IMPROVEMENTS IN TREATING AND BEAUTIFYING CHINA, PORCELAIN, AND EARTHENWARE OR POTTERY WARE, AND IN APPARATUS TO BE USED THEREFOR.
Year: 1879

page_text: LETTERS PATENT to William Langwell, of Attercliffe, Sheffield, in the County
of York, for the Invention of "IMPROVEMENTS IN TREATING AND BEAUTIFYING
CHINA, PORCELAIN, AND EARTHENWARE OR POTTERY WARE, AND IN APPARATUS
TO BE USED THEREFOR.'
"
Sealed the 18th May 1880, and dated the 20th November 1879.
PROVISIONAL SPECIFICATION left by the said William Langwell at the
Office of the Commissioners of Patents on the 20th November 1879.
WILLIAM LANGWELL, of Attercliffe, Sheffield, in the County of York. “IMPROVE-
MENTS IN TREATing and Beautifying China, PorCELAIN, AND EARTHENWARE OR
POTTERY-WARE, AND IN APPARATUS TO BE USED THEREFOR."
"
This Invention relates to the treatment of china, porcelain, and earthenware or
pottery-ware articles or goods, with the object of beautifying their surfaces by
producing iridescent colors or tints thereon, and thus greatly enhancing their
appearance and value.
To attain this result I subject the china or other ware, or the article or goods
usually made of such wares, such as ornamental slabs, tiles, bricks, knobs, or other
analogous articles, to the fumes of tin or other metallic salts when acted upon by
bydrochloric or other acids. The proportions of the salts which I prefer to use are
as follows:-100 parts of chloride of tin, 6 parts each of nitrate of strontium and
of nitrate of barium. These ingredients I thoroughly mix together and use in such
quantities as may be required to produce the desired effects. The above mentioned
proportions will yield very beautiful tints, but they may be varied in order to get
hues or tints of different intensities.
I subject the china or other ware to the said fumes while in its burning state or
when sufficiently burnt in the kiln, and on the heat being reduced to a dull red or
upon being reheated to such a degree.
As a very advantageous way of carrying my Invention into effect, I prefer to
carry out my improved process while the articles are supported in the saggers, in
the kiln or oven, after they have been sufficiently burnt and on the heat being
reduced to a dull red. The pile of saggers is made air-tight to prevent the fumes

page_text: escaping, the top one thereof is therefor covered in, and the bottom of each sagger
is perforated, or the saggers are otherwise provided or formed to allow of the free
access of the fumes throughout the pile or "bung," the mixture of metallic salts
being placed in the bottom sagger at the proper time, as above mentioned, through
a side aperture which is subsequently closed, the kiln or oven being likewise made
with a small opening opposite the aperture in the bottom sagger; the fumes then
rising up throughout the pile or "bung" of saggers speedily produce the desired
iridescence or tinting of the surface of the china or other ware.
I also accomplish the object of my Invention by reheating the china ware or
other goods, and then subjecting them to the said fumes. I effect this by making
a flue or tunnel, say of about 20 yards in length by 2 feet in height and 2 feet in
width, about centrally of the length of which I place a kiln or muffle which I keep
red-hot. I place the goods to be operated upon in iron pans, and insert them at the
cold end of the tunnel or flue and gradually draw them up to the fire, and when
red hot I cause each article to be subjected to the said fumes, and then pass it on in
the iron pan down the other side to gradually cool. Or the goods may be re-heated
in a kiln and taken separately and placed in a muffle and then subjected to the
said fumes, the salts being admitted thereto through a small opening in the bottom
thereof or placed into a small iron pan, the articles then being replaced in a kiln to
cool.
Or the goods may be re-heated in a muffle until they attain a dull red heat,
and then subjected therein to the said fumes, the application of which to
ornamental earthenware or pottery ware articles or goods is of great advantage,
as previously mentioned.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said William Langwell in the Great Seal Patent Office on the 20th May
1880.
WILLIAM LANGWELL, of Attercliffe, Sheffield, in the County of York.
"IMPROVE-
MENTS IN TREATING AND BEAUTIFYING CHINA, PORCELAIN, AND EARTHENWARE OR
POTTERY-WARE, AND IN APPARATUS TO BE USED THEREFOR.'
"
This Invention relates to the treatment of china, porcelain, and earthenware, or
pottery ware articles or goods, with the object of beautifying their surfaces by
producing iridescent colors or tints thereon, and thus greatly enhancing their
appearance and value.
To attain this result I subject the china or other ware or the articles or goods
usually made of such wares, such as ornamental slabs, tiles, bricks, knobs, or other
analogous articles, to the fumes of tin or other metallic salts when acted on by
hydrochloric or other acids. The proportions of the salts which I prefer to use
are as follows:-100 parts of chloride of tin, and 6 parts each of nitrate of
strontium and of nitrate of barium. These ingredients I thoroughly mix together
and use in such quantities as may be required to produce the desired effects.
The above mentioned proportions will yield very beautiful tints, but they may be
varied in order to get hues or tints of different intensities.
I subject the china or other ware to the said fumes while in its burning state
or when sufficiently burnt in the kiln, and on the heat being reduced to a dull
red or upon being re-heated to such a degree.
As a very advantageous way of carrying my Invention into effect, I prefer to
carry out my improved process while the articles are supported in the saggers in
the kiln or oven, after they have been sufficiently burnt, and on the heat being
reduced to a dull red. A pile of saggers or only one sagger may be used. The
bottom of each sagger is perforated, or the saggers are otherwise provided or
formed to allow of the free access of the fumes throughout the pile or "bung," the
mixture of inetallic salts being placed in the bottom sagger at the proper time, as
above mentioned, through a side aperture which is subsequently closed, the kiln or
oven being likewise made with a small opening opposite the aperture in the bottom
Bagger; the fumes then rising up throughout the pile or bung of saggers speedily
produce the desired iridescence or tinting of the surface of the china or other ware.
I also accomplish the object of my Invention by re-heating the chinaware or
other goods, and then subjecting them to the said fumes. I effect this by making
a flue or tunnel, say of about 20 yards in length by 2 feet in height and 24 feet
in width, about centrally of the length of which I place a kiln or muffle which I
keep red-hot. I place the goods to be operated upon in iron pans, and insert
them at the cold end of the tunnel or flue and gradually draw them up to the
fire, and when red hot I cause each article to be subjected to the said fumes,
and then pass it on in the iron pan down the other side to gradually cool Or the
goods may be re-heated in a kiln and taken separately and placed in a muffle, and
then subjected to the said fumes, the salts being admitted thereto through a small
opening in the bottom thereof or placed into a small iron pan, the articles then
being replaced in a kiln to cool. Or the goods may be re-heated in a muffe until
they attain a dull red heat, and be then subjected therein to the said fumes, the
application of which to ornamental earthenware or pottery ware articles or goods is
of great advantage, as previously mentioned.
Having now described the nature and object of my said Invention together with
the manner in which the same is to be or may be performed or carried into
practical effect, I would remark in conclusion that I claim as the Invention secured
to me by the hereinbefore in part recited Letters Patent,―
The novel and peculiar treatment of all kinds of china, porcelain, and earthen-

page_text: ware or pottery ware articles or goods by the methods and means substantially as
herein before described, with the object of beautifying the surfaces of such articles
or goods by producing iridescent colors or tints thereon, resulting in their value
and appearance being greatly enhanced.
In witness whereof, I, the said William Langwell, have hereunto set my hand
and seal, this Thirteenth day of May, in the year of our Lord One thousand
eight hundred and eighty.
W. LANGWELL. (L.S.)