Washington Navy Yard, District of Columbia. Four monitors laid up in the Anacostia River, off the Washington Navy Yard, circa 1866. Ships are (from left to right): USS Mahopac, USS Saugus, USS Montauk (probably); and either USS Casco or USS Chimo. Photo mounted on a stereograph card, marked: "Photographed and published by Kilburn Brothers, Littleton, N.H.". Courtesy of Paul H. Silverstone, 1982. NHHC Photograph Collection: NH 93868.

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