"When the first underground and submarine telegraph cables were laid around 1850, engineers noticed that sharp signals sent in at one end emerged at the other badly blurred and appreciably delayed. This “retardation” grew worse on longer cables and threatened to make operation of the proposed 2000-mile Atlantic line unprofitably slow. Retardation presented British physicists and engineers with both an intriguing physical phenomenon and a serious practical problem, and they studied it closely from the 1850s on.

Latimer Clark, a prominent British cable engineer, brought retardation to Michael Faraday’s attention late in 1853, and Faraday’s published account of the phenomenon served to publicize both retardation and the ideas about the electromagnetic field that he invoked to explain it. Faraday’s paper led William Thomson (later Lord Kelvin) to reprint two papers on field theory he had written in the 1840s, and later in 1854 a related cable question prompted Thomson to work out what became the accepted mathematical theory of signal transmission. Moreover, it was at just this time, and largely under Thomson’s guidance, that James Clerk Maxwell first took up the study of electricity, with results that were to transform electromagnetic theory."

An agreed system of electrical units and standards was crucial to building a workable cable systemin the 1860s, as well as to advancing electrical science. Without such standards, it was almost impossible to extend accurate electrical knowledge beyond a single laboratory or testing room. Amid conflicts over competing standards and in response to rising demands from the telegraph industry, in 1861 William Thomson called on the British Association for the Advancement of Science to establish a Committee on Electrical Standards. The committee proved very influential, and its work marks one of the most important points of intersection between electrical science and technology in the mid-nineteenth century. Led by James Clerk Maxwell ,and Fleeming Jenkin, the committee determined the value of the ohm experimentally in 1862–64 and distributed standard resistance coils around the world. Standard ohms soon became a key part of quality control in the cable industry; indeed, the aim in manufacture became to make a cable that was, in effect, a chain of standard ohms strung end to end, its properties at each point known and recorded.

After the failure of the first Atlantic cable, proponents of oceanic submarine telegraphy sought to parry claims that the task they had attempted was simply impossible and to argue that it instead resulted from a series of correctable errors. Their first step was to pin as much blame as they could on Wildman Whitehouse while separating his practices from those of proper electrical scientists and engineers. The Atlantic Telegraph Company then teamed with the British government to establish a Joint Committee to investigate how such disasters might be avoided in the future. In 1861 the committee issued a massive Report that identified the rationalization of methods and standardization of materials as keys to bringing order and reliability to an industry that had hitherto lacked both. The Joint Committee Report exemplified the power of expertise backed by official authority, and it soon became the bible of British cable practice as the idiosyncratic methods of Whitehouse and other cable amateurs gave way to William Thomson and Latimer Clark’s emphasis on precise and standardized measurement. Guided by this new measurement-based approach to telegraph engineering, the Atlantic cable project was resurrected and would finally succeed in 1866.

"The first attempt to lay a transoceanic cable, the Atlantic cable project of 1856–58, had far-reaching effects on electrical theory and practice. Although it was launched by an American, Cyrus Field, the project soon came to be dominated by British capital and technical expertise. Among the leading figures in the Atlantic Telegraph Company were Charles Bright, the young chief engineer; Wildman Whitehouse, a Brighton surgeon turned electrical experimenter; and William Thomson, professor of natural philosophy at Glasgow and a member of the company’s board of directors. Whitehouse and Thomson had argued about signal propagation and cable design before joining the company; the circumstances of this dispute, and of its temporary resolution early in 1857, shed valuable light on how scientific and practical concerns interacted in the project, particularly around questions of measurement. The dispute flared again when the Atlantic cable failed in September 1858 after only a month of fitful service. The response to that failure would shape British cable telegraphy and electrical physics for decades to come."