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...

Galen of Pergamon (c. 129 - 216 AD) is well known in the history of medicine. His extensive writings and theories prevail for over 2000...

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

Iodine (I) is an essential element in biology, industry, science and health. It's known for its intense violet gas and strong odor....

Scheele's Green is a rich, vibrant green. Its color appeal surpasses that of the copper carbonate paints of the late 18th century and...

Carl Wilhelm Scheele (1742 - 1786) is a self-taught German-Swedish chemist whose work has strong impact on chemical sciences of the day....

Vorticella is a genus of single-celled water-loving organisms with specialized cilia. As an adult the microbe attaches to a substrate...

Microbial corrosion of concrete by bacteria, fungi and algae destabilize structures of home and environs. While the impact of weather,...

Silverpoint is a drawing medium with distinct artistic potential. This delicate and precise medium has a rich history, unique properties,...

Drawing is a creative expression for humans since cave paintings of prehistory. In art, anything making a mark is a drawing tool....

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

Chloroauric acid H[AuCl4] is a yellow solution created in the 18th century. A gold(III) salt, chloroauric acid is an innovative compound,...

Alchemy these days is often seen only as a mystical practice purveying the clic hé of turning base metals into gold. Alchemy is in fact...

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

Radon (Rn) is part of the noble gas family. Colorless, odorless, and tasteless, radon presents unique characteristics and effects on...

Antonie van Leeuwenhoek (1632 - 1723) is a self-taught scientist whose work in microscopy revolutionizes medicine and other disciplines....

Acidophillium and Acidobacillus ferroxidens bacteria thrive in harmful conditions. These microscopic sulfuric acid-producing bacteria...

Thiobacillus, Thiothrix, and Beggiatoa are genera of acid-producing bacteria with significant contributions to creation of sulfuric...

Protozoa are single-celled organisms integral to ecosystems worldwide. As microbes they're microscopic and invisible to the human eye....