In its eagerness to push toward Utah in its race with the Westward-building Union Pacific, the Central Pacific bridged many of the High Sierra chasms with timber trestles. When the railroad was completed, they back and the Chinese laborers that built the railroad filled them in with solid earth and embankments. This photo was taken at Secrettown Trestle, 62 miles from Sacramento on the western slope of the Sierra in 1877. Scrapers were not in use yet for grading. Dynamite had been invented but was not in general use. The workers used picks and shovels, chisels and hammers, black powder, wheelbarrows and one-horse dump carts.