Letters written by Leeuwenhoek during Period 7

Alle de Brieven / Collected Letters has over 350 letters. However, only those in this chronology that Leeuwenhoek designated Letter 1, Letter 2, etc. did he consider to contain publishable microscopic observations.

Date
January 9, 1720 Wrote Letter L-565 of 1720-01-09 to the members of the Royal Society about muscle fibres and membranes of a cow, mites on the flesh of a whale, and the nerves around the muscle fibres and tendons of a cow
November 20, 1720 Wrote Letter L-566 of 1720-11-20 to the members of the Royal Society about bone membrane and the canals in bone, the cell layers and blood vessels in the bone membrane, and bone from the rib of a cow
January 15, 1721 Wrote Letter L-567 of 1721-01-15 to members of the Royal Society about the stomata of the leaves of boxwood, the number of them, and the down on the skin of a peach and a quince
January 24, 1721 Wrote Letter L-568 of 1721-01-24 to the members of the Royal Society about vessels in wood from Ambon (Indonesia), oakwood, and pinewood, the muscle fibres of a cow, a whale, and a mouse, and the structure of a red blood cell
April 11, 1721 Wrote Letter L-569 of 1721-04-11 to the members of the Royal Society about how flesh fibers are nourished by the blood vessels, this time in fish
June 27, 1721 Wrote Letter L-570 of 1721-06-27 to the members of the Royal Society about finally discovering the little holes in the membranes of beans and peas and about the little vessels in seed membranes
April 21, 1722 Wrote Letter L-572 of 1722-04-21 to the members of the Royal Society about the muscular fibres of different animals and whether iron becomes magnetic over time
May 1, 1722 Wrote Letter L-573 of 1722-05-01 to the members of the Royal Society about the structure of fat particles in sheep, lamb, flatfish, and perch
May 1, 1722 Wrote Letter L-574 of 1722-05-01 to James Jurin, a cover letter to Letter L-573, asking for support for his observations of hermaphroditic animals
June 13, 1722 Wrote Letter L-576 of 1722-06-13 to the members of the Royal Society about the reproductive organs of a ewe and a fetus from it
June 13, 1722 Wrote Letter L-577 of 1722-06-13 to James Jurin, a cover letter for Letter L-576, expressing doubts that inoculations protect against smallpox
July 7, 1722 Wrote Letter L-578 of 1722-07-07 to the members of the Royal Society about calluses on human skin
July 7, 1722 Wrote Letter L-579 of 1722-07-07 to James Jurin, a cover letter to Letter L-578, that no little animals are to be found in smallpox pustules; again opposes a proponent of spontaneous generation
November 20, 1722 Wrote Letter L-581 of 1722-11-20 to James Jurin about the miscroscopic structure of diamonds and rock crystal
March 19, 1723 Wrote Letter L-583 of 1723-03-19 to the members of the Royal Society about blood, now lost
March 19, 1723 Wrote Letter L-584 of 1723-03-19 to James Jurin about blood, the size of blood globules, the state of his health, and the role of the ovary in reproduction
May 31, 1723 Wrote Letter L-585 of 1723-05-31 to the members of the Royal Society about the structure and texture of the diaphragm, the source of his most severe ailment
August 1, 1723 Wrote Letter L-587 of sometime in August to James Jurin about the similarities between globules in blood and in the lees of wine to argue against Jurin’s hope to discover how blood globules are made
August 1, 1723 Wrote Letter L-588 of 1723-08-00 to James Jurin about his spermist view of the generation of animals and palpitations of his diaphragm, his final letter