GIS project will digitize 80,000 maps in 5 years

The Library of Congress has launched one of the government's most ambitious geographic information system (GIS) projects to date, with plans to digitize and place on-line as many as 80,000 maps within the next five years.

At the end of the project, a 20-terabyte database of historic American and European maps will be available to researchers over the Internet. But Gary Fitzpatrick, a GIS specialist with the library, said the agency hopes to continue to use imaging and GIS technology to scan and disseminate additional maps owned by LOC and other organizations.

Louis Hecht, a private GIS consultant, said that while most federal agencies want to build electronic catalogs of geographic data, "there's been a lot of talk but no action."

For example, another large GIS digital library project, sponsored by the National Science Foundation, NASA and the Defense Advanced Research Projects Agency, called the Alexandria Digital Library, is still in its research phase. "This is a very high-visibility project," Hecht said. "This is a place where the technology that has been developed over the past couple of years can be applied in a way that benefits the public and prove to potential users that it works."

Most of the equipment, software and systems development support has been donated by 18 vendors who view the project as a way to test new applications. Hewlett-Packard Co. has provided more than $600,000 worth of equipment for the program, including a server, a plotter, 51/4-inch optical jukeboxes, Unix workstations, PCs, printers and software.

Ralph Ehrenberg, chief of LOC's Map and Geographic Division, said the gift "is laying the foundation for a state-of-the-art GIS facility." HP plans to upgrade the equipment as new technology becomes available.

Fitzpatrick said one of the main technical challenges of the project is to figure out a way to transmit the scanned images of the maps over the Internet. Many files, he said, "will end up being in the gigabyte size." The public will be able to view the on-line maps at workstations in the LOC reading room, order electronic copies and print them on-site.

Corporate sponsors of the new Center for Geographic Information will help LOC make such technical decisions as "what file formats we're going to save things in, what compression techniques we're going to use, and color- and density-resolution issues."

In addition, he said, the library is researching how to use "electronic watermarks" to protect against forgeries of digital copies.

Initially, LOC will digitize maps in its "core" historical Americana collections and also put on-line a series of topographical maps of Europe that are used frequently by genealogists.

Hecht said the project could create a host of new GIS applications. Among them, he said, are tools to study how maps have been produced, how cartographers created more accurate maps over time and the different perspective map makers took of their subjects.

"It provides [users] with a very unique opportunity to use these digitized maps as a way of researching and understanding the way to think spatially," he said.

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- Anne Armstrong contributed to this report.