Braille typewriter. Old typewriter with a braille keyboard. The sliding pointer (bottom right) would be adjusted to select the desired letter, number, or punctuation mark. The raised braille dots would enable a blind person to identify the character selected. The trigger keys (left) print the letter selected, on paper (not shown) wrapped around the cylindrical roll (across top). This moves past the printing point during typing, and triggers one of the bells (centre) to signal the end of a line. At this point, the roll is pushed back for the start of a new line. Braille was invented by Louis Braille (1809-1852). The first typewriters were produced in the 1870s.