SOURCE: “Early American Immunology: As Formulated by the Reverend Cotton Mather of Boston, 1725,” in Medicine in America: Historical Essays, Baltimore: The Johns Hopkins Press, 1966, pp. 252-58.

In the following essay, originally published in 1954, Shryock argues the importance of Cotton Mather's medical writing as the sole example of germ theory in eighteenth-century American writings.

Little has been written about medicine as it existed in the English-American Colonies prior to about 1750. Yet European medicine was practiced in these Colonies for well over a century before that time. The reasons for this neglect of early Colonial medicine are obvious enough. American physicians of that period received no formal training, the profession was unorganized, and there were no such medical institutions as schools, libraries, or hospitals. The population was small; in 1720, for example, only four towns could boast of as many as 5,000 inhabitants. The few men who were at all learned in...