Israel Regardie is one of the most important figures in the twentieth century development of what many have termed the Western esoteric tradition, which normally refers to the synthesis accomplished by MacGregor Mathers within the Hermetic Order of the Golden Dawn during the 1890s. Among those who proceeded to explore and build among this tradition are Israel Regardie and Aleister Crowley. In this 1968 classic, Regardie prefaces and expands upon Crowley's discovery that drugs initiate and stimulate the mystical state, providing the reader with a backgroud to Crowley's The Herb Dangerous. The English poet and mystic, Aleister Crowley had produced a series of ten large magazine-like volumes with board covers entitled The Equinox. The intention was to publish a separate issue every Spring and Autumn for five years making ten numbers in all. Openly published in them were his superbly written essays on the psychology of hashish. These were his earliest overt admissions to the occasional use of hashish as a psychedelic agent. The first four issues of this periodical contained an important serial entitled The Herb Dangerous. The opening essay, The Pharmacy of Hashish, by an English chemist, E. Whineray, was a clinical and chemical analysis of Cannabis Indica, whose first cousin is marijuana, Cannabis Sattiva. The second essay entitled The Psychology of Hashish was written by Oliver Haddo, one of the innumerable pseudonyms used by Aleister Crowley. It was succeeded in the third issue by The Poem of Hashish, written by Charles Baudelaire, and translated beautifully from the French by Crowley himself. The final installment of the serial consisted of selections from a fantastic piece of writing by H. G. Ludlow entitled The Hashish Eater. Easily a rival to de Quincy's Confessions of an Opium Eater, Ludlow's book was published by Harpers (New York, 1857). These four essays comprise the main body of this text.