At age 52, his 25th article in Philosophical Transactions

Date: 
February 23, 1685

At age 52, his 25th article in Philosophical Transactions, volume 15, number 168 (February 1685): An Abstract of a Letter of Mr. Anthony Leewenhoek Fellow of the R. Society; Concerning the Parts of the Brain of severall Animals; The Chalk Stones of the Gout; The Leprosy; And the Scales of Eeles.

Because some letters were split into two articles and other articles contained two letters, Letter 42 of 1684-07-25 (AB 81) to Members of the Royal Society is the 24th letter that Leeuwenhoek had published in Philosophical Transactions.

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