Improvements in Apparatus for Developing Photographic Plates.
Year: 1894

page_text: Date of Application, 21st Nov., 1894
Complete Specification Left, 20th Aug., 1895-Accepted, 2nd Nov., 1895
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Developing Photographic Plates.
I, EMILE POULENC, of 92 Rue Vieille du Temple, Paris, in the Republic of
France, Manufacturer, do hereby declare the nature of this invention to be as
follows:-
My invention relates to apparatus for developing photographic plates.
According to my said invention I construct a portable developing box in which
photographic plates can be developed at any spot in full light. By my improved
apparatus, which is not much bulkier than an ordinary dark-slide, I can develop
and if necessary fix immediately after the exposure and in full light and away from
any dark-room.
This apparatus has the general form of a frame; it is constructed in such a
manner that the photographic plate may be easily introduced into the same without
risk of being exposed to the light, and when once in the box the photographic
plate is perfectly visible from the outside through sides of coloured glass, which
enable the progress of development to be followed with the greatest facility while
the photographic plate is kept protected from chemical rays.
The improved box can be easily dismounted and can therefore be cleaned interiorly
in all its parts, which is an essential condition for the success of the operations; at
the same time precautions are taken for ensuring complete tightness, although the
sides of glass with which the box is provided are removable; this removableness
facilitates the cleaning and permits of the rapid replacement of the glass plates
which may break.
By suitable arranged devices the developing box can be rapidly filled and emptied
in succession with different liquids if desired, so that I may not only effect the
development and the washing of the photographic plate, but also the fixing of the
same without taking it from the developing box.
For the introduction of the photographic plate into the developing box I make
use of a special auxiliary frame, into which is caused to pass, after the exposure,
the photographic plate contained in the negative frame; this last operation is
effected below any black cover with which the whole is surrounded, without any
necessity for passing into a dark room. This auxiliary frame, which constitutes
a kind of intermediary gate between the dark-slide and the developing box, is
arranged so as to fit upon a removable part placed above the developing box and
forming an automatic shutter and when it is once in this position the photographic
plate may be caused by a very simple movement to drop rapidly into the
developing box.
This special frame can moreover be so arranged as to serve as a dark-slide,
thereby obviating the before-mentioned manipulation.
In carrying my invention into practice I provide a developing box proper, an
auxiliary frame and an intermediate part which serves to adapt the frame upon the
said box. This part also serves as an automatic safety shutter for preventing the
access of daylight to the plate which has fallen into the box if before withdrawing
the frame I have forgotten to close the shutter with which the developing box is
provided.
The developing box is constituted by a rectangular wooden frame, into which
are inserted two sides of red glass; the space between these two glass plates

page_text: constitutes the developing chamber proper; the photographic plate is introduced
into the same through a slit, and the reagents through a funnel having a cock.
A hole is provided for the outlet of the air during the filling and a tube having a
cock serves for the emptying.
When the photographic plate is in the developing box its lateral edges engage
with grooves so that it cannot stick against the glass plates and that it will always
be bathed properly by the liquid.
As before stated I have arranged the developing box so that it can be very
easily dismounted in order to facilitate the cleaning and also the replacement of the
broken glass plates.
For this purpose the wooden frame is composed of three parts which fit together
by tongues and grooves and to receive between them in rebates the aforesaid glass
plates. In order to ensure tightness the glass plates are provided on each face with
indiarubber borders against which the edges of the parts of the frame exert a
pressure when I tighten the nuts which are screwed upon bolts traversing the
three thicknesses of the frame, and it is sufficient to remove them for completely
dismounting the developing box.
For giving strength and rigidity to the whole arrangement the outer faces of the
outer parts of the frame are covered with the sheet-metal strip upon which presses
the nut or the head of the said bolts.
One of the outer parts of the frame may have a groove into which I may
introduce a supplementary plate of red glass held in its place by a small latch.
If it is desired to remove this glass plate in order to more easily follow the
development it is sufficient to turn the latch so as to free the slit through which
the glass plate has been introduced.
The second of the two outer parts like the first may also be provided with a
groove for the reception of a second additional plate of red glass.
I provide the developing box with a shutter for obturating the slit through
which the photographic plate to be developed is introduced.
This shutter consists of a small plate of ebonite placed in the slit of the second
outer part and adapted to engage with a slit of the middle part. Small indiarubber
bands fixed with their extremities upon the second outer part of the frame and
passing through holes in the shutter plate constantly tend to pull this plate
outwards. Turned buttons hold the shutter plate in its interior position in which
it closes the aforesaid slit, but if the turn-buttons are turned the shutter plate
under the action of the indiarubber bands slide to the outside and free the slit.
At its upper part the developing box presents a guide for the reception of the
intermediate part which is caused to slide in one direction in order to put it in its
place, and is stopped in this place by a tail piece with which the said part is
provided.
A spring catch is arranged at its opposite extremity is hooked upon the frame of
the box and prevents the intermediate part from leaving as long as it is not raised
by hand.
The intermediate piece is pierced with a vertical slit which forms the prolongation
of the aforesaid slit for enabling the photographic plate to fall into the box.
This vertical slit is kept closed by a safety shutter as before stated. The said.
shutter is constituted by a small sliding plate ordinarily held by springs upon the
slit. But the shutter automatically uncovers this slit when the auxiliary frame is
put in its place by the intermediate part. For this purpose the frame is provided
with a metallic plate placed in a corresponding slit of the intermediate part.
During this movement the inclined edge of the plate encounters a pin fixed to the
shutter and by acting upon this pin pushes the obturator sideways, overcoming the
action of the before-mentioned springs so that the slit will be automatically
opened.
When the frame sliding has arrived in the position which it must occupy upon
the intermediate part is stopped by its projecting part encountering a shoulder
on the cover plate for the slit.

