Mary D. Porterfield (1831-1915) was born in Erie, Pennsylvania, and died in Waterloo, Iowa. She was a student of Mary Baker Eddy's, completing the Primary (1886) and Normal (1887) classes. She joined the Christian Scientist Association on July 1, 1885. On April 4, 1896, she joined The First Church of Christ, Scientist, in Boston, Massachusetts, and was a member until her passing. Porterfield was a Christian Science practitioner and teacher listed in the directory of The Christian Science Journal from about 1893 until 1910.

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