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Greek fire -

During the seventh century, the Byzantine Empire was under attack by invaders from the east of the Mediterranean. Luckily, they had a secret weapon, known as Greek fire, which was sprayed from the safety of Byzantine decks onto enemy ships, propelled by a device that’s never been recreated, but referred to as a “siphon” in ancient literature.

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Greek fire -

The most mind-boggling aspect is that Greek fire could continue to burn, even on water. Scientists still don’t know what it was made out of. After the fall of the Byzantine Empire, the ancient incendiary weapon disappeared, never to be used again.

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Damascus steel -

Many modern knives and swords claim to be made using Damascus steel, but none are truly the same as the Damascus steel of legend. During the Crusades, reports started appearing that documented a superior steel from the Levant that was unbelievably sharp and flexible, and yet still impossible to damage.

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Damascus steel -

It was once described as an alloy that “could slice through a floating handkerchief, bend 90 degrees and flex back with no damage.” To this day, no one has been able to replicate the original recipe.

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Antikythera mechanism -

In 1901, a strange mechanical device was found at the bottom of the Mediterranean Sea. This item is now known as the Antikythera mechanism, and it dates from second-century Greece.

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Antikythera mechanism -

While it is believed to be an astronomical calculation device of some sort, no one knows who built it, or how they built it, considering that technology of a similar complexity wasn’t seen again for nearly a thousand years.

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The first seismoscope -

Zhang Heng’s seismoscope was created in China circa 132. It is thought to be the first machine of its kind, and was able to detect earthquakes with surprising accuracy. The technology used was far ahead of its time, and historians still aren’t sure how this leap was possible.

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The first seismoscope -

Each dragon represents a principal compass direction, and a ball would fall out of one of the dragon’s mouths into the mouth of its corresponding frog, indicating in which direction seismic activity was happening.

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The iron pillar of Delhi -

In Delhi, India, a massive iron pillar stands at 23 ft, 8 in (7.21 m) tall, and has since the fourth century. What makes this particular pillar interesting is that it is completely free of rust, even after more than a millennium of exposure to the elements.

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The iron pillar of Delhi -

Scientists to this day are baffled by the pristine condition of the iron pillar. Some believe its lack of rust is due to the arid climate of Delhi, while others credit the unique mineral composition of the iron used for its construction.

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The aeolipile -

While the Age of Steam wasn’t kicked off by Thomas Newcomen and his steam engine until 1776, an ancient Greek inventor by the name of Heron Alexandrinus invented his own pneumatic steam engine back in the first century CE.

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The aeolipile -

The technology was groundbreaking, but severely underappreciated, and wasn’t put to any practical use at the time. This first steam engine was admittedly very weak, and only produced a minimal amount of torque.

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The Voynich manuscript -

The Voynich manuscript is one of the most mysterious books in history, and has been stumping even the best cryptologists since its discovery in 1912. It has been dated back to the 15th century, but that’s about all that is known for certain about the book.

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The Voynich manuscript -

While no one can say for certain, most experts believe the manuscript originated in Italy during the Renaissance. It’s written in a language that has been proven impossible to decode, and it's filled with seemingly-scientific drawings of flora that are not known to exist in the natural world.

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The Indian flying machines -

There are a number of reports of flying machines dated long before the Wright brothers’ historic flight, but perhaps the oldest to be found so far is in the Rukma Vimana, a ancient Vedic text dating back to 400 BCE in India.

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The Indian flying machines -

The Rukma Vimana, credited to Maharshi Bhardwaj (pictured), contains sketches of these flying machines, as well as detailed instructions on how to fly them, and even how to switch them to solar energy in times of need.

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Lycurgus Cup -

The Lycurgus Cup is thought to have been made during the fourth century, somewhere in the Roman Empire. When the cup was brought to the British Museum of London, the curators there were amazed by its ability to change colors and opacity depending on which direction the light hit it from.

