Chronology of events: 1687--1694

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.

Date
January 1, 1687 cousin Maarten Pieters Hogenhouck (1650-1720) appointed to Veertigraad, served 1687-1720
January 1, 1687 Published Anatomia Seu Interiora Rerum (Interior Anatomy), 19 Letters from 28 - 52
January 1, 1687 Published Anatomia Seu Interiora Rerum (Interior Anatomy), Letters 43, 42, 38
January 1, 1687 Published Vervolg der Brieven (Continuation of the Letters), Letters 53 - 60
January 27, 1687 cousin Magdaleentje (Helena) Maertens Leeuwenhoek married Barent van Frijtom
February 24, 1687 Edmond Halley wrote Letter L-184 to Leeuwenhoek on behalf of the Royal Society, assuring him that the portraits he sent are received, wondering why he has not sent any observations recently, and enclosing recent numbers of Philosophical Transactions
March 1, 1687 Wrote Letter L-185 of 1687-03-01 to James II, King of England, as the dedication for one of his volumes
March 28, 1687 mentor Constantijn Huygens died
April 4, 1687 Wrote Letter L-186 of 1687-04-04 to the members of the Royal Society about the structure of the teeth of elephants, pigs, humans, oxen, and horses and about toothache
April 5, 1687 Guarantor for Johan Francisco de Raet when he became a citizen of Delft
April 16, 1687 The Royal Society ordered that Letter L-186 about teeth be translated
April 23, 1687 The Royal Society read part of Letter L-186 about the structure of teeth
May 7, 1687 The Royal Society read the latter part of Letter L-186 about the teeth of various animals
May 9, 1687 Wrote Letter L-187 of 1687-05-09 to members of the Royal Society about the structure of 'stone' of the medlar and the coffee bean and acid in plants
May 14, 1687 The Royal Society read and discussed part of Letter L-187 about embryo plants in seeds
June 4, 1687 The Royal Society read and discussed part of Letter L-187 about coffee
June 11, 1687 cousin Adriaen Lambrechts Leeuwenhoek admitted as notary
June 13, 1687 Wrote Letter L-188 of 1687-06-13 to members of the Royal Society about wheat and the seeds from a variety of plants
June 18, 1687 The Royal Society read part of Letter L-175 about gall nuts, over a year after receiving it
July 11, 1687 Wrote Letter L-189 of 1687-07-11 to members of the Royal Society about eggs of silkworms and caterpillars and humans' squinting and a theory for its cause
August 6, 1687 Wrote Letter L-190 of 1687-08-06 to members of the Royal Society about the calander and the louse and against spontaneous generation
August 6, 1687 Wrote Letter L-191 of 1687-08-06 to Robert Boyle about his recent letters
September 9, 1687 Wrote Letter L-192 of 1687-09-09 to members of the Royal Society about ant eggs, larvae and its development, feeding, sting, cocoon and nest
October 7, 1687 Appointed curator of the abandoned estate of Evert van der Sijde
October 17, 1687 Wrote Letter L-193 of 1687-10-17 to members of the Royal Society about amber, 'burned paper' from the sky, rotifers, maggots, blow flies, the stinging hairs of nettles, and the East-Indian centipede
November 24, 1687 nephew Johannes Adriaans Swalmius married Magdelena van Mierop
November 26, 1687 The Royal Society read part of Letter L-192 about the generation of ants
November 28, 1687 Wrote Letter L-194 of 1687-11-28 to members of the Royal Society about his discovery that cochineal was an insect and his experiments with cinchona bark
December 3, 1687 The Royal Society read and discussed the latter part of Letter L-192 about the generation of ants
December 11, 1687 The Royal Society ordered that Letter L-194 be translated
January 1, 1688 Published Vervolg der Brieven (Continuation of the Letters), Letters 53 - 60 (2nd)
January 1, 1688 Wrote Letter L-195 of sometime in 1688 to Robert Boyle, now lost
April 2, 1688 printer-bookseller Hendrik van Cronevelt bought the house next door
May 25, 1688 Wrote Letter L-196 of 1688-05-25 to members of the Royal Society about a medicinal root and bladderstones
July 6, 1688 Wrote Letter L-197 of 1688-07-06 to the members of the Royal Society bezoar stone, monkey stone, gout tubercles, and red coral and white coral
August 3, 1688 Wrote Letter L-198 of 1688-08-03 to the members of the Royal Society about plaster, alabaster, gypsum, Muscovite glass, cobblestone, shell lime, masonry mortar, lime, cement, sand stone, and slate
August 24, 1688 Wrote Letter L-199 of 1688-08-24 to the members of the Royal Society about gnats, horseflies; growth of branches, germination of wheat plants, the soft and hard roe of cod, and the number of sperm in a cod's soft roe
September 7, 1688 Wrote Letter L-200 of 1688-09-07 to the members of the Royal Society about development of the eggs of green frogs, blood circulation in frogs and the tail fin of roach and bream, and the shape of red blood cells
September 15, 1688 Published Den Waaragtigen Omloop des Bloeds (On the True Circulation of Blood), Letter 65 (L-200)
September 23, 1688 Wrote Letter L-201 of 1688-09-23 to Melchisedec Thevenot, a cover letter for a copy of Leeuwenhoek's Letter L-200, published separately as Den waaragtigen omloop des bloeds.
