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Old maps, new mission

By Nancy Rapavi, Office of Corporate Communications
Pathfinder Magazine
Dec. 2, 2014

The basement aisles of America's oldest federal cultural institution run long and cool.

Maintained at a constant 65- 69 degrees to protect decades-old delicate maps and documents, one of the most comprehensive cartographic collections in the world is tucked away in forest green filing cabinets in the basement of the Library of Congress in Washington, D.C.

Soon more than 30,000 of these maps will be digitally available to intelligence analysts and the public thanks to a five-year partnership between the National Geospatial-Intelligence Agency and the library.

The collaboration entails NGA scanning maps from the library’s Africa collection. Members of the NGA GEOINT Research Center then add metadata, including map sheet names and coordinates, before transferring the data electronically to NGA. The library will maintain this data for the public, and NGA analysts will have access to the historical maps.

“It’s a win-win. The Library of Congress gets the scans of the maps in their collection, and NGA gets the images and information for maps [it doesn’t] have,” said Paulette Hasier, head librarian at NGA’s GEOINT Research Center at the agency’s Springfield, Virginia, headquarters.

The Library of Congress has been a research mecca for Congress and the public since its inception in the 1800s and now hosts more than 5.5 million maps. About 30,000 maps in the library’s collection will be scanned and outfitted with metadata, said Craig Simon, NGA’s manager for the project.

“We are adding maps to areas where we have gaps in our collection, said Simon. “This project will really help us build our collection.”

Derived from numerous sources, the maps feature hundreds of languages and dialects, which hint to the politics and history when the maps were created.

For example, one map set in the collection includes Egyptian cadastral maps, or maps that show ownership boundaries, from the 1920s to 1940s. Borders vary based on what country created the map.

Historical maps allow us to determine who was there and why they were interested in the area, said Danielle Mackin, an NGA employee who works full time from the library with the metadata tagging team.

Due to their age, historical maps also have a tendency to fade and rip. Because of their fragility and susceptibility to damage, older and more delicate maps are scanned on large flatbed scanners. An upright scanner is used for more modern maps.

Once scanned, NGA researchers electronically add metadata.

“Meta-tagged information adds layers of granularity to the historical maps,” said Simon.

Details include the producers of the map, the area of the world depicted, its title, the year it was completed and its edition.

“We want to incorporate metadata so that the maps are findable, readable and researchable,” said Simon. “If it’s not findable, it’s not helpful.”

NGA’s partnership allows the library to achieve a higher level of detail and exposure that could not be achieved alone, said Colleen Cahill, the digital conversion coordinator for the Library of Congress and NGA’s liaison with the library. The library doesn’t have the staff or scanners it requires to complete the work.

Photo: Danielle Mackin and Craig Simon work with the Library of Congress to catalog historical maps of Africa with metadata. Photo by Kevin Clark, Office of Corporate Communications