Improvements in the Manufacture of Lamp Glasses for Safety Lamps, and such like Glasses for similar uses.
Year: 1893

page_text: Date of Application, 29th May, 1893
Complete Specification Left, 28th Feb., 1894-Accepted, 25th May, 1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Lamp Glasses for Safety
Lamps, and such like Glasses for similar uses.
A communication from abroad by AUGUST KATTENTIDT, of the Firm of
W. Limberg & Co., of Gifhorn, near Lüneberg, Hanover, in the German
Empire, Manufacturer.
I ALFRED GEORGE BROOKES of 55 and 56 Chancery Lane in the County of
London, Chartered Patent Agent do hereby declare the nature of this invention to
be as follows:-
This invention relates to the manufacture of lamp glasses or shades for safety
lamps and such like glasses for similar uses.
The object of the invention is the better production of such glasses with portions
thereof adapted to reflect or partially reflect the rays of light from a miner's safety
lamp or similar lamp or light.
In carrying out the invention the glass for instance a thick short cylinder
adapted to surround the flame in a safety lamp is for a portion of its surface-say
outside-covered with gold or other similar reflecting material and in the case of
gold this may be effected by the application of a solution of liquid bright gold
which is then burnt in to the glass and then a coating of enamel or like protective
covering is applied and similarly fixed thereupon.
The form of the gold application may be a solution of gold dissolved in
HNO, +4 HCl. or 1 part nitric and 4 parts hydrochloric acid and known as aqua
regia (königswasser) and diluted with a composition of several oils and essences
which evaporate along with the aqua regia during the process of burning in,
or treatment with beat in the furnace leaving the gold forming the reflecting
Burface.
The covering enamel may consist of a suitable white opaque glass such as is
known as alabaster glass with an intermediate application of lead in order to make
it fusible.
The gold will be replaced by other metal according to the effect required.
By these means a reflecting gold or other surface may be attained of great
durability and beauty and at a moderate cost of production whilst the coating may
be also translucent to a greater or less degree as may be desired.
Dated the 29th day of May 1893.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Lamp Glasses for Safety
Lamps, and such like Glasses for similar uses.
A communication from abroad by AUGUST KATTENTIDT, of the Firm of
W. Limberg & Co., of Gifhorn, near Lüneberg, Hanover, in the German
Empire, Manufacturer.
I ALFRED GEORGE BROOKES of 55 and 56 Chancery Lane, in the County of
London, Chartered Patent Agent 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:-
This invention relates to the manufacture of lamp glasses, or shades for safety
lamps and such like glasses for similar uses.

page_text: The object of the invention is the better production of such glasses with portions
thereof adapted to reflect or partially reflect the rays of light from a miner's safety
lamp, or similar lamp, or light.
In carrying out the invention the glass for instance a thick short cylinder
adapted to surround the flame in a safety lamp is for a portion of its surface-say
outside covered with gold, or other similar reflecting material and in the case of
gold this may be effected by the application of a solution of liquid bright gold
which is then burnt into the glass and then a coating of enamel or like protective
covering is applied and similarly fixed thereupon.
The form of the gold application may be a solution of gold in a solvent such as
is known as aqua regia (königswasser). The substances added after dissolving the
gold in aqua regia are two parts of a mixture of turpentine oil and Venetian
turpentine, preferably in the proportion of five parts of turpentine oil to one part
of Venetian turpentine, and one part lavender oil to which is added for a flux
small quantities of tin, antimony and bismuth. These oils and essences evaporate
along with the aqua regia during the process of burning in or treatment with heat
in the furnace leaving the gold forming the reflecting surface.
The covering enamel may consist of a suitable white opaque glass such as is
known as alabaster glass with an intermediate application of lead in order to make
it fusible.
The gold will be replaced by other metal according to the effect required.
According to another modification the gold, silver or other metallic reflecting
surface is burned into the inner surface of the glass cylinder, or shade and the
backing, or covering enamel is applied on the outer surface.
In preparing a silver reflector: say, a glass cylinder-for a miner's safety lamp,
I employ a layer of silver in the form of a solution of bright silver put on in a cold
state and then melted into the glass in the furnace so that it is unchangeable and
can only be separated from the glass by grinding off a layer (top layer) of the
glass. It is therefore not a simple process of burning in but one of melting in.
On the back of the glass is applied a suitable black enamel. A suitable solution
or preparation of silver nitrate Ag.NO, is treated with the same composition as
above described with regard to gold.
The enamel may be of suitable usual kind such as is employed for melting on
glass bottles and the like for labelling and the like.
By these means a reflecting silver, gold or other surface may be attained of
great durability and beauty and at a moderate cost of production whilst the coating
may be also translucent to a greater or less degree as may be desired.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
The manufacture of reflecting surfaces of metal or the like upon glasses for
miners' safety lamps and such like glasses, as set forth.
Dated the 28th day of February 1894.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.