“No, apparently he was in deep earnest. But what kind of humors he was thinking of I cannot tell. Perhaps the name occurred to him because the _Mare Humorum_ is the darkest of all the great levels on the moon. It is very conspicuous to the naked eye at Full Moon. You will perceive that Tycho has now become the most prominent of all the rings on the moon. It will maintain this distinction and continue to gain in conspicuousness up to the time of Full Moon. Seen as we now see it, Tycho manifestly merits the appellation sometimes bestowed upon it of the ‘metropolitan crater of the moon.’ Notice how bright the mysterious bands radiating from it have become. The higher the sun rises upon them the more brilliantly they glow, almost as if they were streaks of new-fallen snow. They spread over the whole of the southwestern quarter of the moon, hiding rings and mountains with their brightness. One very notable ray runs down into the _Mare Nubium_, and a fainter one parallel with it produces the semblance of a long, walled way. “The South Pole of the moon lies in the midst of a marvelously upheaved and tumbled region, where one huge ring is seen breaking into another on every hand. One of these rings, named Newton—it lies just on the upper edge of the disk, south of Clavius—surrounds the deepest known depression on the moon. Its bottom sinks to a depth of 24,000 feet below the highest point on the wall. This gigantic hole is so profound that, situated where it is, close to the pole, where the sun can never rise very high, its depths remain forever buried in night. It is the very ideal of a dungeon, for if you were imprisoned at the bottom you would never see either the sun or the earth.” “You make me shudder! Truly, after all, the moon appears to be a world filled with dreadful things. Who would ever imagine it, seeing how serene and beautiful she is in a calm night?” “Yet is there not a kind of beauty even in those things, like the abyss of Newton, which appall you only when you know the real facts about them? There is a certain grace in their shapes and outlines, and a great attraction for the eye in their contrasts of light and shadow. It is the same sort of attraction which we find in such terrestrial scenes as the Yosemite Valley viewed from Inspiration Point, or the awful depths and chasms of the Grand Cañon of the Colorado. The presence of man and his works is not always essential in order to fix our attention upon the wonders of nature. Their very grandeur exalts us until we forget our little race and its ephemeral achievements.” “Still, I hope that you will show me something on the moon less awe-inspiring and suited to awaken more quiet thoughts, and especially to reassure me concerning my lunarians, as I suppose you would call them.”