The story of Electricity begins many years ago in ancient Greece. It begins with a great philosopher and mathematician named Thales of Miletus, who lived 600 years before the birth of Christ. Thales was a man of great curiosity. His table was always littered with all kinds of objects he liked to examine and study. One afternoon he was working at his table when he noticed a piece of amber. He picked it up and rubbed it on his cloak to make it shine. He rubbed it again, this time harder and then stared. He placed the amber back on the table. Suddenly a small splinter of wood, which had been lying on the table near the amber, moved over to the amber and stuck to it. Thales had seen the splinter move all by itself.
Thales tried it again. He picked up the amber, rubbed it hard on his cloak, and then placed it near the piece of wood. The wood again was attracted to the amber. Thales this time slowly picked up the amber with the piece of wood stuck to it. For several moments he just sat there and gazed at the two objects in his hand. Then Thales wondered: would the amber attract anything besides wood? He tried it and found that bits of cloth, feathers and other light objects acted in the same way as the wood. If the amber was rubbed, the objects were attracted. If the amber was not rubbed, nothing happened.
This mysterious happening needed some thought. What could it mean? While Thales was trying to unravel the mystery, he remembered the legend of a shepherd named Magnes, who wandered endlessly over the countryside, tending his flocks. One day as Magnes was following his sheep up a steep hill; he leaned heavily on his staff as he picked his way over the stony path. Just then he stopped short. He could not move his staff. It was stuck fast to the ground. To his surprise and bewilderment, he found that the iron tip of his staff clung tightly to a large black rock and it took a mighty tug to pull it loose.
Magnes’ trouble was caused by lodestone, a rock that has the strange property of attracting iron. A lodestone is a natural magnet that is found in various parts of the world. It acts exactly the same as man-made magnet. Thales knew about the lodestone. He also knew that magnetite attracted iron without being rubbed. Amber, on the other hand, had to be rubbed before it would attract anything. He wrote down his observations, never for a moment suspecting that he had made one of the great discoveries in the history of electricity.
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