IMPROVEMENTS IN APPARATUS FOR CHANGING DISSOLVING VIEWS
Year: 1884

page_text: I, WILLIAM HENRY DUNCAN, of Coalbrookdale, in the County of Shropshire,
Engineer, do hereby declare the nature of my invention for IMPROVEMENTS IN
APPARATUS FOR CHANGING DISSOLVING VIEWS, to be as follows:-
-
My Invention has for its object, Changing Dissolving Views, and working the
Cocks of Dissolving View Lanterns, by Pedals, moved by the Feet of the Operator;
so as to leave his Hands, and his Eyes free, to use a Book, or written Lecture.
In carrying out my Invention, I employ two Pedals, which are so connected to
the Gas-Cock, or Cocks, and to the arrangements carrying the sets of Pictures, that
the Light can be raised and lowered, and the Pictures fed into the Lanterns, by
alternately pressing down the Foot-Pedals.
In my Dissolving View Apparatus, the Views to be exhibited are carried by
moving Racks, placed on each side of the Lanterns. These Racks are slided along
Guides, which keep them in the same planes, as the slot openings in the Lantern
Tubes, intended to receive the views.
One pair of the set of Racks, is moved forward, at a time, when a picture has to
be changed.
The distance of this travel, is equal to the distance from one view to another in
the rack.
As soon as the Rack movement, has brought a slide, on which is fixed the view,
in position opposite to a groove, placed in line with the slot opening, for the
pictures, a Rod, brought against the edge of the slide, pushes it out of the rack,
into the groove, which conducts the picture, at subsequent movements of the
apperatus, into the lantern Tube, and it shown on the Screen.
Each Slide, after passing through the Lantern, is received into a Rack, situated
on the opposite side. This rack has the same forward movement, as the other, and
brings an empty division in proper position, to receive each slide, at the time
required, so that a rack, filled with pictures, is placed on one side of the Lantern,
each picture, is in rotation, passed through the opticial system, or tube of the
Lantern, and after being exhibited on the Screen, is passed into another rack, on
the opposite side.
In this manner each lantern is served with picture slides.
The working the dissolving Cock, is done, at the proper moments, by the action of
the apparatus and the whole of the movements, required to produce these results,
are performed by Pedals, worked by the Feet.

page_text: In carrying out my Invention, I employ, in connection with the picture racks,
Ratched Wheels, and Pinions, the latter working in toothed racks, placed below the
pictures. The pitch of these wheels, is the same as the distance from one picture,
to another, in the carrying racks. The forward movement of the picture racks, is
given by the pinion Wheels, gearing into the toothed racks, and the pinions receive
their motion, from the Ratchet Wheels, operated upon, one tooth at a time, by a
Lever, worked by the Foot-Pedal.
€
In connection with this motion, I employ a Lever, and Rod, for moveing the
pictures out of the racks, into the groove before named. I also employ a Lever,
which operates a Rod, in connection with the dissolving Cock, by which means, the
gas is turned into, one lantern, and at same time, is lowered in another, at the
required moments, and this Lever, and Rod, are worked by the same Pedal, used to
work the other portion of the apparatus.
The device of the Gas Cock, and system of flexible tubes, is old, and is no portion
of the improvements claimed in this invention.
The arrangement I have described, may be used with three Lanterns, but by
preference, I use the apparatus in combination with two lanterns only.
Refering to my Drawings, Fig. 1. 2. and 3 whose parts are lettered alike, in all
the views. Fig. 1, is a Back Elevation, Fig. 2 is a side Elevation, and Fig. 3 is a
sectional Plan.
The action of the apparatus is as follows.
The left foot of the Operator, being placed on the Pedal A. he presses it slowly
down. The Connecting Rod B attached to this pedal draws down the Lever C,
keyed on the horizontal Shaft D, which gives motion to the Lever E fixed near its
opposite end. A vertical rod F carried through the base plate, and passing up the
back of the Lanterns, to the dissolving Cock G has its weight carried by the end
of the lever E. When this lever is lowered through part of its travel, the rod is
lowered until the stop H rests on the eye I. This lowering of the rod F causes
the projecting stud J, to press down the lever G and turn the dissolving cock K,
whereby the gases are turned off from one lantern, and turned into the other.
This action is done by the foot of the operator pressing down the pedal A,
through a portion of its travel. The remaining part of its travel does not act on
the dissolving Cock, because the lever E is free to continue to descend without the
rod F which rests on the Eye I. During the return motion of this pedal, the Cock
remains unchanged becaused the lever E lifts the Rod F into the position shown in
the drawing without moving the dissolving cock lever, which remains in the
position shown by the dotted line of the drawing.
