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最早发明指南针的国家  发帖心情 Post By:2008/8/5 14:53:37

  图片点击可在新窗口打开查看春秋时期,中国劳动人民就在采矿、冶炼中,逐渐认识了磁石。到战国时期,就有人用磁石做成器具来判定方向,当时叫“司商”它是在一个无沿的方盘上放置一只水勺似的磁石,水勺的柄端向南指。到北宋后期(公元11世纪),中国人民创造了人工磁铁,此后又创制了“指南鱼”把用磁钢片制成的“鱼”放在水面上,以此指示方向。后来经过反复研究改进,又把磁钢片改成细小的磁钢针,并使它的尖端成磁北极,末端成为磁南极,这就成了指南针。
 
  北宋杰出的科学家沈括,对于指南针的制作和使用,作了许多科学的说明和分析。到了14世纪初,指南针才由中国传到欧洲。

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