y first experiments for
getting hold of the letter, and that queer inscription which I had copied
out of the pocketbook:

"MEM. 5 ALONG. 4 ACROSS."

It was the measurement most likely of something, and he was afraid of
forgetting it; therefore it was something important. Query--something
about himself? Say "5" (inches) "along"--he doesn't wear a wig. Say "5"
(feet) "along"--it can't be coat, waistcoat, trousers, or underclothing.
Say "5" (yards) "along"--it can't be anything about himself, unless he
wears round his body the rope that he's sure to be hanged with one of
these days. Then it is _not_ something about himself.

What do I know of that is important to him besides? I know of nothing but
the Letter. Can the memorandum be connected with that? Say, yes. What do
"5 along" and "4 across" mean, then? The measurement of something he
carries about with him? or the measurement of something in his room? I
could get pretty satisfactorily to myself as far as that; but I could get
no further.

Tom came back to the office, and reported him mounted for his ride. His
friend had never appeared. I sent the boy off, with his proper
instructions, on Sam's back--wrote an encouraging letter to Mr. Frank to
keep him quiet--then slipped into the inn by the back way a little before
half-past ten. The head chambermaid gave me a signal when the landing was
clear. I got into his room without a soul but her seeing me, and locked
the door immediately.

The case was, to a certain extent, simplified now. Either Mr. Davager had
ridden out with the letter about him, or he had left it in some safe
hiding-place in his room. I suspected it to be in his room, for a reason
that will a little astonish you--his trunk, his dressing-case, and all the
drawers and cupboards, were left open. I knew my customer, and I thought
this extraordinary carelessness on his part rather suspicious.

Mr. Davager had taken one of the best bedrooms at the Gatliffe Arms. Floor
carpeted all over, walls beautifully papered, four-poster, and general
furniture first-rate. I searched, to begin with, on the usual plan,
examining everything in every possible way, and taking more than an hour
about it. No discovery.

Then I pulled out a carpenter's rule which I had brought with me. Was
there anything in the room which--either in inches, feet, or
yards--answered to "5 along" and "4 across"? Nothing. I put the rule back
in my pocket--measurement was no good, evidently. Was