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Show AT THE EARTH'S CENTER.' There Is Intolerable Heat, Hut Probably No Direct Communication. The workmen in the deepest mines of Europe swelter in almost intolerable intoler-able heat, and yet they have never penetrated over one seven-thousandth I part of tho distance from the surface to the center of the earth. In the lower low-er levels of some of the Comstock mines the men fought scalding water, and could labor only throe or four hours at a time until tho Sutro tunnel pierced the mines and drew off some of the terrible heat, which had stood at 120 degrees. Tho deepest boarlng ever made, that at Sperenberg, near Berlin, penetrates only 4,172 feet, about 1,000 feet deeper than the fnm-ous fnm-ous artesian well at St IxMiis. While borings and mines reveal to us only a few secrets relating Bolely to the temperature tem-perature and constitution of tho earth for a few thousand feet below tho surface, sur-face, we are able, by means of volcanoes, vol-canoes, to form some notion of what is going on at greater depths. There have been many theories about the causes of volcanoes, Buys Goldthwaito's Geographical Magazine, but it is now generally held that though they aro produced by tho intenso heat of the interior in-terior of tho earth they are not directly connected with tho molten mass that lies' many miles below tho immediate sources of volcanic energy. Everybody Every-body knows that many rocks are formed form-ed on the floor of tho ocean, and it has been found that a twentieth to u seventh of their weight is made up of imprisoned water. Now, these rocks are buried, in time, under overlaying strata which nerve as a blanket to keep In the enormous heat of the interior. in-terior. This heat turns the water into superheated steam, which melts tho hardest rocks, and when tho steam finds a fissure in tho strata above it breaks through to the surface with terrific energy, and we have a volcano. Wo find that ihcso outpourings that have lain for countless ages many thousands of feet below tho surface aro well adapted to serve the purposes of a man. Many a vineyard flourishes on the volcanic ashes from Vesuvius, and volcanic mud has clothed the hills of Now Zealand with fine forests and its plains with luxuriant verdure. The most wonderful display of tho results of volcanic energy is seen in the northwestern corner of our own land, a region of lofty forests and of great fertility. |