Color film in the 1950s barely registered dark skin tones; Kodak had developed the product to measure images against the white skin of a model known as Shirley. The company eventually modified its film emulsion, responding to complaints from advertisers promoting wood furniture and chocolate.

In the 1860s, toward the end of his life, “father of computing” Charles Babbage “never abstained from the publication of his sentiments when he thought that his silence might imply his approbation,” wrote his friend Harry Buxton, “nor did he ever take refuge in silence when he believed it might be interpreted as cowardice.”

A scholar in Peking contracted malaria in 1899 and was given medication with an ingredient labeled “dragon bones.” The bone chips, he found, were inscribed with writing dating back to China’s second dynasty. Thousands more were uncovered in the decades following; many of these “oracle bones” had inscriptions recording celestial events, which scientists have since used to calculate changes in the length of an earth day and in the rate of the earth’s rotation.

“Utter damned rot!” is what William Berryman Scott, a former president of the American Philosophical Society, said in response to Alfred Wegener’s theory of continental drift, first proposed in 1912. “Wegener is not seeking the truth,” said a doubtful geologist, “he is advocating a cause and is blind to every argument and fact that tells against it.”