. For about thirteen hundred years after Lucretius, scholars insisted that certain magnets possessed the property of attraction while others possessed the property of repulsion. To their minds, it did not seem possible that the same magnet could both attract and repel other magnets. Gradually it became evident that the two ends, or poles of a magnet are unlike in certain respects. Roger Bacon (1210-1294), an English philosopher and scientist pointed out that magnets could repel as well as attract other magnets.In 1600, William Gilbert, an English doctor, proposed that the earth was like a giant magnet. He had been experimenting with round pieces of magnetite and magnetized needles when he realized that the magnetite was attracting the needles in a way similar to the earths attraction of a compass needle. William Gilbert was also the first to call the ends of the magnets poles.William Gilbert's idea that the earth is a giant magnet turned out to be basically true. The earth is thought to obtain its magnetism from electricity made by molten iron and nickel sliding around inside it. The Earths magnetism is centered at an area in northeastern Canada by the North Pole (another center is by the South Pole). The needle of a compass points not to the top of the earth but to the magnetic north pole off to the side. The ends of a magnet are named after the north and south poles of the earth. The actual words north and south are just handy names a scientist gave the different ends long ago so he could talk to people about them.Scientists idea of what causes magnetism can best be explained by first saying that all things are made up of tiny particles called atoms. If you could look at the atoms in a piece of iron, which is what is used to make magnets, you would see that they are made up of even smaller particles. Atoms have a nucleus, which is made up of particles called protons and neutrons. Charged particles called electrons move a...
