This opinion of Schmidt's, shared by Beer and Maedler, Barbican's observations now convinced him to be far better founded than that of certain astronomers who admit of no color at all being visible on the Moon's surface but gray. In certain spots the greenish tint was quite decided, particularly in _Mare Serenitatis_ and _Mare Humorum,_ the very localities where Schmidt had most noticed it. Barbican also remarked that several large craters, of the class that had no interior cones, reflected a kind of bluish tinge, somewhat like that given forth by a freshly polished steel plate. These tints, he now saw enough to convince him, proceeded really from the lunar surface, and were not due, as certain astronomers asserted, either to the imperfections of the spy-glasses, or to the interference of the terrestrial atmosphere. His singular opportunity for correct observation allowed him to entertain no doubt whatever on the subject. Hampered by no atmosphere, he was free from all liability to optical illusion. Satisfied therefore as to the reality of these tints, he considered such knowledge a positive gain to science. But that greenish tint--to what was it due? To a dense tropical vegetation maintained by a low atmosphere, a mile or so in thickness? Possibly. But this was another question that could not be answered at present. Further on he could detect here and there traces of a decidedly ruddy tint. Such a shade he knew had been already detected in the _Palus Somnii_, near _Mare Crisium_, and in the circular area of _Lichtenberg_, near the _Hercynian Mountains_, on the eastern edge of the Moon. To what cause was this tint to be attributed? To the actual color of the surface itself? Or to that of the lava covering it here and there? Or to the color resulting from the mixture of other colors seen at a distance too great to allow of their being distinguished separately? Impossible to tell. Barbican and his companions succeeded no better at a new problem that soon engaged their undivided attention. It deserves some detail. Having passed _Lambert_, being just over _Timocharis_, all were attentively gazing at the magnificent crater of _Archimedes_ with a diameter of 52 miles across and ramparts more than 5000 feet in height, when Ardan startled his companions by suddenly exclaiming: "Hello! Cultivated fields as I am a living man!" "What do you mean by your cultivated fields?" asked M'Nicholl sourly, wiping his glasses and shrugging his shoulders. "Certainly cultivated fields!" replied Ardan. "Don't you see the furrows? They're certainly plain enough. They are white too from glistening in the sun, but they are quite different from the radiating streaks of _Copernicus_. Why, their sides are perfectly parallel!" "Where are those furrows?" asked M'Nicholl, putting his glasses to his eye and adjusting the focus.