Leeuwenhoek's Wills

Leeuwenhoek's first wife, Barbara de Meij, died in 1666, and his second wife, Cornelia Swalmius, in 1694, so he lived the last thirty years of his life as a widower. All the wills (testamenten) that we know he made are listed on the timeline of wills and estates. He made a will with Barbara in 1662 and another after her death in 1667. He made a pre-nuptial agreement with Cornelia in 1671 (Roelandus van Edenburgh notary). He outlived both wives.

He and Barbara had five children, but only Maria survived infancy. Maria, who never married, outlived her father by twenty years. She took care of Leeuwenhoek for the last half of his life, had his memorial constructed in the Nieuwe Kerk, and is buried beside him. She made several wills during her lifetime, beginning when she was a teenager: 1671, 1672, 1674, and 1690.

A.J.H. Rozemond's 1992 article Wilsbeschikkingen van Antoni van Leeuwenhoek summarizes these pre-nuptial agreement and wills:

  • October 23, 1662 - Antony and Barbara de Meij, Frans Boogert notary
  • January 17, 1671 - Maria van Leeuwenhoek, Roelandus van Edenburgh notary
  • October 15, 1671 - Cornelia Swalmius

At the end of his life, Leeuwenhoek and Maria made three wills.

  • February 11, 1712 - Jurianus van der Cost notary. Full text (nl) in A.J.H. Rozemond's De Testamenten van Antoni van Leeuwenhoek
  • June 26, 1719 - Nicolaas van der Vaart notary in Delfshaven. Slightly revised in 1721. Full text (nl) in Petra Beydal's Twee Testamenten van Antoni van Leeuwenhoeck
  • November 17, 1721 -  Jan de Bries notary. Amended November 26 and 30. Full text (nl) in Beydal's Twee Testamenten

The 1995 van den Burg and Leeuwenhoek genealogy (nl) has a summary of all of these wills, including the following relatives who were to receive bonds (obligaties):

  • Anthony de Molijn (sister Margrieta's son) - 2,500 guilders (Beydals says 3,500)
  • Margareta de Molijn (his sister Margrieta's daughter) - 1,000 guilders
  • Geertruijt de Molijn (his sister Margrieta's daughter) - the income from two obligaties totaling 2,600 guilders at 4%
  • Jan Haaxman (his sister Margrieta's grandson) - 3,500 guilders
  • Anthony van Leeuwen (his sister Geertruijt's son) - use of Rijkje van Leeuwen's bonds totaling 5,000 guilders
  • Rijkje van Leeuwen (his sister Geertruijt's daughter-in-law) - 5,000 guilders
  • Adriaan Swalmius (his brother-in-law's grandson) - 500 guilders
  • Marija Strik (his niece) - 270 guilders
  • unnamed maid - 300 guilders

Rijkje, Jan and Philips van Leeuwen each got a silver serving bowl and some other jewelry, including for Jan two silver candle sticks made by Leeuwenhoek.

Dirck Haaxman, grandson of Leeuwenhoek's sister Margarieta, got the house on the Hippolytusbuurt.

Beydals says that Margaretha Philips van Leeuwen also got 2,000 gl.

For all the remaining property, Jan and Philips van Leeuwen were the heirs and also were named executors of the estate.

What about his microscopes and papers?

In the will of November 1721, Leeuwenhoek expressed his wishes for his microscopes:

Vorders is ons begeeren dat alle de vergroote glazen geene uytgesondert, die in het cabinet leggen ende meest in cantoortgens sijn opgeslooten met haar comptoirtjens sullen werden op den inventaris gebragt, sonder dat men yder in 't particulier sal op den inventaris te brengen, in een koffer of kist met de gereedschappen, sullen opgeslooten ende versegelt te werden, om tijd ende wijle, na de doot van de langstlevende, soo deselve nog in wesen sijn, in een bondel te verkoopen ten genoege van de heeren executuurs, ende ten meesten voordeel van de nalatenschap.

Further our intention is, that all the magnifying glasses, no exceptions, that lie in the cabinet and mostly are closed up in little containers (cantoorgens) with their [comptoirgens] will be inventoried, without inventorying each one individually, in a case or chest with the instruments, will be closed up and sealed, so that in due course, after the death of the survivor, still being essentially the same, to sell in a bundle to the satisfaction of the gentlemen executors, and to the greatest benefit of the estate.

Did he leave any unpublished letters?


Ook is ons begeerte dat men in een kist ofte koffer sal opsluyten alle de ongedrukte schriften ende brieven, bij mij Leeuwenhoek sijn geschreven, rakende mijne ontdekkinge, nevens tien gesnede koopere plaaten, behoorende tot eenige ongedrukte brieven, waarvoor men seer na vijfhondert gulden heeft betaelt alsmede de vertaling in 't Latijn, daar men een hondert ende seventig guldens voor betaalt heeft ende dat soo lange als den schelm (dit woord is later door Leeuwenhoek geschrapt) Adriaan Beman in 't leven is, ende en sullen die brieven ende die naderhand nog geschreven sijn, ook niet mogen gedrukt werden bij desselfs soon ofte nabestaande.

It is our desire that in one box or suitcase will be closed up all the unpublished writings and letters, written by me, Leeuwenhoek, concerning my discoveries, and ten cut copper plates, belonging to some unpublished letters, for which was paid more than five hundred guilders as well as the translation into Latin, for which was paid seventy guilders and that so long as the villain [word deleted later by van Leeuwenhoek] Adriaan Beman is living, both those letters and those still to be written afterwards, may not be printed by his son or next of kin.

From 1693 to 1702, Leeuwenhoek had published half a dozen volumes of letters printed by his next door neighbor Henrik van Krooneveld. For his Send-Brieven in 1718, he used Adriaan Beman. That relationship apparently did not go well and he died with another volume almost ready for publication. It was offered for sale at the auction of his microscopes in 1747. There is no record that anyone bought it. Nor were any posthumous letters published, so the box of unprinted letters must have been thrown away, perhaps burned, and the copper plates re-used for another purpose.

Maria, as it turned out, survived her father by twenty years. Her will followed the spirit of her father's, though she had to make changes because several of the earlier beneficiaries had died.