Narragansett newspaper ad from 1892. Caption reads:

PHYSICIANS all over New England who have occasion to prescribe Lager as an invigorator, appreciate the fact that the lager brewed at the Narragansett Brewery of Providence, R.I., since its establishment two years ago, has enabled them to obtain a truly pure and decidedly wholesome beer for their patients.
    The Malt and Bohemian Hops used in this Lager are the best that is possible to obtain.
    This, with the purest spring water, scrupulous cleanliness and a most thorough process of fermentation, makes it highly desirable for medicinal purposes.
    Physicians and professional men are cordially invited to inspect the plant and process.