Ɛpsilon

From George Gabriel Stokes   22nd May 1861

Lensfield Cottage Cambridge | 22nd May 1861

Dear Dr Tyndall,

I have only time at present just to say that there is no doubt reflection on the surfaces of the globules of water would produce the effect you describe.1 To you who had seen the thing the explanation may have appeared obvious; but when I read of precipitation I pictured to my mind’s eye moistened ends and a few sparse globules. I think the word dim or dimness introduced in correcting the proof2 would lead the reader instantly and infallibly to draw in his mind a correct picture of the phenomenon, and then there can be no question that the assigned cause is at least a vera causa whether or not it be the actual cause which produced the difference in the results.

Yours very truly | G. G. Stokes

RI MS JT/1/S/223

RI MS JT/1/TYP/4/1372

1

the effect you describe: see letter 1782, but this also implies that there may be a missing letter from Tyndall.

2

dim or dimness introduced in correcting the proof: on the assumption that this relates to the precipitation of water, Tyndall did not introduce the word ‘dim or dimness’ as suggested.

Please cite as “Tyndall1784,” in Ɛpsilon: The John Tyndall Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/tyndall/letters/Tyndall1784