"These seven force-centres are frequently described in Sanskrit literature, in some of the minor Upanishads, in the Puranas and in Tantric works. They are used today by many Indian yogis. A friend acquainted with the inner life of India assures me that he knows of one school in that country which makes free use of the chakras - a school which numbers as its pupils about sixteen thousand people scattered over a large area... It appears also that certain European mystics were acquainted with the chakras. Evidence of this occurs in a book entitled Theosophia Practica by the well-known German mystic Johann Georg Gichtel, a pupil of Jacob Boehme, who probably belonged to the secret society of the Rosicrucians. It is from this work of Gichtel’s that our Plate III is reproduced by the kind permission of the publishers."