One day he was sitting on the balcony after evening tea, reading. At the same time, in the drawing-room, Tanya taking soprano, one of the young ladies a contralto, and the young man with his violin, were practising a well-known serenade of Braga's. Kovrin listened to the words--they were Russian--and could not understand their meaning. At last, leaving his book and listening attentively, he understood: a maiden, full of sick fancies, heard one night in her garden mysterious sounds, so strange and lovely that she was obliged to recognise them as a holy harmony which is unintelligible to us mortals, and so flies back to heaven. Kovrin's eyes began to close. He got up, and in exhaustion walked up and down the drawing-room, and then the dining-room. When the singing was over he took Tanya's arm, and with her went out on the balcony. "I have been all day thinking of a legend," he said. "I don't remember whether I have read it somewhere or heard it, but it is a strange and almost grotesque legend. To begin with, it is somewhat obscure. A thousand years ago a monk, dressed in black, wandered about the desert, somewhere in Syria or Arabia.... Some miles from where he was, some fisherman saw another black monk, who was moving slowly over the surface of a lake. This second monk was a mirage. Now forget all the laws of optics, which the legend does not recognise, and listen to the rest. From that mirage there was cast another mirage, then from that other a third, so that the image of the black monk began to be repeated endlessly from one layer of the atmosphere to another. So that he was seen at one time in Africa, at another in Spain, then in Italy, then in the Far North.... Then he passed out of the atmosphere of the earth, and now he is wandering all over the universe, still never coming into conditions in which he might disappear. Possibly he may be seen now in Mars or in some star of the Southern Cross. But, my dear, the real point on which the whole legend hangs lies in the fact that, exactly a thousand years from the day when the monk walked in the desert, the mirage will return to the atmosphere of the earth again and will appear to men. And it seems that the thousand years is almost up.... According to the legend, we may look out for the black monk to-day or to-morrow." "A queer mirage," said Tanya, who did not like the legend. "But the most wonderful part of it all," laughed Kovrin, "is that I simply cannot recall where I got this legend from. Have I read it somewhere? Have I heard it? Or perhaps I dreamed of the black monk. I swear I don't remember. But the legend interests me. I have been thinking about it all day."