Year: 1886

page_text: I, FELIX JOSEPH VERGARA, of Lordship Lane, Dulwich, in the County of Surrey,
Gentleman, do hereby declare the nature of this invention to be as follows:-
This invention relates to dark slides or apparatus for holding and carrying
surfaces sensitive to light which are exposed in an ordinary camera for the purpose
of obtaining photographic pictures in the usual well known way.
It has for its object a novel method of constructing and arranging such holders
or carriers so that they can be conveniently applied to the purpose of holding
sensitive sheets or films of flexible material, such as paper suitably prepared and
made sensitive, instead of sensitized glass plates as ordinarily used.
My improved film holder consists of a frame or slide, of cardboard, ebonite, wood,
or other sufficiently light and strong material, two opposite edges of which are
provided with grooves or guides fitting upon corresponding guides upon the back
of the camera with which it is to be used, and the guides are so arranged that
the slide can be inverted when desired so that either side can be adjusted next
to the camera.
At the outer end of the slide is a central vertical groove into which slides a
central plate of cardboard, wood, or other suitable material and the groove is
sufficiently wide to allow two thicknesses of the flexible sensitive film which is to
be used to pass freely through it as well as the central plate.
Upon each side of the central groove is made another narrow parallel vertical
groove, into which are fitted two opaque sliding shutters, which may also be made
of cardboard or other material as already described.
These side grooves and the shutters which slide in them are separated from the
central groove by thin sheets or flanges of similar material having openings through
them corresponding with the openings in the slide which determine the size of the
picture upon the sensitive film.
In order to prepare the holder or carrier for use, I withdraw the central slide
and I'take a sheet of the sensitive film of such length as to somewhat more than
cover both sides of the slide, and I fit it upon the latter by folding it transversely
at the centre of its length over the end of the slide, and I then introduce the latter
together with the fold of the film into the central groove and I push the slide into
its place the film being stretched and held steady upon each side of it.
The two shutters being also pushed forward in their grooves upon each side of the
central slide until,closed, the entire holder can be fitted in its place at the back

page_text: of the camera and the part of the film upon one side of the central slide exposed;
the corresponding shutter having been first opened. .
When the picture has been taken and the shutter closed, the holder can then be
inverted so that a second picture may be taken upon the other part of the film
upon the opposite side of the central slide.
The slide or holder made and used in the way described is very simply and
cheaply made, light and easily used, and as each holder contains sufficient sensitive
film to take two pictures, a considerable number of pictures may be obtained with
a moderate number of holders of comparatively little weight, and this method of
using flexible sensitive film is more convenient and requires far less trouble and
care of adjustment, whilst it gives greater certainty of result, than in forms of
arrangement in which a large number of pictures are taken upon a single film
of great length which has to be adjusted and re-arranged after each picture has
been obtained.
The improved holder may be made of cardboard, cemented together in sheets
of the requisite thickness to form the several grooves and flanges, proper openings
being made through them where necessary and in this form it is very light and
cheap; or it may be made of ebonite or of wood, especially where large sized
pictures are to be taken.
Suitable stops may be arranged upon the shutters to limit their movement, and
the openings through which they pass may be made sufficiently impervious to light
in the usual well understood way; and tongues or handles are provided upon the
shutter and slides for their manipulation.
I make the central slide preferably slightly taper in width, so that it may more
readily be introduced together with the folded film into its groove, and the ends
of the latter may be left slightly protruding when the slide is in its place, so that
they may be easily withdrawn with the latter.

