Oldest Picture of the Old Patent Office Building

Photo from 1846 of the Patent Office, now known as the Portrait Gallery

This 1846 picture is the oldest known photograph of the Old Patent Office in Washington, DC. It is now known as the National Portrait Gallery and Smithosonian Museum of American Art. The building was used as a hospital during the Civil War, and famously both Clara Barton (the founder of the American Red Cross) and Walt Whitman (author of Leaves of Grass, and others) volunteered there at the time.