I turned away
and resumed my seat. Grooten smiled at me.

"Well, Sir Knight Errant," he said lightly; "so you could not free the
maiden?"

"I was made to feel and look like a fool, of course," I answered, "but I
don't mind about that. To tell you the truth, I am not satisfied now.
The man says that he is her guardian, and that he has just brought her
from a convent, where she has lived all her life. He vouchsafed to
explain things to me to avoid a row, but he was desperately angry. She
has never been out of the convent since she was three years old, and she
is very nervous and shy. That was his story, and he told it plausibly
enough. I could not get anything out of her, except an admission that
what he said was the truth."

Mr. Grooten nodded thoughtfully.

"After all," he said, "she is only a child, fourteen or fifteen at the
most, I should suppose. I have paid the bill, and, as you see, I have my
coat on. Are you ready?"

"Directly I have finished my coffee," I answered. "It looks too good to
leave."

"Finish it, by all means," he answered. "I am in no particular hurry.
By-the-bye, I forget whether I showed you this."

He drew a small shining weapon, with rather a long barrel, from his
pocket, but though he invited me to inspect it, he retained it in his
own hand.

"I bought it in New York a few months ago," he remarked; "it is the
latest weapon of destruction invented."

"Is it a revolver?" I asked, a little puzzled by its shape.

"Not exactly," he answered, fingering it carelessly; "it is in reality a
sort of air-gun, with a wonderful compression, and a most ingenious
silencer; quite as deadly, they say, as any firearm ever invented. It
ejects a cylindrically-shaped bullet, tapered down almost to the
fineness of a needle. Now," he added, with a faint smile and a rapid
glance round the room, "if only one dared--" he turned in his chair, and
I saw the thing steal out below his cuff, "one could free the child
quite easily--quite easily."

It was all over in a moment--a wonderful, tense moment, during which I
sat frozen to my chair, stricken dumb and motionless with the tragedy
which it seemed that I alone had witnessed. For there had been a little
puff of sound, so slight that no other ears had noticed it. The seat in
front of me was empty, and the man on my right had fallen forwards, his
hand pressed to his side, his face curiously livid, patchy with streaks
of dark colour, his eyes bulbous. Waiters st