Hans Sloane wrote Letter L-411 sometime before November 1703 as a cover letter for the book on Peruvian silver mines and some numbers of Philosophical Transactions

November 1, 1703

This letter is known only by reference in Leeuwenhoek’s reply.

In this letter, Sloane wrote a letter accompanying a book on silver mines that L. had requested as well as some numbers of Philosophical Transactions.

The book that Leeuwenhoek received is Alvaro Alonso Barba’s Arte de los Metales, seguido de notas y suplementos al libro por un antiguo minero. Juicios y comentarios, translated into English as The art of metals in which is declared the manner of their generation and the concomitants of them. Leeuwenhoek had requested it in Letter L-407 of 8 December 1702 to John Chamberlayne after reading reviews of it in Philosophical Transactions, vol. 9, nos. 108 and 109 from 1674. In 1674, by his own admission, L. knew only Dutch. Perhaps thirty years later, he was able to read enough English to make Barba’s book helpful.

Leeuwenhoek had great interest in silver. In Letter L-392 of 2 August 1701 to the Royal Society, Leeuwenhoek described the 26 microscopes he was bequeathing to the Society,

all of which have been ground by me and are in a silver setting and mounted with silver, most of them with the silver I extracted from mineral and separated from the gold with which it was contaminated.

At the 1747 auction of Leeuwenhoek’s microscopes, 170 of his simple single-lens microscopes were marked as made completely of silver and 3 of silver and brass. See Rees, Catalogus van het Vermaarde Cabinet van Vergrootglasen (Catalogue of the renowned cabinet of magnifying glasses) and Zuidervaart & Anderson, “Antony van Leeuwenhoek’s microscopes”. On Leeuwenhoek’s death, he bequeathed to a relative two silver candlesticks that he had made himself. See Beydals, “Twee Testamenten”.

Leeuwenhoek wrote often about silver. For the years close to the present letter, see Letter L-292 of 6 July 1696, Letter L-352 of 1 February 1699, Letter 240 L-409 of 5 February 1703, and Letter 267 L-452 of 17 May 1707.

By “your letters”, Leeuwenhoek must mean the present letter as well as the previous letter from Sloane to Leeuwenhoek, Letter L-402 of sometime before April 1702. Leeuwenhoek had not addressed a letter to Sloane since Letter L-397 of 6 December 1701. Sloane’s next letter to Leeuwenhoek is Letter L-421 of sometime between March and July 1704.


Letter 242 L-412 of 3 November 1703 to Hans Sloane

I have duly received your letters as well as the Transactions and the book on the mines in Peru which you had the kindness to send to me. I am greatly obliged to you for this present and I wish I had an opportunity to show my gratitude properly. If I had had any suspicion that the book was not to be had in the shops, I should not have asked Mr. Chamberlayne for it.