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Show CHANGES IN ROAD BUILDING NOTEWORTHY Changes in highway design due to necessity of providing adequate traffic facilities, have been as noteworthy as changes in volume and character of roadway trafffic. Greater care in finishing is noticed, and a reduction in crown until the pavement appears to be almost flat. The trend toward easy curves and grades is also very apparent. In the old days when pick and shovel were the only tools available for road building build-ing purposes, it was physically impossible impos-sible to make wide highways with low grades and easy curves. Now, however, when inventive genius has supplied us with giant tractors to furnish the motive mo-tive power for heavy grading machinery, machin-ery, the task is relatively simple and inexpensive per mile of highway. Gravel shoulders on rural highways are being made wider. The entire width of the paved surface is needed for moving traffic, and wide shoulders afford a safe place for parking and for making repairs to cars. The compacted gravel on these shoulders also makes an excellent base for a coat of a-sphallic concrete, when it is necessary to widen the paved surface sur-face of the highway. |