have only one niece--Lady Shalford."

"And how old is she?"

He hesitated for a few moments. Then he answered.

"Oh! She must be about thirty-five. She married Shalford about ten
years ago, and she lives at Wickenham Grange, near Malton, in
Yorkshire."

"And you have no other niece?"

"None--I assure you. But why do you ask such a question? You puzzle
me."

"Not more than you puzzle me, Mr. De Gex," I replied with pique. "It
would be so much easier if you would be frank and open with me."

"My dear sir, you seem to me to have a bee in your bonnet about
something or other. Tell me, now, what is it?"

"Simply that you know me very well, but you deny it. You never thought
that I should make this unwelcome reappearance."

"Your appearance here as a mad-brained person is certainly
unwelcome," he retorted. "You first tell me that you visited me at
Stretton Street. Well, you may have been in the servants' quarters for
all I know, and----"

"Please do not be insulting!" I cried angrily.

"I have no intention of offering you an insult, sir, but your attitude
is so very extraordinary! You speak of a girl named Engledue--that was
the name, I think--and allege that she is my niece. Why?"

"Because the young lady is dead--she died under most suspicious
circumstances. And you know all about it!" I said bluntly.

"Oh! perhaps you will allege that I am a murderer next!" he laughed,
as though enjoying the joke.

"It is no laughing matter!" I cried in fury.

"Why not? I find all your allegations most amusing," and across his
dark handsome face there spread a good-humoured smile.

His was a face that I could never forget. At one moment its expression
was kindly and full of _bonhomie_, the next it was hard and
unrelenting--the face of an eccentric criminal.

"To me they are the reverse of amusing," I said. "I allege that on the
night of Wednesday, November the seventh last, I was passing your
house in Stretton Street, Park Lane, when your man, Horton, invited me
inside, and--well, well--I need not describe what occurred there, for
you recollect only too vividly--without a doubt. But what I demand to
know is why you asked me in, and what happened to me after you gave me
that money?"

"Money! I gave you money?" he cried. "Why, man alive, you're dreaming!
_You must be!_"

"I'm not dreaming at all! It is a hard fact. Indeed, I still have the
money--five thousand pounds in bank notes."

Oswald De Gex looked at me stra