January 1, 1689 Published Continuatio Epistolarum (Continuation of the Letters), Letters 53-60
January 1, 1689 Published Tweede Vervolg der Brieven (Second Continuation of the Letters), Letters 61 - 67
January 1, 1689 Wrote Letter L-202 of sometime in 1689 to Antonio Magliabechi, a cover letter for one of his books
January 12, 1689 Wrote Letter L-203 of 1689-01-12 to Robert Boyle, a cover letter for Continuatio epistolarum and a copy of Letter L-204
January 12, 1689 Wrote Letter L-204 of 1689-01-12 to the members of the Royal Society about his observation of the circulation of the blood in a variety of fish as well as a description of the construction of his ‘eel spy-glass’ and the slime on the skin of an eel
March 6, 1689 Christiaan Huygens wrote Letter L-205 to Leeuwenhoek, thanking him for the gift of a mangrove tree and inquires whether L.’s observations of the circulation of the blood could also be seen in the wings of bats, the legs of ducks, and the ears of rats
April 1, 1689 Did not write any letters between April 1689 and mid-September 1691
April 1, 1689 Wrote Letter L-206 of 1689-04-01 to the members of the Royal Society
April 23, 1689 Appointed guardian of the children of Jacob Bellart
May 27, 1689 Anthonie Heinsius became Grand Pensionary of the States of Holland
June 21, 1689 nephew Adriaan Johannes Swalmius baptized, witnessed by Antony and Cornelia
October 1, 1689 Wrote Letter L-207 of October 1689 to Christiaan Huygens about sending books to his brother Constantijn Huygens in London
October 19, 1689 cousin Adriaen Lambrechts Leeuwenhoek married Eva Jacobs Overschie
March 6, 1690 Christiaan Huygens wrote Letter L-208 to Leeuwenhoek about liquids in glass balls and Iceland crystal
April 3, 1690 cousin Maarten Lambrechts Leeuwenhoek married Margareta Pieters van Limburg
April 17, 1690 daughter Maria made a will
September 7, 1690 Bought the other part of the garden outside the walls of the city
January 1, 1691 Published Onsigtbare Verborgentheden (Invisible Mysteries), Letters 38, 42, 43 (2nd)
March 2, 1691 Gottfried Leibniz wrote to Christiaan Huygens praising Leeuwenhoek, "who tells me what he observes"
May 27, 1691 Antonio Magliabechi wrote Letter L-209 of 1691-05-27 to Leeuwenhoek about book news and Leibniz's reaction to some of Leeuwenhoek's observations
September 18, 1691 Wrote Letter L-210 of 1691-09-18 to Antonio Magliabechi about
September 21, 1691 William Stanley wrote Letter L-211 of 1691-09-21 to Leeuwenhoek, a courtesy letter
October 21, 1691 Appointed executor of estate of his maid, Neeltie Jan de Vries
November 10, 1691 maid Neeltie Jans de Vries died
November 27, 1691 Wrote Letter L-212 of 1691-11-27 to the members of the Royal Society about blood, chyle, and an experiment to discover the volume of water when it is cold and when it is heated
December 2, 1691 mentor Cornelis 's Gravesande died
December 5, 1691 mentor Cornelis 's Gravesande buried
December 6, 1691 brother-in-law Jan Jacobs de Molijn buried
January 1, 1692 William Molyneaux wrote about a visit to Leeuwenhoek
January 4, 1692 Wrote Letter L-213 of 1692-01-04 to the members of the Royal Society about bladder and kidney stones and a chalk-like substance from a gout stone
January 13, 1692 niece Geertruijt Jans de Molijn inherited property from her father Jan Jacobs
February 1, 1692 Robert Hooke called Leeuwenhoek the microscope's "single votary"
February 1, 1692 Wrote Letter L-214 of 1692-02-01 to the members of the Royal Society about various peppers and their taste, tea and its effects of tea on digestion, and Spanish fly
February 12, 1692 Richard Waller wrote Letter L-215 to Leeuwenhoek about his recent observations and the structure of grass
