# Charlotte Elvira Pengra

May 30, 1875 - February 7, 1916

Born on May 30, 1875 in Juda, Wisconsin, the eldest of 5 children.
Her father was apparently a fairly well-to-do farmer
(later mayor and bank manager).
Received her A.B. in Mathematics at the University of Wisconsin in 1897, and
in 1901 became the first woman to receive a Ph.D. in mathematics at the University of
Wisconsin-Madison, and the third Ph.D. overall from that department. Her
thesis about conformal representation of plane curves was entitled "On Functions Connected with Special Riemann Surfaces, In Particular Those For Which P Equals 3, 4, and 5."

Taught high school at Fox Lake, WI and Sparta, WI and Elgin, Illinois.
In 1904 she married Arthur Robert Crathorne (PhD, Math, Göttingen, 1907).
They had three children, the 1st in Göttingen, Germany,
the 2nd in Brodhead, Wisconsin, and the 3rd in Champaign, Illinois
where they eventually settled. Arthur Crathorne seems to have spent
the rest of his career teaching at the University of Illinois.

Charlotte died in 1916, of breast cancer, at her parents' home in
Brodhead, Wisconsin. She was 40 years old.

### References

- Personal correspondence from Preston Pengra Briggs
- University of Illinois Archives
- Author Profile at zbMath
- Mathematics Genealogy Project