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> The orientation of ancient Greeks Issue: 2006-1 Section: Math

Greek

 

Introduction

Ships

Depictions of ships with Psaraki in their bow from protocycladic frying pans.

(3rd millennium B.C.)

From 8000 B.C. till the end of the Hellenistic era, the Greeks developed their nautical skills to a high level, so they had been dominating in Mediterranean for centuries. But the main question coming up is how the Ancient Greeks were oriented? How did they find the latitude and the longitude of a certain region? How did they find their route? For this purpose different instruments were used, i.e. a kind of compass, sundials, the polometer or even some constellations.

 

Pyxis (pyxida)-psaraki

Nowadays, it is well known that the basic instrument of sailing is the pyxis (compass). Did Ancient Greeks have a similar device? Which people used it first? It has been proved that the only people who have used this compass beyond Europe were the Arabs and Chinese.

 

The compass was a clay, stone or metal disc in which the four points of horizon were designated. A magnetic stone showed the South and later the North. The first important information about the use of an iron fish as a compass (pyxis-psaraki), is referred to by the Chinese at about 1044 A.D. Nevertheless, a verified use of a ship compass appeared when China was the biggest marine force of the world at around 1000-1300 A.D. On the other hand, the texts referred to the use of the fish-compass by Arabs are dated to 1200 A.D.

 

The fish found on the bow of the prehistoric ship from Cyclades pointing to the south, was actually a compass made from magnetic stone. The same fish was incised on some strange clay artifacts (known as frying pans), found in Cycladic tombs, which are dated to the protocycladic period at ca. 2800-2300 B.C.

 

The sundial of Philippi

Another instrument for orientation is the sundial. One of the most remarkable sundials has been found at Philippi, region of Macedonia. It consists of an outermost device, ring shaped, that supports three inner rings. The third ring (the outer one) carries a view hole aiming at the sun. The second ring is made of two half rings where the names of cities, months and other measurements are engraved, from the center to the edges.

 

Polometer or kanal

An instrument that has lost its use through ages is the Polometer or kanal. According to captain Koletis, this instrument had been invented in antiquity and helped the Greek shipmen and explorers in their travels. The information about it is derived from Greek transcripts translated in Arabian. It consists of a rectangular board, 25 cm in length and 15 cm in width. A small semicircular opening is located in the middle of one of the small sides of the board. Below the opening at about 8 cm, a small hole exists through which a packthread is passing. The instrument can be used only on cloudless nights. The observer holds it, with his left hand, in that way he can see through the semicircular opening the Polar Star, while the other small side touches the horizon. At that position, he pulls the packthread to touch the tip of his nose. At this point he carefully makes a knot. Depending on the route of the ship, the knot does not always touch the observer’s nose. When the distance of the nose gets shorter, then the ship is in a more northerly position compared to its original route. In case of longer distance, the ship deviates to the South. Taking the above into account, an experienced captain would be able to correct the ship’s route.

 

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