||::5::| || 2 |h |
oo oo ||::::|___ _|| | |
Traces oo || || | |
of oo oo oo | |
Footsteps|| || | |
|| || | |
|| 3 ||___________| |______________
|| || 6 | ditch
||____ ____||___________|_________________
door enclosing wall

Here is the ground plan of the pavilion. It had a ground-floor which was
reached by a few steps, and above it was an attic, with which we need
not concern ourselves. The plan of the ground-floor only, sketched
roughly, is what I here submit to the reader.

1. The Yellow Room, with its one window and its one door opening
into the laboratory.

2. Laboratory, with its two large, barred windows and its doors,
one serving for the vestibule, the other for The Yellow Room.

3. Vestibule, with its unbarred window and door opening into the
park.

4. Lavatory.

5. Stairs leading to the attic.

6. Large and the only chimney in the pavilion, serving for the
experiments of the laboratory.

The plan was drawn by Rouletabille, and I assured myself that there was
not a line in it that was wanting to help to the solution of the
problem then set before the police. With the lines of this plan and the
description of its parts before them, my readers will know as much as
Rouletabille knew when he entered the pavilion for the first time. With
him they may now ask: How did the murderer escape from The Yellow Room?
Before mounting the three steps leading up to the door of the pavilion,
Rouletabille stopped and asked Monsieur Darzac point blank:

"What was the motive for the crime?"

"Speaking for myself, Monsieur, there can be no doubt on the matter,"
said Mademoiselle Stangerson's fiance, greatly distressed. "The nails of
the fingers, the deep scratches on the chest and throat of Mademoiselle
Stangerson show that the wretch who attacked her attempted to commit a
frightful crime. The medical experts who examined these traces yesterday
affirm that they were made by the same hand as that which left its red
imprint on the wall; an enormous hand, Monsieur, much too large to go
into my gloves," he added with an