Ancient Astrology Theory and Practice: Matheseos Libri VIII;

The translator, Jean Rhys Bram, writes, "Magic, philosophy, science and theology combine in strange ways in the thinking of the last centuries of the Roman empire..... Firmicus seemed worthy of note for many reasons. He is almost alone as author of works produced both before and after an apparent conversion to Christianity.... He left a lengthy handbook detailing the astrological practices of his day, the only work which has come down to us in its entirety [90% complete: Holden] out of numerous astrological treatises written in the Hellenistic and Roman periods..... This manual was important because it was the channel for astrological lore to the Middle Ages and Renaissance." (from the Preface)

One of the finest of all ancient astrological texts, this is also one of the best-translated.