Lens on Leeuwenhoek

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Why we remember Leeuwenhoek today

This linen merchant and civil servant from Delft developed a tiny single-lens microscope that let him become the first human to see the hidden world of microorganisms. His fifty years of letters, many to the Royal Society of London, recorded his observations of protozoa, bacteria, spermatozoa, and red blood cells flowing through capillaries, among many other things.


Antony van Leeuwenhoek
and his "Little Animals"

by Clifford Dobell

First published in 1932, but it has not been surpassed. If you read only one biography, make it Dobell's.

Video Overview

of the life, times, and
accomplishments of
Antony van Leeuwenhoek

(< 8 minutes)

Featured Letter

Letter 28 of April 25, 1679, to Nehemiah Grew

The earliest written of the 165 letters that he self-published. His summary:

Dissections and discoveries of the living little animals in the milt of male seed of fish, and in the testicles of animals. More than ten times as many living animals come from the milt of a cod as there are people living on the Earth. Read more

Featured Figure

Letter 28 Figure:

The testicle of a dog after the second skin had been taken off

Did you know ...?

In the history of the British Royal Society's journal Philosophical Transactions, Leeuwenhoek, with over a hundred articles, is its most frequently published author, by far.

Leeuwenhoek 117
Martin Lister 87
Edmond Halley 81
Robert Boyle 58