Lewis and Clark had a secret weapon when they went on their famous exploration of what is now known as the Western United States. The weapon was a late 18th Century .46 cal. 20 shot repeating air rifle by Girandoni. I had never heard of this rifle but apparently it was also used during the Napoleonic Wars. After watching this I did read Undaunted Courage by Stephen Ambrose, the book that is mentioned in the video.