Platt D. Babbitt, ‘Niagara Falls’, ca. 1860, National Gallery of Art, Washington, D.C.
image: 16.5 x 21.6 cm (6 1/2 x 8 1/2 in.)  case: 18 x 23 x 2 cm (7 1/16 x 9 1/16 x 13/16 in.)