Leopold of Austria's 13th Century Compilation of the Science of the Stars is a well-known collection of numerous Arabic astrologers' works excerpted in Latin. Sometimes called a "shorter Bonatti," Leopold discusses traditional astronomy, basic interpretive principles, Lots or "Arabic Parts," natal astrology, questions or horary, mundane topics such as weather and wars, elections, and even material on using astrological talismans. This book was translated and edited by Benjamin Dykes, whose long experience with the source texts makes Leopold's text more readable and understandable, correcting many errors committed by the medieval editors and typesetters. With numerous special Comments, tables, and diagrams added by Dykes in addition to Leopold's own images, the Compilation is a handy resource for students and experts in medieval Western astrology.