Piwyac, Vernal Falls, 300 feet, Yosemite. Dated: 1861. Dimensions: sheet (trimmed to image): 39.9 x 52.3 cm (15 11/16 x 20 9/16 in.) mount: 53.2 x 68.7 cm (20 15/16 x 27 1/16 in.) mat: 66 x 76.1 cm (26 x 29 15/16 in.). Medium: albumen print from coll