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 and most versatile methods of telecommunication. The most common distress signal is SOS – three dots, three dashes, and three dots – internationally recognized by treaty. Beginning in 1836, the American artist Samuel F. B. Morse, the American physicist Joseph Henry, and Alfred Vail developed an electrical telegraph system. This system sent pulses of electric current along wires which controlled an electromagnet that was located at the receiving end of the telegraph system. A code was needed to transmit natural language using only these pulses, and the silence between them. Around 1837, Morse, therefore, developed an early forerunner to the