This episode originally aired in June of 2015.
From the original show notes:
“This week on The History Files, we tackle the phenomenon that is the Westward Expansion movement of the late 18th to mid 19th century in North America. Disclaimer: nobody dies of dysentery in this episode.”
Links:
Artist’s impression of the incident with Arnold holding a sketch of the object (ufoinsight.com) Long rifle (en.wikipedia.org)
The Sharpened Axe: The Development of the American Felling Axe in Northern Maine, by Chingatchgook
Two Years Before the Mast, by Richard Henry Dana, Jr.
The Project Gutenberg eBook of The Prairie Traveler, by Randolph B. Marcy
The Prairie Traveler: A Hand-Book for Overland Expeditions, by Randolph Marcy (full text)
The History Files Archives: ep 019