In the previous story, we read how the magnet was accidentally discovered when Magnes, a shepherd, found out that a piece of dark rock in Magnesia (northern Greece) pulled the nails off his shoes. The stone was called lodestone, and the magnet became a household item. Many people regarded it as a remedy for varied types of diseases. It was also regarded as an object of charm and luck to ward off evil spirits. As its demand increased, many traders went to Magnesia to fetch the magic stone. They cut it neatly into rectangular bars and sold them at high rates.
Most sailors used to carry magnets during their voyages for safe sailing. They would hang a piece of magnet in their ship for 
divine protection from storms and bad weather. Once, a sailor noticed that one end of the bar magnet, which was hung in his ship, was pointing towards his left as he stood facing the rising sun. One corner of that end was slightly chipped off.
Then the captain ordered that the ship be turned right. The sheep steered neatly ninety degrees to the right. After a few minutes, the sailor casually glanced at the magnet bar, and he was astonished to see that the end with a chipped corner was still pointing to his left when he faced the rising sun.
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“If the ship has turned, then the bar must have turned too,” he argued. He lazily turned the hanging magnet to point the end towards the rising sun, but the bar twirled back into its original position. He tried again and again, but no matter in which direction he set it, it would turn back and orient itself into its initial bearings.
He called the captain and other sailors and they were all amazed. They all tried to place the magnet in different ways, but the magic bar restored itself to its NORTH – SOUTH position.
The captain marked the ends N and S to represent North and South. He told the sailors to monitor the bar carefully throughout the voyage. The ship turned this way and that, sometimes sailing East, sometime South, and yet the bar always kept to its N - S direction.
When the sailors returned home, they announced the monumental discovery. People tested it and it was found true – no matter how you turn a magnet, it would finally come to rest with its bearings: one end pointing North, the other end directed towards South.
They decided to call it North Pole and South Pole. Now carrying a magnet became even more important: not just superstitious belief - it had a practical utility. It could always give the direction, and it was no longer necessary to depend on the sun or stars.
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