Improvements in Globes for Arc Lights, or other Lights of Great Intensity.
Year: 1895

page_text: Date of Application, 20th June, 1895
Complete Specification Left, 19th Mar., 1896-Accepted, 20th June, 1896
PROVISIONAL SPECIFICATION.
Improvements in Globes for Arc Lights, or other Lights of Great
Intensity.
I, WILLIAM JANDUS, of The Jandus Arc Lamp and Electric Company
Limited, Victoria Works, Old Charlton, in the County of Kent, Electrical
Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to an improvement in globes for surrounding arc lights,
and other lights of an intense nature, and its object is to secure the dispersal of
the light in such manner as to avoid annoyance to the eyes, while preventing the
loss of light at present caused by the use of opalescent or ground globes for this
purpose.
When opalescent or ground globes are used to surround such lights, the arc
itself or other centre of light, is made invisible to the eye, and the whole globe
appears to be uniformly illuminated, thus giving an agreeable effect, but a very
great loss of light is incurred, often as much as 30% of the total light.
My invention consists in the construction of two or more globes in a peculiar
manner, so as to diffuse the light and prevent the arc from being seen directly,
while at the same time avoiding the loss of light which at present occurs.
In one method of carrying my invention into effect I construct an inner globe
or chamber to surround the arc light which globe or chamber I form preferably
with horizontal grooves all round it, the said horizontal grooves being arranged
so as to form a number of prismatic ribs. I surround this inner vessel, globe or
chamber with an outer globe or chamber, on which globe or chamber I form a
series of preferably vertical grooves, passing vertically round the globe or
chamber.
When the grooves are formed vertically on the outer globe the rain serves to
wash all dust out of the grooves.
Although both globes or chambers are formed of clear glass without grinding
or opalescence, the effect of the oppositely disposed ribs is to illuminate the whole
glass of the outer globe, and cause it to diffuse light uniformly without showing
undue intensity at any one point. More than two globes or chambers may be so
arranged if desired, the object of the invention being by means of oppositely
disposed ridges or grooves, or prismatic ridges, to so diffuse the light from the are
as to equally illuminate the outer globe to minimise shadows, and prevent any
annoying effect on the eyes, without undue loss of light by absorption."
Dated this 20th don of June 1805
MARKS & CLERK,
18 Southampton Buildings, London, W.C., and
13 Temple Street, Birmingham, Agents for Applicant.

page_text: Improvements in Globes for Arc Lights, or other Lights of Great.
Intensity.
I, WILLIAM JANDUS, of The Jandus Arc Lamp and Electric Company
Limited, of Victoria Works, Old Charlton, in the County of Kent, Electrical
Engineer, 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 :-
My invention relates to an improvement in globes for surrounding arc lights,
and other lights of an intense nature, and its object is to secure the dispersal of
the light in such manner as to avoid annoyance to the eyes, while preventing the
loss of light, at present caused by the use of opalescent or ground globes for this
purpose.
When opalescent or ground globes are used to surround such lights, the arc
itself or other centre of light, is made invisible to the eye, and the whole globe
appears to be uniformly illuminated, thus giving an agreeable effect, but a very
great loss of light is incurred, often as much as 30 per cent. of the total light.
My invention consists in the construction of two or more globes in a peculiar
manner, so as to diffuse the light and prevent the arc from being seen directly
while at the same time avoiding the loss of light which at present occurs.
Referring to the accompanying sheet of drawings-
Figure 1 is a vertical section through outer and inner globes constructed in
accordance with my invention.
Figure 2 is an external elevation of the outer globe showing the vertically
disposed grooves.
Figure 3 is an external elevation of the inner globe showing the horizontal
grooves.
Figures 4, 5, 6, and 7 are sections on a larger scale showing a few of the forms
of grooves which may be used.
In one method of carrying my invention into effect I construct an inner globe
or chamber as B to surround the arc light which globe or chamber I form
preferably with horizontal grooves as B' all round it, the said horizontal grooves
being arranged so as to form a number of prismatic ribs. I surround this inner
vessel, globe or chamber with an outer globe or chamber as A on which globe or
chamber I form a series of preferably vertical grooves as A' passing vertically
. round the globe or chamber.
When the grooves are formed vertically on the outer globe the rain serves to
wash all dust out of the grooves.
Although both globes or chambers are formed of clear glass without grinding
or opalescence, the effect of the oppositely disposed ribs is to illuminate the whole
glass of the outer globe, and cause it to diffuse light uniformly without showing
undue intensity at any one point. More than two globes or chambers may be so
arranged if desired, the object of the invention being by means of oppositely
disposed ridges or grooves, or prismatic ridges, to so diffuse the light from the are
as to equally illuminate the outer globe to minimise shadows, and prevent any
annoying effect on the eyes, without undue loss of light.by absorption.
Various suitable forms of ridges or grooves A³ are shown at Figures 4, 5, 6,
and 7 as applied to the outside globe A but the same or similar grooves may be
applied to the inner globe.
Although I prefer to make my opposing grooves, horizontal and vertical, yet
I may make them diagonal that is, oppositely diagonal on the inner and outer
globes with much the same result as to diffusion of light.

page_text: The parts C shown in section in Figure 1 are the arms which hold the lower
carbon and inner globe.
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 ;-
Forming outer and inner globes for arc lamps and other lamps of great intensity
with grooves traversing the globes in such directions that the lines are opposed
in direction that is the planes through the outer lines intersect the planes through
the inner globe lines substantially as and for the purposes described.
Darcu HIS LOVE
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.