It wasn't until he was at the New York Institute for the Blind that a teacher realized what was happening and taught him manual sign language, where word symbol

It wasn't until he was at the New York Institute for the Blind that a teacher realized what was happening and taught him manual sign language, where word symbols are formed by the questioner's fingers pressed against the palm of the blind person's hand. You can see an example of this in the movie about Helen Keller called The Miracle Worker. This is my favorite scene -- where Helen finally understands. It always makes me cry. https://www.youtube.com/watch?v=QlKuJBiw1ac https://www.youtube.com/watch?v=QlKuJBiw1ac