Improvements in Globes for Lamps.
Year: 1895

page_text: Date of Application, 31st Dec., 1895-Accepted, 1st Feb., 1896
COMPLETE SPECIFICATION.
Improvements in Globes for Lamps.
I, GEORGE CROYDON MARKS, of 18 Southampton Buildings, Chancery Lane,.
London W.C., Patent Agent and Consulting Engineer, (a communication from
abroad by Charles Freeman Brown, of Reading, Massachusetts, United States of
America, Gentleman), 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 :-
The invention consists in a glass globe or shade formed to surround a source of
light, such as a gas-flame or an incandescent filament, and having a series of prisms.
which form angular ribs on the inner surface of the globe or shade, the said prisms
being arranged so that each bears throughout its entire length the same relation to
the enclosed source of light that all the others bear, the light being therefore-
reflected and affected alike by all the prisms.
Of the accompanying drawings, forming a part of this Specification,―
Figure 1 represents a side elevation of an incandescent-lamp globe or shade.
embodying my invention.
Figure 2 represents an end view of the same.
Figure 3 represents a section on line 3-3, Figure 1.
Figure 4 represents a perspective sectional view of a globe or shade open at both.
ends and adapted for use in connection with gas burners.
Figure 5 represents a section on line 5-5, Figure 4.
The same letters of reference indicate the same parts in all the figures.
In carrying out my invention, I provide the interior of a hollow glass globe or
shade with prism-shaped ribs a, relatively arranged like the meridian lines on a
terrestrial globe, and presenting acute angles on the interior of the globe or shade.
The width of each prism is greater at the middle part of its length than at its
ends. The external surface of the shade is smooth and has no projections or
angles.
By the described meridian-line arrangement of prisms on the interior of an.
externally smooth hollow glass globe or shade, I cause all the prisms to bear a
uniform relation to the enclosed light, so that the light is diffused and reflected
uniformly throughout all parts of the space into which the rays of light pass.
through the shade.
In Figures 1, 2, and 3, I show a globe or shade adapted to enclose an incan-.
descent electric-lamp filament and having a single opening a³. Some of the prisms
are longer than others and converge to a common centre a² opposite said opening..
The shorter prisms terminate at a distance from said centre, their ends being
designated at. By this arrangement. I am enabled to give the prisms a sufficient
operative depth around the point a² and avoid crowding them to such an extent as.
to impair their effect.
In Figures 4 and 5, I show the prisms as arranged on a gas globe or shade, the
principal difference being that the shade has two openings, as usual, instead of one
as in the form shown in Figures 1, 2, and 3.
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. A hollow glass globe or shade having on its inner surface prisms relatively.
avenged like manidine anhatansallast forth

page_text: 2. A hollow glass globe or shade having a single opening, and alternating
longer and shorter prisms on its inner surface, relatively arranged like meridians,
the longer prisms converging to a point opposite said opening.
Dated this 31st day of December 1895.
MARKS & CLERK,
18, Southampton Buildings, London, W.C., and
13, Temple Street, Birmingham, Agents.