Carl Wheat hypothesizes that Capt. William Ludlow (1843 - 1901), Corps of Engineers, was assigned the task of surveying the road from Carroll, Montana on the Missouri to Fort Ellis near Bozeman as a reward for good service, since it allowed him to inspect the wonders of Yellowstone without a furlough. This map was produced to accompany Ludlow's official report. In his report, Ludlow says "My own interest in this land of wonder is so keen as to lead me again to hope that it will be protected from the vandalism which it has already suffered, and that the suggestion of an accurate topographical and geological survey, to complete the work so well inaugurated by Professor Hayden, may be made the subject of favorable consideration and recommendation by the Chief of Engineers."

The map itself describes the newly opened Carroll Road. The road cut more than 200 miles from the previous route between Helena and Corinne. This resulted in a savings of about fifteen days considering the 12 or 13 miles per day the heavy bull-trains averaged. The map shows a large area from the Missouri River in the north to Helena in the west and the newly established National Park in the south. The flow of the Yellowstone, Musselshell, and Missouri Rivers are designated. It has a partial look to it; the Topographical Engineers were rigorous about showing only features they had actually surveyed. Land forms are shown with what appears to be contour lines but there is no interval stated, and Wheat calls it a pseudo-contour map. Carroll was washed away by a flood in the 1880’s and no trace of it remains today. Ironically, it is not named on the map itself.

References: Wheat (TMW) #1257.

Condition: B+

Issued folding with several minor fold separations along the sheet edges and a short binding tear at left that have all been closed on verso with archival tape. Light toning along the folds and a binding trim at left.