ordinate causes. By these,
according to his opinion, the quality of the air, and of the other
elements, was so altered that they set poisonous fluids in motion towards
the inward parts of the body, in the same manner as the magnet attracts
iron; whence there arose in the commencement fever and the spitting of
blood; afterwards, however, a deposition in the form on glandular
swellings and inflammatory boils. Herein the notion of an epidemic
constitution was set forth clearly, and conformably to the spirit of the
age. Of contagion, Guy de Chauliac was completely convinced. He sought
to protect himself against it by the usual means; and it was probably he
who advised Pope Clement VI. to shut himself up while the plague lasted.
The preservation of this Pope's life, however, was most beneficial to the
city of Avignon, for he loaded the poor with judicious acts of kindness,
took care to have proper attendants provided, and paid physicians himself
to afford assistance wherever human aid could avail--an advantage which,
perhaps, no other city enjoyed. Nor was the treatment of plague-patients
in Avignon by any means objectionable; for, after the usual depletions by
bleeding and aperients, where circumstances required them, they
endeavoured to bring the buboes to suppuration; they made incisions into
the inflammatory boils, or burned them with a red-hot iron, a practice
which at all times proves salutary, and in the Black Plague saved many
lives. In this city, the Jews, who lived in a state of the greatest
filth, were most severely visited, as also the Spaniards, whom Chalin
accuses of great intemperance.

Still more distinct notions on the causes of the plague were stated to
his contemporaries in the fourteenth century by Galeazzo di Santa Sofia,
a learned man, a native of Padua, who likewise treated plague-patients at
Vienna, though in what year is undetermined. He distinguishes carefully
_pestilence_ from _epidemy_ and _endemy_. The common notion of the two
first accords exactly with that of an epidemic constitution, for both
consist, according to him, in an unknown change or corruption of the air;
with this difference, that pestilence calls forth diseases of different
kinds; epidemy, on the contrary, always the same disease. As an example
of an epidemy, he adduces a cough (influenza) which was observed in all
climates at the same time without perceptible cause; but he recognised
the approach of a pestilence, independe