Long-distance writing

Dot, dash, dot ...

Man's first attempts to send signals by electricity date back to the 18th century. Many scientists worked on the problem, but none of them was able to set up a really good system. Finally, in 1837, an American named Samuel F. B. Morse patented the first practical telegraph.
In one type of telegraph, a key is pressed briefly for a dot and longer for a dash. Pressing down allows electric current to flow through wires to a receiver. There the current enters an electromagnet-a coil of wire around an iron core. When current flows in this device it becomes a magnet and attracts a movable bar. The bar clocks out the dots and dashes.
Morse also invented the alphabet code of dots and dashes that was named for him and is still in use today.
The first telegraph message was sent from Washington, D.C., to Baltimore, Maryland, in 1844. It said"What hath god wrought!"Communications have improved greatly since then, in 1963 President John F. Kennedy took part in the first conversation by satellite between the USA and Africa.