"Why," said he, "should not these unaccountable appearances be simply phenomena of vegetation?" "What do you mean?" asked Barbicane quickly. "Do not excite yourself, my worthy president," replied Michel; "might it not be possible that the dark lines forming that bastion were rows of trees regularly placed?" "You stick to your vegetation, then?" said Barbicane. "I like," retorted Michel Ardan, "to explain what you savants cannot explain; at least my hypothesis has the advantage of indicating why these rifts disappear, or seem to disappear, at certain seasons." "And for what reason?" "For the reason that the trees become invisible when they lose their leaves, and visible when they regain them." "Your explanation is ingenious, my dear companion," replied Barbicane, "but inadmissible." "Why?" "Because, so to speak, there are no seasons on the moon's surface, and that, consequently, the phenomena of vegetation of which you speak cannot occur." Indeed, the slight obliquity of the lunar axis keeps the sun at an almost equal height in every latitude. Above the equatorial regions the radiant orb almost invariably occupies the zenith, and does not pass the limits of the horizon in the polar regions; thus, according to each region, there reigns a perpetual winter, spring, summer, or autumn, as in the planet Jupiter, whose axis is but little inclined upon its orbit. Illustration: HE COULD DISTINGUISH NOTHING BUT DESERT BEDS. What origin do they attribute to these rifts? That is a question difficult to solve. They are certainly anterior to the formation of craters and circles, for several have introduced themselves by breaking through their circular ramparts. Thus it may be that, contemporary with the latter geological epochs, they are due to the expansion of natural forces. But the projectile had now attained the 40° of lunar lat., at a distance not exceeding 400 miles. Through the glasses objects appeared to be only four miles distant.