Our Profr of Chemistry Mr Connell <4> assisted Major Playfair and me in our first attempts; Our materials were purely, and carefully washed and applied, but we could get nothing like a good picture.
Major Playfair has since tried it repeatedly and patiently by himself, & has drawn up the enclosed note of what he did,<5> which I send you with a specimen of the paper so prepared by the first part of the process. Dr Adamson who is a good Chemist, & successful with the Daguerreotype has also failed, and says that the Paper when ready for the Camera became black in the dark.
We tried the specimen of Paper your previously sent me, but not with any better success. Does any thing depend on the strength of the acetic acid? We used at one time crystallised nitrate of silver & at another time Lunar Caustic. <6>
The Iodide of Potassium & Gallic Acid were prepared by Dimond & by Holborn, and were doubtless pure. You will oblige me greatly if you could send me a specimen of a Negative Picture and of the Positive one taken from it.
If you can help us out of these difficulties we shall follow minutely your instructions.
I am Dear Sir, Ever Most Truly yrs
July 26th 1841
H. Fox Talbot Esqr
1. Such failure was not unusual. For an understanding of the hidden complexities of the simple sounding Calotype process, see Roger Taylor and Mike Ware, "Pilgrims of the sun: The chemical evolution of the calotype," History of Photography, v. 27 no. 4, Winter 2003, pp. 308-319.
2. Sir Hugh Lyon Playfair (1786–1861), military & provost of St Andrew’s University. He had mastered the Daguerreotype too. The Minutes of the St Andrews Literary and Philosophical Society for the meeting of 3 May 1841 report that ‘Mr Thomas Davidson from Edinburgh exhibited his new and improved Camera Obscura, for taking Daguerreotype drawings, and Portraits – and exhibited numerous specimens executed by Major Playfair and himself.’
3. Dr John Adamson (1809–1870), physician and pioneer of photography. See A. D. Morrison-Low, ‘Dr John Adamson and Robert Adamson: An Early Partnership in Scottish Photography’, The Photographic Collector, v.2, 1983, pp. 198–214.
4. Arthur Connell. Album 6 in Special Collections, Library of University of St Andrews, contains a group portrait entitled “The Chemistry Class taught by Dr Adamson during Professor Connell’s illness”.
5. Enclosure not located.
6. Silver nitrate. Alchemists called silver Luna, after the moon, and lunar caustic was a common form of silver nitrate found in commerce - it was formed into sticks and used to cauterize wounds.