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Show Mountains Float Like Icebergs Interesting Researches Made by the United States Coast and Geodetic Survey. CHANGES GEOLOGICAL SCIENCE Mountain Masses Found to Be Due to the Presence of Lighter Material Mate-rial in Earth's Crust Under Un-der Them. Washington. Mountains float. Cubic Cu-bic yard for cubic yard, mountains weigh less, not more, than the valleys. val-leys. The mountains are held up by I the lighter material of the earth's crust flowing under them. This has been proved by researches conducted by the division of geodesy of the coast and geodetic survey, under the direction direc-tion of Dr. William Bowie, chief of the division, and his predecessor, Prof. John F. Hayford, now with Northwestern North-western university. It has been found that the earth's crust is about sixty miles in thickness, thick-ness, and near that depth, probably below, the material of the earth is yielding to forces which act for long times. The earth's crust floats on this yielding yield-ing material. If the earth's crust a? were cut into blocks by vertical planes, with the base of each block at a depth of sixty miles below sea level, and the area of the bases of the blocks were the same and as large as 100 miles square, these blocks would have the same mass; that is, they would weigh the same. Weight Is Equal. By means of the geodetic observations observa-tions by the United States coast and geodetic survey, the weight of these blocks have been found to be approximately approxi-mately equal. This result had been suspected for decades, but Doctors Bowie and Hayford have proved It Geological science will be profoundly profound-ly changed by this discovery, for now we know the mountain masses are dua to the presence of lighter material In the earth's crust under them, and that the ocean bottoms are low because the material under them is denser or heavier than the average. Doctor Bowie concludes that there Is no tendency for the mountain masses to break down through the earth's crust, as they are not extra loads. They are like the portions of Icebergs projecting out of the water which are held up by the ice which is below or in the water. The iceberg ice-berg floats, and so does the mountain. moun-tain. Doctor Bowie, also holds that, as mountain system are in areas which were once very low in elevation, mountains moun-tains are caused by a swelling of the material in the earth's crust under them. A lessening of the density of three per cent in a column GO miles long will elevate the area about 0,000 feet. Such a change In density, due to physical or chemical changes, is within reasonable limits. Flow Is Below Crust. As the mountains, plateaus, valleys and the ocean areas are in equilibrium there must have been a transference of material from the column of the earth's crust under an area where sediments sedi-ments are deposited, hack to the area from which the material was eroded by water and wind. Doctor Bowie believes that the flow of material takes i place just below the crust, that Is j somewhat below 00 miles. The ex-' ex-' act depth at which the flow from one column to another takes place may never be discovered. Doctor Bowie states that, as material ma-terial is eroded from a mountain area, the new material pus'jed in at the bottom will tend to keep the average aver-age elevation of the mountuin system approximately constant. When material ma-terial is pushed Into the column under a mountain system to counter-balance the eroded matter, every particle of the column Is carried upward Into a colder zone. Under areas of heavy sedimentation, the material of the earth's crust is pushed down Into hotter hot-ter regions. A piece of material may thus be raised up or carried down as much as six miles and, at times, more. The great changes In tempernture are probably the cause of the uplift of a mountain system In an area of sedl- i mentation, and of the sinking of tha surface where erosion has been great. |