The Pest(1922)

Stan is Jimmy Smith, a salesman who is trying hard to pitch his Napoleon book to an uninterested customer as they stand in front of some iron gates. When an elderly gentleman approaches the two men he uses sign language to communicate to the 'customer' and they leave together. This is when Stan sees the sign for the Deaf & Dumb Institute that his subject was standing in front of. An elderly lady then walks out of the gates and Stan uses sign language in an attempt to talk to her. Of course, she is not deaf or dumb and gives him some verbal abuse for assuming so.