Finding fresh perspectives on Islam’s contributions to medieval Western science is not easy. Falk, a University of Cambridge science historian, manages to do just that through the eyes of little-known 14th-century English cleric and astrologer John of Westwyk. John’s journey of discovery through sundry monastic libraries exposed him to manuscripts that inspired his own magnum opus, Equatorie [Computer] of the Planetis. Examining the Albion, a famed contemporary English astrolabe, John noted that it featured “attributes of earlier instruments” including those designed by 11th-century Andalusi astronomer al-Zarqali. These and other influences on John’s own scholarship reemphasizes how “respect for ancient learning and study of ancient texts,” especially those of Muslim scholars, were “a key feature of the Middle Ages.”