“I have also cleared the electromagnetic theory of light from all unwarrantable assumption, so that we may safely determine the velocity of light by measuring the attraction between bodies kept at a given difference of potential, the value of which is known in electromagnetic measure.”

—  James Clerk Maxwell

Letter to C. Hockin, Esq. (Sept 7, 1864) as quoted by Lewis Campbell, William Garnett, The Life of James Clerk Maxwell: With Selections from His Correspondence and Occasional Writings https://books.google.com/books?id=B7gEAAAAYAAJ (1884)

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Scottish physicist 1831–1879

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