Filing Iron and Magnetism of Filings
Date: Spring 2012
noticed while filing a steel rod that the filings and tip of the rod become magnetized. Since the rod and file were apparently not magnetized before the process, I wonder what "induced" the magnetism. Orientation with or against Earth's magnetic field seemed to have no measurable effect on production of this result. Any ideas?
Striking iron while in the presence of a magnetic field is well established to induce magnetic orientation. Changing orientation with Earth will not matter because the filing causes both; the strike frees the metal so that the filing jumps and flips to N-S and S-N very quickly. Earth's magnetic field is great enough to induce orientation of the molecules.
In old alchemy times, this was a masterful demonstration of power performed before the ruler of the land to ensure funding of the chemist!
In fact, this method of striking iron to induce the metal to orient is also protocol of the Combat Survival Guides for virtually every branch of service. More than once, this sort of "field prepared" compass has steered a soldier home.
Peter E. Hughes, Ph.D.
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Update: June 2012