A piece of medieval wisdom

10 medieval inventions that changed the Western world

The idea that the Middle Ages were a time of ignorance and technological stagnation is widespread, but nothing could be further from the truth, especially considering that the medieval period lasted nearly 10 centuries.

Although the first few centuries of the medieval period were marked by chaos due to the collapse of the Western Roman Empire and the birth of new nations, many technological advances during the Middle Ages contributed to shaping the modern world.

Humanity has been trying to measure time since the beginning of history. Ancient civilizations developed several types of clocks—some more accurate than others—such as sundials, hourglasses, and water clocks.

Fully mechanical clocks appeared in the 13th century, usually installed in church towers, and were equipped with bells to announce the passing of hours. More advanced versions also featured hands to display the time.

Growing the same crop repeatedly on the same plot of land leads to the soil losing nutrients and becoming unproductive. Farmers were aware of this and had been using crop rotation in a two-field system since antiquity: they would sow half of the land and leave the other half to rest. The following year, the roles would be reversed, ensuring the soil remained fertile.

In the 8th century, medieval farmers started dividing the land into three parts: one was planted with winter crops (sown in the fall), another with spring crops such as legumes, and the third was left to rest. This new method not only increased the harvest, but the greater diversity of crops improved overall nutrition due to the greater diversity of food.

There are records of visual aids used in ancient Rome and Greece, often made from precious stones like emeralds, and Arabic sources describe the use of magnifying glasses. However, the first pair of eyeglasses was developed in Italy in the mid-13th century. These early glasses had convex lenses, meaning they were only useful for farsighted individuals. Glasses with concave lenses, suitable for nearsightedness, would not be developed until the 15th century.

The existence of prestigious learning centers in antiquity is well documented, but universities as we know them are a medieval development. In the chaos of the early Middle Ages, Christian monasteries preserved and transmitted classical knowledge, becoming centers of education and research.

The University of Bologna, founded in 1088, is considered the first institution to be academically independent and to award higher education degrees to both clergy and laypeople.

While humans had already been using grindstones to sharpen knives and weapons for centuries, they used a static stone, which required a significant effort for the person doing the sharpening.

The earliest known record of a rotating grindstone machine operated by a lever dates to the 8th century. By the 14th century, a pedal-and-crank mechanism had been incorporated, allowing for better control of the speed and making the sharpening process much easier.

Ancient mariners and travelers used the stars and other natural landmarks to determine their geographic position, but this method depended on good weather and clear skies. By the 13th century, some records describe sailors using a magnetized needle floating in water to point north.

The modern, round compass is often attributed to the Italian sailor Flavio Gioia in the early 14th century. He is said to have combined the floating needle with a wind rose and encased it in a box, making it portable, reliable, and easy to use.

Many people believe Gutenberg to be the inventor of the printing press, but woodblock printing dates back to ancient China, and the screw press had already been introduced by the Romans in the 1st century. By Gutenberg’s time, paper presses were widely used in Europe, but what was groundbreaking were the changes he introduced to the printing process.

Gutenberg modified the basic paper press to mechanize it and ensure even pressure across the paper surface. He also developed a system of movable type, which allowed the press to reproduce any text at a higher speed. He is also credited with the development of an oil-based ink, more suitable for paper printing than the traditional water-based ink.

The ancient Greeks and Romans developed central heating systems that relied on hot air traveling through pipes, but these systems disappeared after the fall of the Roman Empire. During the medieval period, Christian monks living in the Alps developed a new system that used underfloor channels to carry heat from a furnace. By the 13th century, monasteries in Spain started using water to carry heat, in the same way that some of the modern heating systems do.

Although the Romans had created industrial chimneys for their bakeries, true domestic chimneys and fireplaces were developed in the Middle Ages to allow people to cook indoors and heat their homes safely. These early chimneys were wider than modern chimneys to allow more heat to remain in the room, and had a cap to cover the chimney top in case of downdrafts. Though it’s worth noting that domestic chimneys became more common around the 12th–13th centuries in Europe.

Fire has long been used as a weapon during wars, especially to burn down fortresses and ships. However, fire can be easily countered with water or other fire-retardant materials.

In the 7th century, during the Muslim sieges of Constantinople, the Byzantines reportedly used an incendiary weapon developed by an architect named Callinicus. This formula produced a substance that could burn even on water, helping the Byzantines repel the enemy navy. Greek fire is considered a precursor to modern incendiary weapons, influencing the development of devices like the hand grenade.

UNSOLVED PUZZLES

10 baffling natural phenomena we still don't fully understand

Image: Stormseeker

We have certainly come a long way since the first humans began wondering about the nature of the universe. But even with significant technological and scientific progress behind us, some phenomena remain elusive, even to experts. These unsolved mysteries continue to baffle researchers, often hinting at how much we still have to learn about the universe. So, jump aboard and join us on this journey through some of nature’s most intriguing mysteries, from dark matter to the reasons behind why we yawn!

Image: arnaud girault

You might think this is a rather dumb question, but its answer is something that keeps many scientists awake at night. The fact is that, according to the best calculations, the universe is missing a lot of mass. And by a lot, we mean A LOT—up to 85% of the total mass we can estimate from gravitational effects is nowhere to be found.

This has led scientists to posit the existence of an invisible form of mass that could account for many otherwise unexplained cosmic phenomena (such as the acceleration of the universe’s expansion), fittingly called "dark matter." Undetectable by most conventional means, recent experiments have allowed scientists to explore this mystery further. Some speculate that dark matter could consist of a new type of subatomic particle or even millions of minuscule primordial black holes.

