Telegraph code and sentence gaps should be 5 or 7 dots long (change from earlier standard – 5 dots). The speed of sending is also referred to as words per minute, and is classically based on the 'paris' formula - as 'paris' is considered to be an average length word. See main article on Morse Code. Morse code can even be used to transmit Chinese characters. There already existed dictionaries which numbered the Chinese characters. It is simply a case of sending the numbers by Morse Code, and these numbers are then looked up in the dictionary at the receiving end. In
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