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Show NON-JARRING HIGHWAY SURFACES SUR-FACES In the old days of railroading it was a common accident for a locomotive loco-motive wheel to snap off from what was called crystallized axle. The forever humping over the rail joints of imperfect tracks was the cause of many a train wreck and loss of thousands of lives. The same effect is produced on motor vehicles by the continuous jar when speeding over a concrete surfaced sur-faced highway witli minute roughness. rough-ness. Automobiles and trucks crystallize the finest steel from vibrations caused by going at high speed over an imperfect surfaced road. Not only will the best steel crystallize crys-tallize at the point of shock, but the concrete itself will crumble from the impact on a rigid gratuitous surface. California has laid 3,0-00 miles of rigid surface concrete roads, but 30 percent of this mileage is shattered, and 1500 miles will be resurfaced. In two years 5U0 miles have been resurfaced with a bituminous shock-absorbing shock-absorbing cushion and other states are requiring shock absorhers. The fatigue of a raw concrete surface, sur-face, the wear and tear on tires, the final crystallization of structure of both steel and concrete, are facts of such common everyday observation that ordinary intelligence ought to demand the non-jarring surface in highway construction |