"If I knew his exact whereabouts," he replied, "there would be no occasion to fear him. All that I know is that he is in Cairo; and since many richly attired women of Europe and America will be here to-morrow night, of a surety Omar Ali Khân will be here also!" I shook my head in perplexity. "Omar Ali Khân?"----I began. "Ah," continued Abû Tabâh, "to you that name conveys nothing, but to me it signifies Omar of Ispahân, 'the Father of Thieves.' Do you remember," fixing his strange eyes hypnotically upon me, "the theft of the sacred _burko_ of Nefîseh?" "Quite well," I replied hastily; since the incident represented an unpleasant memory. "It was Omar of Ispahân who stole it from the shrine. It was Omar of Ispahân who stole the blue diamond of the Rajah of Bagore from the treasure-room at Jullapore, and Omar of Ispahân"--lowering his voice almost to a whisper--"who stole the Holy Carpet ere it reached Mecca!" "What!" I cried. "When did that happen? I never heard of such an episode!" Abû Tabâh raised his long, slim hand warningly. "Be cautious!" he whispered; "the flowers of the garden, the palms in the grove, the very sands of the desert have ears! The lightest word spoken in the _harêm_ of the Khedive, or breathed from a minaret of the Citadel, is heard by Omar of Ispahân! The holy covering for the Kaaba was restored, on payment of a ruinous ransom by the Sherîf of Mecca, and none save the few ever knew of its loss." For a time I was silent; words failed me; for the veil of the Kaaba, miscalled "the Carpet," is about the size of a bowling-green; then-- "In what manner does this affair concern you, Abû Tabâh?" I asked. "In this way: the daughter of the Mudîr el-Fáyûm is here, in order that she may be present on the Night of Ashûra in the Mûski. For a Moslem lady to stay in such a place as this"--there was a faint note of contempt in the speaker's voice--"is without precedent, but the circumstances are peculiar. The _khân_ near the Mosque of Hosein is full, and it is not seemly that the Mudîr's daughter should live at any lesser establishment. Therefore, as she brings her two servants, it has been possible for her to remain here. But"--his voice sank again--"her ornaments are famed throughout Islâm." I nodded comprehendingly. "To me," Abû Tabâh whispered, "has been entrusted the task of guarding them; to you, I entrust that of guarding the possessions of the other guests!" I started. "But, my friend," I said, "this is a dreadful responsibility which you impose upon me." "Other precautions are being taken," he replied calmly; "but you, observing great circumspection, can speak to the guests, and, being forewarned of his presence, can even watch for the coming of Omar of Ispahân." II The effect of my news upon Lady Collis was truly dramatic. "Oh," she cried, "my rope of pearls. Mr. Chundermeyer only told me last week that it was worth at least two hundred pound more than I gave for it."