Improvements in Apparatus for Exhibiting Magic Lantern Views in Series.
Year: 1893

page_text: Date of Application, 6th Oct., 1893
Complete Specification Left, 6th July, 1894-Accepted, 6th Nov., 1894
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Exhibiting Magic Lantern Views
in Series.
I, JASPER WETTER, Patent Agent, of 433 Strand, in the County of London,
me by
do hereby declare the nature of this invention, communicated to
Emil Scheitlin, Mechanician, of St. Gall, Switzerland, to be as follows:-
This invention relates to magic lantern apparatus suitable for successively
projecting a series of lantern views on a screen or other base.
The plant embodying the present improvements, or some of them, is preferably
placed in two rooms, the first room containing a cylindrical or polygonal frame
carrying a series of transparent glass slides suitable for magic lanterns; a magic
lantern placed before the frame, so that by turning the said frame on its vertical
axis, the said slides or transparencies are successively placed into the position
necessary to project a good image; and a clockwork mechanism placed in the
interior of the said cylindrical frame and adapted to turn it intermittently, so that
each view remains at rest for a given time, for instance of a minute.
The second room is a dark room, with a hole in the wall or partition which
divides it from the first, so as to allow the lens-tube of the magic lantern, or the
bundle of light, to pass from the first room into the second, while the opposite wall
or partition is covered by a screen or other suitable base adapted to receive the
image from the magic lantern.
The cylindrical or polygonal frame mentioned above is mounted on a vertical
shaft, which runs on a ball-bearing or well-lubricated step-bearing, and is also
guided at the top by a ball-bearing, in order to reduce the friction.
The clockwork, which imparts motion to the frame, is preferably placed in
proximity to the vertical shaft, so that the said frame revolves around the clock-
work, the motive power being a weight or a pair of weights, which is periodically
drawn up by means of a crank and a rope wound on a drum.
To render the motion of the frame intermittent, the clockwork or driving
mechanisin may contain a horizontal disc, the circumference of which has three
notches at equal distances from each other, and also a hub mounted on a horizontal
When one of the
axle and provided with three radial arms placed at 120° apart.
said arms during its downward motion comes in contact with the said disc, it cannot
pass further, until one of the notches of the disc arrives in the plane of the said
arm, and allows the latter to descend. Thereupon the frame will continue to turn,
until the succeeding lever arm comes into contact with the disc. The intervals of
rest may be shortened or increased by regulating the length of the pendulum, or
by varying the number of recesses in the circumference of the disc.
To prevent irregular oscillations of the frame or ring which carries the views etc.,
1 employ an electro-magnetic stopping and releasing device, comprising a weighted
angle lever, provided with a friction roller, which rolls on the inner circumference
of the cylindrical frame, until it meets a recess of the same, and enters, owing to
the weight of the angle lever, and thereby prevents or limits any motion of the
frame to the right or to the left. From this point the lever is subsequently
released by an electro-magnet, the exciting circuit of which is automatically closed,
every time the notched disc mentioned above resumes its rotary motion, or every
time the disc has turned through a given angle.
Names or other suitable words or figures may be combined with the magic

page_text: lantern views, by providing a narrow opening or slot above or below the place
occupied by the transparent lantern plate through which pass the rays, and causing
the corresponding names to appear before the said slot, the strips or plates carrying
the said names being propelled by the same clockwork which moves the cylindrical
main frame, or by a special clock mechanism. The starting and stopping of the
strips bearing the names, whether arranged as described above, or in any other
suitable manner, may be controlled by the same electric circuit and contact, which
periodically releases the weighted angle-levers mentioned above. Said strips may be
placed behind the screen and propelled by weights combined with ratchet
mechanism.
In order to mask the change of views, automatic shutters or obscuring devices
may be set in action at every change, so as to intercept the rays between the lens
and the pictures, while the change takes place, and the same agencies may be
employed, either to switch off the current of the electric lamp, or to screen the
lamp.
Special tints may be imparted to the different views, by causing the light to pass
through exchangeable or movable glass plates having the desired colour.
in
Two magic lanterns may be placed on a pair of stationary stands diametrically
opposite each other, and project their images on opposite sides of the dark room,
which the apparatus is placed.
It may be convenient, to mount the views on an endless apron passing over two
or more polygonal drums, which receive rotary motion, instead of mounting them on
a single revolving drum or frame.
Dated this 6th day of October 1893.
FAIRFAX & WETTER,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Apparatus for Exhibiting Magic Lantern Views
in Series.
I, JASPER WETTER, Patent Agent, of 433 Strand, in the County of London,
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 :-
This invention relates to magic lantern apparatus suitable for successively
projecting a series of lantern views on a screen or other base.
The plant embodying the present improvements is preferably placed in two
rooms, the first room containing a cylindrical or polygonal frame carrying a series
of tranparent glass slides suitable for magic lanterns, a magic lantern placed before
the said frame, so that by turning the said frame on its vertical axis, the said slides
or transparencies are successively placed into the position necessary to project a
good image; and an automatic driving mechanism with regulating clock placed in
the interior of the said cylindrical frame or in any other convenient position and
adapted to turn it intermittently, so that each view remains in front of the lantern
for a given time, for instance of a minute.
The second room is a dark room, with a hole in the wall or partition which
divides it from the first, so as to allow the lens tube of the magic lantern, or the
bundle of light, to pass from the first room into the second, while the opposite wall
or partition is covered by a screen or other suitable base adapted to receive the
image from the magic lantern.
Names or other suitable words or figures may be combined with the magic
lautern views, by providing a narrow opening or slot above the place occupied by
the transparent lantern plate through which pass the rays, or below the place

