[pas]

I think that's misleading.

There was a lot of physics already known, importance of insulation and cross-section, signal attenuation was also known.

The future Lord Kelvin conducted experiments. The two scientific advisors had a conflict. And the "CEO" went with the cheaper option.

""" Thomson believed that Whitehouse's measurements were flawed and that underground and underwater cables were not fully comparable. Thomson believed that a larger cable was needed to mitigate the retardation problem. In mid-1857, on his own initiative, he examined samples of copper core of allegedly identical specification and found variations in resistance up to a factor of two. But cable manufacture was already underway, and Whitehouse supported use of a thinner cable, so Field went with the cheaper option. """