IMPROVEMENTS IN DOUBLE DARK SLIDES FOR. USE IN CAMERAS FOR PHOTOGRAPHIC PURPOSES
Year: 1884

page_text: Photographic Purposes.
I IRAEL TODD, of North Parade Otley in the county of York Photographer do
hereby declare the nature of my Invention for "IMPROVEMENTS IN DOUBLE DARK
SLIDES FOR. USE IN CAMERAS FOR PHOTOGRAPHIC PURPOSES," to be as follows :-
The object of my invention is to construct dark slides, which are simple in
construction, effective, and totally exclude all light.
I construct my.slide with the edges and ends of the frame, solid or closed, so as
not to admit any light whatever, that portion of the frame, admitting the sliding
shutters is on one side smaller than the size of plate to be used, the opposite side
is sufficiently large to admit the size of plates, for which the slides are constructed,
the plates resting on the inside of the smaller shutter frame, and retained in
position by projections or adjustable catches, or other suitable means, both plates
are inserted in position in the dark slide, through the larger aperture which is
then closed by the larger shutter. Betwixt the plates of glass, is inserted a sheet
of an opaque substance, with a spring or springs, to press each plate home in the
slide..

page_text: Improvements in Double Dark Slides for. Use in Cameras for
Photographic Purposes.
J ISRAEL TODD of North Parade Otley in the county of York, Photographer,
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 :-
The object of my invention is to construct double dark slides, or double backs
in a more simple and effective manner, so as to totally exclude all light from
entering the interior of the same, in the said double dark slides or double_backs to
hold in position and keep in darkness sensitive plates or other sensitive material
until required to be exposed to the action of light; and also after such exposure
to the light to retain in darkness the said sensitive plates or other sensitive
material so long as may be deemed necessary.
I construct my double dark slides or double backs of wood or other suitable
material, the framework (ends and sides) of the same being solid or closed-so as to
prevent the light from entering the interior or to exclude the light, the interior of
the said double dark slides or double backs is a little longer and wider than the
length and width of the plates to be used and the depth of the said interior is more
than the thickness of the plates, so that a thick and thin plate may be used at the
same time. Grooves (as ordinary) are made in the inner sides of the framework
and the end, in contradistinction; opposite to the one where the slides are inserted;
the slides fit into these grooves and may be inserted, withdrawn or adjusted by
means of projections on the ends of the slides; the portion or end of the framework
admitting the slides is on one side smaller than the size of the plates to be used;
the opposite side is sufficiently large to admit the size of plates for which the said
alides are adapted, The sensitive plates or other sensitive material between which
may be placed a thin sheet of metal, (with springs attached) or other suitable and
opaque substance are deposited through the larger aperture into the interior of the
said double dark slides or double backs, when so placed they rest on. flanges or
projections formed on that side having the smaller aperture; at the same time
allowing sufficient space between the plate and the smaller slide in order to prevent
rubbing. The plates are fixed and kept in position by additional flanges or
projections at the end where the slides are inserted and adjustable catches placed
at or near the other end, and so prevent the larger slide from rubbing the plate.
At the end where the slides are inserted I attach a turn knob or button with
which to fasten the slides when closed or fully inserted, and with which to
withdraw the double dark slides or double backs from the camera.
Decem
DRAINAS

page_text: Fig. 3, shews the slides closed with the turn knob or button in position to allow
the slides to be opened.
Fig. 4, is a plan of framework as shewn in Fig. 1, the slides being closed, with
the turn knob or button in position to allow the slides to be opened.
Fig. 5, shews section of frame. A is the framework of my improved double dark
slides or double backs. B are the grooves into which the slides fit, and in which
they are moved up and down as desired, C are the projections by which to move
up and down slides in their respective grooves. D is the smaller slide forming the
back of my improved double dark slides or double backs, E is the larger slide,
F are the flanges or projections on which the plates rest when placed in position,
G are the additional flanges which in conjunction with flanges F and the adjustable
catches H prevent the plates from rubbing on the slides. H are the adjustable
catches which can be turned on their pivots and hidden in the framework A as.
desired. K is the turn knob or button with which to secure the slides when the
same are fully inserted or closed, and with which to withdraw the double dark
slides or double backs from the camera. L is the framework end between the
slides and may be solid like the framework or an additional piece of wood, or other
suitable material may be placed upon the framework, the object being to more
effectually exclude the light.
. 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 general arrangement and construction of double dark slides or double
backs as shewn and described.
(2.) The use and employment of flanges G and adjustable catches H as and for
the purposes specified.
(3.) The construction of a solid frame having two slides one being less than the
other, as and for the purposes specified.
(4.) The use and employment of turn knob or button K and projections C, as
and for the purposes specified.
Dated thin 17th J. of Cantambor 1005
JOHN E. WALSH,
30, East Parade, Leeds,
Agent for the Applicant.