A fragmented ceramic container discovered in Jerusalem may be an early version of a hand grenade that warriors used during the Crusades around 900 years ago, a new study suggests.
The researchers studied fragments of flasks known as sphero-conical vessels — small rounded vessels with a pointed end and an opening at the top. The sphero-conical shape was a common design for ships in the Middle East at the time, the researchers said in a report. demonstration. Containers were used for a wide variety of purposes, including for storing oils, medicines, and mercury, for drinking beer, and more.
In the new study, researchers analyzed chemical remains found in four sphero-conical containers that were discovered at a site called the Armenian Gardens in Jerusalem and date to between the 11th and 12th centuries. two stored scented materials such as perfume or medicine, while the final container was filled with traces of explosive materials – suggesting it was used as a portable explosive device.
This is not the first time researchers have suggested that hand grenades were used during the crusades — a series of religious wars between 1095 and 1291, in which European Christians tried to extend their influence over the Middle East. First-hand accounts of crusader knights and passages of Arabic texts mention the use of handheld devices that exploded with loud noises and a flash of light during conflicts, according to the statement.
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However, many archaeologists have abandoned the idea of sphero-conical containers being used as hand grenades, mainly due to the lack of physical evidence.
“Since the 1980s, the idea that containers were grenades has fallen out of favor as analysis has begun to identify other uses for these vessels,” said lead author Carney Matheson, a molecular archaeologist at Griffith University in Queensland, Australia. , to Live Science. But researchers in the new study remained open to the possibility that these containers could be used as portable explosives, he added.
Portable explosives require three essential components; a fuel to burn, an oxidizer to help ignite the fuel, and a container that applies pressure, allowing the reaction between the fuel and the oxidant to build up in pressure until it causes an explosion, Matheson said.
The grenade-like container the researchers analyzed had much thicker walls than the other ceramics studied and showed signs of being sealed with resin, indicating that it is well suited to maintaining the pressure necessary for an explosion to occur. However, to confirm that the vial was used as a grenade, the team also had to provide evidence of explosive materials inside.
Previously, researchers thought that the first portable explosive devices likely contained black powder, also known as gunpowder, which uses coal as a fuel and potassium nitrate as an oxidizer. Black powder was invented in ancient China, but it wasn’t introduced to the Middle East until the 13th century, which was after the ship was made.
“One thought was that there may have been an earlier arrival of this black powder technology that was kept secret,” Matheson said. But analysis showed that there was no trace of black powder on the vessel.
Instead, the researchers found that the fuel used in the explosives was a mixture of vegetable oils and animal fats, and the oxidant was a mixture of nitrates, including sodium nitrate, calcium nitrate, potassium nitrate and magnesium nitrate. The team also found traces of sulfur, which was likely added to reduce the temperature necessary for the explosive reaction to occur.
The researchers suspect that similar grenades contained additional ingredients that would have altered the explosive characteristics, such as magnesium, which could have produced the bright flashes mentioned by witnesses, Matheson said.
However, it is unclear exactly how the explosive materials would have been ignited. “The ingredients could have detonated on impact, but we’re not sure,” Matheson said. The team suspects the warriors placed a fuse inside a small crack found in the container that had been held in place by resin, he added.
The new discovery highlights the diversity of ancient pottery in terms of design and purpose. “They [similar containers at the time] are classified as sphero-conical vessels based on their shape,” Matheson said. “But their fabrication, size, decoration and wall thickness vary enormously.”
Containers were also likely highly specialized, Matheson said. “I don’t think the type we identified as a grenade was used for anything other than an explosive weapon.”
The researchers want to study similar containers found across the region to find out how common the explosives were, but suspect the grenades were less rare than people realize. “There are many garnet-like ceramic fragments found throughout the Middle East, so their number is likely very high,” Matheson said.
The study was published online April 25 in the journal PLOS One.
Originally published on Live Science.