 The wagon carrying Illingworth's equipment is estimated to have weighed nearly 400 lbs (c. 182 kg).Illingworth and the U.S. 7th Cavalry Regiment departed for the Black Hills on 2 July 1874 from Fort Abraham Lincoln on the west bank of the Missouri River, seven miles south of what is now Mandan, North Dakota, and returned 30 August 1874.While on the expedition, Illingworth produced about 70 glass plates – 60 of them were landscapes of the Black Hills and portraits of members of the 7th Cavalry.