page_text: on a vertical smart
means of spoke
D is the lantern mounted on a telescopic post E and thereby rendered adjustable
in height.
F is the casing of the gravity motor and clockwork propelled by a weight and
provided with a pendulum f.
Figs. 3 and 4 represent a device for locking the frame A in position at given
intervals of time.
The ring A (which in Fig. 4 is shown straight instead of circular) has on its
inner circumference a series of teeth a' and depressions, the teeth being alternately
placed back to back and front to front with an interval between.
Into the said interval between two tooth faces fits the upper end of a lever K,
placed in front of an electro-magnet J mounted on a column or telescopic
stand H.
If the lever K is in the position represented by Figs. 3 and 4, and the electric
circuit passing through the exciting coil of the magnet J is closed, the lever K will
be attracted, so as to disengage its extremity from the teeth a¹ and allow the
ring A to turn on its axis under the influence of the propelling weights. When
the exciting circuit of the electro-magnet J is broken, the lever K will drop back
and fall between two teeth a' a', thereby stopping the motion of the ring A, until
the exciting circuit is again closed.
I prefer to use the lever K in duplicate, that is to say, two electro-magnetic
disengaging devices acting on two diametrically opposite points of the ring A.
Fig. 5 is a side elevation and Fig. 6 a front elevation of an automatic name
indicator placed behind the screen L provided with a horizontal opening through
which the names can be seen one after the other. These names are printed on
narrow plates m, m, mounted on a pair of endless chains or bands which are guided
over two pairs of prisms M, M, one at the top and one at the bottom, the upper
pair serving also for propulsion. The axle of the upper prisms is set in motion
by a weight N through the intermediary of ropes, a pair of drums n, n and tooth
wheels, as shown by Fig. 6, but this motion can only take place, as long as the
escapement wheel m' connected with the upper prisms will allow it, and as this
escapement wheel is controlled by a pawl or anchor under the influence of an
electro-magnet, the motion of the endless chain will be in accordance with the
periodical closing and breaking of the electric circuit which excites the said electro-
magnet.
The name plates m which appear behind the opening are illuminated from

