IMPROVEMENTS IN MAGIC LANTERNS to be as follows:-
Year: 1884

page_text: We CHARLES GRAY of 11 Crooked Lane and HENRY KEMP of 7 Thavies Inn
both in the City of London Opticians do hereby declare the nature of the said
invention for "IMPROVEMENTS IN MAGIC LANTERNS to be as follows:-
"1
This Invention relates to that portion of Magic Lanterns in which the Magic
Lantern slides are placed for exhibition and has for its object the enabling the
Exhibitor whilst one mounted slide is being exhibited to place in their proper
position in the Lantern a second or other number of slides in readiness to be
exposed to the light of the Lantern without necessitating the withdrawal of the
preceding mounted slide from the slide holder whilst it is opposite the lens as
is the case with Magic Lanterns of the ordinary construction provided with a fixed
slide holder.
Now our Invention consists essentially in substituting a shifting slide holder
capable of holding two or more properly adjusted Magic Lantern slides at the same
time for the fixed slide holder usually attached to Magic Lanterns and which will
only hold a single slide.
The said shifting slide holder is by preference made to slide in a vertical
direction, is provided with separate spaces or openings for accomodating two or
more slides at a time and furnished with any convenient self acting or other catch
for fixing it in its adjusted position during the exhibition of any particular slide,
and for releasing it when the succeeding slide already adjusted in its place in
the slide holder is to be exposed to the light of the Lantern. The shifting of the
slide-holder may also if desired be made to actuate a screen or partial obstructor
situate in front of the lens for the purpose of producing an effect approximating to
that of what are known as dissolving views.
1. OOA
EDWIN P. ALEXANDER, !
Fel, Inst. P.A.,
Agent.

page_text: Improvements in Magic Lanterns.
33
We CHARLES GRAY of 11 Crooked Lane and HENRY KEMP of 7 Thavies Inn
both in the City of London, Opticians, do hereby declare the nature of our
invention for "IMPROVEMENTS IN MAGIC LANTERNS 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 that portion of magic lanterns and similar apparatus in
which the picture or object slides are placed for exhibition and has for its object
the providing a simple and cheap arrangement for enabling the exhibitor whilst
one picture or object slide is being exhibited to place in proper position in the
Lantern above or below the optical axis thereof a second or other number of slides
whether mounted in frames, or unmounted and contained in the usual "carrier," in
readiness to be exposed to the light without necessitating the withdrawal of the
preceding picture slide from the slide holder whilst it is opposite the lens as is
the case with magic lanterns of the ordinary construction provided with a fixed
slide holder.
Now our invention consists essentially in substituting a moveable or shifting
slide-holder capable of being raised and lowered either vertically or at an angle
across the optical axis of the lantern and of holding two or more properly adjusted
magic lantern slides at the same time disposed one above another for the fixed
slide-holder usually attached to magic lanterns and which only holds a single
properly adjusted slide therein.
The said moveable or shifting slide-holder may be made to slide either in an
upright or vertical direction or at such an angle as will admit of its being divided
into compartments disposed one above the other as and for the purpose hereinafter
mentioned but we prefer in practice that it should be made to slide vertically and
be provided with separate spaces or openings for accomodating two or more
mounted slides, or "carriers" for mounted slides at a time situate one above
another and be furnished with any convenient self acting or other catch or catches
for arresting and holding it in its adjusted position during the exhibition of any
particular slide and for releasing it when the succeeding picture slide (already
adjusted in its place in the slide holder, above or below the lens as the case may
be) is to be exposed to the light of the lantern. The upward or downward shifting
of the slide-holder may be effected by hand direct or by any well known
mechanical arrangement and may obviously if desired be made to actuate at the
same time a screen or partial obstructor as is well understood situate in front of
the lens for the purpose of producing an effect approximating to that of what are
known as dissolving views.

page_text: Figure of of the drawings hereunto annexed represents a front elevation of a
magic lantern having our vertically adjustable slide-holder applied thereto.
Figure 2 is a corresponding side elevation of the same and;
Figures 3, 4 and 5 are details of the moveable or shifting slide-holder detached
here shown as adapted for holding two magic lantern slides in separate compart-
ments, one above the other, at the same time.
a is the body of the lantern which contains the usual lamp and lenses for
intensifying the light thereof, which being well understood need not be further
referred to or shown in the drawings. b is our improved moveable or shifting
slide-holder the drawings show it as adapted for holding two slides only inserted
from the side of the lantern. This shifting slide-holder is here shown as sliding
vertically between the body of the lantern and a plate c fixed to the support d
which carries the usual adjustable lens tube e with its adjusting arrangement f.
The said shifting slide-holder is by preference formed with longitudinal flanges g
and h at its front and rear sides engaging respectively with the edges of the plate c
and the sides of the lantern body so as to guide it in its upward and downward
movements. The interior of the shifting slide is divided into two or more separate
compartments by one or more horizontal transverse partitions or ledges i for
supporting the picture or object slide or slides contained in the said slide-holder.
kare the usual yielding plates pressed outwards by springs ll for holding mounted
picture or object slides or the usual "carrier" for unmounted slides steady when
inserted into the slide holder. m is a spring catch engaging into a hole or notch
in the front of the shifting slide-holder for the purpose of arresting its movement
and holding it securely when brought into proper position as shown in figures 1
and 2, and releasing it when the slide-holder is to be shifted. n is a handle
attached to the top of the shifting slide-holder for actuating the same by hand
direct. In using our improved arrangement the picture or object slide to be
exhibited is contained for example in the lower compartment o of the shifting
slide-holder as shown in the drawings, immediately behind the lens, and whilst
this is being exhibited the succeeding picture slide is introduced into the upper
compartment o' and properly adjusted in readiness for exhibition in its turn by
the descent of the slide-holder to the proper distance required or until arrested by
the spring stop or catch. Whilst this is on view the previously exhibited picture
slide which has now been brought below the lens is withdrawn and replaced by
another in readiness for exhibition by the sudden raising of the slide-holder till it
is caught at the proper elevation by the self acting spring catch m and so on the
changing of the pictures being rapidly accomplished by the up and down move-
iment of the slide-holder without the objectionable effects on the screen which
result from the use of the usual stationary slide-holder wherein the picture slides
are introduced and adjusted in succession whilst opposite the lens.
We are aware that it has been proposed to use in connection with Magic
Lanterns moveable slide-holders shifted horizontally across the optical axis of the
Lantern and divided into compartments arranged side by side containing two or
more unmounted picture slides on one and the same horizontal base, but such
arrangements are not conveniently applicable for the exhibition of the usual
picture slides inserted horizontally from the side of the Lantern or of special slides
such as Chromotropes, moveable slides, panoramas and the like, and are moreover
both complicated and costly in their construction therefore we lay no claim
thereto.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is
1. The application and use to and in Magic Lanterns and apparatus of an
analogous nature of shifting slide-holders moveable in an upward and downward
direction between guides as and for the purpose specified.

page_text: 2. The use in connection with a Magic Lantern or similar apparatus of a shifting
slide-holder moveable in and upward and downward direction between guides and
arranged so as to allow of the introduction and proper adjustment therein above or
below the optical axis of the Lantern of one or more picture or object slides in
reserve without interfering with the particular slide under exhibition as specified.
3. The combination with an upward and downward shifting slide-holder for
Magic Lanterns and similar apparatus of a self acting or other catch or stop for
arresting its movement and holding it in its changed position thereby facilitating
the rapid change of the pictures exhibited, as specified.
Dated this 15th dow of A 19RK