84, rue Bonaparte
Paris – 5 7bre 1868
Sir
A thousand pardons if I take the liberty of addressing the present to you. – At the Great Exhibition of 1851 I had the pleasure & honour of being introduced to & making your personal Acquaintance, & at the same time you were kind enough to address a Letter to me which has always been precious to me & kept as such–<1>
I am desirous of engraving on Steel by means of the Talbotype – looking upon it as Certain that in a short time everything in the shape of impression will be done with printers black, inasmuch as everything that is now done, particularly on albumenous paper [illegible deletion] does not last–<2>
Having consulted & examined with attention all the systems of engraving by light on Metals, I have found that your basis of Bichromate of Potasse is without doubt the best, & everybody who now occupies himself, whether with heliographie on Metal – or on stone takes for basis your pos process – the Bichromate of Potash is invariably preferred to the Judah Pitch indicated by Mr N Niepce. <3> –
If, since your communication to the Institute,<4> you have made any fresh researches as to the mode of proceeding on Steel, and have obtained favourable improvements, I I trust you will not deem me indiscreet if I beg you to make them known to me – you will do me the greatest possible pleasure, for it is on Steel & with your process that I wish to make my trials –
It is a pity that the “Mordant” which you indicate as the only one suitable is so high in price.–<5> Your kind advice will be very precious to me & most gratefully acknowledged. – Pray accept the assurance of my highest esteem
Martens
Artiste
Notes:
1. Letter not located.
2. Charles Piazzi Smyth, the Astronomer Royal for Scotland, used albumen prints and a photoglyphic engraving together in his offiical report on his expedition to Teneriffe. In his introduction, in tribute to WHFT, he explained: "to the inventor alike of photography and photoglyphy, it must be comparatively indifferent by which of his two methods these unusual Teneriffe landscapes are introduced into this book, though to readers in a future century it may make a great difference; for the photoglyph must last as long as the paper it is printed on, but the photography may go the way of some of those beautiful specimens exhibited last year in the International Exhibition, and which faded before the eyes of the nations then assembled." Smyth, Report on the Teneriffe Astronomical Experiment of 1856, Addressed to the Lord's Commissioners of the Admiralty (London: printed by Richard Taylor and William Francis, 1858), pp. vi-vii. As he predicted, the albumen prints in copies of this Report have long since faded, but the sole photoglyphic engraving is apparently as strong as the day it was made.
3. Joseph Nicéphore Niépce (1765–1833), photographic inventor who had achieved photographic images on pewter plates coated with light sensitive asphalt. Controversy remains whether his real goal was individual images, or a planographic printing plate.
4. Académie Royale des Sciences de l'Institut de France. In 1858, WHFT chose another path for publishing the news of photoglphic engraving in France, his friend l'Abbé Moigno's journal Cosmos, v. 3 no. 2, 1858, pp. 536-543. see Doc. No: 07419.
5. In his 1852 patent for photographic engraving, WHFT specified bichloride of platina (platinum perchloride) as a mordant, or etchant, an expensive chemical commonly used in the printing industry. This was carried over into his 1853 French Patent. But in his 1858 photoglyphic engraving patent, WHFT recommended the much cheaper perchloride of iron, which produced very similar results. This was soon adopted thoroughout the entire printing industry, usually without credit to WHFT. It seems that Martens was relying on very early accounts of WHFT's processes.