Photograph of unidentified men mounted on three of William E. Boeing's racehorses, circa 1940s. The horses are identified in the inscription as Pony, Slide Rule, and Devil's Thumb.Inscription on verso: "Pony, Slide Rule, Devil's Thumb."
Letterpress print of Jean-Pierre Blanchard and Dr. John Jefferies departing Dover during their 1785 balloon flight over the English Channel, art by E. W. Cocks, circa 1840.