List of medieval European scientists
  • Anthemius of Tralles (ca. 474 – ca. 534): a professor of geometry and architecture, authored many influential works on mathematics and was one of the architects of the famed Hagia Sophia, the largest building in the world at its time. His works were among the most important source texts in the Arab world and Western Europe for centuries after.
  • John Philoponus (ca. 490–ca. 570): also known as John the Grammarian, a Christian Byzantine philosopher, launched a revolution in the understanding of physics by critiquing and correcting the earlier works of Aristotle. In the process he proposed important concepts such as a rudimentary notion of inertia and the invariant acceleration of falling objects. Although his works were repressed at various times in the Byzantine Empire, because of religious controversy, they would nevertheless become important to the understanding of physics throughout Europe and the Arab world.
  • Paul of Aegina (ca. 625–ca. 690): considered by some to be the greatest Christian Byzantine surgeon, developed many novel surgical techniques and authored the medical encyclopedia Medical Compendium in Seven Books. The book on surgery in particular was the definitive treatise in Europe and the Islamic world for hundreds of years.
  • The Venerable Bede (ca. 672–735): a Christian monk of the monasteries of Wearmouth and Jarrow who wrote a work On the Nature of Things, several books on the mathematical / astronomical subject of computus, the most influential entitled On the Reckoning of Time. He made original discoveries concerning the nature of the tides and his works on computus became required elements of the training of clergy, and thus greatly influenced early medieval knowledge of the natural world.
  • Rabanus Maurus (c. 780 – 856): a Christian monk and teacher, later archbishop of Mainz, who wrote a treatise on Computus and the encyclopedic work De universo. His teaching earned him the accolade of "Praeceptor Germaniae," or "the teacher of Germany."
  • Abbas Ibn Firnas (810 – 887): a polymath and inventor in Muslim Spain, made contributions in a variety of fields and is most known for his contributions to glass-making and aviation. He developed novel ways of manufacturing and using glass. He broke his back at an unsuccessful attempt at flying a primitive hang glider in 875.
  • Pope Sylvester II (c. 946–1003): a Christian scholar, teacher, mathematician, and later pope, reintroduced the abacus and armillary sphere to Western Europe after they had been lost for centuries following the Greco-Roman era. He was also responsible in part for the spread of the Hindu-Arabic numeral system in Western Europe.
  • Maslamah al-Majriti (died 1008): a mathematician, astronomer, and chemist in Muslim Spain, made contributions in many areas, from new techniques for surveying to updating and improving the astronomical tables of al-Khwarizmi and inventing a process for producing mercury oxide.[citation needed] He is most famous, though, for having helped transmit knowledge of mathematics and astronomy to Muslim Spain and Christian Western Europe.
  • Abulcasis (936-1013): a physician and scientist in Muslim Spain, is considered to be the father of modern surgery. He wrote numerous medical texts, developed many innovative surgical instruments, and developed a variety of new surgical techniques and practices. His texts were considered the definitive works on surgery in Europe until the Renaissance.
  • Constantine the African (c. 1020&–1087): a Christian native of Carthage, is best known for his translating of ancient Greek and Roman medical texts from Arabic into Latin while working at the Schola Medica Salernitana in Salerno, Italy. Among the works he translated were those of Hippocrates and Galen.
  • Arzachel (1028–1087): the foremost astronomer of the early second millennium, lived in Muslim Spain and greatly expanded the understanding and accuracy of planetary models and terrestrial measurements used for navigation. He developed key technologies including the equatorium and universal latitude-independent astrolabe.
  • Avempace (died 1138): a famous physicist from Muslim Spain who had an important influence on later physicists such as Galileo. He was the first to theorize the concept of a reaction force for every force exerted.
  • Adelard of Bath (c. 1080 – c. 1152): was a 12th-century English scholar, known for his work in astronomy, astrology, philosophy and mathematics.
