Artists were assigned to many different types of explorations. John Mix Stanley, a painter, traveled with the United States Army during the U.S.-Mexican War in 1846 and recorded the landscape as the Army marched from New Mexico to California.

Scientists also accompanied the Army to study the land and to help make an inventory of the territory. The written report used Stanley's paintings as illustrations. (Casa Grande Ruin is now also a national park.)

Stanley also served as artist for a team surveying a possible railroad route extending across North America.

Illustration: John Mix Stanley, Casa Grande Ruin, 1846, oil on board, Buffalo Bill Historical Center, Cody, Wyoming. Gift of George M. Stanley (grandson of the artist) and Family, 1.99.