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
Typhoon Dot (1985) suit 12 hours later. Due to the impending threat of Dot, storm signals were raised along the north and central Philippines. The metropolis of Manila was placed on typhoon alert, forcing the mobilization of emergency crews. Seven domestic and two military flights were called off. Additionally, railway and shipping services were cancelled. All United States military installations in the Philippines were placed in a Tropical Cyclone Condition of Readiness and two airbases, Clark Air Base and Cubi Point NAS, were evacuated. Schools and many offices were shut down in preparation of Dot. Typhoon Dot was the strongest tropical cyclone to