IN PHOTOGRAPHIC CAMERAS
Year: 1881

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
"IMPROVEMENTS
County of Middlesex, Patent Agent, for an Invention of
IN PHOTOGRAPHIC CAMERAS." A communication from abroad by E. Enjalbert,
of Montpellier, France.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 12th November 1881.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN PHOTOGRAPHIC CAMERAS."
[A communication from abroad by E. Enjalbert, of Montpellier, France.]
This Invention relates to an improved photographic camera, which is especially
suitable for groups, landscape, and other outside work, as it is made to contain
within itself a supply of sensitised dry plates in readiness to be exposed in
the camera in any desired order, the whole forming a compact and portable
apparatus.
The Invention consists mainly in the combination with the camera of a box to
hold a number of sensitised plates, the said box occupying the position of the dark
slide, and being fitted to slide in and out through an opening in one side, top or
bottom of the camera, so as, in connection with the means hereafter described, to
enable any one of the plates to be exposed in the camera as required. This plate
box is open at the inner end only, and the sensitised plates are fixed in separate
frames which are fitted to slide side by side in grooves in the plate box, and
together exactly fill the said box so as to prevent the entrance of light.
The camera at the side opposite to that through which the said plate box slides
has a door upon which are mounted a number of screw studs or other suitable
catches respectively opposite to the plates in the plate box, and adapted to screw
into or engage with the frames of the said plates, so that when any one of them
is so engaged, and the plate box is drawn outwards at the opposite side, the
corresponding plate will be withdrawn from the plate box and held in position in

page_text: the camera, being retained at one end by the said stud or catch, and at the other
end by the frame remaining engaged in the grooves of the plate box.
The camera itself has grooves opposite the several plates in the box to receive
the ordinary focussing-screen of ground glass which is inserted through the door-
way above mentioned into the grooves, corresponding to the plate to be exposed.
When not in use the focussing screen is received in a separate groove alongside the
plate box. The plate box cannot be wholly withdrawn at the side, through which
it works as above described, but it may be removed through the doorway above
mentioned and replaced by another filled with sensitised plates when those in the
first box are all used.
The camera is preferably of the ordinary "bellows" form, and the front in which
the lens is mounted is provided with a mechanical double slide for adjusting the
lens to any desired position with respect to the centre of the camera. When in
use the front of the camera is fixed to one end of a mechanical slide, whose other
end is fixed to the back of the camera so as to be readily detached and packed up
with the camera. This mechanical slide is for the purpose of focussing, and is
provided with a scale graduated in reference to the plates in the plate box, so that
when the same picture is to be photographed again on another plate it is not
required to use the focussing screen for each plate.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alexander Melville Clark in the Great Seal Patent Office on the
12th May 1882.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN PHOTOGRAPHIC
A communication from abroad by E. Enjalbert, of Montpellier, France.
CAMERAS."
This Invention relates to an improved photographic camera which is especially
suitable for groups, landscape, and other outside work, as it is made to contain
within itself a supply of sensitised dry plates in position to be exposed in
the camera in any desired order, the whole forming a compact and portable
apparatus.
The Invention consists mainly in the combination with the camera of a box
holding a number of plates, and occupying the position of the dark slide, the box
being fitted to slide in and out through an opening in one side, top or bottoin of
the camera, in order that the plates which it contains may be successively exposed
as hereafter described. This box is open at the inner end, and the plates are fixed
in separate frames fitted to slide side by side in grooves in the box, and which
collectively exactly fill the said box so as to prevent the entrance of light during
the exposure of any one of the plates, or when the box is removed from the
camera. The camera at the side opposite to that through which the said plate
box slides has a door fitted with a number of screw studs or other suitable catches
respectively opposite to the plates in the plate box, and adapted to screw into or
engage with the frames of the said plates, so that when any one of them is so
engaged, and the plate box is drawn outwards at the opposite side, the corresponding
plate will be withdrawn from the plate box. The plate so withdrawn will then
be held in position in the camera by its frame being retained at one end by the
said stud or catch, and at the other end by remaining engaged in the grooves of
the plate box. The plate box cannot be wholly withdrawn at the side through
which it works, as above described, but may be removed through the doorway
above mentioned and replaced by another filled with sensitised plates when those
in the first box have all been exposed.
The camera itself has grooves to receive the ordinary focussing screen of ground
glass which is inserted through the doorway above mentioned into grooves corre-
sponding to the plate to be exposed. When not in use the focussing screen is
received in a separate groove alongside the plate box. The camera is preferably
of the ordinary "bellows" form, and the front in which the lens is mounted is
provided with a mechanical double slide for adjusting the lens laterally and
vertically as usual. When in use the front of the camera is fixed to one end of a
mechanical slide whose other end is fixed to the back of the camera.
mechanical slide is for the purpose of focussing, and is provided with a scale
graduated in reference to the plates in the plate box, so that when the same
picture is to be photographed again on another plate it may be readily focussed
upon this other plate without again using the focussing screen.
DESCRIPTION OF DRAWINGS.
This
Figure 1 is an elevation of the camera showing the door with the screw studs
fitted therein, and also the mechanical slide which connects the front and back of

