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David Tomasko, age 10, of Bridgeport, Conn., for is question:

How are magnets made?

Small magnets are doing all sorts of jobs in the kitchen. They are sown into pot holders and built into racks for holding knives and other steel kitchen tools. What they do is cling to metal. A magnetized pot holder will cling to the side of the refrigerator or any other steel surface. A magnetized rack will hold steel tools without the bother of hooks or slots. But these magnets do not keep their magic forever. They tend to turn back into ordinary iron bars. Then their power fades, you can give them a new lease on life.

The first magnets were made by nature. The Greeks and Romans found them scattered on the ground. The strange, dark stones clung to iron clad handles and the iron tips of the shepherd’s crooks. People soon found that the magic power was catching. When a bit of man‑made iron was stroked on a natural magnet, it too became magnetized. You can still use that trick to put now magic into a worn out magnet bar.

Another trick is done with a hammer and a compass ‑ which is really a sliver of magnet. Place the plain iron bar in a line with the compass noodle and give it a few wacks with a hammer, This trick works with a bar magnet and a plain bar of iron. Line them up with one end of the iron bar touching the north pole of the magnet and whack. In either case, the plain iron bar will catch the magic of magnetism.

It will pick up pins and cling to a metal surface. It has a north pole and a south pole. Test it with another magnet. Place them end to end. The two north poles will repel each other and spring apart. A north pole and a south pole will attract each other and cling together. Dangle your new magnet on a string and it will swing around so that its north seeking pole points north,

Any bit of iron can be magnetized ‑ and unmagnetized. The magic disappears when the iron is heated red hot. Blows and bumps also weaken the power. It is even possible to make a magnet that turns on and off. For this useful trick, a wire carrying electric current is wound around a plain iron bar. Huge electromagnets are made in this way. `The powerful magic works when the current is on and stops when the current is turned off. A giant electromagnet can pick up a load of steel scrap, move it to where it is needed and drop it when the current is switched off.

Iron is the best metal for making magnets. Nickel can be slightly magnetic but gold, lead, sine and silver will have nothing to do with th;; magic. It is believed that magnetism is made by the tiny molecules of which the iron is made. Each tiny molecule is thought to be a magnet in its own right, complete with north and south pole. In plain iron, they face this way and that and so cancel out each others magic. A strong jolt may line them up, all facing the same way. In that way, their magic pulling power is all pulling in the same direction. This happens when they feel the power of a nearby magnet.

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