From John Frederick William Herschel July 21, 1856
Collingwood | July 21, 1856
Dear Sir
If you think anything in my letter1 worth printing you are quite at liberty to do so. I would merely add a word or two in a note to the effect that in forcing down the strata2 which still in some degree yielding down the general slope of the ocean bed, they must often be driven over its larger inequalities
in a way very likely to contort and corrugate them and this too, equally whether the softness be that remaining in them previous to their consolidation – or be produced anew by invasion of heat from below producing semifusion and weakening their support.
As the Glacier in its descent will have to be forced over occasional protuberances in its bed its structure (as modified by your causes of lamination) may be expected to bear the traces of this action. The ice of a glacier however does not seem to be a substance very favourable for exhibiting your class of phenomena.
Wishing you much enjoyment in Switzerland.
I remain | Dear Sir | Yours very truly | J. F. W. Herschel.
J. Tyndall Esq
RI MS JT/1/H/93
my letter: letter missing; but see letter 1261.
in forcing down the strata: the phrase is preceded by the symbol ‘ [*’ in Herschel’s handwritten copy, but not in his copyist’s version at the Royal Society (Royal Society Letters 23_175). It is unclear whether Herschel intended to include a footnote, or whether the mark was Tyndall’s to remind him of this striking phrase.
Please cite as “Tyndall1258,” in Ɛpsilon: The John Tyndall Collection accessed on