page_title: Electrical telegraphy in the United Kingdom
section_title: Early development
hierarchical_section_title: Electrical telegraphy in the United Kingdom / Early development
caption_attribution_description: English: William Fothergill Cooke
context_page_description: Electrical telegraphy in the United Kingdom had the world's first commercial telegraph company in the nineteenth century, and British telegraphy dominated international telecommunications until well into the twentieth. Telegraphy is the sending of textual messages by human operators using symbolic codes. Electrical telegraphy sends these messages over conducting wires, often incorporating a telegram service. It is distinct from the optical telegraphy that preceded it and the radiotelegraphy that followed it. Francis Ronalds first demonstrated a working telegraph over a substantial distance in 1816, but was unable to put it into use. Starting in 1836, William Fothergill Cooke, with the scientific assistance of Charles Wheatstone, developed the Cooke and Wheatstone telegraph and Cooke formed a company to exploit it. Important components were the needle telegraph instrument suggested by Wheatstone, the battery invented by John Frederic Daniell, and the relay invented by Edward Davy.
  In 1846 the Electric Telegraph Company was formed by Cooke and financier John Lewis Ricardo.
context_section_description: The first demonstration that an electric telegraph could be operated over a substantial distance was conducted by Francis Ronalds in his Hammersmith garden in 1816.  Eight miles of iron wire were strung back and forth between wooden frames.  The source of power he used was high-voltage friction machines.  Ronalds offered his system to the Admiralty, but they were already using an optical telegraph and saw no need for Ronalds' invention, despite the optical telegraph being frequently unusable due to weather conditions.  It was never put to the test, but it is likely that Ronalds' system could not be made to work over very long distances using static electricity generators.  Even the relatively short test system only worked well in dry weather.
  Nearly all the telegraph systems that were finally successful used batteries of electrochemical cells as their source of power.  An important development that made this possible was the invention of the Daniell cell in 1836 by John Frederic Daniell.  The earlier voltaic pile suffered from falling voltage if used continuously due to the formation of hydrogen bubbles around the copper electrode which tended to insulate it.  The Daniell cell solved this problem by placing the zinc and copper electrodes in separate electrolytes with a porous barrier between them.  The hydrogen is consumed by the sulfuric acid electrolyte, oxidizing it to water, before it can reach the copper electrode in the copper sulphate electrolyte.  A later improvement by J. F. Fuller in 1853 replaced sulfuric acid with zinc sulfate.
  Another important development was the relay, invented by surgeon Edward Davy in 1837 and patented in 1838.  The relay allows weak telegraph pulses to be regenerated.  The incoming pulse activates an electromagnet which moves an armature to which are attached electrical contacts which close and complete a secondary circuit.  A local battery provides the current for a new pulse through the contacts and onwards along the telegraph line.  Davy's relay was the first device to use metallic make-and-break contacts, a great improvement on electrodes dipping into a container of mercury.  The importance of the relay lies in that it allows telegraph transmissions over long distances that would otherwise require operators at periodic intermediate stations to read and retransmit the message.  Davy began experimenting in telegraphy in 1835, and in 1837 demonstrated his telegraph system in Regent's Park over a mile of copper wire.  He held an exhibition in London, but after his marriage broke down he abandoned telegraphy and emigrated to Australia.
  The person who was the driving force in establishing the telegraph as a business in the United Kingdom was William Fothergill Cooke.  He was initially inspired to build a telegraph after seeing a demonstration of a needle telegraph by Georg Wilhelm Muncke in March 1836.  He built a prototype shortly afterwards, but did not pursue this design.  Instead, he looked for mechanical solutions because he believed (wrongly) that the needle telegraph would require multiple wires, each driving a separate needle.  Cooke initially made a telegraph with a clockwork detent mechanism operating electromagnets.  The first mechanical apparatus was built in 1836.  He pitched the telegraph to various railway companies as a means of signalling to control trains but without success.  Cooke, who was not scientifically trained, sought advice from Michael Faraday and Charles Wheatstone.  Wheatstone recommended using a needle telegraph system.  After the collaboration with Wheatstone began, only needle telegraphs were pursued.  The Cooke and Wheatstone telegraph developed by the two men and patented in May 1837 could have various arrangements of needles, but the one that initially became successful used five needles.  They were operated in pairs so that the pair of needles pointed to a letter of the alphabet marked on a board.
  Cooke proposed the Cooke and Wheatstone system to the Liverpool and Manchester Railway, and a four-needle system was trialled by the London and Birmingham Ra
caption: William Fothergill Cooke
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