This guest post from Karen Masters is part of the 2012 Midpoint Series. See all of the posts in the series here.
Mary Somerville (1780-1872) was an innovative and talented science communicator, with an extraordinary (and mostly self-taught) grasp of mathematics in an era when most women had no access to formal education. As a direct result of her work, calculus was introduced to the English-speaking scientific world, the idea of physics (as a single subject containing topics such as optics, thermodynamics and astronomy) was invented, and the term “scientist” was coined to describe people who studied the various sciences.
In 1826 Mary Somerville became the first woman to author a scientific paper published by the Royal Society (which was possible through her second husband’s membership of the society), discussing her work in trying to understand the properties of the UV radiation from the Sun. The success of this work led to her being invited to translate into English Laplace’s last work “Mechanique Celeste”, which was already at the time considered to be the most significant advance in understanding celestial mechanics (applying the “new” mathematics of calculus to solve several previously intractable problems) since Newton’s “Principia”. Mary took four years in the translation, but instead of a direct version of the book, significantly reorganized how it was presented to make it more lucid, and even in some cases, used her own proofs rather than Laplace’s. This translation is credited with bringing the “continental methods” of calculus to English-speaking students of Mathematics. And its introduction was published separately for a public audience, becoming so popular that it remained in print for 50 years!
Mary’s next project was “The Connexion of the Physical Sciences” (1834), a book which aimed to bring to popular (and female) audiences an overview of how universal laws of physics could be used to explain many branches of science (e.g. matter, optics, electricity, magnetism and astronomy). This book was acclaimed by scientists and general readers alike, and made Mary truly famous in her day, selling thousands of copies. It’s basically the invention of the idea of physics as we understand it, and also led to the invention of the term “scientist”.
In the book one of the things Mary explained was that the laws of physics could explain the predictable and stable orbits of the planets. At the time Uranus had just been discovered, and its orbit was known to show discrepancies from predictions. Mary explained this: “Possibly it [Uranus] may be subject to disturbances from some unseen planet revolving about the sun beyond the present boundaries of our system”. Supposedly Adams told Mary’s husband that this line inspired him to “calculate the orbit of Neptune”, although some doubt remains as to this claim. What is clear though is that Mary had the idea, and would have been capable of making the calculation which predicted the existence of Neptune. We can only speculate why she did not.
The fame of these works led to Mary Somerville being one of the first women admitted into the Royal Astronomical Society. At the time female members were against the rules, but the society in 1836 initiated a new rank of “Honorary Member” specifically to be able to admit Mary Somerville and Caroline Herschel (30 years Mary’s senior).
Despite all this I was unaware of Mary’s contribution to science until I started searching for a Google Worthy Woman to write about. I stumbled across her mentioned in the same sentence as the much more famous Caroline Herschel, and was immediately intrigued. I find it interesting (and disappointing) that she is often described in relation to her husband(s) and father. For example the caption to the beautiful portrait, above, in the Scottish National Portrait Gallery says:
Mary Fairfax was the daughter of a naval officer and born in Jedburgh. As was customary for young ladies, she received very little formal education. Yet she taught herself algebra in secret and, as a young wife and mother, she continued to study mathematics. Widowhood at twenty-seven gave her the independence to develop her intellectual interests and her second husband, William Somerville, proved more supportive than her first. Somerville’s particular contribution to nineteenth-century science lay in her powers of analysis and explication rather than original research. She translated Laplace’s ‘The Mechanism of the Heavens’ into English and wrote a bestselling book on physics. After her death, Somerville College in Oxford was named in her honour.
Mary married twice – first to a Captain Samuel Greig, with whom she had two children before he died after 3 years of marriage. By accounts Captain Greig was not supportive of Mary’s study of mathematics, but she continued anyway. As a young widow she had more freedom to suit herself (although also we should point out also two young sons to look after), and when in 1812 she married Dr. William Somerville he turned out to be much more supportive of her work. She had four more children (all girls) with Dr. Somerville, who also brought the son of a former marriage to the family. One of her sons died in infancy, and her eldest daughter (who she called “a child of intelligence and acquirements far beyond her tender age”) died at age 10. Her eldest remaining son became a barrister and scientist, and Mary lived with her 3 adult daughters (who never married) until she died.
— Karen Masters