Mary A. Groff (1850-1928) was born in Baltimore, Maryland, and died in Philadelphia, Pennsylvania. She worked as a schoolteacher in Baltimore and then Washington, D.C., where she moved sometime prior to 1875. By the mid-1880s she had moved to Philadelphia where she taught music and language in schools and privately. There she was also a member of the executive board of the Free Library of Economics and Political Science. Groff, her two brothers, and her two sisters lived together in the same household in Philadelphia for most of their adult lives. In 1886 she ordered a copy of Science and Health with Key to the Scriptures.

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