Bertha Swirles (Lady Jeffreys), (22 May, 1903 - 18 December, 1999) carried out research on quantum theory, particularly in its early days.
She was associated with Girton College, University of Cambridge, as student and Fellow, for over 70 years.
Bertha Swirles was born in Northampton in 1903 attended Northampton School for Girls and then went up to Girton, in 1921, to read Mathematics, graduating with first class Honours. She became a research student of Ralph Fowler, one of a distinguished company of his students that included Paul Dirac and Subrahmanyan Chandrasekhar.
By the time she was awarded her doctorate (in 1929) she was an Assistant Lecturer in Manchester. This was followed by similar appointments in Bristol and at Imperial College, London, and then in 1933 she returned to Manchester as a Lecturer in Applied Mathematics. Douglas Hartree at Manchester was extremely sorry to lose such a valued colleague when she returned to Cambridge in 1938, to an Official Fellowship and Lectureship in Mathematics at Girton.
In Cambridge, Bertha Swirles continued to publish important papers on quantum theory, but her most widely known publication is the enormously influential text Methods of Mathematical Physics, written with Harold Jeffreys, whom she had married in 1940. This was first published in 1946 and, after many editions and revisions, it was reprinted in 1999 with a delightful picture of Bertha and Harold on the back cover.
It has educated many generations of students and is still a recommended text for several undergraduate mathematics courses in Cambridge today.
Subsequently her research interests broadened to include seismology in collaboration with her husband, who was by then Plumian Professor of Astronomy at Cambridge.
She felt an immense loyalty to Girton and played a very active role there, holding a large variety of college offices at various times, including that of Vice-Mistress from 1966 to 1969. Not suffering fools gladly made Bertha Jeffreys seem a little formidable to some. She set the highest standards for herself and expected others to do the same.