"Do not misunderstand me," he added. "I refer not to the transport of his wares to Suez, to Zagazig, to Mecca, to Aleppo, to Baghdad, Damascus, Kandahar, and Pekin; although the whole of these vast enterprises is entrusted to none other than the only son of my father: I speak, now, of the bearing of a small though heavy box from the great magazine and manufactory of Mohammed er-Rahmân at Shubra, to his shop in the Sûk el-Attârin, a matter which I have arranged for him on the eve of the Molid en-Nebi (birthday of the Prophet) for the past five-and-thirty years. Every one of my porters to whom I might entrust this special charge is otherwise employed; hence my observation that it was written how none other than yourself should pass beneath this window at a certain fortunate hour." Fortunate indeed had that hour been for me, and my pulse beat far from normally as I put the question: "Why, O Father Abdul, do you attach so much importance to this seemingly trivial matter?" The face of Abdul the Porter, which resembled that of an intelligent mule, assumed an expression of low cunning. "The question is well conceived," he said, raising a long forefinger and wagging it at me. "And who in all Cairo knows so much of the secrets of the great as Abdul the Know-all, Abdul the Taciturn! Ask me of the fabled wealth of Karafa Bey and I will name you every one of his possessions and entertain you with a calculation of his income, which I have worked out in _nûss-faddah_![B] Ask me of the amber mole upon the shoulder of the Princess Azîza and I will describe it to you in such a manner as to ravish your soul! Whisper, my son"--he bent towards me confidentially--"once a year the merchant Mohammed er-Rahmân prepares for the Lady Zuleyka a quantity of the perfume which impious tradition has called 'Breath of Allah.' The father of Mohammed er-Rahmân prepared it for the mother of the Lady Zuleyka and his father before him for the lady of that day who held the secret--the secret which has belonged to the women of this family since the reign of the Khalîf el-Hakîm from whose favorite wife they are descended. To her, the wife of the Khalîf, the first _dirhem_ (drachm) ever distilled of the perfume was presented in a gold vase, together with the manner of its preparation, by the great wizard and physician Ibn Sina of Bokhara" (Avicenna). [B] A _nûss-faddah_ equals a quarter of a farthing. "You are well called Abdul the Know-all!" I cried in admiration. "Then the secret is held by Mohammed er-Rahmân?" "Not so, my son," replied Abdul. "Certain of the essences employed are brought, in sealed vessels, from the house of the Lady Zuleyka, as is also the brass coffer containing the writing of Ibn Sina; and throughout the measuring of the quantities, the secret writing never leaves her hand." "What, the Lady Zuelyka attends in person?" Abdul the Porter inclined his head serenely.