There is no ground for believing that in the fourteenth century men of this kind were publicly questioned regarding their views; and it is, therefore, the more necessary that impartial history should take up their cause, and do justice to their merits.
The first notice on this subject is due to a very celebrated teacher in Perugia, Gentilis of Foligno, who, on the 18th of June, 1348, fell a sacrifice to the plague, in the faithful discharge of his duty.

Attached to Arabian doctrines, and to the universally respected Galen, he, in common with all his contemporaries, believed in a putrid corruption of the blood in the lungs and in the heart, which was occasioned by the pestilential atmosphere, and was forthwith communicated to the whole body.

He thought, therefore, that everything depended upon a sufficient purification of the air, by means of large blazing fires of odoriferous wood, in the vicinity of the healthy as well as of the sick, and also upon an appropriate manner of living, so that the putridity might not overpower the diseased.

In conformity with notions derived from the ancients, he depended upon bleeding and purging, at the commencement of the attack, for the purpose of purification; ordered the healthy to wash themselves frequently with vinegar or wine, to sprinkle their dwellings with vinegar, and to smell often to camphor, or other volatile substances.

Hereupon he gave, after the Arabian fashion, detailed rules, with an abundance of different medicines, of whose healing powers wonderful things were believed.