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.”

In his autobiographical novel Boyhood, Leo Tolstoy describes his youthful joy in philosophical abstraction: “I frequently imagined myself a great man, who was discovering new truths for the good of mankind, and I looked on all other mortals with a proud consciousness of my dignity.” His euphoria didn’t last. “Strange to say,” he wrote, “whenever I came in contact with these mortals, I grew timid.” Soon he was “ashamed of every simplest word and motion.”

A 52-million-year-old fossilized tomatillo found in January 2017 revealed the fruit to be five times older than scientists had previously thought. “The initial discovery was a very big OMG moment,” said paleobotanist Peter Wilf. “I was like, ‘Wait a minute, wait a minute, wait a minute. Could it be? Could it be? Could it be? Really? Really? Really?’ Then I just went nuts.”

The earliest reliable account of human flight concerns a Benedictine monk named Eilmer, who in 1066 fastened wings to his hands and feet, jumped from a tower, and glided more than six hundred feet before falling from the sky and breaking both his legs. He blamed the failure on not having fitted himself with a tail.