Apparatus for Producing Optical Illusions by Means of Mirrors.
Year: 1889

page_text: COMPLETE SPECIFICATION.
Apparatus for Producing Optical Illusions by Means of Mirrors.
We, JACOB KELLER, Merchant, of 10 Perlenpfuhl, Cologne, and GUSTAV CASTAN,
Sculptor, of 13 Stühlerstrasse, Berlin, both in the German Empire, 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 :-
Our invention chiefly relates to new combinations and arrangements of mirrors
which gives the visitor the impression that he is placed in a labyrinth formed by
colonnades or arcades, mirrors and painted views.
Although the apparatus occupies a very small space, the visitor believes to stand
before endless colonnades, and, if tempted to enter the same, he finds himself suddenly
stopped by a mirror, from which the deep colonnades seem to extend to the right and
to the left.
In the following description, reference will be made to the accompanying drawings,
which is a horizontal section of an apparatus embodying our invention.
In a building or room, preferably rectangular in section, are mounted a number of
mirrors S, so as to form the walls and partitions of a labyrinth, and two images or
pictures B, B. As indicated by the dotted lines, the individual compartments of
the labyrinth are composed of equilateral triangles, and all individual mirrors have
therefore the same width. Moreover, the heights and the frames of all the mirrors
are exactly alike, and the passages are enclosed by the same kind of frames. The
mirrors reflect into the interior of the individual compartments, the rays emanating
from the frames or borders, and, of course, also those from the visitors placed in the
same compartment or in several adjoining compartments, thus producing an immense
number of images of the frames and other objects in different positions.
Now, as all frames or borders, (those of the passages, as well as those of the
mirrors) are exactly alike in shape and size, and produce innumerable images by
reflection, persons not initiated will have much difficulty in finding the shortest
way from the entrance E to the kaleidoscope K (hereinafter described) or to the
exit A.
The pictures B, B1 printed or drawn on a wall or partition apparently form the
ends of the immense colonnades. Owing to the reflection by the mirrors, the
image B¹ becomes visible immediately on entering the labyrinth. At the point a
the visitor sees the persons who enter, and believes that they approach him through
a long hall. The rhombic compartment L contains an imitation of the Lion Court of
the Alhambra. In consequence of the position of the mirrors that form the walls
of the compartment, and of the columns applied on the same, the forest of columns
which in reality occupies a large space, is artificially reproduced on a surface having
scarcely 1 of the size of the original.
The hexagonal compartment P represents a tropical garden, and the background H
forms the entrance of a Moorish Temple, while palms and exotic plants are placed
between the mirrors. Owing to the multiple reflection, the single entrance appears
like an entire mosque, surrounded by a tropical garden. The space in which the
visitor stands, occupies scarcely 2 square meters, but the whole looks like a great palm
garden in a tropical country.
Our invention also comprises a specially constructed camera or kaleidoscope K
which has the shape of a regular tetrahedron. The three upper sides of the
tetrahedron are formed by three large triangular mirrors, the edges of which are
ground, and fitted together, so that the whole appears to be made of one piece.
The chamber K is entered from below through a circular staircase w, and a second
staircase to serves for the exit.

page_text: The visitor ascending the spiral staircase w sees a great number of repetitions
of his own image, from the front, from the back, and from both sides. Four or five
persons standing together in the kaleidoscope, appear as an innumerable crowd.
The entrance E of the labyrinth may have on the right side a cashier's room Cand
on the left side a cloak room G.
The apparatus, as shown by the drawing, may, of course, he modified to suit
various requirements, without departing from the principle of our invention. The
following are considered the essential features of novelty :-
(1). That the mirrors and passages are inclined to each other at an angle of 60° or
at a multiple of 60°, the horizontal section of the individual compartments being
composed of equilateral triangles.
(2). That the mirrors and passages are all alike as regards their width and height,
as well as the shape, size and design or decoration of the frames or borders.
(3). The kaleidoscope K, which is accessible only from below, while the sides or
walls are composed of large triangular mirrors, which form three adjoining sides of a
regular tetrahedron, and are therefore placed to each other and to the floor at an
angle of 60°.
Having now particularly described and ascertained the nature of our said Inven-
tion and in what manner the same is to he performed, we declare that what we
claim is :-
1. An optical illusion apparatus, composed of mirrors S and passages forming the
sides and partitions of a labyrinth or zig-zag course, the individual mirrors and passages
corresponding with each other exactly as regards their width and height, and as
regards the shape, size and decoration of their frames or borders, while the horizontal
section of the labyrinth or zig-zag course is composed of equilateral triangles which
determine the angle between adjoining mirrors and between the mirrors and passages;
substantially as described.
2. An optical illusion apparatus constructed as specified in claim 1, and provided
with images B, B₁; substantially as described.
3. An optical illusion apparatus, constructed as specified in claim 1, and provided
with a background H; substantially as described.
4. An optical illusion apparatus, constructed and adapted to operate substantially as
described and shown by the drawing, with or without a kaleidoscope.
5. A kaleidoscope K, accessible from below and composed of equilateral triangles
forming a regular tetrahedron, the sides of which are mirrors accurately fitted
together; substantially as described and illustrated.
Dated this 21st day of October 1889.
JACOB KELLER.
GUSTAV CASTAN.
By Fairfax & Wetter,
443, Strand, London, Agents.