Editing Charles Wheatstone (section)

== Telegraph ==
Wheatstone abandoned his idea of transmitting intelligence by the mechanical vibration of rods, and took up the [[electric telegraph]]. In 1835 he lectured on the system of [[Baron Schilling]], and declared that the means were already known by which an electric telegraph could be made of great service to the world. He made experiments with a plan of his own, and not only proposed to lay an experimental line across the Thames, but to establish it on the London and Birmingham Railway. Before these plans were carried out, however, he received a visit from [[William Fothergill Cooke|William 
Cooke]] at his house in [[Conduit Street]] on 27 February 1837, which had an important influence on his future.

=== Cooperation with Cooke ===
[[File:Scientists.png|thumb|"Scientists". Photograph of (left to right): [[Michael Faraday]], [[Thomas Henry Huxley]], Charles Wheatstone, [[David Brewster]], [[John Tyndall]], published by [[Hughes & Edmonds]] in 1876]]
Cooke was an officer in the [[Madras Army]], who, being home on leave, was attending some lectures on anatomy at the [[University of Heidelberg]], where, on 6 March 1836, he witnessed a demonstration with the telegraph of professor [[Georg Wilhelm Munke|Georg Munke]], and was so impressed with its importance, that he forsook his medical studies and devoted all his efforts to the work of introducing the telegraph. He returned to London soon after, and was able to exhibit a telegraph with three needles in January 1837. Feeling his want of scientific knowledge, he consulted [[Michael Faraday]] and [[Peter Mark Roget|Peter Roget]] (then secretary of the [[Royal Society]]): Roget sent him to Wheatstone.

At a second interview, Cooke told Wheatstone of his intention to bring out a working telegraph, and explained his method. Wheatstone, according to his own statement, remarked to Cooke that the method would not act, and produced his own experimental telegraph. Finally, Cooke proposed that they should enter into a partnership, but Wheatstone was at first reluctant to comply. He was a well-known man of science, and had meant to publish his results without seeking to make capital of them. Cooke, on the other hand, declared that his sole object was to make a fortune from the scheme. In May they agreed to join their forces, Wheatstone contributing the scientific, and Cooke the administrative talent. The deed of partnership was dated 19 November 1837. A joint patent was taken out for their inventions, including the [[Cooke and Wheatstone telegraph|five-needle telegraph]] of Wheatstone,<ref>{{cite book | author = Beauchamp, Ken | title = History of Telegraphy | year = 2001 | publisher = Institution of Electrical Engineers | pages = 34–40 | url = https://books.google.com/books?id=ni7lDl3k5LwC&q=cooke+wheatstone&pg=PA30| isbn = 978-0852967928 }}</ref> and an alarm worked by a relay, in which the current, by dipping a needle into mercury, completed a local circuit, and released the detent of a clockwork.

The five-needle telegraph, which was mainly, if not entirely, due to Wheatstone, was similar to that of Schilling, and based on the principle enunciated by [[André-Marie Ampère|Ampère]] – that is to say, the current was sent into the line by completing the circuit of the battery with a make and break key, and at the other end it passed through a coil of wire surrounding a magnetic needle free to turn round its centre. According as one pole of the battery or the other was applied to the line by means of the key, the current deflected the needle to one side or the other. There were five separate circuits actuating five different needles. The latter were pivoted in rows across the middle of a dial shaped like a diamond, and having the letters of the alphabet arranged upon it in such a way that a letter was literally pointed out by the current deflecting two of the needles towards it.

=== Early installations ===
[[File:GWR Cooke and Wheatstone double needle telegraph instrument.jpg|thumb|right|A double-needle telegraph instrument of the type used on the [[Great Western Railway]]]]
An experimental line, with a sixth return wire, was run between the [[Euston railway station|Euston]] terminus and [[Camden Town]] station of the [[London and North Western Railway]] on 25 July 1837. The actual distance was only one and a half-miles (2.4&nbsp;km), but spare wire had been inserted in the circuit to increase its length. It was late in the evening before the trial took place. Cooke was in charge at Camden Town, while [[Robert Stephenson]] and other gentlemen looked on; and Wheatstone sat at his instrument in a dingy little room, lit by a tallow candle, near the booking-office at Euston. Wheatstone sent the first message, to which Cooke replied: and "never" said Wheatstone, "did I feel such a tumultuous sensation before, as when, all alone in the still room, I heard the needles click, and as I spelled the words, I felt all the magnitude of the invention pronounced to be practicable beyond cavil or dispute."

