Modern Magic: A Practical Treatise on the Art of Conjuring

CHAPTER VII. SPIRITUALISM. The belief in the materialization of spirits, and the visits of spiritual inhabitants of another world to the scene of their mortal sojourn for the sole object of giving specimens of their caligraphy on slates and ceilings, rapping and playing upon tambourines, sealed accordions, guitars, and so forth, affords another proof that there are no bounds to human credulity and stupidity.