business? It had the flavor of treachery about it; yet it seemed the
only possible chance to come upon the secret springs of his acts, to
come in touch with the tools and accomplices in his crime. And the
unknown mission, that had brought Henry to his death? How was I to play
his part in that? And even if I could take his place, how was I to
serve the mysterious employer and Doddridge Knapp at the same time,
when Doddridge Knapp was ready to murder me to gain the Unknown's
secret.

Fatigue and loss of sleep deepened the dejection of mind that oppressed
me with these insistent questions, and as I vainly struggled against
it, carried me at last into the oblivion of dreamless slumber.

The next I knew I was awaking to the sound of breaking glass. It was
dark but for a feeble light that came from the window. Every bone in my
body ached from the cramped position in which I had slept, and it
seemed an age before I could rouse myself to act. It was, however, but
a second before I was on my feet, revolver in hand, with the desk
between me and a possible assailant.

Silence, threatening, oppressive, surrounded me as I stood listening,
watching, for the next move. Then I heard a low chuckle, as of some one
struggling to restrain his laughter; and so far from sympathizing with
his mirth, I was tempted to try the effect of a shot as an assistance
in suppressing it.

"I thought the transom was open," said a low voice, which still seemed
to be struggling with suppressed laughter.

"I guess it woke him up," said another and harsher voice. "I heard a