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HARPER’S LIBRARY _of_ LIVING THOUGHT

[Illustration: (publisher colophon)]




[Illustration:

  DIAMONDS

  BY
  SIR WILLIAM
  CROOKES

  HARPER &
  BROTHERS
  LONDON & NEW YORK]


[Illustration: THE CULLINAN DIAMOND.

From a photograph by the Author. (See pages 76-79.)

  Frontispiece.]




  ·DIAMONDS·


  BY

  SIR WILLIAM CROOKES
  LL.D., D.Sc., F.R.S.

  Foreign Sec. R.S