March 7, 1692 Wrote Letter L-216 of 1692-03-07 to the members of the Royal Society about corn-weevels, corn-moths, caterpillars, butterflies, calanders, lice in corn-lofts, little animals in rain water, black-flies in blossoms, and maggots in cheese
March 19, 1692 Reimbursed for purchase of distilled water and wine
April 22, 1692 Wrote Letter L-217 of 1692-04-22 to Richard Waller about the construction of an air pump and experiments with different liquids, seeds and small stones in urine, a hog's hair in the skin of a child, and grains of wheat
June 24, 1692 Antonio Magliabechi wrote Letter L-219 of 1692-06-24 to Leeuwenhoek about recent books that he thought might be of interest by Ramazzini and Guiglielmini
June 24, 1692 Wrote Letter L-218 of 1692-06-24 to the members of the Royal Society about more experiments with his air-pump, the structure of and blood in an insect's wing, a grey owlet moth, and the wing of a very small fly
July 22, 1692 Christiaan Huygens began second series of observations of little animals replicating and expanding on Leeuwenhoek's
August 12, 1692 Wrote Letter L-220 of 1692-08-12 to the members of the Royal Society about the shaft of a bird's feather as used in a quill, the lens and cornea of the human and calf eyes, 'wood-pipes' in different species of wood, bulrushes, and pine and lime wood
September 16, 1692 Wrote Letter L-221 of 1692-09-16 to the members of the Royal Society about little animals in dental tartar, theories of eel reproduction, worms in eel intestines, and blood vessels in grasshoppers
September 23, 1692 Wrote Letter L-222 of 1692-09-23 to Mary, Queen of Great Britain, the dedication to Derde Vervolg der Brieven
October 20, 1692 Christiaan Huygens wrote Letter L-223 to Leeuwenhoek about the procreation of eels and spontaneous generation and praised his work and diligence
November 29, 1692 cousin Sara Maertens Leeuwenhoek married Cornelis Luda
December 21, 1692 cousin Jacob Adriaens Leeuwenhoek (1692-1724) baptized
February 28, 1693 editor Richard Waller began publishing Leeuwenhoek again in Philosophical Transactions
March 25, 1693 Published Derde Vervolg der Brieven (Third Continuation of the Letters), Letters 68 - 75
April 4, 1693 Received an honorarium from the city for his books of letters
May 8, 1693 Richard Waller wrote Letter L-224 to Leeuwenhoek about colors of feathers and univocal generation
May 23, 1693 De la Croze called Leeuwenhoek a "curious Observer of Nature"
July 1, 1693 Wrote Letter L-225 of 1693-07-01 to Richard Waller, cover letter for a volume in Latin and confirmation of receipt of Letter L-224
August 18, 1693 Pieter Rabus wrote Letter L-226 to Leeuwenhoek praising his accomplishments and including a laudatory poem
September 3, 1693 George Garden wrote Letter L-227 to Leeuwenhoek about the role of egg and ovaries in reproduction
September 18, 1693 Paulus Durven appointed curator
September 26, 1693 cousin Sara Maertens Leeuwenhoek buried
September 30, 1693 Edmund King replicated Leeuwenhoek's observations of little animals in pepper water
October 15, 1693 Wrote Letter L-228 of 1693-10-15 to the members of the Royal Society about colors and the life cycle of fleas
October 27, 1693 Wrote Letter L-229 of 1693-10-27 to Pieter Rabus about procreation of the flea, the leather-jacket, and the mite
November 19, 1693 nephew Johannes Adriaans Swalmius buried
November 21, 1693 Appointed guardian of his dying wife Cornelia Swalmius
November 30, 1693 Hans Sloane was elected Secretary of the Royal Society and editor of Philosophical Transactions, publishing 68 articles by Leeuwenhoek over the next twenty years
December 5, 1693 Rented St. Agnieten Tooren from the city for 12 years
December 7, 1693 wife Cornelia Swalmius made a will
December 8, 1693 Wrote Letter L-230 of 1693-12-08 to Richard Waller, a cover letter
