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Description: | Cooke and Wheatstone's four needle telegraph, 1838. It is a modified form of the five-needle instrument. To signal some letters two needles are deflected. The keyboard has 10 keys and the line has four wires. An operator can send or receive messages up or down the line by using the change over switch on the right hand side. It disconnects the line in one direction so he can communicate in the other direction. It was possibly used experimentally by the Great Western Railway on the Paddington to West Drayton line or in 1840 on the Blackwall Railway at an intermediate station.
William Fothergill Cooke (1806-1879) and Charles Wheatstone (1802-1875) were granted a patent for five- and four-needle telegraphs in 1837 (number 7,390) but the ability to operate in either direction was described in Cooke's patent of 1838 (number 7,614). | License: | http://creativecommons.org/licenses/by-nc-sa/2.5/ | Subjects: | four needle telegraph | Temporal: | 1838 | Source: | Science Museum | Creator: | Cooke, Sir William Fothergill | Identifier: | 1876-1274 | Go to resource |
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