"If we now glance back over the pages of all the religious martyrdoms, bringing sinister recollections of the Inquisition and various mass-madnesses, a not exaggerated picture of a true epidemic will emerge quite clearly. Just as any epidemic, this malady of madness flared up suddenly, seemingly from a small beginning, and grew with extraordinary speed into most violent forms. We are reminded of the various persecutions of “witches,” which are even hard to believe. In the recent writings of Dr. Lévi-Valency several curious details are related which remind one again of the possibility of an epidemic of madness. Ch. 19 Epidemics"