April 25, 1861

Boschke. Map of Washington City, seat of the federal government, 1857

Boschke. Topographical map of the District of Columbia, 1861
With the outbreak of hostilities in April 1861, it became necessary to begin preparing the defenses of Washington, DC. In 1857, Albert Boschke, a German born civil engineer, published his Map of Washington City, District of Columbia, seat of the federal government: respectfully dedicated to the Senate and the House of Representatives of the United States of North America which showed, for the first time, the location of every structure in the city as of the publication date.
Following the publication of the 1857 map, Boschke and his surveyors continued surveying the entire District of Columbia, sometimes referred to as the ‘ten mile square’, which resulted in his landmark Topographical map of the District of Columbia / surveyed in the years 1856 '57 '58 & '59. Published in 1861, near the outbreak of the war, this very detailed map showing the locations of all the structures in the city was a potential threat to the security of the entire city, the seat of the federal government.
According to an 1894 article by Marcus Baker in the National Geographic Magazine, Boschke sold his interest in the map to the publisher, David McClelland. Shortly after publication, representatives from the War Department seized the original manuscript and copper plates from which the map was published to prevent dissemination of the map.
Map Citations
Boschke, Albert. Map of Washington City, District of Columbia, seat of the federal government: respectfully dedicated to the Senate and the House of Representatives of the United States of North America / surveyed and published by A. Boschke C.E. [Washington] : A. Boschke, 1857 (N[ew] Y[ork] : Lith. of J. Bien). 1 map : hand col. ; 131 x 126 cm.
Catalog record: http://lccn.loc.gov/88694030
Boschke, Albert. Topographical map of the District of Columbia / surveyed in the years 1856 '57 '58 & '59 by A. Boschke ; engraved by D. McClelland, Washington, D.C. Washington : D. McClelland, Blanchard & Mohun, 1861. 1 map ; 99 x 103 cm
Catalog record: http://lccn.loc.gov/88694013
References
Baker, Marcus. "Surveys and Maps of the District of Columbia," National Geographic Magazine (vol. 6, November 1, 1894), pp. 149 – 178.
Catalog record: http://lccn.loc.gov/14007038