Complex sentence: The second friar was Bacon's late contemporary Thomas Bungay, who was another Franciscan, educated at Oxford (1270-1272) and at Cambridge (1282-1283) and wrote a commentary on Aristotle's "De Caelo".
Split into simpler sentences: The second friar was Bacon's late contemporary Thomas Bungay. Bungay was a fellow Franciscan who wrote a commentary on Aristotle's "De Caelo".