A colonial inoculation experiment has unequal power

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.

Onesimus, enslaved by Cotton Mather, had earlier described an African inoculation method that shaped advocacy during the epidemic.

Jenner transferred material from milkmaid Sarah Nelmes’s cowpox lesion to the eight-year-old boy.

Sarah Nelmes supplied the cowpox material used in the experiment; she should be included in the account of the procedure.

The date marks Phipps’s cowpox inoculation, not the later challenge that tested whether he was protected.

The experiment helped develop a distinct smallpox vaccine; variolation had already been practiced in Asia and parts of Africa.

Morton administered ether while Warren operated on Abbott at Massachusetts General Hospital.