I was prevented last night from sleeping by the perpetual recurrence in my reveries of the name of Lady Silver-Voice. I had forgotten her existence, as one is apt to forget a beautiful thing amidst the material cares of this life. Let me endeavor to tell her story as simply as it was told to me. But first, how I came to see her--for I have had that privilege. It was one evening in winter-time, that, after a prolonged illness, I was taking a stroll on the roof of a palace-like mansion in Cairo. The sun had set _for me_; it had gone down behind the interminable sea of houses. But I could still see it shining on the forest of minarets that rose through the moist, balmy air, and on the vast dome of the mosque that now towers above the citadel. The terrace-roof on which I was, though commanded at a distance by much more lofty buildings, was far raised above the humble dwellings near at hand, so that I could look down and observe the movements of my neighbors, who were most varied in race and costume--Turks and Maltese, Arabs and Greeks, Armenians and Copts--to say nothing of "Jews and poultry," which my servant, who brought me a pipe, added to the enumeration. I passed some time in examining the movements of these various personages, who all come out upon their terraces to enjoy the evening air; and though I did not observe any thing very characteristic, any thing which would necessarily go down in my journal, I was sufficiently interested not to notice the flight of time, and to allow complete darkness to gather round me while I still leaned over the parapet. Suddenly I was aroused from my contemplations by a snatch of a strange song sung in the most marvelously-sweet voice I had ever heard. I started, not exactly like a guilty thing, but transfixed, as it were, by an almost painful shaft of delight. The voice swelled up on the night air, until, in spite of its divine sweetness, it became almost a cry of sorrow, and then ceased, leaving a thrill running through my frame that gradually seemed to shrink back to my heart, and expire there in a feeling of mingled joy and pain. Perhaps the state of my health rendered me peculiarly susceptible of strong emotions: I am afraid I wept. The darkness, however, prevented this weakness from being witnessed by Ali, who came to announce that my dinner was ready. I went down the winding staircase to the vast lonely hall, where I usually ate alone--the master of the house being absent on a journey; but though my appetite was that of a convalescent, I am sure I did not enliven the meal for myself by my usual humorous observations: to the officer, for example, that I was doubtful whether the beef was camel, or the mutton was donkey. Ali seemed rather surprised, especially when I asked him, abruptly, who it was that sang so sweetly in the neighborhood.