Chorded keyboard (a writing system for the blind) uses either 6 or 8 tactile 'points' from which all letters and numbers are formed. When Louis Braille invented it, it was produced with a needle holing successively all needed points in a cardboard sheet. In 1892, Frank Haven Hall, superintendent of the Illinois Institute for the Education of the Blind, created the Hall Braille Writer, which was like a typewriter with 6 keys, one for each dot in a braille cell. The Perkins Brailler, first manufactured in 1951, uses a 6-key chord keyboard (plus a spacebar) to produce braille output, and has been
Louis Braille for Representing by Dots the Form of Letters, Maps, Geometric Figures, Musical Symbols, etc., for Use by the Blind" was first published in 1839. Many of Braille's original printed works remain available at the Braille birthplace museum in Coupvray. "New Method for Representing by Dots..." (1839) put forth Braille's plan for a new writing system with which blind people could write letters that could be read by sighted people. Called decapoint, the system combined his method of dot-punching with a new specialized grill which Braille devised to overlay the paper. When used with an associated number table (also designed by