While the first part of the down travel of the pedal A, is being performed and
its action carried to the dissolving cock in the manner described, the same
movement of the pedal is made to perform a preparatory action, for moving the
pictures forward, but not to actually move them, untill the proper moment comes,
which is, when the return stroke of the pedal A is performed.
This preparatory motion, is as follows. The support L, fixed on the underside of
the pedal A. and holding up the end of the lever M. descends with the lowering of
the pedal, and the lever M follows it, until the back end of this lever is arrested
by the stop N. fig. 2. The Pedal continues to descend, to the end of its travel,
without further affecting this portion of the arrangement.
The first movement of the lever M, turns the shaft O, and the lever P. A
vertical Rod Q is borne up by its end, being supported on the lever P. When this
lever loweres, the rod Q follows it, and draws down the lever R, which turns on the
fixed pivot S, and moves the lever T. To the end of the lever T, a catcher U is
connected, which is drawn backwards the distance of one tooth, of the catcher
Wheel V, when the pedal A is descending through the first part of its travel.
and thus placing the catcher in proper position, for acting on the wheel at
the moment required. The Catcher Wheel V, is keyed on the shaft W, on this
shaft are keyed also the two pinion wheels X and Y. These pinion wheels gear
into the two toothed racks A1 and B 1, fixed on the underside of the picture

page_text: racks C1 and D 1. The Picture racks are carried by the slides E 1. and F 1. also
by G1 and H1 respectively, along which they are moved by the pinion wheels.
After the Pedal A has reached the bottom of its travel, the pressure given by the
Operators. Foot is removed and the spring Il lifts the pedal during its return
stroke. When the Pedal has returned through a portion of its upward travel, the
support L comes into contact with the end of the Lever M and lifting it turns the
shaft O, and lifts the Lever P, which raises the Rod Q and the end of the lever R.
This lever turns on the Pivot S and moves the lever T which action pushes
forward the catcher wheel V through a space equal to the pitch of one tooth. This
action moves the shaft W and the two pinions X and Y. and these pinions gearing
into the racks A1 and B1 move them and the picture racks forward, through a
distance equal to the measure between the centres of the pictures.
In this manner the pictures are all brought in rotation, opposite to the
groove O2 prepared to receive them. and empty spaces in the opposite rack, are
placed in position to receive the pictures after being exhibited on the screen.
When the Pedal A has descended through a portion of its travel, a projecting
Arm J1 working in a slot in the vertical Rod J 2, comes into contact with the end
of the slot, and draws down this rod, until the pedal reaches the bottom of its
travel. The rod J 2 is carried through the base plate to a lever K 2 fig. 1.
This
lever is keyed on a shaft L 2, which has another lever M 2 keyed on its opposite
end. To the top of the lever M 2. a connecting Rod is attached, which gives
motion to the sliding rod N 2. This rod is guided by working in two eyes 02
and P 2. A. Collar Q2, is made fast to this rod. and when this collar is drawn
against the eye O2, or pushed against the eye P 2, the travel is thereby limited in
both directions. That portion of the rod which passes through the eye P 2 has
flat sides the thickness of this part, being the same as the thickness of the pictures.
The edges of the pictures are brought by the rack action in line, with this rod, and
when the pedal A is pressed through the bottom half of its travel, motion is given
to the rod N 2, in the manner already described, and this rod pushes each picture
in turn, out of the carrying rack, into the conducting groove, O2 which guides
them before the light, and subsequently conducts each picture, to the rack on the
opposite side of the lantern.
The return of this rod is effected by the spring P 2. This spring is coiled round
the boss of the Bracket R 2. One end of the spring is made fast to the Bracket,
and the other end pulls back the rod.
To prevent mistake, by the Operator not pressing down the pedals alternately, a
Locking device, is fitted to the apparatus. This device consists of a weighted
Lever A4, oscillating between the two pedals, and worked by projections on the
bottom. This lever is pivoted at B 4, and is provided with two catches, C4
and D 4.
The
When the Pedal A is pressed down to the end of its travel, limited by the
collar Q, coming into contact with the eye P 2. the locking lever A 4. is thrown
over, so that the Ball E 4 leans towards the pedal A, and on the return stroke, this
pedal is held up by the projecting catch C4 falling into the recess F 4
pedal B 3 is thus released, it having been previously held up by the catch. When
pedal B3 is pressed down to the end of its travel, it throws over the Locker, and is
in turn detained. at the completion of the return stroke by the ball E falling
towards this pedal, and causing the catch D 4, to enter the recess G4 as it
previously did the opposite one.
