Chronology of events: visitors

For some events, the year is certain but the month and day are not. Example: We know only the year for the collections of Leeuwenhoek's letters published in Dutch during his lifetime.

For other events, the season or month are certain but the day is not. Example: Leeuwenhoek mentions that someone visited him "last month".

On the other hand, many events did indeed happen on the first day of a month. Example: public appointments to Delft's city offices took effect on January 1 of each year. Thus:

  • A date of January 1 in a given year may indicate that the year is certain but the month and day are not.
  • A date of 1 in a given month may indicate that the year and month are certain but the day is not.

Unless otherwise indicated, for events in England, the date given is Old Style, 10 days behind the Dutch Republic's New Style until 1700 and then 11 days behind.

August 11, 1674 Visited by Holger Jacob├Žus, the Bartholin brothers, and Arent Seyn; described as "ingenious but illiterate"
August 15, 1674 Visited by Johannes Swammerdam
July 1, 1676 Visited by Christiaan Huygens during the summer; he saw the little animals in Leeuwenhoek's infusions
November 18, 1676 Visited by Gottfried Leibniz
September 11, 1677 Visited by Hennig Brand, the Hamburg merchant who discovered phosphorus
May 1, 1679 Visited by James, Duke of York, and "several high personages"
January 1, 1682 Visited by Cornelis Bontekoe
January 1, 1683 Visited by Marie-Anne Mancini, Duchess of Bouillon and others
February 5, 1685 Visited by Thomas Molyneux on behalf of the Royal Society
June 22, 1685 Visited by John Locke
October 1, 1685 Visited by Karl von Hessen-Kassel and Willem Meester sometime in October
December 1, 1685 Visited by De Saingermain, who later called Leeuwenhoek a "Magus"
November 5, 1686 Visited by Jacob Gronovius
January 1, 1692 William Molyneaux wrote about a visit to Leeuwenhoek
June 28, 1695 Visited by Johann Wilhelm von Pfalz-Neuburg, Elector Palatine, his wife and his mother
April 1, 1697 Visited by Johann Anderson, a German lawyer and natural scientist
June 1, 1697 Visited by Sir Francis Child, an English banker and politician
October 15, 1697 Visited by Tsar Peter the Great of Russia
January 1, 1700 Visited (possibly) by Hans Sloane, his editor at Philosophical Transactions
March 30, 1705 Visited by Pieter Valkenier
October 1, 1705 Visited by Francesco Cornaro
March 7, 1706 Visited by Govert Bidloo
July 7, 1707 Visited by Gilbert and Thomas Burnet
January 2, 1710 Visited by Alexander Stuart and two Scots gentlemen
November 27, 1710 Visited by John Farrington
December 4, 1710 Visited by Zacharias Conrad von Uffenbach: "more of ingenuity than foundation"
May 9, 1714 Visited by Dr. Richard Bradley, professor of botany at Cambridge
July 1, 1715 Visited by Joachim Georg Reinerding
September 1, 1716 Visited by Hermaan Boerhaave, Frederik Ruysch, and Abraham van Bleiswijk
October 1, 1716 Visited again by Joachim Georg Reinerding
July 15, 1723 Visited by Matthew Raper