Leeuwenhoek describes tiny organisms in a letter

Leeuwenhoek sent his observations to Henry Oldenburg in London for discussion at the Royal Society.

The letter compared well, rain, sea and other waters through a microscope; identification of individual species came later.

The 9 October account became important to the later history of microbiology, although it was not yet a theory of infectious disease.

Historical accounts date Boylston’s first group to 26 June: his son Thomas and the enslaved Jack and Jackey were inoculated against smallpox.

Jack and his young son Jackey were enslaved by Boylston; their participation in this experiment must not be portrayed as freely chosen.