Left Pedal on commencing to
turns Gas on to top lantern.
Bottom lantern being dark,
The order of the various motions is, as follows.
descend, shuts off Gas, from bottom Lantern, and
Also, draws back catcher during first part of travel.
the next half of downward travel changes its picture. First part of pedals' return
draws back picture pushing rod, remaining part of return travel, acts on catcher
wheel, and moves pictures forward, ready for the next change.
These actions are performed in the next lantern, by the action of the next
pedal, B 3, as shown by the drawing,

page_text: Having now particularly described this apparatus, the mode of its action, and
the order in which the various actions are performed, I wish it to be understood,
that I do not confine myself to exact details, or to the picture carrying rack being
made straight, because I may use a circular carrying rack, if preferred; but what
I claim as new, is
First. The Principle, of Changing the picture slides, of a Dissolving View, or
Magic Lantern, by Pedals, moved by the Feet. or by Pedals moved by the
Hands.
Second. The Principle of raising and lowering the light, by Pedals.
Third. The Locking Device, for the Pedals as described.

page_text: I, WILLIAM HENRY DUNCAN, of Coalbrookdale, in the County of Shropshire,
Engineer, do hereby declare the nature of my invention for IMPROVEMENTS IN
APPARATUS, FOR CHANGING DISSOLVING VIEWS, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement :-
My Invention, has for its object Changing the Views, Working the Gas Cock, and
Turning the Limes, of Dissolving View Lanterns by Pedals, moved by the Feet of
the Operator; so as to leave his Hands and Eyes free, to use a Book, or a written
Lecture.
In carrying out my invention, I employ, two, or more Pedals, which are so
connected to the Lime Cylinders, the Gas Cock, and to the arrangement carrying
the sets of Pictures, that the light can be raised and lowered, and the pictures fed
into the Lantern, by pressing down the Foot Pedals.
In my Dissolving View Apparatus, the views or slides, to be exhibited are carried
by four, or more, moveable Racks, two generally being placed on each side, of the
Lantern. These racks, are moved along Guides, which keep them in the same
planes, as the openings in the sides of the lantern tubes, intended to receive the
views. One pair of the set of racks, is moved forward at a time.
The distance of this travel, is equal to the distance from one view, to another in
the rack,
After the rack movement has brought a picture, in position opposite to a groove,
fixed in line with the opening, in the sido of the lantern tube; a Rod, brought
against the edge, of the picture, pushes it out of the rack, into the groove, and at
subsequent movements of the pedals; other pictures are pushed out, of the rack,
and follow cach other in the conducting groove, which guides them, into the
lantern.
After the lantern has shown the pictures, on the screen, the continued passing of
other pictures into the groove, causes those, which have been exhibited to be pushed
into the receiving rack, on the opposite side. This rack, has the same forward
movement, as the other; and brings an empty division, in proper position, to receive
the slides, at the time required; so that, racks filled with pictures, are placed on one
side, of the lantern; each picture is in rotation, passed through the optical systems,
and after being shown on the screen, is passed into a rack on the opposite side.
In this manner, the lanterns are served with picture slides.
The Lime Cylinders, are turned, and also raised slightly, so as to present a fresh
surface continually, to the fame, of the combined gases, at each change of the
pictures.
The working of the Gas Cock, whereby the pictures are dissolved, is done at the
proper moments, by the action of the apperatus; and the whole of the movements,
required to produce these results, are given by pedals, worked by the Feet; or
by Levers, worked by the Knees, or Hands, of the Operator, but by preference, by
pedals worked by the Feet, either direct, or by Electricity.
For moving the picture racks, I employ Levers, which act on ratchet wheels,
keyed on shafts fitted with toothed pinions, which latter, work in toothed racks,
placed below the pictures. The pitch of these toothed racks, is the same as the
distance from picture to picture, in the carrying racks; so that the set of pictures,
is moved forward this distance, each time the catcher wheel, is turned forward, one
tooth,
By these means, the pictures are moved forward, through the exact space
required, and at the right moments, by the action of the Foot Pedals.

page_text: For turning the Limes, I use a ratchet wheel, fixed on a shaft, projecting
outwards, from the back of the Lantern. This wheel, is turned by a lever, in
connection with the Foot Pedal.
