AN IMPROVED MODE OF AND APPARATUS FOR PRODUCING SPECTRAL ILLUSIONS ON THE STAGE
Year: 1863

page_text: PROVISIONAL SPECIFICATION left by Horatio Nelson King at the
Office of the Commissioners of Patents, with his Petition, on the 18th
July 1868.
I, HOBATIO NELSON KING, of No. 42° Milsom Street, in the City of Bath,
Photographic Artist, do hereby declare the nature of the said Invention
for "AN IMPROVED MODE OF AND APPARATUS FOR PRODUCING SPECTRAL ILLUSIONS
ON THE STAGE," to be as follows:-
I make an opening in the stage about eight feet behind the foot lights or
front of the stage, the depth of the opening from front to back being about six
feet, and occupying so much of the width of the stage as may be necessary to
exhibit the objects intended to be represented. I place a piece of plate glass
with its lower edge resting upon the hinder edge of the opening, and inclining.
forward at an angle of 45 degrees. The piece of plate glass should reach
sufficiently high to shew the objects intended to be represented, and its edges..
should be concealed by scenery or in some other convenient mode, having.
regard to the objects to be exhibited. I construct a floor about eight feet
below the stage, and I place a mirror, the lower edge of which rests upon the
floor and the upper edge against the front edge of the opening in the stage;
the mirror is to be parallel to the piece of plate glass. The width of the
mirror will depend upon the objects to be exhibited, and if it is less than the
width of the plate glass it must be capable of being moved laterally if the
spectral figure on the stage is to have any lateral motion. A person dressed
to represent the spectral figure it is intended to produce on the stage is placed

page_text: on the floor underneath and behind the mirror, so that his image will be
reflected by the mirror upwards through the opening in the stage upon the
plate glass; it will then be reflected by the surface of the plate glass to the
spectators, and will appear to them to be standing on the stage the same
distance behind the plate glass as the person on the floor underneath the stage
is distant from the mirror. When the person approaches the mirror his
reflected image, which forms the spectral illusion, will appear to approach the
front of the stage, and as the person retires the spectral illusion will appear to
recede. All objects and persons actually on the stage will be perfectly visible
to the spectators through the plate glass, and the spectral figure will appear to
Le amongst them. It will be necessary to illumine the person under the
stage with a very strong light, and for that purpose the light of the lime or
electric light or any other sufficiently strong light must be concentrated upon
him by any suitable apparatus placed under the stage, and as much in front of
him as the position of the mirror will allow. I find that the best effect is
produced by concentrating the light of the line or electric light upon the
person by a lens three inches and a half in diameter and three inches thick
at the centre, and placed at such a distance from the person as to give the
strongest illumination. The illuminating apparatus must be made to move
as the person moves so as to keep him always strongly illuminated.
.
It is desirable to have a black or sufficiently dark back ground to the
person under the stage. It is obvious that any number of spectral figures and
objects may be represented on the stage at the same time. There must be a
screen on the spectators' side of the opening in the stage running the whole
length of the opening, the front edge of which rests on the stage. The screen
must incline upwards and backwards, and it must be sufficiently wide to screen
the opening in the stage as much as possible from the spectators without
interfering with the reflection of the figure. The dimensions given above are
upon the supposition that the spectral figure to be represented is a man of
ordinary stature; they must of course be varied to suit the object to be
represented.