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."