Image: Jr Korpa

Dreaming seems like such a natural and commonplace phenomenon that we rarely question why we do it. The nature of dreams has fascinated humans since ancient times, with beliefs about their causes varying widely across cultures and centuries. But despite recent advancements in neuroscience and related studies of the human brain during sleep, both the purpose and precise origin of dreams remain unknown.

So far, we only know with certainty that dreams primarily occur during the rapid eye movement (REM) stage of sleep. During this stage, brain activity is surprisingly high, resembling a state of wakefulness. Some theories propose that dreams help process emotions, solve problems, or even simulate threats, but their true function remains one of neuroscience's greatest mysteries.

Image: Amos

Sometimes, during thunderstorms, people have observed a baffling phenomenon: ball lightning. These are luminescent, spherical objects that seem to fly erratically over the ground, only to suddenly disappear without a trace. This rare and elusive weather phenomenon has been reported since the 19th century, and it has been suggested as the origin of many ancient myths and legends.

While scientists have yet to determine its exact origin, there have been advances in experimentally reproducing the phenomenon through various methods. Hypotheses range from the vaporization of silica in the soil by lightning strikes to the disturbing possibility that ball lightning is entirely a product of lightning-induced hallucinations in the observers' minds.

Image: Lamna The Shark

Are we alone in the universe? So far, the search for extraterrestrial life has not yielded any significant results, though some recent findings have excited scientists about the possibilities. Traces of chemicals often associated with biological processes have been detected in Venus’ upper atmosphere, hinting at the possibility of extraterrestrial microorganisms being present in the planet’s clouds. However, further research is needed to confirm these findings.

Also, there is the still largely unexplained "Wow! Signal," a mysterious radio signal picked up by the Ohio State University's Big Ear radio telescope in August 1977, which some researchers have suggested could be a sign of intelligent life. The signal appeared to come from the direction of the constellation Sagittarius, but it has not been detected again since.

Image: James Yarema

A very well-documented phenomenon, to the point where it is essential to account for its effects in randomized clinical trials to test the efficacy of various medical treatments, the placebo effect remains largely a mystery to science. How can a sugar pill or an inert saline injection produce real, measurable health benefits instead of doing nothing at all?

Most hypotheses point to psychological mechanisms at play, where the belief in treatment activates the body's natural processes for relieving pain and other symptoms. This "ritual effect" could influence the individual's expectations, preparing them to feel better.

Image: Dmitrii Shirnin

In 1908, an extremely violent explosion seemingly out of nowhere flattened over 80 million trees in a vast forest area in Siberia. With an estimated force of 3 to 50 megatons (for comparison, a modern nuclear weapon yields just over 1 megaton), the explosion left no distinguishable impact crater, suggesting that it occurred above the ground.

So far, the leading explanation for the event is a meteor airburst—an explosion of a large rocky asteroid entering the atmosphere at an altitude of 3 to 6 miles. Despite the area being very sparsely populated, eyewitness accounts report observing a bluish light moving across the sky before the time of the explosion, supporting the meteor hypothesis. The sudden burst of energy was reportedly so strong that its shockwave knocked people off their feet and broke windows hundreds of miles away.

Image: Adrian Lange

The origin of life on Earth, known as abiogenesis, remains a mystery. Various theories exist, from life emerging through almost spontaneous chemical reactions in a primordial soup to the idea of panspermia, which suggests that life could have originated elsewhere in the universe and been brought to Earth by meteorites.

The prevailing hypothesis, however, is that life did not originate from a single event but rather through a complex process involving many stages. Connected to this mystery is the question of whether life can exist in forms different from those we know, potentially using elements other than carbon and water.

Image: NASA/JPL-Caltech/Space Science Institute

Saturn's north pole is home to a giant hexagon-shaped storm, a phenomenon unlike anything else seen in the solar system. This strange phenomenon was first discovered during the Voyager mission in 1981 and was later revisited by the Cassini-Huygens probe in 2006. Curiously, the hexagon seems to change colors over time, exhibiting variations from bluish to golden hues.

Some of the most compelling hypotheses point to complex atmospheric dynamics, such as wind patterns and pressure variations, as potential culprits for the storm’s bafflingly geometric shape. Experimental tests have managed to recreate similar patterns under laboratory conditions, but it remains uncertain whether these processes mirror those observed on Saturn.

Image: Clay Banks

Star jelly is a mysterious, transparent gelatinous substance occasionally found on the ground or on tree branches. Since ancient times, its appearance has been linked to meteor showers and similar celestial phenomena. Theories about its origin vary widely, ranging from unfertilized frog spawn or even frog vomit to different species of slime mold or algae colonies.

However, no scientific consensus has been reached, and its true origin and nature remain unknown. Scientists have yet to conclusively determine where star jelly comes from.

Image: Miikka Luotio

If this article has got you yawning (we hope not!), you’re encountering one of life’s many unexplained mysteries right under your nose! Yawning is a universal human experience, yet its purpose remains unclear. Various theories suggest that yawning might help cool the brain, increase alertness, or even serve a social function, but no single explanation has been universally accepted.

Curiously, yawning is not limited to humans; it occurs in almost all vertebrate animals, including mammals, birds, reptiles, amphibians, and even fish!