WHAT IS THE CAUSE OF A FEVER, OR WHETHER IT IS AN AFFECTION OF THE BODY ANNEXED TO A PRIMARY PASSION.
ERASISTRATUS gives this definition of a fever: A fever
is a quick motion of blood, not produced by our consent,
which enters into the vessels proper unto the vital spirits.
This we see in the sea; it is in a serene calm when nothing disturbs it, but is in motion when a violent preternatural wind blows upon it, and then it rageth and is circled
with waves. After this manner it is in the body of man;
when the blood is in a nimble agitation, then it falls upon
those vessels in which the spirits are, and there being in
an extraordinary heat, it fires the whole body. The opinion that a fever is an appendix to a preceding affection
pleaseth him. Diodes proceeds after this manner: Those
things which are internal and latent are manifested by
those which externally break forth and appear; and it is
clear to us that a fever is annexed to certain outward
affections, for example, to wounds, inflaming tumors, inguinary abscesses.