gone hard with me. But I read suspicion in his eyes. Please

 burn the cipher message, which can now be of no use to you.

                                              FRED PORLOCK."

Holmes sat for some little time twisting this letter between his
fingers, and frowning, as he stared into the fire.

"After all," he said at last, "there may be nothing in it. It
may be only his guilty conscience. Knowing himself to be a
traitor, he may have read the accusation in the other's eyes."

"The other being, I presume, Professor Moriarty."

"No less! When any of that party talk about 'He' you know whom
they mean. There is one predominant 'He' for all of them."

"But what can he do?"

"Hum! That's a large question. When you have one of the
first brains of Europe up against you, and all the powers of
darkness at his back, there are infinite possibilities. Anyhow,
Friend Porlock is evidently scared out of his senses -- kindly
compare the writing in the note to that upon its envelope; which
was done, he tells us, before this ill-omened visit. The one is
clear and firm. The other hardly legible."

"Why did he write at all? Why did he not simply drop it?"

"Because he feared I would make some inquiry after him in
that case, and possibly bring trouble on him."

"No doubt," said I. "Of course." I had picked up the original
cipher message and was bending my brows over it. "It's pretty
maddening to think that an important secret may lie here on this
slip of paper, and that it is beyond human power to penetrate it."

Sherlock Holmes had pushed away his untasted breakfast and
lit the unsavoury pipe which was the companion of his deepest
meditations. "I wonder!" said he, leaning back and staring at
the ceiling. "Perhaps there are points which have escaped your
Machiavellian intellect. Let us consider the problem in the light
of pure reason. This man's reference is to a book. That is our
point of departure."

"A somewhat vague one."

"Let us see then if we can narrow it down. As I focus my
mind upon it, it seems rather less impenetrable. What indications
have we as to this book?"

"None."

"Well, well, it is surely not quite so bad as that. The cipher
message begins with a large 534, does it not? We may take it as
a working hypothesis that 534 is the particular page to which the
cipher refers. So our book has already become a large book
which is surely something gained. What other indications have
we as to the nature of this large book? The next sign is C2.
What do you make of that, Watson?"

"Chapter the second, no doubt."

"Hardly that, Watson. You will, I am sure, agree with me
that if the page be given, the number of the chapter is immaterial.
Also that if page 534 finds us only in the second chapter,
the length of the first one must have been really intolerable."

"Column!" I cried.

"Brilliant, Watson. You are scintillating this morning. If it is
not column, then I am very much deceived. So now, you see, we
begin to visualize a large book printed in double columns
which are each of a considerable length, since one of the words
is numbered in the document as the two hundred and ninety-
third. Have we reached the limits of what reason can supply?"

"I fear that we have."

"Surely you do yourself an injustice. One more coruscation,
my dear Watson -- yet another brain-wave! Had the volume been
an unusual one, he would have sent it to me. Instead of that, he
had intended, before his plans were nipped, to send me the clue
in this envelope. He says so in his note. This would seem to
indicate that the book is one which he thought I would have no
difficulty in finding for myself. He had it -- and he imagined that
I would have it, too. In short, Watson, it is a very common book."

"What you say certainly sounds plausible."

"So we have contracted our field of search to a large book,
printed in double columns and in common use."

"The Bible!" I cried triumphantly.

"Good, Watson, good! But not, if I may say so, quite good enough!
Even if I accepted the compliment for myself I could hardly name
any volume which would be less likely to lie at the elbow of one
of Moriarty's associates. Besides, the editions of Holy Writ are