The discovery of rocks that attracted certain metals is lost to history. As was the case with electrostatics, Aristotle (384-322 B.C.E.) credited Thales of Miletus (625-545 B.C.E.) with the first scientific discussion of the attractive power of the rock later called lodestone. The word “magnet” comes from the region of Greece where lodestone is found. But the power of lodestone was found by other people around the same time. At the time of Thales’ life an Indian surgeon, Sushrata, used magnets to aid surgery. In the fourth century B.C.E.the Chinese Book of the Devil Valley Master says “Lodestone makes iron come.”

In the eleventh century C.E. the Chinese scientist Shen Kuo wrote about the use of a magnetized needle as a compass in navigation. By the next century the Chinese were known to use a lodestone as a shipboard compass. One hundred years later the British theologian, Alexander Neckham, described the compass and how it could be used to aid navigation. Some people thought that the Pole Star attracted the compass, while others thought that the source was a magnetic island near the north pole. In 1269 the Frenchman Petrus Peregrinus wrote a detailed paper on the properties of magnets. But the most comprehensive and famous work was written by William Gilbert in 1600. Gilbert concluded that Earth was a giant magnet.