Ancient Greek Technology

When most people talk about ancient Greek civilization, they usually think about the humanities (philosophy and literature) that flourished in ancient Greece. They know Plato and his theories about the ideal forms, they admire the depth of Aristotle's thought. However, few people heard about the contribution of the Ancient Greeks in other sciences like medicine, which was made by Hippocrates, or mathematics and geometry by Pythagoras, Euclid and Archimedes and fewer know about technological achievements of the Ancient Greeks.

Among these achievements we can find automatic doors, steam engine, air and water pumps, gears, astrolabes and clocks. The work principle of some of these inventions is still used nowadays. So in this work I want to describe some inventions of the Ancient Greeks and to find out why technology didn't develop further, what the reasons were.

Unfortunately, all original Greek texts were destroyed. So when we talk about Greek texts actually we mean Byzantine copies and copies of Arabs, who translated the originals and extended them in their own researches. Thus many scientific works, investigations and inventions did not reach us.

Ancient technology served for religion. When a believer presented gifts to a God, the God should thank him. Otherwise, the believer would go to another God (they had polytheism at that time, polytheism means a lot of Gods). In such way some priests could loose people who come and give presents to the God. And today everybody knows that these gifts were taken by priests for their own use. Thus today church is one of the richest organizations. So to keep believers priests widely used technology. For example: in some temples certain doors opened automatically when the fire was lit on the altar (pic.1) and even certain statues began moving.

"It is said that Heron Ð'... had constructed mechanisms that sounded the trumpets of a temple when the altars were lit. The interior of temple was sprayed with scented water, metallic birds began singing and some statues began flying. It is also said that the lighting conditions in and around the temple were regulated, creating artificial fog, when necessary".

Heron was a Greek mathematician, engineer and inventor of the first century BC. He lived in Alexandria and worked as shoemaker. He is better known as an inventor of the hydraulic mechanisms. Heron was also a good mathematician. He wrote a book called "Metrika", which included different mathematical formulas.

He built the world's first steam engine (pic.2) . This steam engine consisted of a closed, spherical container, filled with water. When the water was heated and began to boil, the stream was released by two nozzles which were installed in a polar alignment. The container was made so that it could rotate and the steam release caused a rotating motion of the container that could be used as a steam engine for various applications. This invention used the Newton's Third Law of motion: "Every action produces a reaction equal in force and opposite in direction". But Heron didn't know that.

Ctesibius of Alexandria was a Greek physicist and inventor living around 285 Ð'- 222 BC. Unfortunately, we have little information about his life and his work. When he was a young boy, he dropped a lead ball in a tube and, when the air escaped, there was a loud sound because the ball compressed the air. Owing to this fact Ctesibius understood that air was also a substance, so his inventions were based on this fact.

Ctesibius invented the Ð''clepsydra', which means water thieve, or water clock (pic.3) . He used three containers. One of the containers was used to keep another container always at the same level. This was made by applying a float with valve. When the level of the water fell below, the float with valve went down and the water from the above container began to fill the second container. Then the water flowed into the third container and the level of the water in this container showed the time for example using a floater with a pointer on a calibrated time scale. Ctesibius wanted to transform the Ð''clepsydra' so, that it didn't indicate the end of a given time, but it could work continuously. He noticed that the water from the second container flowed into the third container faster when the jar was full and slower as it emptied. Therefore Ð''clepsydra' couldn't display time appropriately. So his very simple solution was to keep the jar always full. He added one more container with a bigger hole. The water from this container dripped faster and so Ð''clepsydra' remained full. Thus Ctesibius provided Ð''clepsydra' with water flow of constant rate. Such Ð''clepsydra' that never emptied was of no value. But Ctesibius managed to find a way to measure the water that came out. A solution was again a float with a pointer in a third container. As the water level rises in the container, the float goes up. The float is connected to a stick with notches. When the float goes up, the stick goes up too. At this moment notches turn a gear, which moves the hand that points to the time. "In the 16th century AD the clepsydra was used by Galileo to time his experimental falling objects. This invention is similar to the mechanism used in the modern flush toilet. The floating valve is the predecessor of the floating ball in the upper chamber of the toilet. After a flush, the floating ball sinks with the declining water level, pulling open the water valve with its metal arm. The incoming water fills the vessel again, raising the ball so that its arm closes the flow of water at the full level" .

Ctesibius built a water organ (pic.4) , which consisted of an air pump with valves on the bottom, a container with water and a row of pipes on top.

Ctesibius invented a water pump to fight with fire. But, ironically, this invention was lost and forgotten in the burning of the home city of Ctesibius, Alexandria. Firemen were the bucket brigade, which presented two lines of people connecting the water source and the fire. One line passed full buckets, the other returned empty buckets. "By the eighteenth century the principle behind the Ctesibius pump had been rediscovered and hand-operated fire engines began making their appearance" .

The great mathematician, Pythagoras (lived in the 6th century BC), believed that everything in the world could be turned into numbers and he found out the relationship between the mathematics and the music. This made the making of musical instruments much easier. For example: the sound of strings depended on their length.

Archimedes lived in the 3rd century BC. He was great mathematician and physicist. He found out how to calculate