guidon (plural guidons) 1  A small pennant or banner carried by infantry soldiers to direct troop movement. 2  A soldier assigned to carry such a banner.
Within a year or two, Western Union and other telegraph companies were using diplex telegraphs on their busiest lines in major cities. In 1874, Thomas Edison invented the first quadruplex telegraph, which was capable of sending two messages simultaneously in each direction.ears later, quadruplex telegraphs were displaced by two new inventions, multiplex telegraphy capable of eight or more simultaneous transmissions, and the use of teletype machines, which did not require their operators to know Morse Code.
The first commercial electrical telegraph, the Cooke and Wheatstone telegraph, was co-developed by William Fothergill Cooke and Charles Wheatstone. In May 1837 they patented a telegraph system which used a number of needles on a board that could be moved to point to letters of the alphabet.