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E.G. Arnold’s most famous work doesn’t have the catchiest title. But it sure made a splash when it first went on sale.

The land surveyor’s “Topographical Map of the Original District of Columbia and Environs: Showing the Fortifications around the City of Washington” was available in local shops for only two days—in 1862. Then the U.S. War Department swooped in, not only confiscating unsold copies but retrieving copies from purchasers’ homes and seizing the copper plate from which the map had been printed. Concerned that the map would reach the hands of the Confederacy’s leadership, the department destroyed the items.

Arnold’s map had seemingly been doomed by its creator’s dubious timing and startling lack of forethought. He published it not long after the start of the Civil War—and within a year of the confiscation of another District map. It was also produced without the Union Army’s knowledge or consent, and was sold within the District, where a large percentage of residents sympathized with the Confederacy. And the map delivered exactly what its title promised: the topographical features of the area around the District, the locations of the 51 Union Army forts that then defended the city, and the major surrounding roads, rivers, railroads, and waterways. An accompanying chart detailed population according to race.

But despite the War Department’s attempt to eradicate the map, a few copies survived, although no one can say exactly how many remain. (One historian guesses fewer than 15.) And no one knows how the copies survived from 1862 to today. According to Joyce McMullin, branch manager of special collections for the Alexandria Library, the copy of the Arnold map that hangs in the Special Collections room there has simply “always been here” for the past 30-plus years.

The map, approximately 30 inches by 33 inches, hangs in a simple black frame in a high-profile area just above a photocopier. Brittle and faded, it’s still an eye-catcher. “Everybody who comes in photocopies something….This is a genealogy library,” McMullin says. “People look at the map and say, ‘Oh, gee, nice map. Can I buy one?’”

Until recently, the answer was no. But when it became obvious that the Arnold map might be a popular item, the library had it replicated; prints have been on sale since early November, with proceeds earmarked to help the library purchase additional historical and genealogical resources.

The reprinted version of the map is slightly smaller than the original and features deeper colors, such as a parchment-yellow background, red dots marking the locations of the 51 forts, and pastels highlighting the downtown area. The reprint also features the folds and wear marks that are unique to the library’s original. “We were striving for a beautiful display piece,” says McMullin, “and I think we got one.”

According to author and local historian David Goode, the map is an eloquent piece of history.

“The Civil War is the most important thing that ever happened in Washington,” says Goode. “The map is wonderful because it shows the Union’s anxiety [about] losing the city to Confederate troops, which was really unfounded because Washington was so well-protected.”

So was the War Department’s destruction of the map necessary?

“Frankly, I don’t think it made any difference,” says Goode. “After [losing] the Battle of Manassas in 1861, the Union was hypersensitive about anything that could get to the Confederates.” The Union Army “soon had [approximately] 20,000 troops manning [what came to be] the 68 forts around the city. All the forts were connected by trenches or roads, so that if one was attacked, the troops could be rushed in from other forts through these trenches. It was beautifully designed—the most fortified city in the world.” —Matthew Summers