Nehemiah Grew and Robert Hooke wrote to Leeuwenhoek asking him to further observe sperm

January 1, 1678

This letter of 1 January (O.S.), 12 January (N.S.) is known only from reference to it in Leeuwenhoek's response, Letter No. 38 [24] of 18 March 1678.

The letter was co-signed by Robert Hooke.


Letter No. 38 [24] of 18 March 1678

I duly received your letter of January 1st, signed by you and Mr. Robert Hooke (as secretaries of the Royal Society). I saw from it that, owing to the weak health of Viscount Brounker, Sir Joseph Williamson, Knight, Private Secretary of His Majesty the King and a prominent promotor of science, has been elected President in his stead. Also, enclosed, a letter (signed only by you) from which I see that Viscount Brounker was exceedingly pleased to receive my letters and enjoined you to communicate this to me. I was glad to read this. I request you to offer his Lordship my humble salutations. In the same letter you ask me to institute observations concerning the sperm of dogs, horses, and other animals, that I may in future take away any doubt, and for the purpose of discovering whether there is any difference in the number or shape of the little animals.