Robert Hooke wrote Letter L-063 to Leeuwenhoek to acknowledge the receipt of Letter L-060 of November 1677 to describing sperm in human semen

Date: 
December 10, 1677

This letter is known only by reference in another letter.

The date is New Style, which was ten days ahead of the Old Style date of 30 November used by Hooke in London.

In this letter, Robert Hooke acknowledges the receipt of Leeuwenhoek's Letter L-060 of November 1677 to William Brouncker describing sperm in human semen.

Document: 

Letter 37 [23] L-067 of 14 January 1678 to Robert Hooke:

Yours of the thirtieth of November I received not till January 8th, whereby understanding the kind reception of my former by the R.S. I here return my acknowledgment to that illustrious company for their great civility.