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      Knowledge is Power

      Scientific American December 21, 1912

      Why a Plane "Iron" has a "Cap"

      • By W. D. Graves on December 21, 1912

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      More in the December 21, 1912 issue of Scientific American
      • Correspondance - December 21, 19
      • Steady Rests for Small Lathes
      • Sending Photographs Over a Telephone Wire
      View Full Contents
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