Spezia2 9th April 1863
Dear Dr Tyndall
What a wonderful branch of science you have created by your experiments on the absorption and radiation of radiant heat,3 I cannot tell you how much they have interested me. The vast superiority in absorptive power of the compound gases & vapours over that of dry air and the elementary gases, and the enormous increase produced by tension, gives an entirely new view of the energy of the compound molecules of aëriform matter. The discovery of the compound nature of perfumes4 seemed to be the very limit of molecular action, but even that is surpassed by Dynamic absorption and radiation the whole of which is truly marvelous, for although the quantities of vapour are minute beyond imagination, the experiments give the conclusion that they and their molecules have as true an existence as the objects around us. I shall only add that you make it clear that one might live very comfortably in Mercury if his atmosphere had enough of aqueous vapour
Accept my best thanks and | Believe me truly yours | Mary Somerville
RI MS JT/1/S/80
Mary Somerville: Mary Fairfax Somerville (1780–1872), a Scottish science writer and polymath, mathematician, and astronomer. Somerville, who was largely self-taught was, alongside Caroline Herschel, nominated as one of the first female members of the Royal Astronomical Society. She had married in 1804 and was widowed in 1807. Her status as a widow gave her a limited financial independence as well as more social freedom than she would have otherwise enjoyed, which allowed her to seek out teachers and other scholars of mathematics. In 1812 she remarried, and her husband William Somerville, an army doctor, was supportive of her studies. She made connections among the mathematical and scientific community in London, and, following a visit in 1817–8, also on the continent. Her first published work appeared in 1821, but it was her work popularizing Laplace’s five-volume Mécanique céleste (1798–1827) describing his nebular hypothesis which really brought her to notice. She consulted with John Herschel, Augustus De Morgan, and Charles Babbage during the preparation of this work. Her second book On the Connection of the Physical Sciences (1834) brought her into contact with Faraday, Lyell, Whewell, Ampère, and Becquerel. It went through nine editions in her lifetime, and appeared in American, French, Italian and other languages. Somerville was recognised and received awards by many scientific organizations. When John Stuart Mill organized a petition to Parliament to give women the right to vote, Somerville was among the first to sign (ODNB)..
Spezia: La Spezia is a city on the west coast of northern Italy.
your experiments on the absorption and radiation of radiant heat: by this time Tyndall had published several papers on the absorption and radiation of heat, which Tyndall may have sent her copies of: J. Tyndall, ‘On the Absorption and Radiation of Heat by Gases and Vapours, and on the Physical Connexion of Radiation, Absorption, and Conduction’, Phil. Trans., 151 (1861), pp. 1–36; J. Tyndall, ‘On the Absorption and Radiation of Heat by Gaseous Matter. Second Memoir’, Phil. Trans., 152 (1862), pp. 59–98; and J. Tyndall, ‘On the Relation of Radiant Heat to Aqueous Vapour’, Phil. Trans., 153 (1863), pp. 1–12.
perfumes: Somerville is referring Tyndall’s second memoir (the 1862 paper in n. 3), in which he discussed the measurement of scents.
Please cite as “Tyndall1995,” in Ɛpsilon: The John Tyndall Collection accessed on