 Randolph first discussed the "sleep of Sialam" in his 1873 work "Ravalette," but described it at the time as a once-in-a-century prophetic trance.In later writings, Randolph used the term as a more general form of clairvoyant sleep used to understand spiritual things.Helena Blavatsky may also have taught the technique, calling it the "Sleep of Siloam."