In spite of this trial, however, the directors of the railway treated the 'new-fangled' invention with indifference, and requested its removal. In July 1839, however, it was favoured by the [[Great Western Railway]], and a line erected from the [[Paddington station]] terminus to [[West Drayton railway station]], a distance of {{convert|13|mi|km|spell=in}}. Part of the wire was laid underground at first, but subsequently all of it was raised on posts along the line. Their circuit was eventually extended to {{stnlnk|Slough}} in 1841, and was publicly exhibited at Paddington as a marvel of science, which could transmit fifty signals a distance of 280,000 miles per minute (7,500&nbsp;km/s). The price of admission was a shilling (£0.05), and in 1844 one fascinated observer recorded the following:

<blockquote>
It is perfect from the terminus of the Great Western as far as'' ''Slough – that is, eighteen miles; the wires being in some places'' ''underground in tubes, and in others high up in the air, which last,'' ''he says, is by far the best plan. We asked if the weather did not'' ''affect the wires, but he said not; a violent thunderstorm might'' ''ring a bell, but no more. We were taken into a small room (we'' ''being [[Maria Kinnaird|Mrs Drummond]], Miss Philips, Harry Codrington and'' ''myself – and afterwards the Milmans and Mr Rich) where were'' ''several wooden cases containing different sorts of telegraphs. In one sort every word was spelt, and as each letter was placed in turn'' ''in a particular position, the machinery caused the electric fluid to run'' ''down the line, where it made the letter show itself at Slough, by what'' ''machinery he could not undertake to explain. After each word came a  sign from Slough, signifying "I understand", coming certainly in less  than one second from the end of the word......Another prints the messages it brings, so that if no-one attended to the bell,....the message would not be lost. This is effected by the electrical fluid causing a little hammer to strike the letter which presents itself, the letter which is raised hits some manifold writing paper (a new invention, black paper which, if pressed, leaves an indelible black mark), by which means the impression is left on white paper'' ''beneath. This was the most ingenious of all, and apparently Mr. Wheatstone's'' ''favourite; he was very good-natured in explaining but'' ''understands it so well himself that he cannot feel how little we'' ''know about it, and goes too fast for such ignorant folk to follow'' ''him in everything. Mrs Drummond told me he is wonderful for'' ''the rapidity with which he thinks and his power of invention; he'' ''invents so many things that he cannot put half his ideas into'' ''execution, but leaves them to be picked up and used by others,'' ''who get the credit of them.<ref>Sullivan, Gertrude : [https://books.google.com/books?id=YhsLAAAAYAAJ&q=A+Family+Chronicle ''A Family Chronicle''] published in 1908 (London, John Murray) by her niece, Gertrude Lyster. pp. 216–217.</ref><br />
</blockquote>

=== Public attention and success ===
The public took to the new invention after the capture of the murderer [[John Tawell]], who in 1845, had become the first person to be arrested as the result of telecommunications technology. In the same year, Wheatstone introduced two improved forms of the apparatus, namely, the 'single' and the 'double' needle instruments, in which the signals were made by the successive deflections of the needles. Of these, the single-needle instrument, requiring only one wire, is still in use.{{citation needed|date=February 2016}}

The development of the telegraph may be gathered from two facts. In 1855, the death of the [[Nicholas I of Russia|Emperor Nicholas]] at [[St. Petersburg]], about one o'clock in the afternoon, was announced in the House of Lords a few hours later. The result of [[Epsom Oaks|The Oaks]] of 1890 was received in New York fifteen seconds after the horses passed the winning-post.

