Faraday to William Robert Grove   1 November 1845

Royal Institution | 1 Novr. 1845

Dear Grove

I am ashamed to say that I forgot until now to thank you on my wife's part for the birds you sent her but I have been very busy & am so still - & the results or some of them you shall hear of shortly1[.]

Ever Truly Yours | M. Faraday

W.R. Grove Esq | &c &c

1
This was Faraday's discovery of the magneto-optical effect, that the state of polarisation of light could be changed by a magnet when the light passed through a piece of heavy glass. He made this discovery on 13 September 1845 (Faraday, Diary, 13 September 1845, 4: 7504) following his failure to find a change in light passing through a transparent dielectric (see letter 1767 and note 3) and on which he had been working since. See James (1985), 145-7. The transparent bodies which he found displayed this property he quickly called "dimagnetics" (Faraday, Diary, 18 September 1845, 4: 7576) in analogy with dielectrics, ibid.,7570.

Bibliography

JAMES, Frank A.J.L. (1985): “'The Optical Mode of Investigation': Light and Matter in Faraday's Natural Philosophy” in Gooding and James (1985), 137-61.

Please cite as “Faraday1779,” in Ɛpsilon: The Michael Faraday Collection accessed on 29 April 2024, https://epsilon.ac.uk/view/faraday/letters/Faraday1779