Electrical telegraphs were point-to-point text messaging systems, primarily used from the 1840s until the late 20th century.
It was the first electrical
telecommunications system and the most widely used of a number of early messaging systems called telegraphs, that were devised to communicate text messages quicker than physical transportation.
From early studies of electricity, electrical phenomena were known to travel with great speed, and many experimenters worked on the application of electricity to communications at a distance. All the known effects of electricity—such as sparks, electrostatic attraction, chemical changes, electric shocks, and later electromagnetism—were applied to the problems of detecting controlled transmissions of electricity at various distances.

In 1753, an anonymous writer in the Scots Magazine suggested an electrostatic telegraph. Using one wire for each letter of the alphabet, a message could be transmitted by connecting the wire terminals in turn to an electrostatic machine, and observing the deflection of pith balls at the far end.[11] The writer has never been positively identified, but the letter was signed C.M. and posted from Renfrew leading to a Charles Marshall of Renfrew being suggested.[12] Telegraphs employing electrostatic attraction were the basis of early experiments in electrical telegraphy in Europe, but were abandoned as being impractical and were never developed into a useful communication system.[13]
In 1774, Georges-Louis Le Sage realised an early electric telegraph. The telegraph had a separate wire for each of the 26 letters of the alphabet and its range was only between two rooms of his home.[14]

In 1800, Alessandro Volta invented the voltaic pile, providing a continuous current of electricity for experimentation. This became a source of a low-voltage current that could be used to produce more distinct effects, and which was far less limited than the momentary discharge of an electrostatic machine, which with Leyden jars were the only previously known man-made sources of electricity.
Another very early experiment in electrical telegraphy was an “electrochemical telegraph” created by the German physician, anatomist and inventor Samuel Thomas von Sömmering in 1809, based on an earlier 1804 design by Spanish polymath and scientist Francisco Salva Campillo.[15] Both their designs employed multiple wires (up to 35) to represent almost all Latin letters and numerals. Thus, messages could be conveyed electrically up to a few kilometers (in von Sömmering’s design), with each of the telegraph receiver’s wires immersed in a separate glass tube of acid. An electric current was sequentially applied by the sender through the various wires representing each letter of a message; at the recipient’s end, the currents electrolysed the acid in the tubes in sequence, releasing streams of hydrogen bubbles next to each associated letter or numeral. The telegraph receiver’s operator would watch the bubbles and could then record the transmitted message.[15] This is in contrast to later telegraphs that used a single wire (with ground return).