1238
to dull ochre. The enthusiastic but careless employment
of these inexpensive “old hypo fi xing and colouring
baths” proved disastrous for the permanence of many
salt prints.
A better procedure for toning salt prints had already
been proposed in 1847 by P. F. Mathieu, who employed
sel d’or—a complex thiosulfate of gold(I)—to protect
the silver image with a deposit of gold metal, as used
for gilding daguerreotypes since 1840. Encouraged by
Gustave Le Gray’s recommendation in 1850, many
French photographers took to gold-toning, but its
benefi ts were only publicised in Britain much later in
1855, by Thomas Sutton. His energetic advocacy in
the Photographic Journal won over the leading photo-
chemist Thomas Hardwich, who repudiated his earlier
recommendation of the ‘old hypo bath,’ in the second
edition of his Manual of Photographic Chemistry in
- In the same year, the Photographic Society set up
a committee with the remit “to take into consideration
the Question of the Fading of Positive Photographic Pic-
tures upon paper.” This so-called “Fading Committee”
recommended—though not unanimously—that gold
toning be employed. The ‘old hypo bath’ was not fi nally
discredited until ca. 1858. By then, the fading of salt
prints had become a chronic problem; for instance, those
printed by Nicholaas Henneman from 1844 onwards,
for Talbot’s publication The Pencil of Nature, suffered
from the use of ‘old hypo’ at the Reading Establishment,
where inadequate washing procedures were occasioned
by the intermittent and impure water supply.
Greater success with salted paper printing was en-
joyed by the circle of Scottish amateur photographers
based in St. Andrews, and by their professional brethren
in Edinburgh, David Octavius Hill and Robert Adamson.
Between 1843 and 1847 this uniquely fruitful collabo-
ration produced thousands of salt prints of rich color
that survive well today. Edinburgh Old Town was then
affectionately known to the Scots as “Auld Reekie” and
the ingress of the sulfur-polluted atmosphere some-
times caused fading at the margins, but the body of the
print was usually unattacked. The stability of Hill and
Adamson’s salt prints may be attributed to their use
of dilute fi xer and very thorough washing—24 hours
was usual—to ensure complete removal of residual
thiosulfate.
Three other improvements to Talbot’s original for-
mulation for photogenic drawing paper have proved
worthy of note:- The ‘ammonio-nitrate of silver paper’ devised
by Alfred Swain Taylor in 1839, which yielded a
more neutral print color, and was easier to fi x. - The inclusion of sodium citrate in the salting
solution to absorb the chlorine produced pho-
tochemically, which otherwise reversed the
reaction by re-oxidising the silver image; this
became a standard additive to all later printing
out papers. - Immersion in dilute sodium chloride before the
hypo fi xation bath, to precipitate any remaining
soluble silver nitrate, which could otherwise cause
brown stains of silver sulfi de by oxidising the
thiosulfate.
SALTED PAPER PRINT
Benecke, Ernest. Vie de
Gebel Mousir & Il Cataract
du Nil regardant au nord-
Nubie 72.
The J. Paul Getty Museum,
Los Angeles © The J. Paul
Getty Museum.