Oldest Native Indian Footage - Oglala Lakota Chief Iron Tail and William F Cody - Buffalo Bill

I've been asked by many people what the date of this is, so I thought I'd post what I know here. I'm not sure of the exact date, but you can put it in a certain time frame. The earliest known silent film was in 1888, and Iron Tail died in 1916 where as Buffalo Bill died in 1917. For those of you who dont know, Chief Iron Tail is the Oglala Lakota Chief depicted on the U.S nickel from 1913 to 1938. More interesting is the fact that while its a silent film they are using 'plains sign language' to communicate - which its meaning is now possibly lost to antiquity after being in use for centuries if not even longer.