For working the Gas Cock, I use levers, and a Rod, which carry the motion of
the pedal, up the back of the lantern, to the cock, and turn it, at the moments
required.
'
The picture pushing Rod, is operated by levers, and rods in connection with the
pedal, in the forward direction, and is 'drawn-backward by a spring.
1
The arrangements I have described, may be used with three lanterns, placed one
over the other, but by preference, I use them in connection, with two lanterns only.
Referring to my Drawings. Fig. 1, Fig 2, and Fig. 3, whose parts are numbered
alike. Fig 1 is a back elevation, Fig 2. is a side elevation, and Fig 3 is a Plan.
The apparatus has eight movements, given by a downward, and upward stroke,
of each pedal, which operate as follows.
The Operator's left Foot, pressing down pedal A. through the first half, of its
travel, causes the connecting rod B. attached to this pedal, to draw down, the lever C.
keyed on the horizontal shaft D, and to give motion, through the shaft, to the
lever E. fixed near its opposite end, A vertical Rod F. carried through the base
plate, and passing up the back of the lantern, to the dissolving lever G. has its
weight carried by the end of the lever E, When this lever is lowered, through a
part of its travel, the rod is lowered, until the stop H. rests on the eye I. This
lowering of the rod F, causes the projecting stud J. to draw down the lever G.
and thus, turn the dissolving cock K. whereby the gases, are turned off, from one
lantern. and turned on to the other.
The remaining part of the pedal's travel, does not act, on the dissolving cock,
because the lever E. is free to descend. through the lower half, without the rod F.
which latter, rests on the eye I. also during the return of the pedal, the cock
remains unchanged, because the lever E lifts the rod F. into the position shown in
the drawing, without moving the dissolving lever G, which remains in the position,
shown by the dotted lines of the drawing.
To the top of the rod F. a Cord A' is attached whose bottom end is connected
to a lever B. working loosely on a shaft C. This lever is fitted with a ratchet-
catch D. which fits into and works the ratchet wheel E. This wheel is fast on
the shaft C. which latter, passes into the lantern, and turns the lime. When the
rod F. is lowered the cord A* and lever B is lowered, and so placed in position,
for turning the ratchet-wheel, and through it the shaft, and lime when the rod F.
is lifted, by the action of the pedal.
While this first part of the downward travel of the pedal A. is being performed,
and its action carried to the dissolving cock, in the manner described, the same
motion of the pedal. is made to give, a preparatory action, to the arrangement for
moving the pictures forward, but not actually to move them, until the proper
moment comes, which is, when the last part of the return stroke, of this pedal, is
made.
This preparatory action, is as follows,
The projecting arm L. carried by the pedal A. and shown holding up, the rod M,
descends with the pedal; and the rod M follows it; until it is arrested by its
stud N, coming into contact with the stop O, on the lantern base. The rod M,
draws down the lever P, turning on the fixed pivot Q. This moves the lever R.
and draws back the catcher S. through a space, equal to the pitch. of the catcher
wheel T.
These parts of the arrangement now rest, while the pedal A descends through
the remaining part of its travel, leaving these parts, in their proper relative
positions, to be acted upon, during the latter portion of the pedals return stroke.
Three movements, are thus performed, with the first half, of the pedals
downward stroke.
When the pedal A. has descended, through this portion of its travel, a projecting
Arm U. working in a slot in the vertical rod V. comes into contact, with the end of

page_text: the slot, and draws down this rod, until the pedal reaches the bottom of its travel.
The rod V. is carried through the base plate up to the lever W (see fig 1). This
lever is fast on the shaft. X, which has another lever Y, fast on its opposite end, To
the top of the lever Y, a connecting rod Z. is attached, which gives motion to the
sliding rod A. This rod is guided by passing through two supports B' and C¹ and
the travel of the rod is thereby limited in both directions. That portion of the
rod A. which passes through the support B', is round in section, the other portion
passing through the support C¹. has flat sides, the thickness of this part being the
same, as the thickness of the pictures, The edges of the pictures are brought by the
rack action (yet to be described) in line with this rod, and when the pedal A. is
pressed down, through the bottom half, of its travel, motion is given by the
arrangement described, to the sliding rod A' and this rod, pushes each picture, in
turn out of the carrying rack, into the conducting groove D¹ (fig 3) which guides
them before the light, and subsequently conducts the pictures to the rack on the
opposite side of the lantern.
This movement is the fourth given by the pedal's downward stroke.
