Richard Conniff brings us the rather incredible story of Paul du Chaillu, Western explorer, and, evidently, a black man in passing. After bringing home specimens of the gorilla, and (perhaps unwittingly) fueling the typical speculations of blacks and Irish as direct descendants, du Chaillu finds himself under the microscope:

[T]he truth seems to be that his mother was a woman of mixed race, possibly a slave, on the Indian Ocean island of Réunion, where his father had been a merchant and slaveholder. Concealing this background, the historian Henry H. Bucher Jr. has written, was "an understandable choice during the heyday of scientific racism." In fact, Du Chaillu's expedition to Gabon had been sponsored by the Academy of Natural Sciences in Philadelphia, then the center of scientific racism. (Samuel G. Morton kept a vast collection of skulls there, "the American Golgotha," for the purpose of racial comparisons.) The "mysterious and rapid" end to Du Chaillu's close association with the Academy in 1860 may have resulted, says Bucher, from "a committee member's discovery of his maternal ancestry."

A letter sent to an English friend in the thick of the Du Chaillu controversy supports this theory. George Ord, an officer of the academy, wrote that some of his learned colleagues had taken note when Du Chaillu was in Philadelphia of "the conformation of his head, and his features" and detected "evidence of a spurious origin." Ord added: "If it be a fact that he is a mongrel, or a mustee, as the mixed races are termed in the West Indies, then we may account for his wondrous narratives; for I have observed that it is a characteristic of the negro race, and their admixtures, to be affected to habits of romance."

We've talked a lot about the role religion played in 19th century racism. In fact white supremacy was not seen simply as the righteous execution of God's plan, but the sound, sober verdict of logic and science. We laugh today at drawing conclusions from "the conformation" of someone's skull. But in the 19th century, it was believed by very learned people that phenotype held incredible -- but reasonable -- predictive powers.

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