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

April 11, 1721
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The Journal Book Original, vol. 13, p. 194, for 10 May 1722 indicates that the Royal Society waited a year before reading this letter, until James Jurin was elected second secretary and editor of Philosophical Transactions on 30 November 1721: “The remaining part of a Letter from Mr. Leeuwenhoeck dated the 11 of April was read. Mr. Leeuwenhoeck was ordered Thanks.”