As soon as the pressure of the Operator's foot is released from the pedal A. the
spring E causes it to return to its original position, or it may be lifted by being
looped to the operator's foot, and at same time the spring G¹ draws back the lever W.
turns the shaft X. moves the lever Y. and gives motion to the connecting rod Z.
and so draws the sliding rod A¹ back out of the picture rack, and brings the collar D¹
against the support B¹.
The Spring G₁ is coiled round the projection on the bracket H¹ one end of the
spring is made fast to the bracket, and the other end exerts a strain on the lever,
This fifth movement is performed, during the first half of the pedal's return
stroke; the remaining three motions, are given by the last half of the pedal's return
stroke, They consist of the moving the pictures forward, into position, for the next
change, of lifting the rod, whose weight had previously pressed down the dissolving
cock lever G. and thereby turned down the gases, in the one lantern, and raised
them in the other; and also, of turning the lime.
The forward motion of the picture racks, is effected by the arm L. lifting the
rod M, and turning the lever P. and lever R. which latter moves forward the
catcher S. and catcher-wheel T. which is keyed on the shaft I' on which shaft, are
keyed also, the two pinion wheels. J and K'. These pinion wheels gear into the
toothed racks, L' and M (fig. 1) on the underside of the picture racks. N¹ and O¹.
The picture racks are carried by the guides P¹ and Q₁ also by R¹ and S¹ respectively,
along which they are moved by the pinion wheels J' and K¹.
When the pedal A. is ascending and nearing the end of its travel contact is made
with the end of the arm L. and the rod M. the rod is lifted, and this movement,
acting through the levers P. and R. and catcher S. moves forward the wheel T. turns
the shaft and the pinions J' and K' and these give motion to the two picture
racks N' and O' by gearing into the toothed racks L¹ and M¹.
The pedal is arrested at the end of its travel by coming against the lantern base T'.
at which time the picture racks are both in the required positions, to be acted upon
by the sliding rod A¹ at the next change.
The seventh motion in this system, is given when the pictures are being moved
forward, and is performed by the end of the lever E, coming into contact with the
bottom end of the vertical rod F. and lifting it into position, to allow of the
dissolving cock lever G, being lifted when the cock K is turned in the reverse
direction, by the vertical rod U¹ descending, at the next change of the pictures.
The last movement in this arrangement, is the turning of the lime cylinder, which
is done by the rod F. raising the cord A' and lifting the lever B' and turning the
catcher wheel E' and shaft C which latter has the lime on its opposite end, turned
vertically.
The order of the various motions is as follows.
Left pedal, on commencing to descend, turns down gases from the bottom lantern
1

page_text: ratchet lever, of lime turning arrangement, during the first half of travel. Bottom
lantern being now dark, the next half of downward travel, changes its picture.
First part of pedal's return stroke, draws back the picture pushing rod, remaining
part acts on catcher-wheel, moves the set of pictures forward ready for the next
change; also lifts the rod for turning dissolving cock, into proper position for next
dissolving, with the other rod, at the next change, and also, turns the lime.
These various movements, are performed, in the middle lantern, by the pedal B².
as shown by the drawing.
To prevent mistake by the operator. not pressing down the pedals, alternately.
a Locking Device, is applied, which consists, of a weighted lever A³. oscillating
between the two pedals, and worked by declines, on the bottom portion of the lever.
This locking device, is pivotted at B³. and is provided with two catches C³ and D³.
When the pedal A. is pressed down to the end of its travel, the locking lever A³. is
thrown laterally; so that the ball E³ leans towards the pedal A. and on the return
stroke, this pedal is held up, by the projecting catch Os falling into the recess F³
the opposite pedal being then free to descend, when the pressure of the foot is
applied, which, on reaching the bottom of its travel, moves the locker; so that the
ball is moved to lean in the reverse direction, and on the return of this pedal, the
catch D³, enters the recess G³. and the pedal is locked, until the movement of the
opposite pedal releases it.
Having now particularly described, and ascertained the nature of my said
invention, the mode of its action, and the order and manner in which the various
motions are performed, I wish it to be understood, that I do not, confine myself, to
exact details, or to the picture carrying rack being straight in plan, because I may
use a circular rack, if prefered. I declare, that what I claim, is,
First, The Apparatus, for changing the picture slides, of a Dissolving View, or
Magic Lantern, by Pedals, moved by the Feet, or by Levers, moved by the
Knees, or Hands, of the Operator.
Second The Apparatus for raising and lowering the light by Pedals.
Third. The Locking Device for the Pedals, all substantially as described, and
illustrated by my Drawings, and Specification.
Dated this 18th day of September 1884.