a constable in
uniform enter or leave, and that had excited public curiosity. I hoped
that Ambler Jevons would not delay, for I intended that he should be
first in the field. If ever he had had a good mystery before him this
certainly was one. I knew how keen was his scent for clues, and how
carefully and ingeniously he worked when assisting the police to get
at the bottom of any such affair.

He came a little after nine in hot haste, having driven from
Hammersmith in a hansom. I was upstairs when I heard his deep cheery
voice crying to the inspector from Scotland Yard:

"Hulloa, Thorpe. What's occurred? My friend Doctor Boyd has just wired
to me."

"Murder," responded the inspector. "You'll find the doctor somewhere
about. He'll explain it all to you. Queer case--very queer case, sir,
it seems."

"Is that you, Ambler?" I called over the banisters. "Come up here."

He came up breathlessly, two steps at a time, and gripping my hand,
asked:

"Who's been murdered?"

"Old Mr. Courtenay."

"The devil!" he ejaculated.

"A most mysterious affair," I went on. "They called me soon after
three, and I came down here, only to find the poor old gentleman stone
dead--stabbed to the heart."

"Let me see him," my friend said in a sharp business-like tone, which
showed that he intended to lose no time in sifting the matter. He had
his own peculiar methods of getting at the bottom of a mystery. He
worked independently, and although he assisted the police and was
therefore always welcomed by them, his efforts were always apart, and
generally marked by cunning ingenuity and swift logical reasoning that
were alike remarkable and marvellous.

I gave him a brief terse outline of the tragedy, and then, unlocking
the door of the room where the dead man still lay in the same position
as when discovered, allowed him in.

The place was in darkness, so I drew up the Venetian blinds, letting
in the grey depressing light of the wintry morning.

He advanced to the bed, stood in the exact spot where I had stood, and
where without doubt the murderer had stood, and folding his arms gazed
straight and long upon the dead man's features.

Then he gave vent to a kind of dissatisfied grunt, and turned down the
coverlet in order to examine the wound, while I stood by his side in
silence.

Suddenly he swung round on his heel, and measured the paces between
the bed and the door. Then he went to the window and looked out;
afterwards making