Editing Charles Wheatstone (section)

=== 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:

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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>