Rock Plaster Manufacturing Co. steamboat ROBERT L. STEVENS sunk at dock, circa 1923 gelatin silver print Merritt-Chapman & Scott Corporation circa 1923 2008.28.5.387 ViewRock Plaster Manufacturing Co. steamboat ROBERT L. STEVENS sunk at dock, circa 1923 gelatin silver print Merritt-Chapman & Scott Corporation circa 1923 2008.28.5.388 View