Dear Tyndall,
You will find in page 506 et seq. an acc[oun]t of the experiments in Jamaica on Solar & Terrestrial Radiation at different heights in the Atmosphere,1 which I named to you.2 They were very decisive in character, and might be repeated with ease & with great advantage by the travellers of the Alpine Club,3 either in the Alps or elsewhere. The same fact, ‘the increased effect of radiation’4 is found in the high latitudes, when compared as favorably as it may be with radiation in the Tropics: & probably due t[o] the same cause, the smaller portion of atmosphere thro' which the rays have to pass, the atmosphere acts as a fog.
That the height of the atmosphere is considerably greater at the equator than at the Poles is probable from the effect of the rotation of the earth. The same cause which produces the flattening of the one at the Poles, will produce a greater flattening of the other.
Having a few copies of the volume left, I will ask you to keep the one I send.
Sincerely yours | Edward Sabine
March 12th, 1860
RI MS JT/1/S/18
RI MS JT/1/TYP/4/1313
You will find in page 506 et seq. an acc[oun]t of the experiments in Jamaica on Solar & Terrestrial Radiation at different heights in the Atmosphere: refers to Sabine’s book An Account of Experiments to Determine the Figure of the Earth (London: John Murray, 1825).
which I named to you: not identified.
the Alpine Club: mountaineering club founded in 1857. Tyndall had joined in 1858.
“the increased effect of radiation”: the source of this exact reference is unknown, but Sabine was likely referring to Tyndall’s experimentation on the effect of radiation on water vapour and carbon dioxide.
Please cite as “Tyndall1689,” in Ɛpsilon: The John Tyndall Collection accessed on