page_text: The frame presents a cavity for the reception of the photographic plate which
is introduced into the same through the slit which prolongs this cavity to the
outside and which is directly above the before-mentioned slits when the frame is in
its place upon the intermediate part.
The photographic plate is retained in the frame by a shutter plate which can
close the said slit; this shutter plate is carried by one side of the frame, which is
mounted by a hinge or articulated at its upper part in such a manner that its lower
part can approach or recede from the opposite side; when it is near the same the
said plate prevents the photographic plate from leaving, the first-mentioned side
being retained in this position by the engagement of a small bolt with a stop plate.
But if I raise this bolt above the stop plate, springs will push this side and the
shutter to the outside, thereby allowing the introduction of the discharge of the
photographic plate.
All the details of construction having been described I will now set forth the
mode of employing the apparatus.
The first operation to take place is to put the photographic plate in the auxiliary
frame; for this purpose the auxiliary frame being separated from the remainder
of the apparatus I raise the aforesaid bolt so as to cause the shutter to move away
sideways; then I take the photographic plate from the dark-slide and introduce
it through the said slit into the cavity of the frame; next I press upon one of the
sides in order to push it inwards, and the bolt which is submitted to the action of
a spring takes behind the stop plate so that the cavity containing the photographic
plate will be closed.
Of course this operation of charging the frame must take place so as to keep
the photographic plate protected from the light, and for this purpose it is sufficient
to effect this manipulation in a kind of sleeve of dark fabric, into which I introduce
the arms through suitable openings; the manipulation is easily effected by feeling
without the aid of the eyesight.
If it is desired to obviate this transport of the plate which has been exposed
into an auxiliary frame it is sufficient to employ the said frame as a dark-slide.
For this to be possible I replace the fixed side by a movable blind.
When the frame has been charged and closed it is taken from the sleeve and
slid into its place upon the before-mentioned intermediate part, thereby causing
the opening of the shutter; then I open the shutter by turning the button. Next
I raise the bolt in order to free the slit, whereupon the photographic plate falls
into the chamber; then the shutter is closed again, being pushed by hand inwards
while the said button is brought to a suitable position.
It will be readily understood what remains to be done in order to develop the
plate and to wash it and even to fix it if desired; the sides of non-actinic
coloured glass enable the progress of the operations to be followed without danger
of fogging.
When the apparatus is to be cleaned I remove the intermediate sliding part and
unscrew the nuts for the complete dismounting.
The apparatus may be constructed for photographic plates of large size and yet
serve for plates of small size if necessary. It is sufficient for this to introduce into
the developing box and into the frame so-called intermediaries as in the similar
instances for ordinary frames.
To this end I remove one of the outer parts of the frame from the box and
bring the right-hand lateral edge of the intermediary, which is thinned to form a
tongue, into a lateral groove in the middle part, putting a spring under tension;
when the latter subsequently expands it causes the left-hand edge of the inter-
mediary, which is likewise thin to form a tongue, to pass into the left-hand groove
of the middle part, the intermediary being thus firmly secured in the two grooves
by the pressure of the said spring.
It is then only necessary to put the outer part back in its place and to tighten
the bolts.
Of course the upper side of the intermediary presents a mortice which enables

