Friedrich Miescher discovers a weak acid in the nuclei of white blood cells that today we call DNA

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14 February 1869 Birth of Charles Thomson Rees Wilson

9 April 1869 Birth of Élie Joseph Cartan

13 May 1869, Birth of Ferdinand Ellerman in Centralia, Illinois, USA

4 October 1869, Birth of Maurice Anderson Ainslie in Corfe, Somerset, England

30 November 1869 Birth of Nils Gustaf Dalén

1869 Birth of Fritz Pregl

1869 Death of Johannes Purkinje

Chronology 1868 - 1869 - 1870