Improved Testing Device for Selecting Prisms for Windows and the like.
Year: 1897

page_text: Date of Application, 4th May, 1897-Accepted, 21st Aug., 1897
COMPLETE SPECIFICATION.
Improved Testing Device for Selecting Prisms for Windows and
the like.
I, OLIN HANSON BASQUIN, of No. 1410 Marquette Building, Chicago, County of
Cook, State of Illinois, United States of America, Gentleman, do hereby declare the
nature of my 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 testing devices to be used in connection with prismatic
lights and has for its object to provide a testing device by which any given
window can be provided with prismatic glass and for indicating the dimensions
of the prisms to be used in any given window in order to best direct the light toward
any given point.
My invention is illustrated in the accompanying drawings, wherein
Figure 1 is a view of a set of testing prisms in position in the testing frame;
Figure 2 is a view of the testing prisins separated from the testing frame;
Figure 3 is a view of a modified form of testing frame and prisms;
Figure 4 is a view of a further modified form of testing frame;
Figure 5 is a section on line 5-5, Figure 4;
Like letters refer to like parts throughout the several figures.
Referring to the accompanying drawings, I have shown in Figure 1 a series of
tiles or plates A of prismatic glass bound together in any suitable manner as for
example, by means of the frame B. These tiles or plates A are provided withr prisins
of varying angles. The prisms on any given tile may be of the same angle, the
angles of the prisms on the various tiles being different or each tile may be made
up of a set of prisons of various angles. The frame B is adapted to be connected
to the testing frame C and may be stationary with relation to the testing frame when
in position or the two frames may have a relative movement so that one set of
prisms can be replaced by another. The prisms may be used separate from the frame
if desired. In Figure 3 I have shown the testing frame as consisting of a skeleton
frame having the sides D and E connected together by the rods or pieces F and
provided with a handle F1 by which it is supported. In this construction, a set of
prisms is used, the prisms being placed end to end and connected together so as to
be held in place by the guides D. The sides D and E may be entirely open or may
simply be provided with one or more small holes. As shown in Figures 4 and 5,
the testing frame C consists of a closed box having the two openings C₁ and C².
The prisms C are made with varying angles and are placed in the frame B.
These prisms are preferably placed so that the angles gradually vary from one end
toward the other. This frame is held in place by means of the guides D¹, and the set
of prisins is adapted to be slid along said guides so as to be moved in position
opposite the openings C' and C. The testing frame may also be provided with the
handle F by which it can be supported in the proper position. The prisms in
connection with my device may be supported in any desired manner and each prism
may have its dimensions marked upon it so that the dimension of the prism to be
used can be easily and quickly ascertained by inspection. I have shown several
forms of testing devices embodying my invention, but it is of course evident that the

page_text: form, construction and arrangement may be varied without departing from the spirit
of my invention and I therefore do not wish to be limited in any particular to the
construction herein shown and described.
The use and operation of my invention are as follows:-
When prismatic lights are used, as for example, in windows or the like, it is found
that the result obtained from a given window at any given point depends upon the
shape of the prisms used, that is, upon the angles of the surfaces of the prisms.
When it is desired to find what prismns should be placed in a given window in order
to throw the light in a given direction, the testing frame is placed so that the light
from the window falls upon the prisms, the frame being so positioned that the given
direction in which the light is to be thrown is that from the prisms to the observer's
eye. It will be found that some of the prisms look bright and the others dark,
the dark prisms being found at one end and the bright prisins at the other. The
point where the prisms change from dark to light is noted, the first bright prisin
representing the prismn to be used in the window. The angle of this first bright
prism is noted and hence the angles of the prisms to be used will then be known,
When the device shown in Figures 1 and 2 is used the prisms may be used in
connection with the testing frame or they may be placed at the window, the
observer standing back at the point where the light is to be directed and picking
out the proper prism.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:
A testing device to be used in connection with Prismatic Lights constructed
hotantially as bomain cot forth
borain cot forth
Deted this 4th day of May 1907
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.
his 4th day of May
1807
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.
F. WISE HOWORTH,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.