Page:Popular Science Monthly Volume 21.djvu/585

From Wikisource
Jump to: navigation, search
This page has been proofread, but needs to be validated.

Egypt, in Philistia, and Phœnicia; M. Cotteau is making his way through Russia and Siberia to Japan. M. Wiener is traveling through South America; M. Pinard, having done some work in Alaska, is engaged in California, New Mexico, and Arizona; and M. Charnay is digging in the ruins of the ancient cities of Mexico. In Europe, M. Georges Pouchet is studying the glacial fauna of Norway; M. Dieulafait is investigating the formation of rock-salts and gypsums in Switzerland; M. Milne-Edwards, as the head of a commission, is about to engage in deep-sea researches in the Mediterranean; and several parties are exploring the Alps and the Pyrenees.


Is the Moon red-hot?—Mr. W. Mattieu Williams believes that the surface of the moon has an intrinsic brilliancy of its own, and a temperature much greater than is usually supposed. He expresses the opinion, in effect, that the surface of the moon is, as it appears to be in eclipses, "of a dull red heat, and that this high temperature is due to the action of the sun's rays striking it directly, without any intervening shield of aqueous vapor or other atmospheric matter. If the volcanic tufa, of which the moon's surface is evidently composed, resembles the corresponding material on our earth, it is one of the best absorbers of heat and the worst of conductors. This being the case, the uninterrupted glare of the sun's rays would produce its maximum possible effect on a thin film of the moon's surface. . . . We must remember that a dull copperred heat, just visible in the dark, is considerably below the temperature of red heat visible in daylight. Supposing the color of the moon to be due to such heat, I should estimate its surface temperature at a little above 600º." Lord Rosse, estimating the surface temperature of the moon, concluded it was about 500º. Mr. Williams was led to his conclusion by watching the appearance of the moon during the totality of an eclipse. When the partially eclipsed moon rose, the shaded part displayed a full copper-red color; as the eclipse progressed, this advanced to a darker or more obscure copper-color; then the redness gradually faded, and the shaded portion of the moon grew darker and grayer, until at last it became of a dark slate-color; and its outline or limb was barely traceable toward the end of the eclipse. In some elementary treatises this copper-color is attributed to "the refraction of the sun's light by the action of the earth." Mr. Williams fails to see how this can operate in the middle of the shadow, where the color is the most decided, and why it should fade as the eclipse progresses, and finally be lost just at the outer edge of the shadow. The fading is easily accounted for on Mr. Williams's hypothesis, as the result of the rapid cooling of the lunar surface on the withdrawal of the sun's rays. The reasoning that ascribes so high a temperature to the side of the moon presented to the sun must lead to the conclusion that the dark, or night side, is intensely cold.


The Original Home of the Aryans.— Dr. Fligier argues in "Kosmos" that the theory of the Asiatic origin of the Aryan race is not yet as firmly settled as has been supposed. Latham disputes it on geographical grounds in his "Native Races of the Russian Empire." Pictet believes, on the evidence of the names of animals and plants that were known to them, that they originated farther north than the Asiatic theory supposes, and fixes their birthplace in Southern Russia. Benfey and Professor Tomaschek, of Grätz, agree with him, and indicate the region of the southern Volga as their primary home, whence they may have spread to the Carpathian Mountains on the west, and to the marshes of the interior and the Ural on the east. Bogdanoff has found dolichocephalous skulls of the recognized type of the German giant-graves in the Kurgans of Moscow. Resemblances between Finnish and Aryan and between Magyar and Iranian words indicate that those people were respectively neighbors to each other in their old times, as might have been the case if the theory of the European origin of the Aryans is true. Dr. Fligier believes that the results of linguistic, anthropological, and archaeological researches indicate that the Indians and the Iranians lived near each other for a long time in Eastern Europe or Northwestern Asia, and that the Indians followed the Iranians into Asia. That this happened at a comparatively late period is presumed to be shown by the fact that these