Michigan State University

Copper Plates in Map Production

Detail from black plate
Part of the black-ink plate to the 1912 Lansing topographic map.

From the 1880s to the 1950s, the U.S. Geological Survey used engraved copper plates in the process of printing topographic and geographic quadrangle maps. Copper alloy engraving plates were inscribed with a mirror image of the points, contour lines, symbols, and text that constitute a topographic map. Each plate was inscribed with details for a single color of ink. Every sheet of paper had to be impressed multiple times to make a complete color map. In order to make large numbers of prints, USGS transferred the image from the engraved plate to a special lithographic stone. Otherwise, the accuracy of the engraving would have been lost due to the repeated pressure required to transfer the image directly from the plate to paper. This production process not only preserved the life of each plate, but also allowed the Survey to mix and interchange other layers when needed such as surface geology, bedrock, economic geology, soils, and forestry.

Beginning February 1, 2016, the MSU Map Library is displaying all 3 copper plates used in the printing of the 1912 USGS topographic map of the Lansing area.

The blue plate is etched with water features (lakes, streams, and marshes). The most prominent feature on this plate is the Grand River running north to south. Unusually straight water lines typically indicate drains constructed by the county drain commissions.

The black plate is etched with cultural features such as roads, railroads, boundaries, and all of the text. The most prominent feature on this map is the City of Lansing.

The brown plate is etched with contour lines which communicate elevation and the shape of the land. Brown numbers are spot elevations in feet above sea level. The abnormally straight lines represent areas that were contoured, usually to make flat grades for highways and railroads.

Part of USGS topographic map of the Lansing area, 1912


The plate and map display an area that is ¼ of a degree of latitude by ¼ of a degree of longitude. The City of Lansing is located at the top, right, of the printed map, Michigan Agricultural College is just off the east edge of this map. Out in the countryside you will notice all the one-room schoolhouses situated every couple of miles. The historical topographic maps of the United States may be seen online at http://ngmdb.usgs.gov/maps/Topoview/

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