the window shut, the goods were not stolen by the
chance of a chambermaid or a boots coming along. Whoever did the job
went after it special; and he ain't going to part with his swag without
his price. This must be a case of notice to the pawnbrokers. There's
one good thing about it, anyhow, that the hue and cry needn't be given.
We needn't tell Scotland Yard unless you like; we can work the thing
privately. If you wish to keep the thing dark, as you told me at the
first, that is our chance." Mr. Corbeck, after a pause, said quietly:

"I suppose you couldn't hazard a suggestion as to how the robbery was
effected?" The Policeman smiled the smile of knowledge and experience.

"In a very simple way, I have no doubt, sir. That is how all these
mysterious crimes turn out in the long-run. The criminal knows his
work and all the tricks of it; and he is always on the watch for
chances. Moreover, he knows by experience what these chances are likely
to be, and how they usually come. The other person is only careful; he
doesn't know all the tricks and pits that may be made for him, and by
some little oversight or other he falls into the trap. When we know
all about this case, you will wonder that you did not see the method of
it all along!" This seemed to annoy Mr. Corbeck a little; there was
decided heat in his manner as he answered:

"Look here, my good friend, there is not anything simple about this
case--except that the things were taken. The window was closed; the
fireplace was bricked up. There is only one door to the room, and that
I locked and bolted. There is no transom; I have heard all about hotel
robberies through the transom. I never left my room in the night. I
looked at the things before going to bed; and I went to look at them
again when I woke up. If you can rig up any kind of simple robbery out
of these facts you are a clever man. That's all I say; clever enough
to go right away and get my things back." Miss Trelawny laid her hand
upon his arm in a soothing way, and said quietly:

"Do not distress yourself unnecessarily. I am sure they will turn up."
Sergeant Daw turned to her so quickly that I could not help remembering
vividly his suspicions of her, already formed, as he said:

"May I ask, miss, on what you base that opinion?"

I dreaded to hear her answer, given to ears already awake to suspicion;
but it came to me as a new pain or shock all the same:

"I cannot tell you how I know.