=== Differences with Cooke ===
In 1841 a difference arose between Cooke and Wheatstone as to the share of each in the honour of inventing the telegraph. The question was submitted to the arbitration of the famous engineer, [[Marc Isambard Brunel]], on behalf of Cooke, and [[John Frederic Daniell|Professor Daniell]], of King's College, the inventor of the [[Daniell cell]], on the part of Wheatstone. They awarded to Cooke the credit of having introduced the telegraph as a useful undertaking which promised to be of national importance, and to Wheatstone that of having by his researches prepared the public to receive it. They concluded with the words: 'It is to the united labours of two gentlemen so well qualified for mutual assistance that we must attribute the rapid progress which this important invention has made during five years since they have been associated.' The decision, however vague, pronounces the needle telegraph a joint production. If it had mainly been invented by Wheatstone, it was chiefly introduced by Cooke. Their respective shares in the undertaking might be compared to that of an author and his publisher, but for the fact that Cooke himself had a share in the actual work of invention.

=== Further work on telegraphs ===
From 1836 to 1837 Wheatstone had thought a good deal about submarine telegraphs, and in 1840 he gave evidence before the Railway Committee of the House of Commons on the feasibility of the proposed line from [[Dover]] to [[Calais]]. He had even designed the machinery for making and laying the cable. In the autumn of 1844, with the assistance of J. D. Llewellyn, he submerged a length of insulated wire in [[Swansea Bay]], and signalled through it from a boat to the [[Mumbles Lighthouse]]. Next year he suggested the use of [[gutta-percha]] for the coating of the intended wire across the [[English Channel]].

In 1840 Wheatstone had patented an alphabetical telegraph, or, 'Wheatstone A B C instrument,' which moved with a step-by-step motion, and showed the letters of the message upon a dial. The same principle was used in his type-printing telegraph, patented in 1841. This was the first apparatus which printed a telegram in type. It was worked by two circuits, and as the type revolved a hammer, actuated by the current, pressed the required letter on the paper.

The introduction of the telegraph had so far advanced that, on 2 September 1845, the [[Electric Telegraph Company]] was registered, and Wheatstone, by his deed of partnership with Cooke, received a sum of £33,000 for the use of their joint inventions.

In 1859 Wheatstone was appointed by the Board of Trade to report on the subject of the Atlantic cables, and in 1864 he was one of the experts who advised the [[Atlantic Telegraph Company]] on the construction of the successful lines of 1865 and 1866.

In 1870 the electric telegraph lines of the United Kingdom, worked by different companies, were transferred to the Post Office, and placed under Government control.

Wheatstone further invented the [[Wheatstone system|automatic transmitter]], in which the signals of the message are first punched out on a strip of paper ([[punched tape]]), which is then passed through the sending-key, and controls the signal currents. By substituting a mechanism for the hand in sending the message, he was able to telegraph about 100 words a minute, or five times the ordinary rate. In the Postal Telegraph service this apparatus is employed for sending Press telegrams, and it has recently been so much improved, that messages are now sent from London to Bristol at a speed of 600 words a minute, and even of 400 words a minute between London and Aberdeen. On the night of 8 April 1886, when [[William Gladstone|Gladstone]] introduced his [[Government of Ireland Bill 1886|Bill for Home Rule in Ireland]], no fewer than 1,500,000 words were dispatched from the central station at [[St. Martin's-le-Grand]] by 100 Wheatstone transmitters. The plan of sending messages by a running strip of paper which actuates the key was originally patented by [[Alexander Bain (inventor)|Alexander Bain]] in 1846; but Wheatstone, aided by Augustus Stroh, an accomplished mechanician, and an able experimenter, was the first to bring the idea into successful operation. This system is often referred to as the Wheatstone Perforator<ref>{{cite web|last1=Bemer|first1=Bob|title=How ASCII Got Its Backslash|url=http://www.bobbemer.com/BACSLASH.HTM|author-link=Bob Bemer|access-date=4 August 2014|archive-url=https://web.archive.org/web/20121218064223/http://www.bobbemer.com/BACSLASH.HTM|archive-date=18 December 2012|url-status=dead}}</ref> and is the forerunner of the stock market [[ticker tape]].<ref>{{cite web|title=Kleinschmidt – Our History |url=http://www.kleinschmidt.com/Company/history.htm |access-date=4 August 2014 |url-status=dead |archive-url=https://web.archive.org/web/20140422051900/http://www.kleinschmidt.com/Company/history.htm |archive-date=22 April 2014 }}</ref>