Nehemiah Grew wrote Letter L-075 of 1678-10-13 to Leeuwenhoek that Letter L-073 about male sperm and female ovulation in humans would be printed "as far as decency permits"

October 13, 1678

This letter is known only by reference in other letters.

In this letter, Nehemiah Grew writes that the observations in L.’s Letter L-073 of 31 May 1678 were welcome to the Royal Society and that some would be printed, “as far as decency permits”. Grew also told L. that he had given the Letter L-074 of 27 September 1678 to the translator and promised to send Philosophical Transactions nos. 139 and 140, which had a description of a foetus found outside the mother’s womb as well as a dropsical testicle of a woman.

Grew’s previous letter to Leeuwenhoek is Letter L-071 of 20 April 1678. The letters to Grew that L. refers to in the present letter are Leeuwenhoek’s replies, Letter L-073 of 31 May 1678, about male sperm and female ovulation, and Letter L-074 of 28 September 1678, about the effects of sun on skin, sweat pores, globules in saliva and their relationship to the globules in blood, and a parasitic grass-rust affecting meadows outside Delft. Both letters are in Collected Letters, vol. 2.

The present letter is Grew’s last known letter to Leeuwenhoek, although Leeuwenhoek would send three more letters to Grew in response to his request in Letter L-066 of 11 January 1678, that L. investigate sperm in a variety of animals. The letter that the Royal Society never received, Letter L-078 of 21 February 1679 refutes the opinion that living organisms occur in blood or saliva and describes cod sperm. Letter L-080 of 25 April 1679 describes sperm in cod, pike, hare, cock and dog as well as calculates their numbers. Finally, in Letter L-087 of 13 June 1679, Leeuwenhoek asks Grew to acknowledge his letters of February and April. There is no record that he did so, but perhaps Robert Hooke’s lost Letter L-091 of August 1679, did it for him.

In Leeuwenhoek’s Letter L-092 to Hooke of 13 October 1679, he writes:

I have sent three several [separate] letters to your colleague, Mr. Nehemiah Grew, without receiving a reply, to my great surprise. At one time I think the reason must be this gentleman’s many occupations, at another time I wonder whether illness may not be the cause, and then again I think the Royal Society may not have met. These ideas repeatedly entering my mind, I take the liberty to address this letter to you, requesting you to inform me whether my last letter, dated April 25th 1679, has come to hand.


Letter L-078 of 21 February 1679 to Nehemiah Grew:

I was glad to see from your kind and agreeable letter of October 3rd that my observations of May 31st were welcome to yourself and to the Royal Society, and that some of my observations, as far as decency permits, will be published. I am looking forward to that publication and also to Transactions Nos. 139 and 140, which you say contain a description of a foetus not found in the mother’s womb but in the membrane or suct, and also of a dropsical testicle of a woman.

Letter L-087 of 13 June 1679 to Nehemiah Grew

In your favour of October 3rd 1678 you say that two days before, you received my letter of September 28, and that you gave it to a translator, after which you would send me an answer and a few Transactions.