May 2, 1862
Photograph taken of the Topographical Engineers at Camp Winfield Scott May 2, 1862 during the Peninsular Campaign. The two men seated center and right are most likely Frederick W. Dorr and John W. Donn. The officer seated to the left is William H. Paine who invented the steel tape reel worn by the man standing on the right. Standing second from right appears to be Allan Pinkerton. The photo is one of a stereopair in the collection of the Library of Congress.