Wrote Letter L-585 of 1723-05-31 to the members of the Royal Society about the structure and texture of the diaphragm, the source of his most severe ailment

May 31, 1723
Standard reference information
Collected Letters volume: 

According to the manuscript, the translator was a different person from the one who translated the earlier Letter L-581 of 20 November 1722 and Letter L-584 of 19 March 1723, but the same who also translated the following Letters L-587 and L-588 of August 1723 into Latin. According to Letter L-590 of 4 September 1723 to James Jurin, this was the Delft surgeon Johannes Hoogvliet. For Hoogvliet, see Letter L-576 of 13 June 1722.

The Latin title in Philosophical Transactions translates to “On the Structure of the Diaphragm. Letter of Antony van Leeuwenhoek, R. S. to the Royal Society.”

This letter was followed by two letters sent posthusmously in August 1723. Neither of them was signed by Leeuwenhoek, so the signature at the end of the present letter is his last known.