In 1818, a year after the death of Scottish American physician and scientist, William Charles Wells, his Two Essays: One upon Single Vision with Two Eyes; the Other on Dew. A Letter to the Right Hon. Lloyd, Lord Kenyon and an Account of a Female of the White Race of Mankind, Part of whose Skin Resembles that of a Negro was published in London. Wells’s “Account of a female of the white race. . . ." was read before the Royal Society in 1813, but first appeared in print posthumously. It contained the first recognizable statement of the principle of natural selection. In his study of an albino negro woman, Wells assumed a biological evolution of the human species, drawing an analogy between man’s selective breeding of domestic animal varieties and nature’s selection of varieties of men best suited to various climates. He wrote,
"[What was done for animals artificially] seems to be done with equal efficiency, though more slowly, by nature, in the formation of varieties of mankind, fitted for the country which they inhabit. Of the accidental varieties of man, which would occur among the first scattered inhabitants, some one would be better fitted than the others to bear the diseases of the country. This race would multiply while the others would decrease, and as the darkest would be the best fitted for the [African] climate, at length [they would] become the most prevalent, if not the only race."
Neither Charles Darwin nor Alfred Russel Wallace was familiar with Wells’s paper when they formulated the theory of natural selection, but after Darwin published the Origin in 1859 Wells' paper was called to his attention, and Darwin paid tribute to Wells’s pioneering statement in the historical introduction to the third edition of the Origin. Wells’s paper was contained in the first collected edition of his essays on binocular vision and on dew formation, both of which represented advances in the knowledge of these subjects.
Hook & Norman, The Haskell F. Norman Library of Science and Medicine (1991) no. 2200.