 From these discussions, deLacy published an updated map of the Yellowstone region.When the Washburn party traveled into Yellowstone in August 1870, Henry Washburn was carrying copies of the Cook and Folsom diaries and the deLacy map.Once Folsom was back in Helena, Montana as a surveyor, his friends Nathaniel P. Langford and Samuel Thomas Hauser asked him to give a talk on the expedition to a group of prominent Helena citizens.