Congress established the United States Geological Survey (USGS) in 1879 to map the nation's mineral wealth. USGS work could not proceed without relief maps that included hydrography (streams), cultural features and topography. USGS's first maps were piecemeal work from regional geology surveys, not standardized to a specific scale or scheme. In 1882, USGS formed a geography division to systematize its cartography into a uniform format.
Powell
John Wesley Powell was the director of the USGS from 1881 to 1894. Despite losing an arm at Shiloh with the Illinois volunteers, he led parties of surveyors (map makers) in the Rocky Mountain region throughout the 1870s, including rafting the Grand Canyon. Powell's expeditions created topographic sheets that were the USGS geography division's sources for relief maps. In 1896, his 10 monographs for the National Geographic Society described the "slopes" (watersheds) of North America.
Howell
Edwin Eugene Howell worked on Rocky Mountain surveys and was with the Powell expedition through the Grand Canyon in 1874. In 1875, he made a relief map of the canyon. Afterward, Howell worked at his family's mineralogy business in Rochester, New York. He founded a mineralogy company in Washington in 1892, where his specialty was relief maps. He developed textbook standard North American relief maps that the MacMillan Company published beginning in 1900. For example, in 1904, the University of Texas Board of Regents reported obtaining copies of Howell's MacMillan Company relief maps for their geology department, including Howell's relief showing the U.S. with the curvature of the Earth.
1920 Standards
In 1920, USGS published standards for cartographic expression of relief. USGS accepted contour lines, hachuring, hill shading, stippling and brush strokes of black ink. The most enduring illustration, contours, are curving lines connecting points that have the same elevation. Hachures shadow elevation as lighted from west or northwest. Hill shading is based on how closely contours occur. Stippling is done over stencils with varying densities of holes. Brush strokes are skillfully painted over blue print impressions.
Air Photos
In the late 1930s, the United States prepared for an invasion on the Pacific Coast. For detailed relief mapping, army engineers used five-lens cameras that photographed straight down, angled forward, angled backward and angled to each side. Stereoscopic mapping of these images coordinated the photo to points of known elevations confirmed by ground surveys. They developed 3-D imaging to coordinate known points by angled projection of a blue image and a red image of the same photo onto one sheet.
Landsat
In 1965, the USGS proposed a remote sensing satellite (now LANDSAT) to confirm existing relief and landform maps and gather additional natural resource data. The military opposed civilian satellite projects, although weather satellites were orbited as early as 1960. NASA was still doing remote sensing from aircraft until the first of several USGS satellites launched in 1972. LANDSAT measures relief by bouncing radio signals onto the planet surface.
Tags: relief maps, United States, geography division, Grand Canyon, Howell worked
