Wrote Letter L-525 of some years before 1716 to Frederik Adriaan van Reede about the large number of eggs in the roe of a ling
This letter is known only by reference in another letter.
In this letter, L. writes in detail to Van Reede about the large number of eggs in the roe of a ling.
Letter L-527 of 3 March 1716 to Gottfried Wihelm Leibniz
Some years ago, … I saw the roe, or ovary, of a fish which we call a ling, which appeared to me to have an exceptional size. I gave order to weigh this roe, and it was found to weigh 5 1/2 pounds; and computing as well as I could, I found the volume in cubic inches which was contained in the roe, and then how many of those eggs, the one lying next to the other, made up the length of an inch, and in that way I found that the roe, or ovary, contained 9344000 eggs; at that time I have written in greater detail about this to the most noble gentleman, the Baron van Rhede.
This letter is difficult to date because in no previous letter does Leeuwenhoek’s computation of eggs involve the number 9344000. In only two letters did Leeuwenhoek discuss ling, Letter L-457 of 25 July 1707 and Letter L-481 of 22 September 1711, both addressed to the Royal Society. The only previous letters from Leeuwenhoek to Van Reede about sea creatures were letters in 1695 and 1696 about oysters and L-368 of 2 June 1700 about shrimp.
Leeuwenhoek’s previous letter to Van Reede was Letter L-393 of 26 August 1701 about measuring the fall of water. His next and final letter was Letter L-558 of 10 September 1717 about, among other things, how the fish’s scales determine the age of herring, perch, bream, and cod. There was no known reply from van Reede to either letter.
