- de Meij
- de Molijn
- van den Berch
- Hogenhouck family
- Civic career
- Scientific career
- Delft in Holland
Wrote Letter 50 of 1686-05-14 (AB 92) to Members of the Royal Society
May 14, 1686
Text of the letter in the original Dutch and in English translation from Alle de Brieven. The Collected Letters at the DBNL - De Digitale Bibliotheek voor de Nederlandse Letteren.
The original manuscript on ten quarto pages, written by a copyist and signed by Leeuwenhoek, is preserved at the Royal Society (MS. 1912. L 2. 3.).
In the text, Leeuwenhoek noted "I have thought fit to have drawings made of the gall-nuts as they grow on the leaves, and shown here in fig. 1." He did not say anything more about who drew the figures, but all of them with the exception perhaps of Fig. 3 and Fig. 4 seem beyond Leeuwenhoek's skills.
He spoke of collecting his gall nuts and thistle nuts from the nearby Haagse Bos. It was a five-mile trip via the regular Delft-Den Haag ferry service.
However, the gallnuts that illustrated this letter, twice the size of the local specimens, were imported from Aleppo.
The mezzotint portrait of Leeuwenhoek by Johannes Verkolje, dated 1686, had the gallnuts (detail on right; click to enlarge) in Fig. 1 on the worktable in front of Leeuwenhoek. Note also that Leeuwenhoek is holding a wide magnifying glass with three lenses.