  • Avenzoar (1091–1161): from Muslim Spain, introduced an experimental method in surgery, employing animal testing in order to experiment with surgical procedures before applying them to human patients.[4] He also performed the earliest dissections and postmortem autopsies on both humans as well as animals.
  • Robert Grosseteste (1168–1253): Bishop of Lincoln, was the central character of the English intellectual movement in the first half of the 13th century and is considered the founder of scientific thought in Oxford. He had a great interest in the natural world and wrote texts on the mathematical sciences of optics, astronomy and geometry. In his commentaries on Aristotle's scientific works, he affirmed that experiments should be used in order to verify a theory, testing its consequences. Roger Bacon was influenced by his work on optics and astronomy.
  • Albert the Great (1193–1280): Doctor Universalis, was one of the most prominent representatives of the philosophical tradition emerging from the Dominican Order. He is one of the thirty-three Saints of the Roman Catholic Church honored with the title of Doctor of the Church. He became famous for his vast knowledge and for his defence of the pacific coexistence between science and religion. Albert was an essential figure in introducing Greek and Islamic science into the medieval universities, although not without hesitation with regard to particular Aristotelian theses. In one of his most famous sayings he asserted: "Science does not consist in ratifying what others say, but of searching for the causes of phenomena." Thomas Aquinas was his most famous pupil.
  • John of Sacrobosco (c. 1195 – c. 1256): was a scholar, monk, and astronomer (probably English, but possibly Irish or Scottish) who taught at the University of Paris and wrote an authoritative and influential mediaeval astronomy text, the Tractatus de Sphaera; the Algorismus, which introduced calculations with Hindu-Arabic numerals into the European university curriculum; the Compotus ecclesiasticis on Easter reckoning; and the Tractatus de quadrante on the construction and use of the astronomical quadrant.
  • Jordanus de Nemore (late 12th, early 13th century): was one of the major pure mathematicians of the Middle Ages. He wrote treatises on mechanics ("the science of weights"), on basic and advanced arithmetic, on algebra, on geometry, and on the mathematics of stereographic projection.
  • Villard de Honnecourt (fl. 13th century): a French engineer and architect who made sketches of mechanical devices such as automatons and perhaps drew a picture of an early escapement mechanism for clockworks.
  • Roger Bacon (1214–94): Doctor Admirabilis, joined the Franciscan Order around 1240 where, influenced by Grosseteste, Alhacen and others, he dedicated himself to studies where he implemented the observation of nature and experimentation as the foundation of natural knowledge. Bacon wrote in such areas as mechanics, astronomy, geography and, most of all, optics. The optical research of Grosseteste and Bacon established optics as an area of study at the medieval university and formed the basis for a continuous tradition of research into optics that went all the way up to the beginning of the 17th century and the foundation of modern optics by Kepler.[8]
  • Ibn al-Baitar (died 1248): a botanist and pharmacist in Muslim Spain, researched over 1400 types of plants, foods, and drugs and compiled pharmaceutical and medical encyclopedias documenting his research. These were used in the Islamic world and Europe until the 19th century.
  • Theodoric Borgognoni (1205-1296): was an Italian Dominican friar and Bishop of Cervia who promoted the uses of both antiseptics and anaesthetics in surgery. His written work had a deep impact on Henri de Mondeville, who studied under him while living in Italy and later became the court physician for King Philip IV of France.
  • William of Saliceto (1210-1277): was an Italian surgeon of Lombardy who advanced medical knowledge and even challenged the work of the renowned Greco-Roman surgeon Galen (129-216 AD) by arguing that allowing pus to form in wounds was detrimental to the health of he patient.
  • Thomas Aquinas (1227–74): Doctor Angelicus, was an Italian theologian and friar in the Dominican Order. As his mentor Albert the Great, he is a Catholic Saint and Doctor of the Church. In addition to his extensive commentaries on Aristotle's scientific treatises, he was also said to have written an important alchemical treatise titled Aurora Consurgens. However, his most lasting contribution to the scientific development of the period was his role in the incorporation of Aristotelianism into the Scholastic tradition.
