Greek Fire

Greek fire was a weapon used in 678, by the Byzantine empire in a naval battle to fend off an Arab fleet from Constantinople (modern day Istanbul, Turkey), and was used many times after, all the way up to the 14th century. According to Britannica, "It was invented during the reign of Constantine IV Pogonatus (668–685) by Callinicus of Heliopolis" (Micheal Ray, Greek fire, 2015). It is an incendiary substance that was sprayed out of tubes and thrown in grenades. The thing that made it different was its ability to burn on water. People today have tried to recreate it, but it's formula was heavily guarded so that no one could use it against the Byzantines themselves. Scientists believed it likely included, petroleum, quicklime (a white powder substance), and sulfur.

Archimedes Claw

The Archimedes Claw was a defense mechanism used by the city of Syracuse, from 214-212 BCE. It's been told it played a role in delaying the Romans conquest on Syracuse for several years. Explorable says, "some of these dropped huge weights , punching holes through the ships and sinking them. Others had a claw or grappling hook, which grabbed hold of the rigging or rails of a galley, raising it, shaking it and capsizing it" (Martyn Shuttleworth, War Machines of Archimedes, Sep 2, 2011). This invention is not used anymore because we have developed missiles and other more effective naval defenses, ships have also become too heavy to be lifted with a hook.

Water Clock

The water clock was a way to tell time, used around the 5th century BCE, based on the passage of water. Hellenic.org states, "The clepsydra, or ‘water thief’ is a bowl-like vessel with a hole at its base, which is sized to create a non-stop pressured water flow" (Hellenic Museum, Water Clocks and Whistling Wakeups, Oct 7, 2022). Earlier versions had notches built into the bowl to show what time it is based on what notch was visible. Shortly after it's invention, a Greek engineer, Ctesibius, made a design of the water clock that was so well designed, it was claimed to be "the most accurate time keeping instrument" for the next two thousand years. It was only dethroned when physicist Christiaan Huygends invented the pendulum clock, in the year 1656. Later versions of the water clock even had a whistle that would sound off when air in chamber became compressed enough, making it the first alarm clock. People stopped using the water clock around when the pendulum clock was invented, because it was more accurate, and newer technologies with electricity are cheaper and way smaller.

Clay Bullae

A clay bulla (plural, bullae) was used in the ancient middle east around 8000 to 3100 BCE. They were hollow clay balls that would hold tokens representing the type and quantities of goods being traded. They were put in clay balls so that they couldn't be tampered with unless they broke the clay ball. These spheres required skill to make, which made them a very early form of specialization. These were created because in somewhere from 8000 to 7500 BCE, Sumerian farmers needed to keep record of their crops and livestock. They kept track using clay tokens they formed with their hands. Wikipedia says, "Around 3100 BC signs expressing numerical value began to appear. At this point, clay tokens became obsolete." (Wikipedia, Clay Bullae, Feb 9 2025)

Roman Hypocaust System

The Roman hypocaust was an area about 8 inches tall beneath the floor of a building, which was heated by a fire connected to it by a passage or tunnel. This was to warm the floor of the house or building above the hypocaust. It would also often have a tunnel going into the wall of the room to direct warm air and smoke into the room. Brittanica remarked, "Piers approximately 8 inches (20 cm) square and about 2 feet apart were used as the supports for the hypocaust’s internal space" (Brittanica, hypocaust, Aug 10 2016). These systems have become outdated by electrical heating systems that are easily expanded to reach more areas, don't require less sturdy floors to be used, and aren't fueled by a flame so you don't have to tend to a fire.

Chalked Invention Archive

CIA

Greek Fire

Archimedes Claw

Water Clock

Clay Bullae

Roman Hypocaust System

Work Cited

Chalked Invention Archive

*CIA*

Greek Fire

Archimedes Claw

Water Clock

Clay Bullae

Roman Hypocaust System

Work Cited

CIA