View of a Pontoon Bridge Built by the 50th New York Engineer Regiment Over the Pamunkey River at Nelson's Crossing, Virginia (1864)

View of a pontoon bridge built by the 50th New York Engineer Regiment over the Pamunkey River at Nelson's Crossing, Virginia, May 1864. The head of an unidentified man is visible in the foreground. By Timothy O'Sullivan. Animated stereoscopic photographs.

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