From John Barlow   Nov. 14th. 1864

the second distinction: the Rumford Medal is an award bestowed by the RS every alternating year for ‘an outstandingly important recent discovery in the field of thermal or optical properties of matter made by a scientist working in Europe’, second only to the Copley Medal. Tyndall received the Rumford Medal in 1864 ‘for his work on the Absorption and Radiation of Heat by Gases and Vapours’ (‘November 30, 1864. Anniversary Meeting’, Roy. Soc. Proc., 13 (1864), pp. 494–520, on pp. 515–7). By ‘second distinction’, Barlow was referring to Tyndall having previously been awarded, in 1853, the RS’s Royal Medal ‘for his paper on diamagnetism and magne-crystallic action, published in the Philosophical Magazine in 1851’. However, Tyndall declined the award, on account of some council members doubting his priority in the original research and insisting that Julius Plücker (1801–68) deserved the award instead (see letter 0828 in I. Hesketh and E. Sera-Shriar (eds), The Correspondence of John Tyndall, Volume 4: The Correspondence, January 1853–December 1854 (Pittsburgh: University of Pittsburgh Press, 2018); and R. Jackson, ‘John Tyndall and the Royal Medal that was never struck’, Notes and Records: The Royal Society Journal of the History of Science, 68 (2014), pp. 151–64).

obtain the highest: Tyndall never did receive the RS’s Copley Medal, which was bestowed every year for ‘outstanding achievements in research in any branch of science’.

Mrs Barlow: Cecilia Anne Barlow (née Law, d. 1868), the daughter of a wealthy member of Parliament. They were married in 1824.