On this day in Lewis & Clark history...
After waiting for the Missouri River fog to lift near present Nemaha, Nebraska, the Expedition sets out at 7 am. Lewis' chronometer, necessary for calculating accurate longitude, stops running.
From the journals...
July 15th, Sunday
this plain appeared to extend 20 or 30 miles, those Hills have but little timber, and the Plain appears to Continu back of them—
Kansas buffalo wallow
Photo by an unknown photographer: Plate 2 in U.S. Geological Survey. Folio 212. 1920.