Improvements in the Manufacture of Articles of Pressed Glass.
Year: 1889

page_text: Date of Application, 14th Feb., 1889
Complete Specification Left, 6th Nov., 1889-Accepted, 7th Dec., 1889
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Articles of Pressed Glass.
I, THOMAS DAVIDSON, of Teams Flint Glass Works, Gateshead-on-Tyne, in the
County of Durham, Glass Manufacturer, do hereby declare the nature of this invention
to be as follows:-
According to my invention I manufacture articles such for example as ornamental
dishes, vases, jugs, tumblers, and the like of pressed glass in such a manner that
at the base they are composed of clear glass or glass of any transparent color
whilst towards the top they gradually become milky and at their upper edge
opaque.
This I effect in the following manner :-
I take phosphate of lime, arsenic and limespar, and mix them well with the
ordinary materials used for making flint glass, and expose the mixture thus obtained
in the usual way in a crucible until ready for working.
The glass is then moulded in the usual way for making pressed glass.
The moulded article which at this stage is transparent I allow to cool for a short
time and then expose it on a punty or rod in a strong heat, it then assumes the
effect described; the parts most heated being most opaque, and the parts not heated
so much remaining clear which is regulated by the workmen according to the length
of time the article is kept in the flame.
I find the following batch suitable but I do not confine myself to any particular
batch :-
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Articles of Pressed Glass.
I, THOMAS DAVIDSON, of Teams Flint Glass Works, Gateshead-on-Tyne, in the
County of Durham, Glass Manufacturer, do hereby declare the nature of this
Invention and in what manner the same is to be performed to be particularly described
and ascertained in and by the following statement :-
According to my invention I manufacture articles such for example as ornamental
dishes, vases, jugs, tumblers, and the like of pressed glass in such a manner that
at the base they are composed of clear glass or glass of any transparent color
whilst towards the top they gradually become milky and at their upper edge
opaque.

page_text: Inis I erect in the following manner :-
I take phosphate of lime, arsenic and limespar, and mix them well with the ordinary
materials used for making flint glass, and expose the mixture thus obtained in the
usual way in a crucible until ready for working.
The glass is then moulded in the usual way for making pressed glass.
The moulded article which at this stage is transparent I allow to cool for a short
time and then expose it on a punty or rod in a strong heat, it then assumes the effect
described; the parts most heated being most opaque, and the parts not heated so much
remaining clear which is regulated by the workinen according to the length of time
the article is kept in the flame.
I find the following batch suitable but I do not confine myself to any particular
batch.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The manufacture of pressed glass, by adding phosphate of lime, lime spar and
arsenic to the ordinary materials, moulding the article in the usual manner from the
mixture, allowing the article to cool slightly and then reheating it in such manner
that it becomes' hotter in some places than in others.
2. The manufacture of pressed glass by adding phosphate of lime, lime spar and
arsenic to the ordinary materials in about the proportions specified, moulding the
article in the usual manner from the mixture, allowing the article to cool slightly and
then reheating it in such manner that it becomes hotter in some places than in
others.
Dated this 21st day of October 1880.
THOS. DAVIDSON.