Blaireau, indeed, after sniffing everywhere, persisted in scratching the wall where I had seen the apparition; he would start back every time his pointed nose came to a certain spot in the wainscotting; then, wagging his bushy tail with a satisfied air, he would return to his master as if to tell him to concentrate his attention on this spot.  The sergeant then began to examine the wall and the woodwork; he tried to insinuate his sword into some crack; there was no sign of an opening.  Still, a door might have been there, for the flowers carved on the woodwork would hide a skilfully constructed sliding panel.  The essential thing was to find the spring that made this panel work; but that was impossible in spite of all the efforts we made for two long hours.  In vain did we try to shake the panel; it gave forth the same sound as the others.  They were all sonorous, showing that the wainscot was not in immediate contact with the masonry.  Still, there might be a gap of only a few inches between them.  At last Marcasse, perspiring profusely, stopped, and said to me: 

“This is very stupid; if we searched all night we should not find a spring if there is none; and however hard we hammered, we could not break in the door if there happened to be big iron bars behind it, as I have sometimes seen in other old country-houses.”

“The axe might help us to find a passage,” I said, “if there is one; but why, simply because your dog scratches the wall, persist in believing that John Mauprat, or the man who resembles him, could not have come in and gone out by the door?”

“Come in, if you like,” replied Marcasse, “but gone out—­no, on my honour!  For, as the servant came down I was on the staircase brushing my boots.  As soon as I heard something fall here, I rushed up quickly three stairs at a time, and found that it was you—­like a corpse, stretched out on the floor, very ill; no one inside nor outside, on my honour!

“In that case, then, I must have dreamt of my fiend of an uncle, and the servant must have dreamt of the black cloak; for it is pretty certain that there is no secret door here; and even if there were one, and all the Mauprats, living and dead, knew the secret of it, what were that to us?  Do we belong to the police that we should hunt out these wretched creatures?  And if by chance we found them hidden somewhere, should we not help them to escape, rather than hand them over to justice?  We are armed; we need not be afraid that they will assassinate us to-night; and if they amuse themselves by frightening us, my word, woe betide them!  I have no eye for either relatives or friends when I am startled in my sleep.  So come, let us attack the omelette that these good people my tenants are preparing for us; for if we continue knocking and scratching the walls they will think we are mad.”

Marcasse yielded from a sense of duty rather than from conviction.  He seemed to attach great importance to the discovery of this mystery, and to be far from easy in his mind.  He was unwilling to let me remain alone in the haunted room, and pretended that I might fall ill again and have a fit.