you
found two visiting cards. How do you know which card was that of the
murdered man?"

The American, before he answered, waited until the chorus of
exclamations had ceased. Then he continued as though he had not been
interrupted.

"The instant I read the names upon the cards," he said, "I ran to the
screen and, kneeling beside the dead man, began a search through his
pockets. My hand at once fell upon a card-case, and I found on all
the cards it contained the title of the Earl of Chetney. His watch and
cigarette-case also bore his name. These evidences, and the fact of his
bronzed skin, and that his cheekbones were worn with fever, convinced
me that the dead man was the African explorer, and the boy who had fled
past me in the night was Arthur, his younger brother.

"I was so intent upon my search that I had forgotten the servant, and
I was still on my knees when I heard a cry behind me. I turned, and saw
the man gazing down at the body in abject horror.

"Before I could rise, he gave another cry of terror, and, flinging
himself into the hall, raced toward the door to the street. I leaped
after him, shouting to him to halt, but before I could reach the hall he
had torn open the door, and I saw him spring out into the yellow fog. I
cleared the steps in a jump and ran down the garden walk but just as
the gate clicked in front of me. I had it open on the instant, and,
following the sound of the man's footsteps, I raced after him across the
open street. He, also, could hear me, and he instantly stopped running,
and there was absolute silence. He was so near that I almost fancied I
could hear him panting, and I held my own breath to listen. But I could
distinguish nothing but the dripping of the mist about us, and from far
off the music of the Hungarian band, which I had heard when I first lost
myself.

"All I could see was the square of light from the door I had left open
behind me, and a lamp in the hall beyond it flickering in the draught.
But even as I watched it, the flame of the lamp was blown violently to
and fro, and the door, caught in the same current of air, closed slowly.
I knew if it shut I could not again enter the house, and I rushed madly
toward it. I believe I even shouted out, as though it were something
human which I could compel to obey me, and then I caught my foot against
the curb and smashed into the sidewalk. When I rose to my feet I was
dizzy and half stunned, and though I thought then that I