Year: 1885

page_text: We, LOUIS JOHN CROSSLEY of Dean Clough Mills, Halifax in the County of
York, Carpet Manufacturer and JAMES JOSEPH HICKS of 8 Hatton Garden in the
County of Middlesex, Meteorological Instrument Manufacturer, do hereby declare
the nature of the said Invention to be as follows:-
Heretofore the bulbs or glasses of incandescent electric lamps have been made of
glass which has been wholly clear or translucent or they have been made of entirely
semi-transparent or colored glass..
L
They, have also been made of clear glass but in order to enable them to reflect
the light, one side of the bulb has been silvered which is an expensive process and
at the same time produces an intensely dazzling reflection.
Now according to our invention we form the said bulbs partly of clear glass and
partly of white or colored enamel, the said enamel serving sufficiently to reflect the
light and yet avoid the dazzling effect produced by the silvering.
In carrying our invention into effect we first produce a tube which is mainly of
clear glass but which has embedded therein on one side a strip of enamel of sufficient
width to produce the desired reflecting surface.
We blow this tube into the form of bulbs and in doing so the enamel becomes
extended.around the centre of the bulb and gradually diminishes in width towards
the top and bottom thereof, so as to produce an efficient reflecting surface of the
desired extent and shape.
.

page_text: We LOUIS JOHN CROSSLEY of Dean Clough Mills, Halifax in the County of
York, Carpet Manufacturer and JAMES JOSEPH HICKS of 8 Hatton Garden in the
County of Middlesex, Meteorological Instrument 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 :-
Heretofore the bulbs or glasses of incandescent electric lamps have been made of
glass which has been wholly clear or translucent, or they have been made of entirely
semi-transparent or colored glass.
They have also, in order to enable them to reflect the light, been made of clear
glass and have had one side or part of the bulb silvered which is an expensive
process and at the same time produces an intensely dazzling reflection.
Now according to our invention in order to produce a reflecting lamp, we form
the said bulbs partly of clear glass and partly of white enamel.
In carrying our invention into effect, we first produce a tube such as that
represented in cross section at Figure 1.
This tube is made mainly of clear or translucent glass but has embedded between
two thicknesses of the same a strip a of white enamel or glass extending the entire
length of the tube and of sufficient width to produce the desired extent of reflecting
surface in the finished glass or bulb.
We blow a sufficient length of this tube into the form required for the bulb or
glass b as shown at Figure 2, we then draw or cut off the bulb from the tube or
cane leaving a sufficient length of the tube attached for the formation of the neck
or bottom of the lamp, after which, we seal the wires c in the neck of such bulb
or glass b and exhaust and seal the latter in the way now well understood.
A bulb or glass made in the manner above described will have the enamel a
extended around the centre thereof to about half its circumference as shown at
Figure 3 but it may extend a less or greater distance as may be required.
By these means we produce an efficient reflecting surface of the desired extent
and shape.
For the purpose of producing a reflecting bulb or glass as above described we do
not use the ordinary weak enamel employed in the manufacture of thermometer
and barometer tubing, as in the operation of blowing the bulb or glass, such weak
enamel would lose its density and color to such an extent that it would consequently
become in-effective for the purpose intended.
We therefore use a denser and stronger enamel which contains a larger pro-
portion of arsenic, which when a piece of tubing containing the same has been
extended by blowing into the form of a bulb will retain sufficient density and
color to constitute an efficient reflector,

page_text: Having now particularly described the nature of our said invention, and in
what manner the same is to be perforined we declare that what we claim is :—
A bulb or glass for an incandescent electric lamp, blown from a length of tube
in which a width or strip of white enamel or glass is embedded substantially as
herein shown and described and for the purpose stated.
A
1000