  • Arnaldus de Villa Nova (1235-1313): was an alchemist, astrologer, and physician from the Crown of Aragon who translated various Arabic medical texts, including those of Avicenna, and performed optical experiments with camera obscura.
  • John Duns Scotus (1266–1308): Doctor Subtilis, was a member of the Franciscan Order, philosopher and theologian. Emerging from the academic environment of the University of Oxford. where the presence of Grosseteste and Bacon was still palpable, he had a different view on the relationship between reason and faith as that of Thomas Aquinas. For Duns Scotus, the truths of faith could not be comprehended through the use of reason. Philosophy, hence, should not be a servant to theology, but act independently. He was the mentor of one of the greatest names of philosophy in the Middle Ages: William of Ockham.
  • Mondino de Liuzzi (c. 1270-1326): was an Italian physician, surgeon, and anatomist from Bologna who was one of the first in Medieval Europe to advocate for the public dissection of cadavers for advancing the field of anatomy. This followed a long-held Christian ban on dissections performed by the Alexandrian school in the late Roman Empire.
  • William of Ockham (1285–1350): Doctor Invincibilis, was an English Franciscan friar, philosopher, logician and theologian. Ockham defended the principle of parsimony, which could already be seen in the works of his mentor Duns Scotus. His principle later became known as Occam's Razor and states that if there are various equally valid explanations for a fact, then the simplest one should be chosen. This became a foundation of what would come to be known as the scientific method and one of the pillars of reductionism in science. Ockham probably died of the Black Plague. Jean Buridan and Nicole Oresme were his followers.
  • Jacopo Dondi dell'Orologio (1290-1359): was an Italian doctor, clockmaker, and astronomer from Padua who wrote on a number of scientific subjects such as pharmacology, surgery, astrology, and natural sciences. He also designed an astronomical clock.
  • Richard of Wallingford (1292-1336): an English abbot, mathematician, astronomer, and horologist who designed an astronomical clock as well as an equatorium to calculate the lunar, solar and planetary longitudes, as well as predict eclipses.
  • Jean Buridan (1300–58): was a French philosopher and priest. Although he was one of the most famous and influent philosophers of the late Middle Ages, his work today is not renowned by people other than philosophers and historians. One of his most significant contributions to science was the development of the theory of impetus, that explained the movement of projectiles and objects in free-fall. This theory gave way to the dynamics of Galileo Galilei and for Isaac Newton's famous principle of Inertia.
  • Guy de Chauliac (1300-1368): was a French physician and surgeon who wrote the Chirurgia magna, a widely read publication throughout medieval Europe that became one of the standard textbooks for medical knowledge for the next three centuries. During the Black Death he clearly distinguished Bubonic Plague and Pneumonic Plague as separate diseases, that they were contagious from person to person, and offered advice such as quarantine to avoid their spread in the population. He also served as the personal physician for three successive popes of the Avignon Papacy.
  • John Arderne (1307-1392): was an English physician and surgeon who invented his own anesthetic that combined hemlock, henbane, and opium. In his writings, he also described how to properly excise and remove the abscess caused by anal fistula.
  • Nicole Oresme (c. 1323–82): was one of the most original thinkers of the 14th century. A theologian and bishop of Lisieux, he wrote influential treatises in both Latin and French on mathematics, physics, astronomy, and economics. In addition to these contributions, Oresme strongly opposed astrology and speculated about the possibility of a plurality of worlds.
  • Giovanni Dondi dell'Orologio (c. 1330-1388): was a clockmaker from Padua, Italy who designed the astarium, an astronomical clock and planetarium that utilized the escapement mechanism that had been recently invented in Europe. He also attempted to describe the mechanics of the solar system with mathematical precision.

