John Chamberlayne wrote to Hans Sloane about difficulties translating Leeuwenhoek's Dutch, "so abstruse that even his own countrymen cannot explain him"
Chamberlayne continued to have trouble translating Leeuwenhoek's letters. Consulting native Dutch speakers did not always help.
Adriaan van Borssele van der Hooghe (1658-1728), lord of Geldermalsen. In 1699, he was appointed envoy extraordinary to the English court, where he must have become acquainted with Chamberlayne.
Chamberlayne wrote to Sloane (British Library, Sloane MS 4038 f. 171):
For want of grammar he [Leeuwenhoek] is sometimes so abstruse that even his own countrymen cannot explain him. [He omitted a whole paragraph] which Mr de Geldermalsen himself could make nothing of it.
When he keeps to a bare relation of fact he is one of the greatest men in the world, but when he begins to philosophise he is one of the least.