IMPROVEMENTS IN TANNING HIDES AND. SKINS."
Year: 1880

page_text: LETTERS PATENT to Stephen Fitchew Cox, of Yatton, in the County of
Somerset, for an Invention of "IMPROVEMENTS IN TANNING HIDES AND.
SKINS."
PROVISIONAL SPECIFICATION left by the said Stephen Fitchew Cox at the
Office of the Commissioners of Patents on the 9th July,1880.
STEPHEN FITCHEW Cox, of Yatton, in the County of Somerset. "IMPROVEMENTS
IN TANNING HIDES AND SKINS."
This Invention has for its object improvements in tanning hides and skins.
In this process I make a judicious use of zinc or like metal as spelter, or other metals
(if any) possessing approximate properties reduced to particles, pulverized and in
the powdered state, or in solution. I apply it to the tanning ingredients, or to the
tan liquor, before or whilst the hides and skins are submerged with the ingredients,
or in the tan liquor, for converting the same into leather.
I proceed as follows:-
The hides and skins being depiled, fleshed, and prepared in the usual way in the
beam yard and made ready for the tanning process, are immersed for a few days in
weak or nearly spent tan liquor. In the meantime I prepare a pit or vat of tan
liquor made or obtained in the usual way from bark, valonia, or other tanning
ingredients, and of a strength according to the weight or description of the hides or
skins to be tanned. I apply to this liquor zinc or spelter in the particle or powdered
state, and I find in practice this is best applied together with ground bark, valonia,
or other tanning ingredients. In the case of putting the zinc powder and ingredients
together into the pit of liquor, it is desirable to suspend the hides and skins in the
pit, so that the tan liquor, tanning ingredients, together with the zinc, may have
an uniform action upon the whole of the pelt to be tanned; but in the alternative,
where the hides or skins are laid flat in the pits of tan liquor, then the tanning
ingredients and zinc particles should be well mixed and proportionally distributed
between the hides and skins as they are laid one by one in the pit of liquor. The
zine however may be applied to the liquor without the ground or dry ingredients
before described,
I find that the action of the zinc and ingredients (when immersed) or tan liquor
commences almost immediately, and continues for about 10 or 14 days, by which time
the stoutest hide is fully imbued with its effect as well as extensively tanned,
thickened, and made a beautiful color, and that the action of the zinc during this
time is quite sufficient to prepare the pelt to be fully tanned, bloomed, and filled by
the usual means, but in about one third of the time required in the ordinary process,
and will produce a brighter colored, thicker, and heavier leather than can be
obtained in the time by any other method.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Stephen Fitchew Cox in the Great Seal Patent Office on the 7th
January 1881.
STEPHEN FITCHEW Cox, of Yatton, in the County of Somerset.
IN TANNING HIDES AND SKINS."
"IMPROVEMENTS
This Invention has for its object improvements in tanning hides and skins.
In this process I make a judicious uso of zinc, spelter, or like metal, in powder,
or in a finely state.
I-prefer to proceed as follows:-The bides or skins are prepared in the beam
yard in the usual way, they are then steeped or washed in a weak or nearly spent
tan liquor. A now tan liquor also is provided: For heavy hides the strength of this
liquor should be about 40 degrees of the ordinary barkometer. This liquor I
prepare from bark and valonia, or other tanning ingredients, in the usual way. Also
for say sixty heavy hides or butts I prepare one hundredweight of ground bark, one
hundredweight of ground valonia, and two pounds of finely powdered zinc or
spelter. I mix, these dry materials well together. The hides are then laid flat in
the pit of liquor one by one, and in forming the heap the powdered materials are
distributed equally between the hides throughout the pile. Very shortly after the
wholo are in, a circulation will appear to be set up in the liquor by the action of
the powdered zinc or spelter. At the end of seven to fourteen days, during all which
time-the-circulation will appear to continue, the stoutest hides will have become
fully imbued with the effect, extensively tanned, thickened, and made of a beautiful
color.
:
Afterwards the hides or butts are taken out of this preparation, and-then fully
tanned, bloomed, and filled in the usual way, except that the operations may be
finished in one third of the time which would have been requisite if the hides had
not been prepared in the manner described. The leather obtained will be brighter
colored, thicker, and heavier than can be obtained in the same time by any other
method.
For lighter goods the process is conducted in a similer manner but with a some-
what weaker liquor, and with smallor quantities of the other ingredients.
I find in practice that a pit or vat of tan liquor and ingredients may be used
several times in serios, for a succession of batches of fresh hides to be prepared or
partly prepared.
Having thus described the nature of my said Invention, and the manner of
performing the same, I would have it understood that I do not confine myself to
the details of the process herein described, for the same may be varied, although I
have described the best process for working with which I am acquainted, but what
I claim is, the use in tanning of powdered zinc, spelter, or like metal, together with
tan liquor and tanning ingredients to operate on hides or skins immersed in such
liquor, substantially as herein described.
In witness whereof, I, the said Stephen Fitchew Cox, have hereunto set my
hand and seal, this Fourth day of January, in the year of our Lord
One thousand eight hundred and eighty one.