get out of the cells of the
Depot, nor out of the Palais!... Well, now--to carry off Dollon, dead
or living, by way of the Palais Square, or by the boulevard, is out of
the question: there are too many people about!... To carry him off by
one of the exits, on to either of the quays, is equally out of the
question: there are the sentries, in the first place, and then comes the
Seine--then Jacques Dollon has left the Depot, or he has not, or, at any
rate, he is still somewhere in the Palais--unless ..."

Fandor interrupted his cogitations to light a cigarette: smoking helped
him to think things out:

"It is equally certain that if Dollon is still in the Palais, he cannot
be in the Depot, for the Depot has been rigorously searched since his
disappearance, and he would most certainly have been found, had he been
anywhere about the Depot. It is also certain that he is not inside the
Palais, because the only means of communication between the Depot and
the Palais is a single staircase, and it is certain that a corpse could
not have been taken that way unperceived.... Then it follows that
Jacques Dollon must have got out by the only ways which are in
communication with the Depot: that is to say, the drains and the
chimneys!"

"How could he have got out, or been got out by the drains? As far as I
know, there is no system of pipes large enough to allow of the passage
of a man through the pipes which join the main sewers; but, as a set-off
to that, there is a chimney--the ancient chimney of Marie
Antoinette--which communicates with the Depot, and the roof I am now on:
it must have been by this chimney that the escape was made! Let us see
whether this is so or not!"

By the light of his tiny dark lantern Fandor studied afresh the plan of
the Palais, and tried to identify the various chimneys about him. He
soon picked out the orifice of Marie Antoinette's chimney. After a
considering glance at it, he remarked:

"That's odd! Here is the only chimney whose opening is below the ledge
of the roofs! It is certain that unless one had been warned, and had
examined this roof from some neighbouring building, the orifice of this
chimney would not be noticed. If Jacques Dollon passed out by it, no one
would notice his exit!"

Our journalist continued his examination, full of excitement. Surely he
was on the right track!

"Ah! Ah! Here are stones freshly scraped and scratched!" he cried
delightedly. "And this white mark is just the ki