Page:Popular Science Monthly Volume 19.djvu/534

518 dark-blue of the sky in which it floats, the painted revelation of the wonders of a sister world. Plainer than words, this colored image tells the story of an activity of tempests, and bubbling caldrons of fire long since burned out; of oceans evaporated and drawn into the deepest depths of a dying world—of present silence and empty desolation!

Encouraged by the approval of famous scientists, who have examined and testified to the correctness and beauty of this first phase of the moon, Mr. Harrison has completed a second phase, and is at work on the remaining pictures, which are in various stages of progression.

Among the prominent features represented as seen on the telescopic moon at the first quarter may be mentioned the Mare Crisium, one of the darkest of all the regularly bordered mares or dark plains. Crisium shows a surface of a gray tint tinged with green. At times it is curiously dotted and streaked with light. The floor is traversed by ridges crossing each other and throwing up small peaks. At the first quarter appears Messier, on the terminator of the three-days-old crescent. Messier is a fine crater-plain, nine miles in diameter, inclosed by a bright mountain-wall. To the southeast rise the walls of Catharina, in some places reaching a height of sixteen thousand feet above the interior plain, which, under the highest magnifying power, shows a surface broken up into mounds, ridges, hills, and craterlets.

Lying to the northwest appears the Mare Fœcunditatis, the largest of the western mares or sea-beds, covering an area of one hundred and sixty thousand square miles, and penetrating, in bay-like indentations, into the mountain-ranges southward. Mare Tranquillitatis and Serenitatis, the latter one of the most prominent gray plains seen at the first quarter. The entire central portion of this mare shows a decided light-green tinge.

At the last quarter the most striking feature is Copernicus, the grandest ring-plain on the northern quadrant, and one of the most instructive. Its vast walls rise nearly twelve thousand feet above the level of the plateau, showing fifty magnificent peaks that shine at certain seasons like a crown of pearls on a radiant background. The central cones attain a height of nearly three thousand feet. On the inner side the walls fall abruptly in terraces to the floor, while, without, they slope gradually, and are broken into confused ridges, spreading away from their bases into hill and mountain chains.

Aristarchus, a brilliant ring-plain, is also visible at the last quarter; its broad, terraced walls rise twenty-six hundred feet above the moon's surface, and seven thousand five hundred above its own interior floor, nearly in the center of which stand two peaks and a small crater, the central peak being the most brilliant point visible on the moon. Among the bays, so called, seen on this quarter, is the Sinus Iridum, a dark, semicircular level, bordered by the magnificent cliffs of one of the most stupendous highlands of the moon, whose crest sends up at