“This is not all.  In certain seasons these canals become double.  This phenomenon seems to appear at a determinate epoch, and to be produced simultaneously over the entire surface of the planet’s continents.  There was no indication of it in 1877, during the weeks that preceded and followed the summer solstice of that world.  A single isolated case presented itself in 1879.  On the 26th of December, this year—­a little before the spring equinox, which occurred on Mars on the 21st of January, 1880—­I noticed the doubling of the Nile [a canal thus named] between the Lakes of the Moon and the Ceraunic Gulf.  These two regular, equal, and parallel lines caused me, I confess, a profound surprise, the more so because a few days earlier, on the 23d and the 24th of December, I had carefully observed that very region without discovering anything of the kind.

“I awaited with curiosity the return of the planet in 1881, to see if an analogous phenomenon would present itself in the same place, and I saw the same thing reappear on the 11th of January, 1882, one month after the spring equinox—­which occurred on the 8th of December, 1881.  The duplication was still more evident at the end of February.  On this same date, the 11th of January, another duplication had already taken place, that of the middle portion of the canal of the Cyclops, adjoining Elysium. [Elysium is a part of one of the continental areas.]

“Yet greater was my astonishment when, on the 19th of January, I saw the canal Jamuna, which was then in the center of the disk, formed very rigidly of two parallel straight lines, crossing the space which separates the Niliac Lake from the Gulf of Aurora.  At first sight I believed it was an illusion, caused by fatigue of the eye and some new kind of strabismus, but I had to yield to the evidence.  After the 19th of January I simply passed from wonder to wonder; successively the Orontes, the Euphrates, the Phison, the Ganges, and the larger part of the other canals, displayed themselves very clearly and indisputably duplicated.  There were not less than twenty examples of duplication, of which seventeen were observed in the space of a month, from the 19th of January to the 19th of February.

“In certain cases it was possible to observe precursory symptoms which are not lacking in interest.  Thus, on the 13th of January, a light, ill-defined shade extended alongside the Ganges; on the 18th and the 19th one could only distinguish a series of white spots; on the 20th the shadow was still indecisive, but on the 21st the duplication was perfectly clear, such as I observed it until the 23d of February.  The duplication of the Euphrates, of the canal of the Titans, and of the Pyriphlegethon also began in an uncertain and nebulous form.