"The door is locked, the window is
inaccessible. Was it through the chimney?"

"The grate is much too small," he answered. "I had already considered
that possibility."

"How then?" I persisted.

"You will not apply my precept," he said, shaking his head. "How often
have I said to you that when you have eliminated the impossible
whatever remains, HOWEVER IMPROBABLE, must be the truth? We know that
he did not come through the door, the window, or the chimney. We also
know that he could not have been concealed in the room, as there is no
concealment possible. Whence, then, did he come?"

"He came through the hole in the roof," I cried.

"Of course he did. He must have done so. If you will have the kindness
to hold the lamp for me, we shall now extend our researches to the room
above,--the secret room in which the treasure was found."

He mounted the steps, and, seizing a rafter with either hand, he swung
himself up into the garret. Then, lying on his face, he reached down
for the lamp and held it while I followed him.

The chamber in which we found ourselves was about ten feet one way and
six the other. The floor was formed by the rafters, with thin
lath-and-plaster between, so that in walking one had to step from beam
to beam. The roof ran up to an apex, and was evidently the inner shell
of the true roof of the house. There was no furniture of any sort, and
the accumulated dust of years lay thick upon the floor.

"Here you are, you see," said Sherlock Holmes, putting his hand against
the sloping wall. "This is a trap-door which leads out on to the roof.
I can press it back, and here is the roof itself, sloping at a gentle
angle. This, then, is the way by which Number One entered. Let us see
if we can find any other traces of his individuality."

He held down the lamp to the floor, and as he did so I saw for the
second time that night a startled, surprised look come over his face.
For myself, as I followed his gaze my skin was cold under my clothes.
The floor was covered thickly with the prints of a naked foot,--clear,
well defined, perfectly formed, but scarce half the size of those of an
ordinary man.

"Holmes," I said, in a whisper, "a child has done the horrid thing."

He had recovered his self-possession in an instant. "I was staggered
for the moment," he said, "but the thing is quite natural. My memory
failed me, or I should have been able to foretell it. There is nothing
more to be learn