Back in the day, the medical analysis of urine relied on, well, a doctor's five senses and superstition. But sometimes physicians needed a little extra help in divining the ramifications of some dubious tinkle.
Enter the urine wheel, a diagram that doctors consulted to determine what maladies corresponded with the cloudiness, bouquet, and taste of the afflicted's golden outpourings.
Even though uroscopy was far from an exact art, it did get some things right, such as diagnosing diabetes mellitus. It also got many things wrong, occasionally in downright Pythonian ways. As the magazine Doctors Review elaborates:
One of the rare instances in which uroscopy was dead-on came in diagnosing diabetes by a sweet taste to the urine. In 1674, English physician Thomas Willis (1621-1675) was the first in modern medical literature to observe this relationship. He may have enjoyed the sampling process a little too much, stating that the pee on his palate was "wonderfully sweet as if it were imbued with honey or sugar." His taste test led him to add the term "mellitus" to this form of diabetes, from the Latin word for honey. Ancient Arab, Hindu and Chinese texts also have anecdotal reports of the same sweet taste in urine from patients who displayed the symptoms of what was later termed diabetes.
Urine was also used as a way to identify pure evil. As the witch hunts of Europe reached a fever pitch in the 16th and 17th centuries, self-proclaimed witch-hunters and appointed tribunals determined the guilt of countless "witches" based on whether or not the cork popped out of a bottle containing a combination of their urine and metal objects like pins and nails.
In any case, remember Pliny's advice — spit into your urine immediately to prevent anybody from cursing you. You can see more urine wheels at Edible Geography.
Images: Hans von Gersdorff, Feldtbüch der Wundartzney, 1517. Urine wheel by Ullrich Pinder, 1506.