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Lycurgus Cup -

When lit from the front, the cup is a dark red color, but when lit from the back, it glows green. Researchers have since concluded it was made using a primitive form of nanotechnology, but how the ancient Romans developed this technology remains a mystery.

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Ancient atomic warfare -

The Mahabharata is believed to be a non-fictional account of a long and ancient war between two Indian tribal families. Some moments of violence and devastation in the book sound eerily similar to the aftermath of an atomic explosion, claiming millions of lives within days after the use of weapons called astra in the original Sanskrit, which roughly translates to “launchers.”

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Ancient atomic warfare -

This, of course, seems impossible, but when studies were done in the region of India where these battles took place, they found an inexplicably high rate of cancer and birth defects among the ancient denizens. Neither scientists nor historians have been able to shed any light on this mystery.

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Doctor Sushruta -

Sushruta was an Indian doctor from the ninth century who regularly performed surgeries and medical feats that probably seemed like miracles during his time. Many of these accomplishments are recorded in his book, Sushruta Samhita.

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Doctor Sushruta -

Sushruta documents himself performing surgeries that are difficult even by today’s standards, including successful cataract removals, nasal reconstruction, and apparently even successful prosthetic surgeries.

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The Hypogeum of Hal Saflieni -

Underneath the island nation of Malta lies an expansive underground necropolis known as the Hypogeum of Hal Saflieni. Originally discovered in 1902, experts believe it was constructed around 2500 BCE out of limestone.

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The Hypogeum of Hal Saflieni -

One particular room, now known as the oracle chamber, baffles scientists to this day. Any sound made inside this room is amplified nearly 100 times, in a mind-blowing feat of ancient acoustics. Scientists aren’t sure if this was done intentionally due to inexplicably advanced techniques, or was simply a fortunate mistake.

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Roman concrete -

Concrete has long been known to be one of the simplest and most reliable building materials available to us. While one could reasonably assume that the process of mixing concrete has only been improved on over time, it turns out the ancient Romans were much better mixers than we are!

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Roman concrete -

Some Roman concrete structures have lasted for upwards of 2,000 years, sometime even underwater. While scientists have closely studied the composition of the ancient concrete and have founded traces of volcanic ash and the mineral leucite, which they suspect to be the secret ingredients, they still haven’t been able to recreate the material.

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Viking sunstones -

Old Norse stories tell of a magical stone that was indispensable to Viking sailors crossing the treacherous seas. This stone was said to pinpoint with inexplicable accuracy the position of the Sun, even through a prohibitively cloudy sky.

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Viking sunstones -

Scientists today believe these stones to be chunks of Iceland spar, or calcite, which are known to have polarizing effects. But experts haven’t been able to replicate the process of using these stones to locate the Sun.

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Ulfberht swords -

Similar to the Damascus blades of the Middle East, researchers are stumped when it comes to the composition of Northern Europe's ancient Ulfberht swords. These swords were widely used during the Viking era, and were made of a steel so strong and so pure it doesn’t seem to line up with the smelting and metallurgy techniques known to be used at the time.

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Ulfberht swords -

One particular Ulfberht sword (not pictured), discovered in 2014, was inscribed with Arabic lettering, leading some to believe that early trading between the two cultures enabled some of the Damascus techniques to be adopted by the Northern Europeans.

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Roman dodecahedron -

One of ancient Europe’s most enduring mysteries is that of the Roman dodecahedron. They’ve been discovered all around Europe, vary in size, and all date back to between the second and fourth centuries CE.

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Roman dodecahedron -

While their complex shapes and ominous knobs sticking off of each point seem to indicate they must have had a purpose, no such function has been found. Some experts believe that the scientific community is looking for meaning where there is none, and posits they were simply toys for Roman children.

Source: (New Scientist) (Popular Mechanics) (Ancient Origins) (Business Insider)

See also: Unusual inventions throughout history

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