St. Louis Post-Dispatch, Missouri, August 11, 1907

I thought this article was interesting for this line:

The milkmaid, accidentally vaccinated by her trade, escaped smallpox, and so gained the repute for fresh complexion..

Milkmaids, from their close proximity to cows, would commonly get cowpox at some point, and would then be immune to smallpox. The first smallpox vaccine, introduced by Edward Jenner, was brought about in this way:

In 1796, Sarah Nelmes, a local milkmaid, contracted cowpox and went to Jenner for treatment. Jenner took the opportunity to test his theory. He inoculated James Phipps, the eight-year-old son of his gardener, with material taken from the cowpox lesions on Sarah’s hand. After a mild fever and the expected local lesion James recovered after a few days. About two months later Jenner inoculated James on both arms with material from a case of smallpox, with no effect; the boy was immune to smallpox.