Horizontal study of dark clouds and a reddened one at the rear in a blue sky, with two boulders or the peak of a mountain at bottom right; irregular top margin showing the gray grounding color. Date: 1860–70. Dimensions: 18.5 x 30.8 cm (7 5/16 x 12 1/8 in.). Medium: brush and oil paint on paperboard. Collection: Cooper Hewitt, Smithsonian Design Museum. Drawing, Cloud study, 1860–70 (CH 18202433)
