An encyclopaedia of occultism : a compendium of information on the occult sciences, occult personalities, psychic science, magic, demonology, spiritism and mysticism

Lewis Spence’s encyclopaedia is a reference work that surveys the wide field of occult studies, from ritual magic and spirit communication to mysticism and psychic phenomena. Historically, it reflects early 20th-century efforts to organize esoteric knowledge for a general readership, and it offers concise entries on ideas, figures, and practices across the occult tradition.

Lewis Spence (1874–1955) was a Scottish journalist, folklorist, and prolific writer on mythology, religion, and occult subjects. His books on Atlantis, occultism, and comparative mythology were influential in early twentieth-century esoteric and popular scholarly literature.