Other ancient books such as Shan Hai Jing, has a similar record. Iron absorption characteristics of the magnet was found long ago, Master Lu's spring and autumn nine volumes of the review: "the Tzu Chi iron, or lead. "At that time called" magnetic "for" CI "them as a mother of children attracts a magnet attracts iron. And that: "stone is the mother of iron, stone, and CI two, a good stone to appeal to his children, not kind of stone cannot be attracted. "Chinese people used to write magnet" kind stone ", is the meaning of love stone.