December 20, 1693 Wrote Letter L-231 of 1693-12-20 to the members of the Royal Society about spiders, lice, and mites
December 26, 1693 wife Cornelia Swalmius made a will including Maria
December 29, 1693 Sold the garden outside the walls of the city
December 31, 1693 Promised to pay five gulden for the ransom of a neighbor's son from Algerian pirates
January 1, 1694 Published Onsigbare Geschapene Waarheden (Invisible Creation Truths), Letters 32, 39, 33
January 1, 1694 Published Vierde Vervolg der Brieven (Fourth Continuation of the Letters), Letters 76 - 83
January 6, 1694 wife Cornelia Johannes Swalmius buried
January 19, 1694 Wrote Letter L-232 of 1694-01-19 to Richard Waller as a cover letter for Letter L-231
January 24, 1694 Wrote Letter L-233 of 1694-01-24 to the members of the Royal Society about tapeworms and salt and sand in cod intestines
February 10, 1694 Richard Waller wrote Letter L-234 to Leeuwenhoek, asking him to examine the colors of birds' feathers and other bodies, such as silk, paint, and mercury and whether he had observed sperm inside of an egg
February 12, 1694 Presented act of guardianship to the Weeskamer after Cornelia's death
February 12, 1694 Wrote Letter L-235 of 1694-02-12 to Richard Waller as a cover letter for Letter L-233
February 24, 1694 Wrote Letter L-236 of 1694-02-24 to the members of the Royal Society about his experiments with solid phosphorus
February 28, 1694 Benedictus Haan wrote Letter L-237 to Leeuwenhoek agreeing with him against George Garden about the female ovary
March 2, 1694 Antonio Magliabechi wrote Letter L-238 of sometime before 1694-03-02 to Leeuwenhoek about recent books that he thought might be of interest
March 2, 1694 Presented Cornelia's will to the Weeskamer
March 2, 1694 Wrote Letter L-239 of 1694-03-02 to the members of the Royal Society about ear wax and hair, body hair, the amount of sweat secreted from the human body, and the possibility that sperm might penetrate the ovum
March 19, 1694 Wrote Letter L-240 of 1694-03-19 to the members of the Royal Society refuting George Garden's ideas in Letter L-227 about the role of the ovary and eggs
April 2, 1694 Wrote Letter L-241 of 1694-04-02 to the members of the Royal Society about the tongue of an ox and a pig and the heart of a sheep, ox, duck, chicken and cod
April 30, 1694 Wrote Letter L-242 of 1694-04-30 to the members of the Royal Society about his criticisms of Buonanni's theory of spontaneous generation, about mussels, barnacles, shrimp larvae, the eye of a dragon-fly, gnat, fly, and ant, and about ant eggs
May 2, 1694 Richard Waller wrote Letter L-243 to Leeuwenhoek about recent observations, to request a portrait, and to introduce Mr. Walfort, who delivered it
May 11, 1694 Received an honorarium from the city for Vierde Vervolg der Brieven (Fourth Continuation of the Letters)
May 26, 1694 Wrote Letter L-244 of 1694-05-26 to Richard Waller, cover letter for copy of Vierde Vervolg der Brieven
June 4, 1694 Visited Pieter Rabus in Rotterdam
July 7, 1694 Royal Society accepted gift of Vierde Vervolg der Brieven and read Leeuwenhoek's cover letter, Letter L-244
July 30, 1694 Arnold Ramp appointed tax collector for livestock sales
September 14, 1694 Wrote Letter L-245 of 1694-09-14 to Richard Waller about blood circulation and having sent six copies of his portrait to London
November 3, 1694 Lent 400 guilders to Leendert van Bijstervelt
November 24, 1694 cousin Maerten Huijchs Leeuwenhoek buried
November 29, 1694 microscopist Marcello Malpighi died
November 30, 1694 Wrote Letter L-246 of 1694-11-30 to Pieter Rabus about about dragon-fly eyes and eggs, crab eyes, vertebrate corneas, another rejection of spontaneous generation, and the impregnation of women