IMPROVEMENTS IN THE MANUFACTURE OF GLASS OF A NOVEL COLOUR
Year: 1878

page_text: LETTERS PATENT to John George Sowerby, of Ellison Flint Glass Works,
Gateshead, in the County of Durham, Glass Manufacturer, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF GLASS OF A NOVEL COLOUR."
Sealed the 18th October 1878, and dated the 29th May 1878.
PROVISIONAL SPECIFICATION left by the said John George Sowerby at
the Office of the Commissioners of Patents on the 29th May 1878.
JOHN GEORGE SOWERBY, of Ellison Flint Glass Works, Gateshead, in the County
of Durham, Glass Manufacturer. "IMPROVEMENTS IN THE MANUFACTURE OF GLASS
OF A NOVEL COLOUR."
My Invention relates to the production of a description of glass of a peculiar
yellowish colour or body, termed ivory.
An approximation to this colour or body has been obtained by adding to the
usual ingredients of common flint glass, arsenic to make the glass opaque; and
uranium, to give it the yellow tint.
I obtain a much finer body than can be obtained by the above combination, in
fact, a china body, by dispensing with the arsenic and substituting cryolite.
I am aware that cryolite is largely used in glass making, but not in conjunction
with uranium or for the object of my Invention.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John George Sowerby in the Great Seal Patent Office on the 28th
November 1878.
JOHN GEORGE SOWERBY, of Ellison Flint Glass Works, Gateshead, in the County
of Durham, Glass Manufacturer. "IMPROVEMENTS IN THE MANUFACTURE OF GLASS
OF A NOVEL COLOUR."
My Invention relates to the production of a description of glass of a peculiar
yellowish colour or body, termed "ivory."
An approximation to this colour or body has been obtained by adding to the
usual ingredients of common flint glass, arsenic to make the glass opaque; and
uranium, to give it the yellow tint.
I obtain a much finer body than can be obtained by the above combination, in
fact, a china body, by dispensing with the arsenic and substituting cryolite spar.
My combination of cryolite and uranium may be added to any ordinary batch
for flint glass, and I find a batch composed as follows answer very well
.
Sand
cwt.qrs. lbs.
12 0 0
58%
Soda
Baryta (Carb.)
Nitrate of Soda
-
1
0 0
-
1
1
0
-
1
1 0
Manganese
0 0 14
To every 12 cwt. of this batch I add 24 lbs. of uranium, and 1 cwt. 3 quarters
8 lbs. of cryolite, and operate as in making ordinary flint glass.
I am aware that cryolite is largely used in glass making, but not in conjunction
with uranium or for the object of my Invention.
Having now described and ascertained the nature of my said Invention, and in
what manner the same is or may be performed, I desire it to be understood that I
do not restrict myself to the proportions above given, nor to any particular relative
proportion of the cryolite to the uranium, or to any other of the ingredients above
enumerated, or which may be used in the manufacture of glass, as such may be
varied according to the quality of the ingredients used and otherwise, and that what
I claim as secured to me by the herein-before in part recited Letters Patent is, the use
in the manufacture of glass, of cryolite in combination with uranium, and the usual
ingredients of glass making, substantially as and for the purpose above specified.
In witness whereof, I, the said John George Sowerby, have hereunto set
my hand and seal, this Nineteenth day of November, in the year of our
Lord One thousand eight hundred and seventy-eight.
JOHN GEORGE SOWERBY. (L.S.)