44 Queen Ann S^{t <1>}
Friday

Dear Sir

As I understand that you exhibited some photogenic drawings at the R.S. ^<2> last night, allow me to ask if it is your intention to publish at present any account of your method of “washing out”? ^<3>

My motive for asking is, that in that case I could take the opportunity of making known my method of “fixing”, either separately, or in a joint communication with yourself to the R.S. if you should be willing to adopt that suggestion–

At present however, I merely wish to be informed whether you are intending to describe your process, or to wait a little.

Believe me Yours most truly
H. Fox Talbot

P.S. concerning “washing out” vide Sir H. Davy in the 1^st vol. of journal of R. Institution. ^<4> He could not effect it.– perhaps nothing else will answer than your ingenious recipe. Did you receive the transparencies?

Sir J. Herschel Bar^t
Slough

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Notes:

1. London.

2. Herschel exhibited several examples of his photographs at the Royal Society of London, see Doc. No: 03801.

3. Herschel’s method of using ‘hypo’ as it came to be known, differed from WHFT’s method of fixing or stabilising the prints. The use of hyposulphite washed the remaining silver from the print, and was in turn washed away by water. WHFT’s method of stabilising the prints in potassium rendered the image stable but subject to fading over time.

4. Sir Humphry Davy (1778–1829), chemist and Thomas Wedgwood (1771–1805), ‘An Account of the Method of copying Paintings upon Glass, and of making Profiles, by the agency of Light upon Nitrate of Silver. Invented by T. Wedgwood, Esq. With Observations by H. Davy’, Journals of the Royal Institution, v. 1 no. 9, 22 June 1802, pp. 170–174.