Davis was "discovered" around 1844 by William Levingston, a Poughkeepsie tailor who quit his trade to work with Davis to develop his clairvoyant powers for the cure of diseases. Davis's lectures, delivered while in a trance, were published as "Principles of Nature, Her Divine Revelations, and a Voice to Mankind" in 1847. Eventually, Davis progressed from mesmerism to spiritualism, as may be seen in "The Great Harmonia" (1850-52) and "The Philosophy of Spiritual Intercourse" (1856).