Henry Oldenburg wrote to Leeuwenhoek recommending that he get help from knowledgable people

April 12, 1675

Because this letter is lost, only Leeuwenhoek's reply of August 14 indicates what Oldenburg wrote about. Leeuwenhoek replied to him:

I duly received your agreeable letter of April 12th ultimo. I was glad to see from it that my slight observations in my letter of March 26th pleased you so much; also your unmerited friendly disposition towards me. ... You recommend me to call in the assistance of other persons, capable of judging of such things. Allow me to say, Sir, that there are very few people in this town that could assist me, and as to people that come to visit me from other places, well, recently I had one here who rather intended to dress himself in plumage borrowed from me, than to lend me a helping hand