Dactylology (?), n. [Gr. daktylos finger + -logy.] The art of communicating ideas by certain movements and positions of the fingers; -- a method of conversing practiced by the deaf and dumb.[1913 Webster]
&hand_; There are two different manual alphabets, the one-hand alphabet (which was perfected by Abbé de l'Epée, who died in 1789), and the two-hand alphabet. The latter was probably based on the manual alphabet published by George Dalgarus of Aberdeen, in 1680. See Illustration in Appendix.[1913 Webster]