Robert Hooke wrote Letter L-112 of 4 July 1681 to thank Leeuwenhoek for previous letters and to promise to respond more promptly in the future

July 4, 1681

This letter is known only by reference in other letters. The date is New Style, which was ten days ahead of the Old Style date of 24 June 1681 used by Hooke in London.

In this letter, Robert Hooke writes that the members of the Royal Society thank Leeuwenhoek for the observations and reasoning in his two previous letters and will have them published. Hooke is concerned that Leeuwenhoek has not had proper answers to his letters and promises to do better in the future.

Leeuwenhoek’s “last two missives” are Letter L-110 of 28 September 1680 to Thomas Gale and Letter L-111 of 12 November 1680 to Robert Hooke. Neither was published in Philosophical Transactions but the latter was published in Philosophical Collections, no. 3, of 10 December 1681.

It was in his own Philosophical Collections, not Philosophical Transactions, discontinued after owner and editor Henry Oldenburg’s death, where Hooke published five of Leeuwenhoek’s letters. The first, Letter L-080 of 25 April 1679, had already been published in Philosophical Collections, no. 1, of 1 November 1679, which Leeuwenhoekuwenhoek apparently was not aware of when he wrote Letter L-114 of 4 November 1681 to Robert Hooke.

The “last letter” from Hooke is Letter L-103 of 22 April 1680. Before Leeuwenhoek received the present letter, he responded with four letters to Hooke, Letter L-105 of 13 May 1680 thanking Hooke for his election to the Royal Society, Letter L-107 of 14 June 1680, a short cover letter, Letter L-109 of 9 August 1680 inquiring about whether his two previous letters were received, and Letter L-111 of 12 November 1680 about, among many other things, blood, sperm in insects, and whether animals can be generated spontaneously. In that same period of time, Leeuwenhoek sent three letters to Thomas Gale and one to the members of the Royal Society, for a total of eight letters without a reply. Leeuwenhoek must have thought it odd that after he was elected a fellow of the Society, he did not get another letter from anyone at the Society until the present Letter L-112 of 4 July 1681, 15 months later.

The excerpt in Documents below from Letter L-114 of 4 November 1681 has a mistranslation. Letter L-113 of 17 July 1681, in this volume, is David Gregory’s cover letter, Letter L-113, not “Your [Hooke’s] letter”.



Letter L-110 of 28 September 1680 to Thomas Gale

In the last letter which I received from your colleague Mr. Robert Hooke, this gentleman assures me that any letter I shall write to him will certainly be answered by you. Now, having sent to the said gentleman some observations on the 14th of June and having up to now received no reply to my request of the 9th of August for acknowledgment of that missive, I cannot but think that my letters are lost. For which reason I take the liberty to address this letter to you, earnestly requesting you kindly to let me know if my above-mentioned letter of the 14th of June has come to hand.

Letter L-114 of 4 November 1681 to Robert Hooke

I received in good order your letter of June 24th, and was much gratified to learn that the simple observations and reasoning, contained in my last two missives, have so much pleased the Royal Society that the members have sent me their cordial thanks through you and that the said gentlemen have ordered them to be published in the Transactions, which are henceforward to be printed every month, without intermission. Your letter, dated July 17th, was forwarded to me from Rotterdam, under cover to the ingenious and noble Mr. D. Gregory. …

I intended to have answered you before thanking you and the honourable College of the Royal Society for all the civilities contained in the letter, but circumstances prevented my carrying out this intention.

Letter 67 [35] L-116 of 3 March 1682 to Robert Hooke

In your last letter you have requested me, on behalf of that honourable college, the Royal Society, to continue my observations and to communicate these to you. You express a fear that I have not duly received the replies to my letters, and promise that in future answers will be regularly sent to me. Having since sent to you a few observations dated November 4th 1681, and having at the same time requested you urgently to send me an answer to a certain cure of the gout, without, however, receiving a reply, I cannot but think that either your missive or mine has been lost.