London
122 Regent St <1>
29th Nov 1850
To H F Talbot Esqr
Sir
When I last wrote to you I intended to write again in a few days but the subject of my intended letter not being urgent I postponed writing it I had then in view some experiments I had made on “Negatives” submitted to the action of Caustic Potash. You may remember that waxing a negative with a very hot iron gives rise to somewhat opaque spots that destroy the beauty of the positive proof I think you have a fine negative of one of the young Prince’s spoiled in that way.
Mr Calvert Jones <2> brought me a negative thus injured, of a doorway, with a figure resting. It occurred to me that Potash would perhaps improve it & I at once tried an experiment which appeared to be a failure, for though the “heat spots” had disappeared, the paper had become red in colour. I strengthened the Potash solution & continued the action until the colour also disappeared. The negative now looked worse than ever, its back & face were of a dirty brown tint & on trying to look through it I found all its transparency gone. Mr Calvert Jones & Henneman <3> thought it a complete failure but I did not as I had long ago made experiments of a similar character for another purpose.
I now after washing it immersed it in dilute nitro-muriatic acid; in an instant the paper whitened & resumed its transparency giving a good black & white picture indeed in a far better state than when I commenced it looked blacker & had more definition took the wax readily and, (what was aimed at) was free from the “heat spots”
The Potash had acted on the size & wax, saponifying the latter & decomposing the former; hot water took away the soap leaving some rather opaque organic substances, which stained the paper, these at length gave way to the nitro-muriatic acid which probably dissolved them out or acted by simply bleaching them without removal.
The negative was much whiter than at first yet it lost none of its detail Originally about 6 inches long it was now only five The contraction of the image doubtless gave the increased blackness I have already spoken of and caused the apparently improved definition.
I also think the paper itself was improved by a kind of gelatinizing effect upon the fibres rendering the mass more uniform at the expense of its former fibrous character.
I was so much pleased with the perfect success of an experiment intentionally planned that I thought you would also be pleased to have some account of it as an evidence of progress though in only a slight matter.
I am Sir Your most obedt Servt
T. A. Malone
P.S
I have some other subjects for which I cannot in this note find room. I must again promise to write soon not fixing a day as my health lately has indisposed me for mental exertion.
T A M.
[envelope:]
H F Talbot Esq
Lacock Abbey
Chippenham
Notes:
1. 122 Regent Street, London: base of Nicolaas Hennemans’ Talbotype or Sun Picture Rooms, later the firm of Henneman & Malone, photographers to the Queen.
2. Rev Calvert Richard Jones (1802–1877), Welsh painter & photographer.
3. Nicolaas Henneman (1813–1898), Dutch, active in England; WHFT’s valet, then assistant; photographer.