31 Sackville S^{t <1>}
July 1. 1841

Dear Sir

On the 10^th June I read my paper to the R. Soc^y describing the Calotype process, and shortly after I sent you some remarks on it with specimens of the substances employed. ^<2> I hope you received them, and if you try the process and find any difficulties (as some of my friends have done) I shall be happy to add any further explanations. On my return to Town from a little rustication, I found that the Council had rejected the paper from the Transactions. On enquiring the cause, I was told that they understood the paper to have been printed elsewhere previously to its being read to the Society. ^<3> A very erroneous supposition; and it is greatly to be lamented that in a body like the Royal Society such a system of secrecy , or mystery, should prevail, as not to give the author of a Paper any intimation whatever of such an objection being made, nor ask him for any explanation. D^r Roget ^<4> whom I have found in Town (most of the others being dispersed for the summer) is of opinion that the Council are in error & ought to reverse their decision, and that it would be well if I wrote them a circular letter pointing out the mistake – A most irksome task & which I hesitate to undertake. The result is, that any future papers of mine on the same subject will appear in the Transactions, as members without a head – acephalous – hardly intelligible: or rather, I shall do better to abstain from writing any.

I am sorry that the body whose office it is to encourage science in England, encourages it in this way – but such is the case

All the photographs you sent me, done with vegetable juices, were positive. Is this the case universally?

Yours very truly
H. F. Talbot

It is a nice point to determine which is the most sensitive to light, my Calotype paper, or the Daguerreotype improved by Claudet’s process. ^<5> I am sensitive to simple moonlight; he has not yet made the trial, which I throw out as a challenge to all photographers of the present day: viz. that I grow dark in moonlight before they do.

Sir J. Herschel Bar^t
Collingwood
Hawkhurst
Kent

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Notes:

1. 31 Sackville Street, London residence of the Feildings, often used as a London base by WHFT.

2. WHFT read before the Royal Society on 10 June, ‘An account of some recent improvements in Photography’. Only an abstract was published in the Proceedings of the Royal Society, v. 4 no. 48, 1841, pp. 312–315. WHFT reprinted the full text of his article in leaflets, first as The Process of Calotype Photogenic Drawing in 1841, and again in 1845 under the title The Process of Talbotype (formerly called Calotype) Photogenic Drawing.

3. WHFT published two articles in February on the Calotype: ‘Calotype (Photogenic) Drawing’, The Literary Gazette and Journal of belles lettres, science and art, no. 1256, 13 February 1841, p. 108; and ‘Fine Arts: Calotype (Photogenic) Drawing’, The Literary Gazette and Journal of belles lettres, science and art, no. 1258, 27 February 1841, pp. 139–140.

4. Dr Peter Mark Roget (1779–1869), scientific writer.

5. Antoine Françoise Jean Claudet (1797–1867), London; French-born scientist, merchant & photographer, resident in London, used the method of fuming his daguerreotype plates with chlorine as well as iodine, increasing the sensitivity. This method, combined with his use of the improved lens invented by Joseph Petzval (1807–1891), enabled him to dramatically shorten the time of exposure for sitters in his portrait studio.