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Greek fire -

In the seventh century, the Byzantine Empire faced attack by invaders from the eastern Mediterranean. Fortunately they possessed a valuable asset called Greek fire, a substance that could be sprayed from Byzantine decks onto enemy ships. This powerful weapon was propelled by a device known in ancient texts as a "siphon," although its exact mechanism has never been replicated. The secret weapon provided a crucial advantage in Byzantine defensive methods.  

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Greek fire -

The most baffling aspect is that Greek fire could sustain a flame, even on water. Scientists still remain unsure of its composition. Following the decline of the Byzantine Empire, this ancient incendiary weapon vanished without ever being employed again.

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Damascus steel -

Numerous present-day knives and swords declare to be crafted from Damascus steel, although none truly replicate the legendary Damascus steel. Accounts from the time of the Crusades revealed a remarkable steel from the Levant region that possessed unparalleled sharpness and flexibility, while also being impervious to damage. Such exquisite qualities have not been replicated since.

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Steel from Damascus -

The original compounds of this alloy, praised for its ability to cut through a handkerchief, and bend and flex without damage, remain a mystery. 

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Antikythera device -

The Antikythera mechanism, a peculiar mechanical device, was discovered in the Mediterranean Sea in 1901. Its origin can be traced back to ancient Greece in the second century.

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Ancient device -

The purpose and builders of the device are uncertain, though it is thought to be an astronomical calculation tool. Its construction remains a mystery, as the technology required for such complexity was not witnessed again for almost a thousand years. 

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The first seismoscope -

Zhang Heng invented the seismoscope in China around 132 CE. It is believed to be the first device of its kind, accurately detecting earthquakes. The technology employed was remarkably advanced, mystifying historians who are still uncertain about its remarkable capabilities.

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The first seismoscope -

Four dragons symbolize the main compass points, with a ball dropping from one dragon's mouth into the corresponding frog's mouth to indicate the direction of seismic activity.

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The iron pillar of Delhi -

Located in Delhi, India, is an impressive iron pillar that has stood for over a thousand years. Standing at a height of 23 ft, 8 in (7.21 m), this pillar is noteworthy because it remains completely rust-free despite being exposed to the elements since the fourth century.

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The iron pillar of Delhi -

The iron pillar's remarkably preserved state continues to perplex scientists. Some attribute its rust-free condition to Delhi's dry climate, while others credit the iron's distinct mineral composition.

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The aeolipile -

Thomas Newcomen did not initiate  the Age of Steam until 1776, doing so with his steam engine. However, Heron Alexandrinus, an ancient Greek inventor, created his own pneumatic steam engine in the first century CE.

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The aeolipile -

The technology was revolutionary but greatly undervalued, and was not utilized practically at the time. This crude steam engine was admittedly quite sluggish and only generated a small amount of torque.

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The Voynich manuscript -

The Voynich manuscript, discovered in 1912, remains one of history's most enigmatic books. Though it can be traced back to the 15th century, little else is definitively known about this intriguing text. Despite extensive efforts by cryptologists, its secrets have yet to be unraveled.

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The Voynich manuscript -

Experts widely agree that the manuscript is believed to have originated in Italy during the Renaissance, although its exact origins remain uncertain. Written in an undecipherable language, it captivates readers with its numerous scientific drawings depicting unfamiliar flora, which defy the boundaries of the natural world.

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The Indian flying machines -

Numerous accounts exist of flying machines predating the Wright brothers’ memorable flight, but the oldest discovered thus far is mentioned in the Rukma Vimana, an ancient Vedic document from India dating back to 400 BCE.

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The Indian flying machines -

The Rukma Vimana, said to be created by Maharshi Bhardwaj, includes illustrations of these flying devices, along with step-by-step guides on operating them, and instructions on converting their power source to solar energy when required.

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Lycurgus Cup -

The Lycurgus Cup is believed to have been created in the fourth century during the Roman Empire. Upon its arrival at the British Museum of London, the curators were astounded by its remarkable property of altering colors and transparency depending on the angle of light.

