Horsedrawn equipment making a cut and raising levee across Souwashy Creek Bottom near Meridian, Miss.
Except where the terrain was flat, the rolling profile and widening alinement of the wagon road era continued. Although location and design engineers recognized the desirability of gentle curvature and uniform grades, much of the design was dictated by economics and the limitations of grading equipment. Grading was performed largely with animal-drawn equipment; hence heavy cuts and fills and direct alinement were avoided in favor of sidehill locations. Power shovels were in common use for rock excavation and sidehill casting, but the narrow cuts and fills of the period were too confining for efficient use of motorized hauling units, which were also poorly adapted to operating on newly placed embankments. For the year 1920, Minnesota reported that equipment actually engaged in highway construction included 2,693 scrapers (wheel, slip, or Fresno), 36 steam shovels and 6,212 horses and mules, together with 466 motor trucks recently acquired as war surplus materials.[1] In Illinois in 1924, a recordbreaking year for construction in that State, 11,700 men and 3,000 teams were employed, a “team” consisting of two or more animals. The day of mechanization was still in the future.
Roadbuilders then, as always, were realists. They were in a race with time to pave as many miles as possible with available funds. Office seekers made extravagant promises for getting the voters out of the mud. The report of one highway department in 1924 boasts that of the 4,671 miles of hard surfaced roads then existent in the State, 75 percent were completed during the 4-year tenure of the encumbent governor.[2] One result of this frenzied effort to add miles of pavement was that many design features, later found to be hazardous, were incorporated into the highway system before a background of experience could be developed.
Every section of newly paved highway seemed to have its “deadman’s curve.” Vehicular brakes were generally poor, as was lighting equipment. Many trucks using the highways in the late twenties were still equipped with acetylene or kerosene lamps, and their speeds were limited by mechanical engine governors to 15 to 18 m.p.h. A good number of horsedrawn vehicles continued to use the public highways. Passenger car speeds increased rapidly in keeping with highway and automotive improvements. In 1920 most States had a 25 m.p.h. speed limit for rural highways. By 1930 the speed limit most frequently
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