Page:Popular Science Monthly Volume 56.djvu/688

672 caused by an X-ray effect on our atmosphere. The sun and the earth are separated like the terminals of a Crooke's tube—two conductors with a vacuum between. An electrical excitation from the sun may cause an electrical discharge between it and the earth. This discharge might consist of an X-ray effect which could separate the upper layers of the atmosphere into positive and negative charges. The velocity of the negatively charged particles is greater than that of the positively charged ones, and the revolution of the earth may cause such a movement of these electrified particles that electrical currents may be generated which in circulation around the earth could produce the observed magnetism of the north and south poles, together with the auroral lights characteristic of those regions. This, I am well aware, is an audacious theory. It is certainly a vast extension of the laboratory experiments I have described, but the electrical radiations developed in electrical discharges are as competent to produce powerful magnetic whirls as the heat radiations in our atmosphere to develop cyclones. In the lower regions of our atmosphere the air is an insulator like glass to the passage of an electrical current. A layer a foot thick can prevent the circulation of the most powerful current which is now used to generate horse power. When this air space is rarefied at a certain degree of rarefaction the electrical current passes, especially, as we have seen, if it is illuminated by the X rays. When, therefore, we ascend to a height of ten or twenty miles the rarefied air becomes an excellent conductor of electricity of high electro-motive force. To my mind the conditions exist for developing an electrical state in the earth's covering of air, which is competent to explain the electrical manifestations of the air, the auroral gleam, and the mysterious effect on the magnetic needle which keeps it directed to the magnetic north. Can not we conclude that the study of the X rays bids fair to greatly extend our conceptions of the constitution of matter and of the action and interaction of Nature's forces?

explorer reported, a few years ago, that he had seen, from one of the lofty summits of the Mount Everest district, a peak which, beheld in the same view with Mount Everest, was evidently higher than it. Nothing has been heard of the matter since then till the recent appearance of Major L. A. Waddell's book, Among the Himalayas. This author, who has explored the same region, represents that the Tibetans there say there is another mountain, due north of Mount Everest, that exceeds that peak in height, thus confirming the story of the former Alpinist. It appears that Mount Everest is not called Gaurisankar or Deodunga, as some affirm, but that the Tibetan name of the culminating peak of the group is Jomo-kang-har—"The Lady White Glacier."