Night writing,
sonography, was a system of code that used symbols of twelve dots arranged as two columns of six dots embossed on a square of
paperboard, and is now remembered as the forerunner of
Braille. It was designed by
Charles Barbier in response to
Napoleon's demand for a
code that soldiers could use to communicate silently and without light at night. Called
sonography, each grid of dots stands for a character or
phoneme.