SPIRITUALISM, SEANCES AND SLATE WRITING - EGLINGTON Lithograph showing the method of obtaining spirit writing on two slates, held over the seance table. 'The actual production of the (spirit) writing without visible agency has also been witnessed', and in almost every case the sound of writing being done by an invisible agency is heard during the seances. From John S. Farmer, Twixt Two Worlds. A Narrative of the Life and Work of William Eglington, 1886.