The United States Patent Office Building in Washington, D.C., identified by ink inscription along the left border of the mount, is documented in this CDV dating to the 1860s, with no photographer's imprint visible. The wide-angle view captures the full neoclassical facade of one of the most admired public buildings in the capital, photographed from across an unpaved street that shows evidence of recent construction or grading work in the foreground

The building presents its full length in a three-quarter view, showing the two projecting pedimented porticos with tall Greek Revival colonnades at either end connected by a long central block with regularly spaced windows across two full stories. An iron fence runs along the street frontage, several figures are faintly visible near the entrance, and a church steeple and residential buildings are visible at far right. A telegraph or signal pole stands prominently at center.

The Patent Office Building, now the home of the Smithsonian American Art Museum and the National Portrait Gallery, was constructed between 1836 and 1868 and was considered one of the finest examples of Greek Revival civic architecture in the United States. During the Civil War it served as a hospital and barracks, and President Lincoln's second inaugural ball was held there in March 1865.