it."

"Excellent! What more?"

Stanley Hopkins drew from his pocket a drab-covered note-book. The
outside was rough and worn, the leaves discoloured. On the first page
were written the initials "J.H.N." and the date "1883." Holmes laid
it on the table and examined it in his minute way, while Hopkins and I
gazed over each shoulder. On the second page were the printed letters
"C.P.R.," and then came several sheets of numbers. Another heading was
Argentine, another Costa Rica, and another San Paulo, each with pages of
signs and figures after it.

"What do you make of these?" asked Holmes.

"They appear to be lists of Stock Exchange securities. I thought that
'J.H.N.' were the initials of a broker, and that 'C.P.R.' may have been
his client."

"Try Canadian Pacific Railway," said Holmes.

Stanley Hopkins swore between his teeth and struck his thigh with his
clenched hand.

"What a fool I have been!" he cried. "Of course, it is as you say. Then
'J.H.N.' are the only initials we have to solve. I have already examined
the old Stock Exchange lists, and I can find no one in 1883 either in
the House or among the outside brokers whose initials correspond with
these. Yet I feel that the clue is the most important one that I hold.
You will admit, Mr. Holmes, that there is a possibility that these
initials are those of the second person who was present--in other words,
of the murderer. I would also urge that the introduction into the case
of a document relating to large masses of valuable securities gives us
for the first time some indication of a motive for the crime."

Sherlock Holmes's face showed that he was thoroughly taken aback by this
new development.

"I must admit both your points," said he. "I confess that this
note-book, which did not appear at the inquest, modifies any views which
I may have formed. I had come to a theory of the crime in which I
can find no place for this. Have you endeavoured to trace any of the
securities here mentioned?"

"Inquiries are now being made at the offices, but I fear that the
complete register of the stockholders of these South American concerns
is in South America, and that some weeks must elapse before we can trace
the shares."

Holmes had been examining the cover of the note-book with his magnifying
lens.

"Surely there is some discolouration here," said he.

"Yes, sir, it is a blood-stain. I told yo