The pale daylight entered from without, throwing a sinister light on the saffron-coloured walls.

The floor--for though the laboratory and the vestibule were tiled, The Yellow Room had a flooring of wood--was covered with a single yellow mat which was large enough to cover nearly the whole room, under the bed and under the dressing-table--the only piece of furniture that remained upright.

The centre round table, the night-table and two chairs had been overturned.
These did not prevent a large stain of blood being visible on the mat, made, as Daddy Jacques informed us, by the blood which had flowed from the wound on Mademoiselle Stangerson's forehead.

Besides these stains, drops of blood had fallen in all directions, in line with the visible traces of the footsteps--large and black--of the murderer.

Everything led to the presumption that these drops of blood had fallen from the wound of the man who had, for a moment, placed his red hand on the wall.
There were other traces of the same hand on the wall, but much less distinct.
"See!--see this blood on the wall!" I could not help exclaiming.
"The man who pressed his hand so heavily upon it in the darkness must certainly have thought that he was pushing at a door! That's why he pressed on it so hard, leaving on the yellow paper the terrible evidence.