Eratosthenes was the middle name of Jules Brown, the second child of Emmett Brown and Clara Brown. The original Eratosthenes, known as Eratosthenes of Cyrene, was a Greek mathematician who, during the 3rd Century B.C., calculated the circumference of the Earth (with remarkable accuracy), and the tilt of the earth's axis. He also created a map of the world based on the available geographical knowledge of the era. Eratosthenes was also the first historian to calculate a chronology for describing the order of historical events, which he dated from after the conquest of Troy.
Behind the scenes
- Eratosthenes could be described as a "student of all sciences", a description that Doc Brown made of himself.
- The name, as with nearly all information about Jules Brown, is mentioned in the animated series. In Back to the Future Part III, Doc and Clara's oldest son was seen for a few seconds, and introduced only by his first name.
Wikipedia article on Eratosthenes.