g the
room in darkness save for the glow of the fire.

A deep voice cried:

"May I ask what you are all doing in my house?"

The secret door of the bookshelves had swung back and there,
framed in the gaping void, Desmond saw the dark figure of a man.

CHAPTER XIX. THE UNINVITED GUEST

There are moments in life when the need for prompt action is so
urgent that thought, decision and action must be as one operation
of the brain. In the general consternation following on the
dramatic appearance of this uninvited guest, Desmond had a brief
respite in which to think over his position.

Should he make a dash for it or stay where he was and await
developments?

Without a second's hesitation; he decided on the latter course.
With the overpowering odds against him it was more than doubtful
whether he could ever reach the library door. Besides, to go was
to abandon absolutely all hope of capturing the gang; for his
flight would warn the conspirators that the game was up. On the
other hand, the new-comer might be an ally, perhaps an emissary
of the Chief's. The strange behavior of the odd man had shown
that something was afoot outside of which those in the library
were unaware. Was the uninvited guest the deus ex machina who was
to help him, Desmond, out of his present perilous fix?

Meanwhile the stranger had stepped into the room, drawing the
secret door to behind him. Desmond heard his heavy step and the
dull thud of the partition swinging into place. The sound seemed
to break the spell that hung over the room.

Mortimer was the first to recover his presence of mind. Crying
out to No. 13 to lock the door leading into the hall, he fumbled
for a moment at the table. Desmond caught the noise of a match
being scratched and the next moment the library was again bathed
in the soft radiance of the lamp.

Picking up the light, Mortimer strode across to the stranger.

"What do you want here" he demanded fiercely, "and who the
devil..."

He broke off without completing his sentence, drawing back in
amazement. For the rays of the lamp fell upon the pale face of a
stoutish, bearded man, veering towards middle age standing in
front of Mortimer. And the face was the face of the stoutish,
bearded man, veering towards middle age, who stood in the shadow
a few paces behind Mortimer. Each man was a complete replica of
the other, save that the face of the new arrival was thin and
haggard with that yellowish tinge which comes