Henry Oldenburg wrote to Leeuwenhoek requesting that he examine saliva, chyle, sweat, and sperm

April 24, 1674

Leeuwenhoek mentioned it in his Letter 4 of 1674-06-01. In Letter 5 of 1674-07-06, he examined saliva, chyle, sweat, etc., as Oldenburg had requested.

Leeuwenhoek again mentioned it in his Letter 22 of 1677-11-01 to William Brouncker. We have only the Latin translation of that letter, in which Leeuwenhoek reports his observations of human sperm, as Oldenburg had requested.

The letter was calendared in The Correspondence of Henry Oldenburg vol. X, p. 568.


The manuscript is missing; this letter was never printed.