Combining Prism Pavements and Reflectors in the Forward Part of the Vault to Light Basements.
Year: 1897

page_text: Date of Application, 13th July, 1397-Accepted, 18th Sept., 1897
COMPLETE SPECIFICATION.
Combining Prism Pavements and Reflectors in the Forward Part of
the Vault to Light Basements.
I, JOHN MEIGGS EWEN, of No. 1129 The Rookery, Chicago, County of Cook,
State of Illinois, United States of America, Mechanical Engineer, do hereby
declare the nature of my invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to devices for illuminating basements and has for its
object to provide means for directing the light received on a prism pavement at
the top of the vault in front of the basement back on approximately horizontal
lines into the basement.
The invention is illustrated in the accompanying drawings, wherein
Figure 1 is a cross-section of a basement with my improvement in position;
Figure 2 is a similar cross-section with the parts somewhat differently arranged;
Figure 3 shows the reflector consisting of a series of reflecting surfaces;
Figure 4 shows the reflector consisting of a glass plate provided with prisms,
the prisms being silvered or mirrored so as to reflect the light.
Like letters refer to like parts throughout the several figures.
A is the basement, B is the vault, C the prism tiles of the prismatic pavement D.
E is the reflector preferably hinged at F and provided with a suitable support
at G. The prism tiles are provided with prisms H having reflecting surfaces as
indicated, whereby the rays of light J entering the receiving surfaces of the prism
tiles are reflected by the reflecting surfaces of the prisms into the directions
indicated at K, are received upon the reflecting surface E and are thence dis-
charged in the directions indicated at L. In Figure 3 I have shown the reflector E
as broken up into a series of reflecting surfaces, and in Figure 4 I have shown a
reflector consisting of a piece of glass provided at its back with prisms, the surfaces
of the prisms being silvered or mirrored so as to reflect the light. When these
two forms are used, the reflector may be placed directly against the front wall of a
basement so as not to project out into the basement, the inclination of the reflect-
ing surface directing the light in the proper direction. When the device shown
in Figure 4 is used, the light is refracted by the glass in addition to being
reflected, the refraction aiding to change the direction of the light.
Having now particularly described and ascertained the nature of
my said
nvention, and in what manner the same is to be performed I declare that what I
claim is:-
An illuminating device for basements comprising a reflecting surface placed at
he forward end of the vault beneath the pavement in a nearly vertical position,
acing toward the basement, and a prism pavement having prism lights set so as
o receive the light from above and throw it toward the forward part of the vault
nd away from the basement, the prism light and the reflector being of such shape
nd so related to each other as that the light is taken from above, transmitted
[Price S1

page_text: through the pavement lights, thrown toward the front part of the vault beneath
the pavement and then reflected and thrown back into the basement, leaving the
principal part of the vault free from any reflector or prism plates or the like.
Dated this 13th day of July 1897
For the Applicant,
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.