The Magus, a Complete System of Occult Philosophy - Hardcoverby Francis Barrett (Author) Its author is as mysterious as its subject matter. The one appearance of English occultist FRANCIS BARRETT (b. circa 1770) upon the literary scene is this mammoth 1801 work, a complete study of ritual magic, in practice and in its theoretical underpinnings. Drawing on numerous works of the arcane and the occult, this one of a kind book ignited a fervor for magic, in all its forms, in the Europe in the early 19th century,