Primary sources



printed in London (Philosophical Transactions)

printed in Leiden and Delft

The focus of this web is the life of Leeuwenhoek, his letters, his science, and especially his life in Delft. The Secondary literature below shows how widely that net that can be cast. The primary sources document the central focus: Leeuwenhoek's letters and his life in official and private documents preserved in archives, most in the Dutch Republic, some in London, and a few elsewhere in Europe.

Leeuwenhoek's letters

As did everyone else in the days before email, Leeuwenhoek wrote thousands of letters. Some two hundred have survived, They have survived in manuscript and in print in Alle de Brieven, in his Dutch and Latin publications, and in all of the Philosophical Transactions articles in English and occasionally Latin translation. These primary sources include all of the original drawings and engraved figures. None of the intermediate plates has survived, that is, the engravings from which the prints were made.

Not included among these priary soures are contemporary excerpts and translations of Leeuwenhoek's letters in journals, chiefly German, French, and Latin. Hoole's version, decades after Leeuwenhoek's death, is of interest chiefly for the quality of its translations. These resources are treated here as secondary literature outside the primary focus of this web.

Although many of Leeuwenhoek's manuscripts are lost, the corpus is complete in Dutch and will soon be complete in English. By 2023, the final volumes should be digitized and free of copyright restrictions, providing opportunities for text mining.

Pre-1750 archival documents

These primary sources are manuscripts, mostly bound, and never printed. For the bulk of them, see Delft City Archives below under Learn more. Scans of thousands of these original handwritten documents relating to Leeuwenhoek's life in Delft are available online using some of the Tools below. I have scanned hundreds more in order to make them available on Lens on Leeuwenhoek. 

The archivists in Delft, Den Haag, Utrecht, Haarlem, and Amsterdam are with great care and perseverance digitizing their collections, but they have a long way to go. Much is still to be found in volumes that may not be digitized for a long time.

How did the other biographers
organize their resources?

Dobell in 1932


Publications of letters in Delft and Leiden

 Rabus, Magliabechi, Hoole

Other References and Sources

Schierbeek in 1950

Leeuwenhoek's Gepubliceerde Brieven (Leeuwenhoek's published letters): Cole’s 1937 list, omitting Hoole, including all Phil Trans articles and adding Alle de Brieven through vol. 5

Nederlandse Uitgaven (Dutch publications) of letters in Delft and Leiden

Latijnse Uitgaven (Latin publications) of letters in Delft and Leiden

Rabus, Magliabechi, Hoole

Literatuur: everything else

Secondary Literature




Mid-2017 search results for < Leeuwenhoek -hospital -ziekenhuis > (to exclude the Leeuwenhoek cancer hospital in Amsterdam):

general Google: 499,000 results  

Google Books: 929,000

Google Scholar: 98,000

To focus more closely on his life < Leeuwenhoek Hippolytusbuurt >

general Google: 41,900 results  

Google Books: 163

Google Scholar: 19

As another rough indicator, WorldCat lists about 8,500 books and articles with Leeuwenhoek in the title.

The list of secondary literature on Lens on Leeuwenhoek is quite a bit shorter than 929,000 and quite a bit longer than 163. The books and articles included here were originally published in print, English or Dutch only, with a few exceptions for French, German, and Italian publications during Leeuwenhoek's lifetime. Most of this secondary literature is available online, many immediately as links from Lens on Leeuwenhoek.

The print bibliography can be sorted by author, title, and date. Further grouping by topic and related sources, people, events, and letters are found on the annotated page for each title.

A special kind of secondary source is one that was never published in print. Pre-Internet, its only option for publication would have been ink on paper. Lens on Leeuwenhoek is one such secondary source. Concerning Leeuwenhoek, however, there are very few other webs that include material that is interesting and helpful for understanding more about Leeuwenhoek's life, letters, and science.

Another special kind of secondary source is video. As far back as 1924, people were making films about Leeuwenhoek. YouTube has dozens of them, many school projects. The dozen or so videos (and one radio play!) cited on Lens on Leeuwenhoek seem the most substantive and helpful.


While neither a primary source nor a part of the secondary literature, some of the research tools most helpful to the Leeuwenhoek scholar are worth including in the Resources section of Lens on Leeuwenhoek.

  • Inventories of the documents in the Dutch archives, especially Gemeentearchief Delft. See Delft City Archives below under Learn more.
  • Web repositories, especially those for downloading primary sources
  • Web databases, especially those for locating and downloading books and articles on the Secondary literature lists.
  • Dictionaries, especially those available to Leeuwenhoek
  • Other tools for finding primary sources and secondary literature

As with the secondary sources, these tools are sorted in the Related sources sections of the relevant pages.

Master list of all resources used on Lens on Leeuwenhoek