page_text: behind by a pair of gas flames as shown in Figs. 6, or in any other convenient
manner.
Fig. 7 shows an example of an ordinary electro-magnetic clock escapement
applicable for regulating the motion of the indicator, P being the anchor, Q the
electro-magnet, and p an antagonistic spring. Instead of the electro-magnetic
disengaging lever described above, an electro-magnetic escapement may be used
also for regulating the motion of the slide-carrying ring, the ordinary escapement
anchor being replaced in this case by a balance lever turning on a horizontal axle
and having at each end a vertical pin, and the teeth a' of the ring A being replaced
by a circle of pin holes formed in the horizontal part or flange of the ring A. When
the said balance lever turns on its axis, the said pins enter alternately the holes of
the ring A., and act on it in the same manner, as an ordinary escapement anchor
acts on the escapement wheel of a clockwork.
For closing and breaking the electric regulating circuit or circuits at regular
intervals by means of a clockwork, any suitable device may be used, for instance, that
shown by Fig. 8, which acts at the same time on two electric circuits, one for the ring A
and one for the indicator. This device chiefly comprises a wheel k caused to turn
slowly on a horizontal axle by the pendulum of the clock, and provided with two
diametrically opposite pins r, a contact lever S turning on a fulcrum & and carrying
a pair of contact springs ss2, said lever being adapted to make contact with the
screw T and with the screw t, twice during every revolution of the wheel, k by
means of the pins r.
Both circuits include the fulcrum and the lever S, and when the circuits
are closed, one current passes through the lever S and the springs' to the screw T
and out through the terminal T', while the other passes through the lever S, and
spring to the terminal t.
If the driving mechanism of the frame A and of the name indicator are SO
arranged, that both should work for the same length of time after each interval,
the electro-magnets which control the motion of the said driving mechanisms may
be included in the same circuit, and the contact device will be simplified.
intervals of rest may be lengthened or shortened by varying the length of the
pendulum.
The
Instead of using an electro-magnetic regulating device, the same effect may be
obtained by purely mechanical means, for instance that indicated in Fig. 1, where
the motion of the clockwork is transmitted through an inclined shaft and bevel
wheels to a notched disc mounted on the column H. In this case the ring A has as
many short vertical arms a¹, as there are lantern slides, and the motion of the
ring A is stopped each time by one of the said arms which slides with its bent lower
extremity (armed with a friction roller) upon the said disc, until it enters one of
the said notches and thereby allows the ring A to turn on its axis, until the
following arm (a¹) comes in contact with the disc G.
I do not, however, claim this special regulating device, as others may be easily
devised for the same purpose, nor do 1 claim any special construction of regulating
clock.
As it is important, that each lantern slide should occupy the correct position in
the magic lantern, and that any irregularity in this respect can be rapidly adjusted,
each of the slides is mounted in a specially constructed frame suspended from the
ring A in the manner represented by Figs. 9 and 10 on a larger scale, Fig. 9 being
a vertical section and Fig. 10 an inside elevation of a slide and frame.
The said frame is composed of a wire U bent so as to form a horizontal hinge
pin or pivot and a pair of vertical guides, provided at the lower ends with screw
threads and nuts; a pair of grooved guide rails or channel irons V, V ; and a pair
of helical springs u are coiled around the said guides above the upper rail V, so as
to press the latter against the upper edge of the slide. The said frame is suspended
freely from a plate W, hinged at the upper end to a horizontal plate Y, extending
radially from the ring A, and secured to the same by a pair of screws passing
through a slot (not shown). The plate W rests against a set screw fixed in the

page_text: vertical plate X, so that by turning the latter, the radial distance of the slide B
from the axis of the ring A may be regulated.
For removing the lantern slide B from its frame and inserting a fresh slide, it is
only necessary to lift the rail V, by compressing the springs u.
The source of light in the magic lantern is preferably an incandescent gas lamp,
which instead of the ordinary glass cylinder has a metallic cylinder, with an
opening in front, through which the rays reach the lens serving to concentrate the
light upon the transparent glass slide.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is ;-
1. In apparatus for exhibiting a series of magic lantern views, the combination
of a magic lantern or analogous optical instrument, with a movable frame carrying
a series of lantern slides in such a position that the motion of the said frame places
the said slides consecutively in their correct position in the lantern, mechanism for
imparting to the said frame an intermittent motion, a screen adapted to receive and
show the image projected by the lantern, and an automatic name indicator operated
in unison with the driving mechanism of the frame, so as to show simultaneously
with each lantern image the corresponding name, substantially as described.
2. In apparatus for exhibiting a series of magic lantern views by means of a
movable slide-carrying frame and an automatic name indicator, the combination of
driving mechanism adapted to impart a continuous motion to the slide-carrying
frame and to the indicator, with electric regulating apparatus adapted to alternately
stop and release the said frame and indicator, and a clockwork adapted to break
and close the electric circuit or circuits of the said regulating apparatus at regular
intervals of time, substantially as described, and for the purpose specified.
3. In apparatus for exhibiting magic lantern views in series, the combination of
an electro-magnetic escapement mechanism adapted to control the motion of the
lantern slides, with an automatic name indicator mounted behind the screen and
provided with an electro-magnetic escapement mechanism, and an electric
regulating circuit and clock adapted to operate the said escapement mechanisms,
substantially as described and for the purpose specified.
4. In apparatus for exhibiting magic lantern views in series, a revolving frame
from which the lantern slides are suspended vertically by means of adjustable
holders hinged at the top, substantially as described.
Dated this 5th day of July 1894.
FAIRFAX & WETTER,
Agents for the Applicant.