Henry Siedentopf

Henry Friedrich Wilhelm Siedentopf (22 September 1872 in Bremen – 8 May 1940 in Jena) was a German physicist and pioneer of microscopy.

Biography

Siedentopf worked in Carl Zeiss company from 1899 to 1938. In 1907 he was nominated as the head of the microscopy department.

In 1902 the ultramicroscope was developed by Richard Adolf Zsigmondy (1865–1929) and Henry Siedentopf, working for Carl Zeiss AG. The ultramicroscope was suitable for the determination of small particles and became the most important instrument of colloid research in colloid chemistry. In 1925, Zsigmondy received the Nobel Prize for Chemistry also for this work.

From 1919 till 1940 he was a. o. Professor for microscopy at the University of Jena. He also worked on the development of micro photography and slow motion and fast motion in the cinephotomicrography. In 1908 he invented together with August Köhler the fluorescence microscope. In 1930 he was elected a member of the Leopoldina

Further reading

• Friedrich Stier (2010), "Siedentopf, Henry Friedrich Wilhelm", Neue Deutsche Biographie (in German), vol. 24, Berlin: Duncker & Humblot, pp. 334–335; (full text online)
• Lexikon der Naturwissenschaftler. Berlin 2004.