page_text: It has for its object a novel method of constructing and arranging such holders
or carriers so that they can be conveniently applied to the purpose of holding
sheets or films of flexible material sensitive to light; such as paper suitably prepared
and made sensitive, instead of sensitized glass plates as ordinarily used.
My improved film bolder or dark slide consists of a frame of cardboard, ebonite,
wood, or other sufficiently strong and light material, the opposite edges of which
are provided with grooves or guides fitting upon corresponding guides upon the
back of the camera with which it is to be used, and the guides are so arranged
that the slide can be inverted, so that either side can be adjusted next to the
camera.
At the outer end of the slide is a central vertical groove into which slides a
central thin plate or slide of cardboard, wood; ebonite, or other suitable opaque
material, and the groove in which it slides is sufficiently wide to allow two
thicknesses of the flexible sensitive paper or other film which is to be used to pass
freely through it together with the central plate.
Upon each side of the central groove is made another parallel groove, into each
of which is fitted an opaque sliding shutter, which may also be made of cardboard
or other material as already described. These side grooves and the shutters which
slide in them are separated from the central groove by thin sheets or flanges of
similar material having openings through them corresponding with the openings
in the slide which determine the size of the picture to be taken upon the sensitive
film.
In the accompanying drawings, which are in illustration of my invention,
figures 1, 2, 3, 4, 5, 6, 7, and 8, represent the improved dark slide constructed
of cardboard. a is the frame, composed of a sufficient number of thicknesses of
cardboard superposed and attached together, so as to form grooves b, b₁ at its
edges. fis the central groove into which fits the central plate or slide e together
with the two thicknesses of flexible sensitive film h. The two side grooves d, d¹,
(figure 2) are separated from the central groove f by the flanges g, g¹, and contain
the two sliding shutters c, c¹.
In order to prepare the holder or carrier for use, I withdraw the central slide e,
and I take a sheet of the sensitive flexible film of such length as to somewhat
more than cover both sides of the slide e, and I fit it upon the latter by folding it
transversely at the centre of its length over the end of the slide e (as shewn in
figures 7 and 8), and I then introduce the latter together with the fold of the film
into the central groove f and I push the slide into its place (as shewn in figures
4, 5, and 6) the film being stretched and held steady upon each side of it.
The two shutters c, c¹, being pushed forward in their grooves upon each side of
the central slide e until closed, (as shewn in figures 5 and 6), the entire holder can
be fitted in its place at the back of the camera, and the part of the film h upon one
side of the central slide e can be exposed, the corresponding shutter c or c¹ having
been opened. When the picture has been taken and the shutter closed, the holder
can then be inverted so that a second picture can be taken upon the other part of
the film h upon the opposite side of the central slide e.
Projecting tongues or handles are shewn by which the slide and shutters can be
opened or closed.
Instead of the central slide e together with the sensitive film h being introduced
into the holder from the same end as the shutters c, c¹, it may be introduced
through a groove at the opposite end, as shewn in figures 9, 10, and 11, which
represent a dark slide similar to that just described, but made principally of wood
instead of cardboard. In these figures a is the frame, having grooves b, b¹. The
sliding shutters are shewn at c, c¹, and e is the central sliding plate to carry the
two thicknesses of sensitive film (not shewn in the figures), the plate e and film
being inserted at the opposite end of the dark slide.
The improved slide or holder made and used in the way described and shewn is
very simply and cheaply made, light and easily used, and as each holder contains
sufficient sensitive film to take two pictures, a considerable number of pictures may

page_text: be obtained with a moderate number of holders of comparatively little weight; and
this method of using flexible sensitive paper or other films is more convenient and
requires far less trouble and care of adjustment, whilst it gives greater certainty
of result, than in those forms of arrangement in which a large number of pictures
are taken upon a single sensitive film of great length which has to be adjusted and
re-arranged after each picture has been taken.
The improved holder made (as shown in figures 1 to 8) of cardboard, in sheets
of the requisite thickness to form the several grooves and flanges, cemented or
otherwise attached together, with proper openings through them where necessary,
is very light, cheap, and convenient. Where made of wood or ebonite, (as shown
in figures 9, 10, and 11), especially where large sized pictures are to be taken, it is
very strong and durable but of somewhat greater weight.
Suitable stops and fastenings may be arranged to limit and regulate the move-
ment and position of the slide and shutters, and the openings through which the
latter pass may be made sufficiently impervious to light by the usual well known
means.
The central slide e may be made slightly taper in width if preferred, in order to
facilitate its introduction, with the film, into the groove; and the outer ends of the
folded film may be left slightly protruding when the slide e is in its place, so that
it may be easily withdrawn with the latter when required.
The apparatus may be made of any desired materials, shape, and dimensions, to
suit the circumstances under which it is to be used. .
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The method of making the sensitive film holder, so that the film upon either
side of the central slide e may be exposed in the camera, substantially as described
and shewn.
2. The method of using the sensitive film by folding it over the central slide e
before inserting the slide in the holder, substantially as described and shewn.