"It is impossible," I said. "I can come to no terms with those
who shield murderers."

He regarded me fixedly, but did not move.

"Es-selam 'aleykum!" I added ("Peace be on you!") closing the
interview in the Eastern manner.

The old man lowered his eyes, and saluted me with graceful gravity.

"Wa-'aleykum!" he said ("And on you!"). I conducted him to the
door and closed it upon his exit. In his last salute I had noticed
the flashing of a ring which he wore upon his left hand, and he was
gone scarce ten seconds ere my heart began to beat furiously. I
snatched up "Assyrian Mythology" and with trembling fingers turned
to a certain page.

There I read--

Each Sheikh of the Assassins is said to be invested with the "Ring
of the Prophet." It bears a green stone, shaped in the form of a
scimitar or crescent.

My dreadful suspicion was confirmed. I knew who my visitor had
been.

"God in heaven!" I whispered. "It was Hassan of Aleppo!"