From Joseph Fayrer   17 June 1874

16 Granville Place | Portman Square | London W

17 June 1874

Dear Sir

My friend Dr Lauder Brunton told me today that he thought you would be glad to have some Cobra poison for an experiment1   I therefore take the liberty of enclosing you a small quantity of that very active agent. It has recently been sent to me from Calcutta—and is quite recent. I think you will find 14 of a grain dissolved in water injected under the skin sufficient to destroy a rabbit. That quantity injected into the jugular vein of a large rabbit today killed a large rabbit in 60 Seconds. A more diluted solution will probably answer the purpose you require.

I daresay you know that this is a subject I have been investigating in India—and since I returned to England have been continuing the enquiry in conjunction with Dr Brunton2

Believe me Your’s very faithfully | J. Fayrer.

1
Thomas Lauder Brunton had assisted CD with some of his experiments for Insectivorous plants, particularly in determining the digestibility of various substances using digestive fluids in the laboratory (see, for example, letter from T. L. Brunton, 28 February 1874). There is no mention of cobra poison in CD’s most recent known letter to Brunton of 25 May [1874].
2
Fayrer had written a book on venomous Indian snakes and their poison (Fayrer 1872) and had been working on the physiological action of snake poisons with Brunton. They had already published one paper on the subject (Brunton and Fayrer 1873–4).

Please cite as “DCP-LETT-9497,” in Ɛpsilon: The Charles Darwin Collection accessed on 5 June 2025, https://epsilon.ac.uk/view/dcp-data/letters/DCP-LETT-9497