Richard Waller wrote Letter L-224 to Leeuwenhoek about colors of feathers and univocal generation

May 8, 1693

Text of the letter in Alle de Brieven / The Collected Letters at the DBNL - De Digitale Bibliotheek voor de Nederlandse Letteren.

The date is New Style, which was ten days ahead of the Old Style date of 28 April 1693 used by Waller in London. 

The original letter and drawing have been lost. Leeuwenhoek included parts of it in a letter he wrote to the Royal Society the following October. He also published in Holland in Dutch and Latin translation.

The letter discussed the structure of feathers and encouraged Leeuwenhoek to investigate the colors of feathers. Waller was noted for his detailed illustrations of plants, one of which he enclosed with this letter. Waller also discussed his agreement with Leeuwenhoek about "univocal generation", that plants and animals all come from genetically related parents, no exceptions.

Waller read this letter at the 1693-05-12 O.S. meeting of the Royal Society.

Leeuwenhoek responded with a letter of thanks, Letter L-225 of 1 July 1693 and, three months later, Letter L-228 of 15 October 1693 with his observations on colors and on the procreation of fleas as an example of univocal generation.


Letter Book Original, vol. XI, pt. I, pp. 140-141.

Journal Book Original, vol. IX, p. 122

Mr. Wallers Letter to Mr. Leewenhoek was read in answer to two formerly sent by him, the one about the structure of Feathers, desiring him to consider their Texture, where they are of differing colours: The other about the impossibility of aequivocall Generation.