Variety reports, Alistair Cooke's 15-minute film footage of Charlie Chaplin will premiere at Italy's 26th Pordenone Silent Film Festival, October 6-13th, 2007. Shot in 1933 by Cooke on Chaplin's yacht off Catalina Island, this found film was originally part of a series of star interviews created by Cooke for his student work at Yale. More at this Variety link>
Follow-up: In reading some of these later links about this re-discovered Chaplin film, they make it sound like it is a new Chaplin short, which is miss leading. Reading the Variety article, it says interviews Cooke filmed while he was a student.
With it being 1933, guessing this would have been a silent film. Portable sound cameras were later, but need to look that up again. (Most interesting for me, it was the same year The Sea Gull negatives were destroyed.)