now that we have proofs that he is neither under
restraint nor dead, how can we stay in the house?"

"It doesn't matter," said Lupin, absently. "It doesn't matter whether
the house is guarded or not. Daubrecq has been; therefore the crystal
stopper is no longer here."

He had not finished the sentence, when a question quite naturally forced
itself upon his mind. If the crystal stopper was no longer there, would
this not be obvious from some material sign? Had the removal of that
object, doubtless contained within another object, left no trace, no
void?

It was easy to ascertain. Lupin had simply to examine the writing-desk,
for he knew, from Sebastiani's chaff, that this was the spot of the
hiding-place. And the hiding-place could not be a complicated one,
seeing that Daubrecq had not remained in the study for more than twenty
seconds, just long enough, so to speak, to walk in and walk out again.

Lupin looked. And the result was immediate. His memory had so faithfully
recorded the picture of the desk, with all the articles lying on it,
that the absence of one of them struck him instantaneously, as
though that article and that alone were the characteristic sign which
distinguished this particular writing-table from every other table in
the world.

"Oh," he thought, quivering with delight, "everything fits in!
Everything! ... Down to that half-word which the torture drew from
Daubrecq in the tower at Mortepierre! The riddle is solved. There
need be no more hesitation, no more groping in the dark. The end is in
sight."

And, without answering the inspector's questions, he thought of
the simplicity of the hiding-place and remembered Edgar Allan Poe's
wonderful story in which the stolen letter, so eagerly sought for, is,
in a manner of speaking, displayed to all eyes. People do not suspect
what does not appear to be hidden.

"Well, well," said Lupin, as he went out, greatly excited by his
discovery, "I seem doomed, in this confounded adventure, to knock up
against disappointments to the finish. Everything that I build crumbles
to pieces at once. Every victory ends in disaster."

Nevertheless, he did not allow himself to be cast down. On the one hand,
he now knew where Daubrecq the deputy hid the crystal stopper. On the
other hand, he would soon learn from Clarisse Mergy where Daubrecq
himself was lurking. The rest, to him, would be child's play.

The Growler and the Masher were waiting for him in the drawing-room