Creating a better biofuel from poop

When it comes to liquid fuels, the market is dominated by gasoline, diesel and jet fuel—all compounds derived from crude oil. These fuels are highly energy dense, cheap and (for now) abundant.

But for years, scientists have been working toward a secure and sustainable alternative to fossil fuels.

Ethanol, one of the earliest biofuel that’s largely derived from corn, hasn’t been able to compete with liquid fossil fuels. It isn’t particularly energy-dense and you need special modifications on your car to use ethanol or similar biofuels.

But researchers at UCLA are working on the next generation of advanced biofuels like Isobutanol.

“We try to produce branched-chain alcohols, that are a little larger, more energy dense and burn more like real gasoline,” explains UCLA researcher David Wernick.

Unlike ethanol, these biofuels are compatible with current fuel infrastructure, which means that you could use them with your current car.

By engineering bacteria (Bacillus subtilis), Wernick and his UCLA cohorts have enabled these tiny organisms to break down manure and other protein-rich waste like wastewater algae and byproducts from fermenting wine and beer.  

Once the protein is broken down, the bacteria convert it into biofuel and ammonia, which can be used for fertilizer. The next step is scaling up the process and improving the amount of biofuel produced.

Learn more about the lab and their process of transforming poop and protein waste into fuel:

Medicinal Herbs & Uses: Mugwort


Mugwort: Artemisia vulgaris

Herb Properties and Medicinal Uses

Properties   Mugwort leaves are edible, young leaves are boiled as a pot herb or used in salad, they aid in digestion although said to have a bitter taste. Used for centuries as an alternative medicine, it is antibacterial, anthelmintic, anti-inflammatory, antiseptic, antispasmodic, carminative, cholagogue, diaphoretic, digestive, diuretic, emmenagogue, expectorant, haemostatic, nervine, purgative, stimulant, stomachic, and tonic, cleansing toxins from the blood. An infusion of the leaves and flowering tops is used in the treatment of all matters connected to the digestive system, it increases stomach acid and bile production, eases gas and bloating, improving digestion, the absorption of nutrients and strengthening the entire digestive system. It is used in alternative medicine to expel intestinal worms, nervous and spasmodic affections, asthma, sterility, functional bleeding of the uterus and menstrual complaints, and diseases of the brain. As a gargle for sore throat, a wash for sores and a poultice for infections, tumors and to stop bleeding. These actions and uses are now backed by scientific studies on the plants main constituents volatile oils containing 1,8-cineole, artemisin, azulenes sesquiterpene lactones, flavonoids, coumarin derivatives, tannins, thujone and triterpenes. The leaves have an antibacterial action, inhibiting the growth of Staphococcus aureus, Bacillus typhi, B. dysenteriae, streptococci, E. coli, B. subtilis, and pseudomonas. A weak tea made from the infused plant is a good all-purpose insecticide. The fresh or the dried plant repels insects.Caution: Should not be used by pregnant women since it can cause a miscarriage.


Perennial herb native to Africa, temperate Asia, and Europe, widely naturalized in most parts of the world. Found growing on hedgebanks and waysides, uncultivated and waste land. Cultivation is fairly easy Mugwort prefers slightly alkaline, well-drained loamy soil, in a a sunny position. A tall-growing shrubby plant, with angular stems, which are and often purplish, growing 3 feet or more in height. The leaves are smooth and dark green above and covered with a cottony down beneath. They are alternate, pinnately lobed, and segmented. The small greenish yellow flowers are panicled spikes with a cottony appearance. Blooming is from July to October. Mugwort is closely related to Common Wormwood (Absinthe). Gather leaves and stems when in bloom, dry for later herb use.


 In Native American folklore Mugwort was also a Witchcraft medicine, rubbed the leaves on ones body to keep ghosts away or wearing a necklace to prevent dreaming of the dead. In the Middle Ages a crown made from its sprays was worn on St. John’s Eve to gain security from evil possession. Mugwort derived its common name from being used to flavor drinks like beer before the introduction of hops. The Name Artemisia is from the Goddess Artemis (1st century AD) who inspired the plants genus name.

Recipe Medicinal tea: Steep 1 tsp. dried herb in a cup boiling water, take in mouthful doses throughout the day.

  • Mugwort:

Medicinal Use: Leaf tea diuretic, induces sweating. Regulates erratic menstruation, brings on delayed periods, expels afterbirth, helps with menopausal symptoms. Promotes appetite and bile production, tonic for digestion. Tonic for nerves; mild sedative. Used for bronchitis, colds, colic, kidney ailments, fevers. Bath additive for rheumatism and tired legs. Juice relieves itching of poison oak. Disinfectant and antiseptic. Used for moxibustion.

Traditional Magical Use: In the Middle Ages, mugwort was connected with St. John the Baptist, who was said to have worn a belt of the herb during his time in the wilderness. St. John’s Herb, as the plant became known, had the power to drive out demons, and sprays of the herbs were worn around the head on St. John’s Eve as a protection against possession by evil forces. In China, bunches of mugwort were hung in the home during the Dragon Festival to keep away evil spirits. The Ainus of Japan burn bunches to exorcise spirits of disease, who are thought to hatethe odor. Planted along roadsides by the Romans, who put sprigs in their shoes to prevent aching feet on long journeys. Carry to ward against wild beasts, poison, and stroke. Prevents elves and other evil things from entering houses. Said to cure madness and aid in astral projection.

A pillow stuffed with mugwort and slept upon will produce prophetic dreams. Mugwort is burned during scrying rituals, and a mugwort-and-honey infusion is drunk before divination. The infusion is also used to wash crystal balls and magic mirrors, and mugwort leaves are placed around the base of the ball, or beneath it, to aid in psychic workings. Pick just before sunrise on the waxing moon, preferably from a plant that leans north. A Roman invocation to be used when picking mugwort is: Tollam te artemisia, ne lassus sim in via.

Shamanic Magical Use: This is the plant of Midgard, burned at the start of a ritual. One starts and ends with Mugwort, as one starts and ends with Midgard. Its shamanic purpose is purification. We tend to think of purification, in these days of advanced medical antisepsis, as being sterile. To us, “pure” has come to mean “without life”. When we use something whose basic power is purification, we expect, on some level, for it to clean everything and leave it a blank slate. However, that’s not what magical purification actually does.

