**Gertrude Blanch** was a Polish born American mathematician who did pioneering work in numerical analysis and computation.

- Gertrude Kaimowitz, as she was then called, took a job as a clerk.
- Gertrude decided to give up her job working for a hat dealer so that she could concentrate on her studies but her employer, not wishing to lose such a valuable employee, offered to pay her tuition fees if she continued to work for him.
- This was an attractive offer, so Gertrude continued to work for the hat dealer while studying mathematics.
- She graduated with a B.S. (major in mathematics, minor in physics) from New York University in 1932 and, in February of that year, legally changed her name from Kaimowitz to Blanch.
- Blanch had been awarded her B.S. with distinction and decided to continue to graduate study.
- These transformations had, prior to Blanch's thesis, been studied by a number of mathematicians including J A Todd, Virgil Snyder and H F Baker.
- Blanch published the main results of her thesis in 1937 in the American Journal of Mathematics in a paper with the same title as her thesis.
- After the award of her doctorate, Blanch returned to New York City where she worked for a year as a tutor in Hunter College, replacing a member of the faculty who was on leave.
- Blanch worked on the Mathematical Tables Project from the beginning of 1938 until 1942.
- Blanch got a job with the Electrodata Corporation in Pasadena but only worked for them for a year before she became a senior mathematician at the Aerospace Research Laboratories at the Wright Patterson Air Force Base in Dayton, Ohio.
- Blanch's first published paper on Mathieu functions was published in 1946, before she went to California.
- However, in 1945 the National Bureau of Standards had produced a volume of Tables relating to Mathieu functions which had included work by Blanch.
- Among other papers that Blanch wrote before moving to Wright Patterson Air Force Base were: (with Roselyn Siegel) Table of modified Bernoulli polynomials (1950), On the numerical solution of equations involving differential operators with constant coefficients (1952), On the numerical solution of parabolic partial differential equations (1953) and (with Henry E Fettis) Subsonic oscillatory aerodynamic coefficients computed by the method of Reissner and Haskind (1953).
- In 1967 Blanch retired from her job at Wright Patterson Air Force Base and was honoured with the publication of Blanch anniversary volume (1967), which contained a series of papers by her friends.

Born 2 February 1897, Kolno, Russian Empire (now Poland). Died 1 January 1996, San Diego, USA.

View full biography at MacTutor

Origin Poland, Women

**Oâ€™Connor, John J; Robertson, Edmund F**: MacTutor History of Mathematics Archive