This great epidemic of the Middle Ages is considered by many modern writers as one of the forms of ergotism, notwithstanding the contrary conclusions arrived at by the Commission of 1776, composed of such men as Jussieu, Paulet, Saillant, and Teissier, who were ordered to report as to the nature of the disease by the Royal Society. According to the work of this Commission the _mal des ardents_ was a variety of plague, with buboes, carbuncles and petechial spots, while St. Anthony’s fire was only gangrenous ergotism. This is a remarkable example of the confusion into which scientific facts were allowed to fall through the fault of careless authors. It is in such instances that we may estimate the importance of history. We find in the “Chronicles of Frodoard,” in the year 945, the following: “The year 945, in the history of Paris and its numerous suburban villages, a disease called _ignis plaga_ attacked the limbs of many persons, and consumed them entirely, so that death soon finished their sufferings. Some few survived, thanks be to the intercession of the Saints; and even a considerable number were cured in the Church of Notre Dame de Paris. Some of these, believing themselves out of danger, left the church; but the fires of the plague were soon relighted, and they were only saved by returning to Notre Dame.” Sauvel, the translator of Frodoard, remarks that at this epoch the Church of Notre Dame served as a hospital for the sick attacked by the epidemic, and sometimes contained as high as six hundred patients. Another historian of the time was Raoul Glaber,[15] who mentions that “in 993 a murderous malady prevailed among men. This was a sort of hidden fire, _ignis occultus_, the which attacked the limbs and detached them from the trunk after having consumed the members. Among some the devouring effect of this fire took place in a single night. “In 1039,” continues our author, “divine vengeance again descended on the human race with fearful effect and destroyed many inhabitants of the world, striking alike the rich and the poor, the aristocrat and the peasant. Many persons lost their limbs and dragged themselves around as an example to those who came after them.” In the _Chronicle of France_, from the commencement of the Monarchy up to 1029,[16] the monk Adhemar speaks of the epidemic in the following terms: “In these times a pestilential fire (_pestilential ignis_) attacked the population of Limousin; an infinite number of persons of both sexes were consumed by an invisible fire.”