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 to in Latin by present day astronomers. Translated, however, they add a quaint glamour to the Gray Land and the eye wanders interestedly over "The Sea of Showers," "The Sea of Tranquillity," "The Sea of Clouds," "The Sea of Nectar," "The Gulf of Dews," "The Ocean of Storms," "The Bay of Rainbows," "The Marsh of Sleep" or "The Lake of Dreams."

Since the days of Galileo, improved telescopes and continued research have constantly increased our knowledge of the moon. The curious so-called "seas" are not, seemingly, old sea-bottoms; they are dark plains on the lunar surface much more likely to be great lava plains than sea-basins, according to the evidence that has been collected. Many scientists now regard these areas as a part of the surface where the thin crust became weakened and succumbed in an early stage of the moon's development; the lava then welled forth from the interior and flowed out in great molten sheets over the surrounding country. Since over 100,000 craters have also been observed on this side of the moon, all in fairly good condition, and since there has been no weathering, it is sometimes said that the moon presents a picture of the volcanic age petrified.

The gray patches are best seen when the moon is full. Under a telescope these areas appear darker with occasional traces of yellow or green tints. The colors may be due to some form of vegetation or masses of colored volcanic material.

The most prominent mountains on the moon are the Apennines. These extend in a continuous curve for 450 miles a little north of the center of the moon, forming an impressive "shoreline" for Mare Imbrium, the "Sea of Showers." Running northward, just above the Apennines, is the Caucasus range, and east of the Caucasus, lie the Alps. The Alps and Caucasus mountains are