The Royal Society read the first part of Leeuwenhoek's long letter of the previous October 9

Date: 
February 11, 1677

On February 1 in London (February 11 in Delft), the Royal Society read the first part of Leeuwenhoek's long letter of the previous October 9. They asked that he "communicate his method of observing." According to Birch's History, vol 3, pp. 332

There was read part of a very long letter of Mr. Leewenhoeck to Mr. OLDENBURG, dated at Delft, 9th October, 1676, which had not been produced before, because it could not be sooner translated into English out of the Low Dutch language, in which it was written. The contents thereof were a great number of observations made by Mr. Leewenhoeck with his microscope, concerning certain little animals found by him in vast quantities in common water, snow-water, well-water, and such water, wherein several sorts of spices had stood infused, both whole and pounded.

It was ordered, that the sequel of these observations should be read at the next meeting; and that the author be desired to communicate his method of observing.

Oldenburg did so in his letter of February 12 (February 22 in Delft).

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