In 1930 the United States Department of the Interior held a conference in Browning, Montana for plains Indians to display their sign language so that it could be filmed for posterity. The conference was organized by General Hugh Lenox Scott at a cost of $5000 and is an ambitious example of salvage ethnography--the attempt to record the culture of a people thought to be on the verge of extinction.
This fascination collection of film from the conference was placed on YouTube by Tommy Foley, "I have translated the direct literal meaning of the signs in this film to English. Though I have added a little more than the literal meaning in some cases when more was meant by the signer using space, position, combination of signs," writes Foley. The description also contains a link to his website, which is an intriguingly designed site but does not seem to contain any additional information. According to the short descriptions on YouTube accompanying some of the videos, General Scott filmed 300 signs, the start of a project that was to have reached 1300 signs but was never completed.
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Scott was one of those nineteenth-century officers who took great interest in American Indians. Though I am usually skeptical when such men are referred to as "experts," in Scott's case it may have been true. Scott's papers at the Library of Congress contain many stories he collected from the Kiowa, for example. Google Books has his autobiography--but since it was published in 1928 we only get the snippet view. A year earlier and we would have the whole thing!