ABSTRACT
Among the rather widespread and fairly abundant minerals found on Earth is a crystalline mineral ore of iron called magnetite, which, unlike any other iron ore, is magnetic. Occasionally, pieces of this ore, called lodestones, are found which are permanently magnetized. Some specimens have been known to have such a strong magnetization as to lift several times their weight. There is good reason to believe that the attractive power of lodestone has been known to mankind as early as 5000 years ago. It is said that Huang-ti, “an emperor of China in the year 2637 BC, had a chariot, upon which was mounted the figure of a woman, pivoted or suspended so that it was free to turn in any direction. The outstretched arm of the statue always pointed to the south under the influence of concealed lodestones” [Mey 71, p. 2].
