Highway bridges and culverts
A 1912 U.S. Department of Agriculture Office of Public Roads bulletin by Charles Hamilton Hoyt, with William H. Burr, issued in Washington to instruct county officials and rural engineers in building highway bridges and culverts. Halftone photographs show covered timber spans, steel truss bridges and stone abutments in bare winter landscapes, paired with line-drawn cross-sections of box culverts whose stippled earth, hatched backfill and labels like "steel rods" give usable engineering-diagram textures.
