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THE LIVERPOOL AND MANCHESTER PHOTOGRAPHIC JOURNAL. Vol. 1, 1857, p.214
AMATEURS' COLUMN.
PAPER FOR PHOTOGRAPHY.
The sheets, after their final removal from the pack, are hung
across horse-hair lines to dry; from three to five sheets being
suspended together, consequently two only are freely expose to the
atmosphere. How far this condition of things may, influence the
result I am unable to say. It will also be observed that one sheet
is in contact with the horse-hair line, which accordingly leaves a
mark across the centre of the surface of all. sheets so situated.
These marks, however, disappear to the eye during the carrying on of
the subsequent operations. The dry paper, still bibulous, is now
quite ready for sizing.
On my first visit to Kent, where the experiments were carried on,
I made many enquiries about the materials used in sizing, and also
about the amount of boiling to which such materials were submitted;
for I knew that the animal tissues and fibres which were capable of
yielding a gelatinous size, were also capable of furnishing a
different product on the long application of a high temperature. At
Hollingsworth's, formerly Whatman's Turkey Mill," I learnt that the
hoofs and feet of animals, in a fresh or green condition, were
preferred to the dried skins and "pates." commonly employed. The
process was to keep such fresh materials for some days in running
water to cleanse them, then they were carefully boiled with
water, keeping the temperature down as much as possible. The liquid
thus obtained was allowed to settle and cool, when the fat would be
found on the surface, and the heavy impurities at the bottom of the
mass, the intermediate portion being a firm well-looking jelly. This
jelly is diluted with hot water to a consistence ascertained by
experience, and judged of empirically by its apparent viscidity.
Alum, in lump, is then added to the warm jelly in varying
proportions. On this point we had no experience. The paper-maker,
therefore, added as much as he thought would produce a hard
resisting size. The addition of alum in great quantity causes the
paper to have a "rattle" on suddenly pulling the opposite corners of
a sheet held loosely and diagonally. And as the buyers are supposed
to be pleased with this rattle, as affording evidence of the
firmness of the fabric, the paper often gets more alum than the
conditions for perfect sizing demand. The alum is found to vary very
much in quality, but the best kind is of course to be selected. The
size, then, consists simply of animal jelly (which is an imperfectly
understood substance or mixture of substances) and alum. Coarser
sizing materials may contain lime or salt, but these are avoided by
good paper-makers. The lime, when present, has been used to remove
hair from the skins, and the salt to check putrefaction. This, one
thing is certain, that the best paper ever made for the Talbotype
process was made at "Turkey Mill," where the size is prepared as
above related. This paper, ream by ream, gave, as a rule, fine close
black negatives; and it could be made sensitive over night with much
stronger solutions of gallo-nitrate than are now recommended. The
development could be deferred until the same hour the next night. It
could fully be depended upon for twenty-four hours even, be it
remembered, when washed over with comparatively strong solutions of
gallo-nitrate.
This paper was used successfully by the Rev. Calvert Jones, about
1844, at Malta, in very hot weather, and also in the East by the
Rev. Mr. Bridges. It is strange to relate that such paper has
never been obtained since, even from the same mill, and that
is why I dwell so much upon it at this moment. Could we get such
paper again .with certainty the Talbotype would take a new start.
The only thing that could compete with it. would be the transfer
process applied to collodion, but that will always be a delicate, if
not a difficult operation for the amateur to perform while on a
tour. I trust these "jottings" of mine may assist in bringing
about a good process for the manufacture and preparation of
photographic paper, for. it is certain that at present all the paper
makers are working in the dark as far as principles are concerned.
Cansons, the French makers, are, I am told by Dr. Warren de la Rue,
noted for the insolubility of their paper-size, but unfortunately
for us they will not disclose their process, consequently there can
be no interchange of ideas between chemical photographers and
themselves.
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