Mugwort is the herb that is most often burned as recels, the Old English word for incense; pronounced ray-kels. The act of burning it is referred to as recaning, which can be pronounced various ways, but the most graceful seems to be reek-en-ing; the verb recan is cognate to our work “reek”. Celtic-tradition people use the term saining. It’s an alternative to the Native American-derived term “smudging”, and it can be bound in lashed bundles and burned in the same way as white sagebrush. It also has a clearing effect on the mind, and a heightening of the extra senses, so it is a good thing to start any working that is going to involve an altered or trance state at some point.

Turning Poop into Fuel

UCLA alum David Wernick is essentially trying to solve two problems at once. One is that he’s trying to find a renewable alternative to fossil fuels. The second problem is the 1 billion tons of manure that the U.S. produces each year alone.

That mountain of excrement not only poses a disposal problem, it also creates a potent source of methane emissions and nitrous oxides — greenhouse gases that are more potent than CO2.

But to Wernick and his colleagues at UCLA, it’s not just a big pile of poop: it’s a really big – and renewable – source of biofuel. What’s the big deal about poop? It’s the protein.

Typically, bacteria look for protein in the environment and then use that to grow.

But Wernick engineers the metabolism of bacteria (Bacillus subtilis) so that instead of just growing on the protein, it takes a portion of it and uses it to produce biofuels.

Poop in; fuel out.

Manure isn’t the only material that can be used in this process. Protein-rich byproducts like wastewater algae and fermentation leftovers from wine and beer production could also work.

Learn more about how they’re turning poop into fuel in the video below:


See Dr. Sahin’s Wondrous Spore-Driven Evaporation Engine

It sounds like a steampunk fantasy, but it is, in fact, a real thing. 

Columbia University bioengineers have built a number of working engines powered by water evaporation and contracting and expanding bacterial spores. The machines represent the first time the humidity that naturally rises from evaporating water has been used as a fuel source.

Biophysicist Ozgur Sahin and his colleagues built evaporation-driven devices that enabled a miniature car to move, a mill to spin, weight to be lifted and an oscillatory engine to power LEDs.

The work is actually a continuation of research we reported on in 2014 to generate electricity and make robot muscles from the force of hydrating and dehydrating microbial spores. But where that study showed only rudimentary lengths of polymer film coated with the spores flexing when in contact with water vapor, the group has now created working machinery using the phenomenon. Learn more and see a video below.

Keep reading

Perhaps not surprisingly, skin, our interface with the world, supports the body’s most diverse population of bacteria. There are at least 1,000 different species found on skin, along with dozens of fungi and other microbes. Most of these bacteria aren’t harmful, and many in fact serve protective functions. These species live among the dead skin cells that make up the outer layer of our skin, defending us from disease while they guard their own turf against other microbes.

One example of this relationship is a strain of the bacterium Bacillus subtilis, which is sometimes found on the skin, which produces bacitracin—a common ingredient in many over-the-counter antibiotic ointments. B. subtilis also releases toxic chemicals to kill fungus, possibly including Trichophyton interdigitale and other species that cause athlete’s foot.

To learn more about your microbiome, visit The Secret World Inside You, open now at the Museum.

Image: © AMNH/B. Peterson

The microbes living on and in your skin enjoy shelter, moisture and the chemical building blocks they need for growth. Their turf is valuable, and they will fight to defend it.

Like most microbes typically found on skin, these bacteria don’t harm us, and they may protect us from treacherous intruders. Here, rod-shaped bacteria called Bacillus subtilis (purple) are locked in battle with a fungus that causes athlete’s foot (green). Like many kinds of bacteria, Bacillus subtilis cells can collect in orderly chains to form biofilms—cooperative communities that may improve self-defense. These rod-shaped cells have formed a blockade and are spewing toxic chemicals—a bold attack on an advancing colony of fungus.

The bacteria shown in this exhibition model, Bacillus subtilis, produce chemicals that kill other bacteria, as well as fungus. One strain releases an antibacterial blend called bacitracin—an ingredient in many over-the-counter antibiotic ointments. Under the right conditions, the population of Bacillus subtilis cells can double in about two hours!

Learn more amazing tales of your microbiome in the exhibition, The Secret World Inside You, open through August 2016. 

A behind-the-scenes Microbiome Monday! 

In the Museum’s exhibition studio, the finishing touches are put on a highly magnified model of human skin cells, upon which rod-shaped bacteria called Bacillus subtilis (shown in purple) are locked in battle with a fungus (green filaments) that causes athlete’s foot. Like most microbes typically found on skin, these Bacillus bacteria don’t harm us, and they may protect us from treacherous intruders.

See the finished model in the new exhibition, The Secret World Inside You, now open!