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.

Students at the Federal Polytechnic Institute in Zurich wrote to Carl Jung in 1949 to ask what effect he thought technology had on the human psyche. “The danger lies not in technology,” Jung responded, “but in the possibilities awaiting discovery.” The question regarding new discoveries was “whether man is sufficiently equipped with reason to be able to resist the temptation to use them for destructive purposes.” This, Jung concluded, “experience alone can answer.”

Hero of Alexandria invented the aeolipile, a primitive steam engine, in the first century. A hollow sphere with elbow-shaped tubes mounted on an axle and suspended over a cauldron of boiling water, the engine likely could not have powered anything. “It should probably be remembered,” wrote historian William Rosen, “as the first in a line of engineering dead ends.”

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.