WHAT IS IT? "Black Bile" is one of the four "humors" or bodily fluids that make up the human body. These humors are directly related to the four basic elements: fire = yellow bile or choler; water = phlegm; earth = black bile; air = blood. A perfect balance between all four humors must be maintained lest tragedy ensue!
BLACK BILE PROS: While a profusion of Black Bile can cause melancholy, it is NOT the result of entering into congress with Satan, or bad odor as our naive ancestors once believed. An excess of Black Bile is easily cured by the placing of leeches or bloodletting by the local barber.
BLACK BILE CONS: Without treatment, Black Bile spreads throughout the body, causing hemorrhoids, gangrene, cataracts, and fistula. Though these can be cured by cauterization or by the gall from a castrated boar, an agonizing death almost always results.
CONCLUSION: Black Bile is one of the "Dangers of the Medieval World!"

WHAT ARE THEY? The smallest member of the bear family, this tiny animal is one of the forest's most useful creatures. It is often hunted by the serf to supplement his meager diet, or skinned alive to provide pelts for making shoes, lutes, or mechanical clocks.
SQUIRREL PROS: The blood of squirrel is composed of briony, opium, henbane, and the juice of hemlock; the only known cure for tuberculosis.
SQUIRREL CONS: The squirrel is widely renown for collecting nuts, unscrewing their tops, and filling them with the yellow bile of the dead. They take these nuts and slip them into the noses of sleeping children, subsequently causing a disease that eventually wiped out half of Europe; the BLACK PLAGUE. (See "Dangers of the Medieval World #5: THE BLACK PLAGUE")
CONCLUSION: Squirrels are one of the "Dangers of the Medieval World!"