Lorna Swain's father was Edward Swain (born Ropsley, Lincolnshire about 1853) who was a solicitor. Her mother was Mary Isabella Victoria Swain (born at St Paul's, London about 1865).
Lorna Swain was educated at South Hampstead High School in London. From there she won a scholarship to study at Newnham College, Cambridge and she began her studies in 1910. In 1913 she graduated with a First Class honours degree in mathematics and was appointed to an assistant lecturer post at Newnham College with the start of the appointment delayed for a year to allow her to spend a year in Göttingen.
However 1914 was not the best of year to begin research in Germany. Shortly after she arrived there war broke out and she hurriedly returned to England. Her mathematical books and papers fared less well and remained interned for several years before eventually being returned.
Swain's mathematical interests were in fluid dynamics so, as Göttingen was out of the question, she went to Manchester to work with Horace Lamb. While in Manchester she published her first paper, a joint paper with Lamb. As planned, she returned to Newnham College in 1915 to take up her lecturing post. However World War I again affected her career since she now undertook war work at the Royal Aircraft Establishment.
The war work she undertook was related to her expertise in fluids, and she worked on problem of vibration of propellers of aircraft. Her work was written up jointly with H A Webb and appeared as a Report of the Advisory Committee for Aeronautics in 1919.
In 1920 Swain was appointed Director of Studies at Newnham College. With heavy teaching and administrative responsibilities she had less time to undertake research but she did publish an important work on motion through a viscous fluid in 1923 in the Proceedings of the Royal Society.
Kennedy describes her commitment to teaching and education in  as follows:-
It was one of her guiding principles to do everything she could to encourage the study of mathematics not only in her own College but generally among women. For this reason she was an active member of the Mathematical Association and served on their committee to investigate the teaching of applied mathematics. ... She felt that school work could foster or spoil a gift for mathematics and that it was of the first importance that girls should have good teaching. Her own work, she thought, could contribute to the supply of teachers... all her students know how carefully she arranged the work for each individual, giving extra help herself when she thought it necessary.
In 1926 Lorna Swain was promoted to College Lecturer and she then had the opportunity to give advanced courses on hydromechanics and dynamics. A years study leave in 1928-29 allowed her to spend the year at Göttingen that the war had robbed her of earlier. This was a time when she was able to undertake concentrated research and another important work On the turbulent wake behind a body of revolution was published in 1929.
Lorna Swain is described in  as:-
... unassuming, reserved in manner, often silent, a singularly faithful friend. Her former pupils were sure of her interest and encouragement in their careers, of a warm and sincere welcome when they visited her, of prompt and valuable advice when they consulted her.
Her death at a young age took away someone at the height of their teaching and research powers:-
Her wisdom and influence were increasing, her powers of mind were still expanding, when she was overtaken by illness and death. It would be idle to guess what more she might have done if she had lived; it is certain she contributed worthily to mathematical education and to mathematical thought.
Article by: J J O'Connor and E F Robertson