page_text: .
showing the sliding plate box drawn out, leaving a plate in a position to be exposed
in the camera.
A is the plate box, fitted to slide light-tight in and out through an opening at
the side of the body B of the camera, as shown in Figure 3. It has lugs a at top
and bottom, which slide in grooves b and prevent the box being completely drawn
out. The outer end is closed and provided with a handle Ã¹. C are the plate
holding frames having rebated openings, in which the plates are held by buttons.
These frames C fill the box light-tight, and their top and bottom edges are
rebated and slide in grooves a¹, a², a³, a, &c., in the top and bottom of box A, and
are provided with springs c to make them slide sufficiently tight to prevent their
falling out. D is a door at the side of the body B facing the inner or open end of
the box A, at which doorway the said box can be wholly removed; E are a series
of thumb screws opposite the ends of the frames C respectively. These screws
traverse a box fitted into the door D, and are capable of being screwed into corre-
sponding female screws c¹ let into the edges of the frames C, as shown partly in
section in Figure 3, which represents the box A drawn out, and one fraine C with
its plate in position for exposure. The screws are furnished with springs e to
prevent them accidentally engaging with the frames and with collars e¹ to limit
their motion. E' is a loose screw for withdrawing the plates from the box when
removed from the camera. d are air holes in the door so arranged as to prevent
the entrance of light. F is the focussing screen, and 61, 62, 63, &c., are grooves in
the camera B in the same planes respectively with the frames C, in any of which
-the-screen-may-be-placed-for-the-purpose-of-focussing,-when-the-box-A-is-drawn
out without any of the frames C being engaged with screws E; G is a mechanical
slide worked by rack and pinion, and connecting with the front H and back B of
the camera by sets of button hole slots y engaging with studs g', or by dovetail
brackets g received in sockets g³, and secured by binding screws g, according as
the slide G is connected to the bottom or side of the camera; I is a scale upon
the slide G graduated to correspond to the distances between the plates in the
frames C.
Having described the nature of the said Invention and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
herein before in part recited Letters Patent is,-
1st. The combination with a photographic camera of a plate holding box which
is open at the inner end and closed at the outer end, and fitted to slide in and out
of the camera as described, and of a series of plate holding frames fitted to slide
in and out of the box, substantially as and for the purpose shown and described.
2nd. The combination with a photographic camera of a sliding plate holding
box, sliding plate holding frames fitted in said box, and of the means shown and
described for retaining any one of the frames, and causing it to be drawn out of the
box and held in position for exposing when the box is drawn outwards, substantially
as shown and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Twelfth day of May. A.D. 1882.
A. M. CLARK. (L.S.)