Ɛpsilon

To John Tyndall   1 March [1871]1

Down. | Beckenham | Kent. S.E. [6 Queen Anne Street]

March 1

My dear Tyndall

I saw Dr. Ogle, who is a most acute observer, & told him of your suggestion, & he will keep it in mind, in reference to the less hairy races of man & the lower animals—2

He is very anxious for information on one point, & as it is closely connected with your work, I have thought you could forgive me for troubling you.—

Does your glycerine &c respirator deprive odorous substances of their smell.—3 I neglected to ask what sort of substance, but I think from the tenour of his remarks, solid substances, such as camphor, musk, rubbed brass wd be most useful to him; but I daresay he wd. care about volatile oils or any odorous matter.

He is much perplexed with some physiological results,—as for instance the relation of colour to the tissues supplied with olfactory nerves, & of differently coloured substances absorbing with different degrees of power odours.4

A brief note, which I cd. communicate to Dr Ogle, wd. greatly oblige me.—

Yours very sincerely | Ch. Darwin

(I return home tomorrow morning)5

1
The year is established by the address, with ‘Bromley’ crossed out and ‘Beckenham’ added by hand, a form that CD used from April 1869 to May 1871, and by CD’s reference to his returning to Down the next day. CD was in London from 23 February to 2 March 1871 (see ‘Journal’ (Appendix II)).
3
For more on the respirator Tyndall had devised, see the letter from John Tyndall, 23 February [1871].
4
In Ogle 1870, pp. 277–86, Ogle discussed the relation between pigment and the absorption of odours and suggested that a keen sense of smell was associated with the presence of dark pigment in the olfactory area.
5
See n. 1, above.

Manuscript Alterations and Comments

0.1 Beckenham] before del ‘Bromley.’
1.2 it] interl
1.2 the less hairy] interl above del ‘other hairless’
2.2 for] interl
3.4 matter] after del ‘subs’
7.1 (I … morning)] added above address

Please cite as “DCP-LETT-7524,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-7524