Braille pattern dots-15 Braille pattern dots-15 The Braille pattern dots-15 ( ) is a 6-dot braille cell with the top left and middle right dots raised, or an 8-dot braille cell with the top left and right upper-middle dots raised. It is represented by the Unicode code point U+2811, and in Braille ASCII with E. In unified international braille, the braille pattern dots-15 is used to represent unrounded, near-mid, front vowels, such as /e/ or /ɛ/. It is also used for the number 5. Related to Braille pattern dots-15 are Braille patterns 157, 158, and 1578, which are used in 8-dot braille systems,
Morse code which became known as "Hamburg alphabet" by Friedrich Clemens Gerke in 1848. It was adopted by the Deutsch-Österreichischer Telegraphenverein (German-Austrian Telegraph Society) in 1851. This finally led to the International Morse code in 1865. In the 1890s, Morse code began to be used extensively for early radio communication, before it was possible to transmit voice. In the late 19th and early 20th centuries, most high-speed international communication used Morse code on telegraph lines, undersea cables and radio circuits. In aviation, Morse code in radio systems started to be used on a regular basis in the 1920s. Although previous transmitters were