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Lycurgus Cup -

The cup appears dark red when illuminated from the front, but emits a green glow when illuminated from the rear. Scholars believe it was created using a basic version of nanotechnology, yet the methods employed by the ancient Romans to achieve this technological feat remain a mystery.

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Ancient atomic battles -

The Mahabharata is thought to be a factual retelling of a lengthy and antiquated conflict between two Indian tribal clans. Certain instances of brutality and destruction depicted in the text bear a striking resemblance to the aftermath of an atomic blast, resulting in the death of millions within a matter of days. These cataclysmic events are attributed to the deployment of weapons known as astra in the original Sanskrit, which can be loosely translated as "launchers."

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Ancient atomic conflicts -

Studies conducted in the region of India where these battles occurred revealed a remarkably high incidence of cancer and birth defects among the ancient inhabitants, though this claim appears quite implausible. The cause behind this puzzling phenomenon remains elusive, as neither scientists nor historians have been able to provide any explanation thus far.

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Doctor Sushruta -

Sushruta, an Indian physician from the 9th century, was known for conducting surgeries and medical interventions that were considered remarkable for his era. His book, 'Sushruta Samhita,' documents a number of these notable achievements.

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Doctor Sushruta -

Sushruta recorded his own performance of surgeries, which remain challenging even by modern standards. These surgeries include effective cataract removals, reconstruction of the nose, and seemingly successful prosthetic surgeries.

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The Hypogeum of Hal Saflieni -

The Hypogeum of Hal Saflieni, located beneath Malta, is an extensive underground necropolis. Discovered in 1902, scholars believe it was built around 2500 BCE using limestone. 

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The Hypogeum of Hal Saflieni -

Scientists are still puzzled by a specific room, referred to as the oracle chamber. Within its confines, any sound created is amplified by nearly 100 times, showcasing the extraordinary ancient acoustics. The scientific community remains uncertain whether this was a deliberate achievement through remarkably advanced techniques or an accidental stroke of luck.

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Roman concrete -

Concrete has been recognized as a reliable and practical building material for a long time. Despite the assumption that the mixing process has continually improved, it appears that the ancient Romans were superior mixers compared to us.

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Roman concrete -

Certain Roman concrete structures have endured for over 2,000 years, even when submerged. Despite researchers diligently examining the makeup of the ancient concrete and discovering residues of volcanic ash and the mineral leucite—believed to be its secret components—they have yet to successfully reproduce the substance.

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Viking sunstones -

According to Old Norse tales, Viking sailors relied on a mystical stone while navigating dangerous waters. This stone had the remarkable ability to precisely locate the Sun's position, even when obscured by thick clouds.

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Viking sunstones -

Scientists currently understand that these stones are likely made of Iceland spar or calcite, which have known polarizing effects. However, experts have not yet succeeded in reproducing the method of using these stones to locate the sun.

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Swords improved -

Researchers are puzzled by the composition of the ancient Ulfberht swords from Northern Europe, much as they are with the Damascus blades from the Middle East. These swords, which were prevalent during the Viking era, were crafted from an exceptionally robust and pure steel that does not align with the known smelting and metallurgy methods of that time. This baffling discrepancy continues to confound experts.

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Ulfberht blades -

In 2014, an Ulfberht sword (not shown) was found with Arabic lettering, suggesting that trade between cultures allowed Northern Europeans to adopt Damascus techniques.

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Roman dodecahedron -

The Roman dodecahedron is a longstanding mystery in ancient Europe. Found throughout the continent, these objects come in different sizes and all originate from the period between the second and fourth centuries CE.

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Roman dodecahedron -

The peculiarly-shaped and mysteriously-protruding knobs on these artifacts have puzzled experts, leading them to speculate about their purpose. However, no conclusive evidence regarding their function has been uncovered. Some specialists argue that the scientific community may be attempting to assign meaning where there is none, suggesting instead that these objects were simply toys used by Roman children.

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

See also: Bizarre inventions throughout history

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