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Sylvia Rose

Urine in Medieval Alchemy & Medicine

In the medieval world, urine is a surprisingly versatile body fluid with a wide range of applications beyond the obvious disposal function. While today pee is seen as waste, up to the 19th century it's valued for chemical properties and medical diagnosis.




shower of gold


A common use of medieval pee is in the textile industry, where it's applied to processes such as dyeing wool and tanning leather. The ammonia in urine is a mordant to help fix dyes to fabrics for vibrant colors. A collection barrel is offered for people to empty their chamber pots.


In medieval medicine, attributes of urine include cleansing and antiseptic properties, making pee a common ingredient in poultices and ointments. Medieval physicians use urine as a diagnostic tool. Several factors help assess a patient's health.



Al-Razi diagnoses a patient based on pee color, smell, sediment


Above: Persian doctor Al-Razi, in "Recueil des traités de médecine" 1250-1260 by Gerardus Cremonensis. Al-Razi holds a matula, a specialized glass vessel for collecting and examination of the urine.


Urine is a ubiquitous ingredient of alchemy, which is especially known for gold-making but also has deep connections to fabric, gem and metal dyes, and ancient medicine. Alchemists extract compounds of urine in experiments, boldly going where no one has gone before.



Retort or alembic for distilling and condensing materia
Retort or alembic for distilling and condensing material

Because of its golden color some alchemists or patrons associate urine with gold, and Urine is one of many code words for the prima materia or First Matter of alchemy. Urine the body fluid is readily available and best of all, cheap. Alchemists are notoriously low on funds.



Such is the case with Hennig Brand, the German alchemist who discovers phosphorus in 1669 by boiling and otherwise processing his urine. He spends his first wife's fortune on alchemy and puts a grievous dent in that of his second wife before his eureka moment.



Hennig Brand discovers phosphorus (The Alchemist Discovering Phosphorus, 1771, Joseph Wright)
Hennig Brand discovers phosphorus (The Alchemist Discovering Phosphorus, 1771, Joseph Wright)

Many alchemists believe in urine's esoteric qualities, using distillation and other processes to extract its elements. They want to uncover the secrets of pee for medicinal or philosophical purposes, or the incorrigible curiosity factor inherent in all humans.


Alchemy practitioners seek to release chemical or spiritual virtues of urine through a series of elaborate procedures. These can include aging the pee, fermentation, boiling, slow heating, cohobation (repeated distillation) and eclectic combinations with other substances.



a golden liquid is poured


For some, purity of body and spirit is significant, taking a holistic approach to achieving a state of balance and harmony. Practitioners often engage in rituals, exercises, and lifestyle choices to cleanse not only the physical body but also the mind and soul.


Medieval doctors conduct physical examinations of patients, including analysis of urine. Uroscopy is pivotal to medical diagnostics. Color, sediment, smell, and taste of urine can reveal crucial information about the patient's health.



Medieval Urine Analysis Chart (Latin)
Medieval Urine Analysis Chart (Latin)

Medieval doctors are trained to observe up to 30 distinct features in urine to aid in diagnosis. Each characteristic is noted and analyzed to form a comprehensive picture of the patient's condition. Urine analysis also determines the course of treatment.


The significance of uroscopy is such that in many regions, the urine flask or matula becomes synonymous with the profession of a doctor. It symbolizes the expertise of the practitioner in understanding details of bodily fluids and using that knowledge to heal illness.



the magic elixir


Around 1267 AD, medieval friar and alchemist Roger Bacon discovers gunpowder in the West after another friar shows him Chinese firecrackers. His mix is 29.5% sulfur, 29.5% charcoal, and 41% saltpeter. After some tweaks it's found the best ratio is 10:15:75.


Due to its chemical composition urine has been used in making gunpowder. In 1863, during the Civil War, Confederate chemist Jonathan Harrelson figures out how to create more potassium nitrate, or saltpeter, by extracting it from human urine.



Confederate Soldiers
Confederate Soldiers, US Civil War (1861 - 1865 AD) re-enactment

Fermented urine is also a popular fixer for blue woad dye.


Non-Fiction Books:


Fiction Books:

READ: Lora Ley Adventures - Germanic Mythology Fiction Series

READ: Reiker For Hire - Victorian Detective Murder Mysteries











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