Faraday to George Wilbraham1   7 July 1836

Royal Institution, 7th July, 1836.

Sir, - Though confined to my room by illness2, I have endeavoured to direct such examination of the specimens of Salt you left me, as should be sufficient to give you the information you required. The Salt from Madras was by much the purest. It contains about four per cent. of insoluable matter, principally silica, in grains, and particles of sand and traces of sulphate of lime. The Salt from Calcutta, on the contrary, contains eighteen and a half per cent. of insoluable matter, of an argellacious or clayey nature, and more sulphate of lime is found in the solution. This Salt is in a very dirty and foul state.

I do not find any notable proportion of magnesian Salt in either specimen3.

I am, Sir, your very obedient Servant, | W. Faraday.

G. Wilbraham, Esq. M.P. | &c. &c. &c.

1
George Wilbraham (1779–1852, B1). MP for South Cheshire, 1832–1841 and a life member of the Royal Institution. He was chairman of the Select Committee appointed to inquire into the supply of salt in India. Anon (1837) published the report of the committee and also an unofficial report written by Wilbraham.
2
This was Faraday’s problem with his right knee. See Faraday to Daubeny, 13 July 1836, letter 928, volume 2.
3
See ‘Royal Institution Laboratory Notebook, 1830–1861’, RI MS HD 8b, 6 July 1836, p.82 for Faraday’s analysis.

Please cite as “Faraday0926a,” in Ɛpsilon: The Michael Faraday Collection accessed on 29 April 2024, https://epsilon.ac.uk/view/faraday/letters/Faraday0926a