February 22, 1862 - October 15, 1917

Ruth Gentry grew up in Indiana and received her A.B. degree at Indiana State Normal (now Indiana State University) in 1880. After ten years of teaching at preparatory schools, she earned a degree in mathematics from the University of Michigan in 1890. She spent the following year as a Fellow in Mathematics at Bryn Mawr, then became the first mathematician and the second recipient of the Association of College Alumnae European Fellowship, which she used in 1891-92 to attend lectures at the University of Berlin (but was not allowed to enroll for a degree). After a further semester attending mathematics lectures at the Sorbonne in Paris, Gentry returned to Bryn Mawr to become one of Charlotte Scott's first two graduate students. She received her Ph.D. in 1896 on the topic "On the Forms of Plane Quartic Curves." As she writes at the beginning of this thesis:

Many papers dealing with curves of the fourth order, or Quartic Curves, are to be found in the various mathematical periodicals; but these leave the actual appearance of the curve as a whole so largely to the reader's imagination that it is here proposed to give a complete enumeration of the fundamental forms of Plane Quartic Curves as they appear when projected so as to cut the line infinity the least possible number of times, together with evidence that the forms presented can exist.

Gentry taught at Vassar College from 1896 until 1902, where she was the first mathematics faculty member to hold a Ph.D. degree. She was promoted to associate professor in 1900, but left Vassar two years later to become the associate principal and head of the mathematics department at a private school in Pittsburgh, Pennsylvania, a position she held until 1905. After that she spent some time as a volunteer nurse and traveled in the United States and Europe, but she became increasingly ill and died at the age of 55. She was a member of the American Mathematical Society from 1894 until her death in 1917 in Indianapolis, Indiana.

- Patricia Kenschaft. "The Students of Charlotte Angas Scott," Mathematics in College, Fall 1982, 16-20.
- Della Fenster and Karen Parshall. "Women in the American Mathematical Research Community: 1891-1906," The History of Modern Mathematics, Vol. III (Eberhard Knobloch and David Rowe, eds.), 229-261.
- Whitman, Betsey S. "Women in the American Mathematical Society before 1900," Association for Women in Mathematics Newsletter, 13(4) (July/August 1983), 10-14.
- 1920 Register of Alumnae of Bryn Mawr College
- Mathematics Genealogy Project
- Author Profile at zbMath
- Biography at the MacTutor History of Mathematics Archive