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, the seat of 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............