A mysterious black mineral, which attracted iron, was most probably known thousands of years ago. In a Greek myth its discovery is ascribed to an unknown shepherd Magnés. When he stepped on this mineral, the nails from his boots and the point of his stick stayed in the earth. Also a Greek scholar Thales from Milét, who lived in 6^th century B.C., knew this mineral. The Greeks learned about this mineral with extraordinary qualities during the colonisation of the Front Asia, there it freely appeared in certain localities (today’s western part of Turkey). They called it magnés, but rather according to the place of discovery, than to the shepherd.

Those days even the Chinese people knew this mineral. They noticed, that if the stone has got the right shape (rod like) and the possibility of free motion, it always keeps the same orientation. And so the first primitive compasses arose. But they were used only for the Chinese art called Feng Shui. Its adherents believe, that the orientation of furniture, buildings and graves according to the compass, can harmonize their life with ”a cosmic breath”.

Today we know, that the ”mysterious black mineral” was nothing less than the most substantial iron ore (it contains up to 70 % of iron) known as lodestone (magnetite). In Czechia it partly appears near the area of Kutna Hora).

In the 11^th century the Chinese people innovated the compass by creating so called swimming or water compass. Its construction was following: They placed a wooden float in a bowl with water; then they fixed a magnetite of rod like shape on it. The qualities of this innovated compass allowed to take advantage of it in the ships´ navigation – instead of the Sun, Moon or Pole-Star.

Hundred years later these compasses were used on European ships. Later they found out, that the magnetite can be replaced with a steel needle, which was magnetized with rubbing it against he magnetite.

The orientation of ships according to the compass allowed the seafarers to set out on more advantageous sailing. Compass was an inevitable helper of Christopher Columbus on his revealing journeys to America. During them he found out, that the Pole-Star, which was considered to be a ”fixed point” in the north, is not exactly in the north and it rotates in the sky just like other stars.

Pocket compass

Today the simple pocket size compasses have the magnetic needle fixed to a pin in the middle of the rosette. Bigger compasses have two or ore needles fixed to the lower side of the rosette, which turns round (this construction was used by Columbus).

Odchylka mezi magnetickými a zeměpisnými póly Zeme (deklinace)