Treponema pallidum is a parasitic spirochete or spiral bacterium, primarily known for causing the STI syphilis . It's tricky to...

Syphilis is a sexually transmitted infection (STI) of obscure origins, a spotty history and massive impact. In the Renaissance its...

Fermentation in brewing transforms sugar into alcohol through the action of a vast colony of one-celled, immotile microbes. Top...

Krausen is a joyful moment in brewing and fermenting. When krausen appears, fermentation is under way. When it falls, fermentation is...

Feudalism is a structured system of land ownership and governance in which the rich get richer and the poor get poorer. It includes a...

Vulcano is part of the Aeolian Island archipelago of Italy. Named for Vulcan, Roman god of fire and metalworking, Vulcano is a unique...

Sublimation is a process of refinement, purification or extraction of specific elements. The aludel, a unique alchemical apparatus, is...

Zaffre (zaffer) is a vibrant deep blue pigment developed by alchemists, major pigment creators, by c. 1550 AD. Characterized by brilliant...

Flowers of antimony are a purified form of antimony trioxide (Sb2O3). Created through sublimation, they have chemical and medical...

Glass of antimony , or vitrum antimonii , gives warm yellow or red hues. As Sb2O3, its use in alchemy is largely medicinal, one of many...

Johann Georg Faust or Doctor Faustus is an alchemist, physician and magician, a cryptic figure of the German Renaissance. Perceived by...

The German Peasants' War (1524-5) is short, bloody and violent, and changes the course of history in Europe. Up to 400,000 peasants rise...

The Nine Years War, also known as the War of the League of Augsburg, is a key conflict in European history. Fierce battles erupt,...

Liver of Sulfur is a unique compound of alchemy, metallurgy and medicine. Also known as hepar sulfuris or sulfurated potash, Liver of...

Diana's Tree ( Arbor Diana or Dianae ) is one of the most intriguing creations of alchemy. Its delicate branches of crystallized silver...

Lye or sodium hydroxide (NaOH) is a vital part of human history. Also called caustic soda, lye is a white odorless solid. A strong...

Potash is a mineral group prized in agriculture, health and human life though history. Potash covers various potassium-rich salts,...

Metal salts are compounds created from metals and acids. In history and today they enjoy uses in beauty, natural health, chemical...

Sanguine is a rich, reddish-brown chalk beloved by Renaissance artists such as Michelangelo. Creating flesh-like tones in the human form...

Hydrochloric acid is a powerful chemical. Used from old alchemical practices to modern times, this colorless, pungent-smelling liquid is...