page_text: the plate to fall into the box its edges engaging with two lateral grooves which
retain it and prevent it from being applied against the glass plates.
Holes are provided in the intermediary opposite the before-mentioned conduits
in the box for permitting the access of the liquid to the plate the outlet of the air,
and the emptying of the box.
Another intermediary may be placed in the frame in the same manner as the
first intermediary is placed in the box.
The lower side of this intermediary is pierced with a slit to allow the passage
of a plate which is retained in a suitable position for being exposed while bearing
upon the extremity of a plate spring fixed to the movable side. When the latter
moves away to the outside owing to the raising of the bolt the extremity of the
plate spring passes from below the said plate at the same time that a strip uncovers
the passage so that the plate which has been exposed can fall into the intermediary
of the box.
Although the above-described apparatus is preferably employed I do not limit
myself strictly to the details set forth; thus may construct the developing box
not only of wood but of any other appropriate material; I may moreover dispense
with the intermediate part and fasten the frame directly to the box which may
then be provided with one or both of the shutters hereinbefore described. I may
also modify the mode of tightening the frames upon the glass plates and make
other modifications of the saine kind.
It is moreover evident that my apparatus may be employed irrespective of the
process of development, and whether negatives or positives are to be developed
upon glass or any other material.
Dated this 21st day of November 1894
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.
I, EMILE POULENC, of 92 Rue Vieille du Temple, Paris, in the Republic of
France, Manufacturer, 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:-
My invention relates to apparatus for developing photographic plates.
According to my said invention I construct a portable developing box in which
photographic plates can be developed at any spot in full light.
By my improved apparatus, which is not much bulkier than an ordinary dark-
slide, I can develop and if necessary fix immediately after the exposure and in
full light and away from any dark-room.
This apparatus has the general form of a frame; it is constructed in such a
manner that the photographic plate may be easily introduced into the same
without risk of being exposed to the light, and when once in the box the said
photographic plate is perfectly visible from the outside through sides of coloured
glass, which enable the progress of development to be followed with the greatest
facility while the photographic plate is kept protected from chemical rays.
The improved box can be easily dismounted and can therefore be cleaned
interiorly in all its parts, which is an essential condition for the success of the
operations; at the same time precautions are taken for ensuring complete tightness,
although the sides of glass with which the box is provided are removable; this
removableness facilitates the cleaning and permits of the rapid replacement of
the glass plates which may break.
By suitably arranged devices the developing box can be rapidly filled and

page_text: emptied in succession with different liquids if desired, so that I may not only
effect the development and the washing of the photographic plate, but also the
fixing of the same without taking it from the developing box.
any
For the introduction of the photographic plate into the developing box I make
use of a special auxiliary frame, into which is caused to pass, after the exposure,
the photographic plate contained in the negative frame; this last operation is
effected below black cover with which the whole is surrounded, without any
necessity for passing into a dark-room. This auxiliary frame, which constitutes a
kind of intermediary gate between the dark-slide and the developing box, is
arranged so as to fit upon a removable part placed above the developing box and
forming an automatic shutter and when it is once in this position the photographic
plate may be caused by a very simple movement to drop rapidly into the
developing box.
This special frame can moreover be so arranged as to serve as a dark-slide,
thereby cbviating the before-mentioned manipulation.
In the accompanying drawings
Figure 1 is a view of the apparatus partly in elevation and partly in section.
Figure 2 is a transverse section on the line 2-2 of Figure 1.
Figure 3 is a plan view of the removable piece which is interposed between the
auxiliary frame and the developing box proper; in this figure the sole of the
auxiliary frame partly engaging with the corresponding slide of the removable
intermediate piece has been shown in dotted lines.
Figure 4 is a horizontal section of the auxiliary frame on the line 4-4 of
Figure 2.
Figure 5 is the vertical section of an analogous frame, but so arranged as to
likewise serve as a dark slide.
Figure 6 is a view, partly in elevation and partly in section, of an intermediate
device placed in the developing box for the treatment and development of plates
of a smaller size, than the maximum size for which the box is constructed.
In carrying my invention into practice I provide a developing box proper A,
an auxiliary frame B and an intermediate part C which serves to adapt the
frame B upon the said box. This part C also serves as an automatic safety
shutter for preventing the access of daylight to the plate which has fallen into
the box if before withdrawing the frame B I have forgotten to close the shutter
with which the developing box is provided.
The developing box A is constituted by a rectangular wooden frame, into which
are inserted two sides a a of red glass; the space between these two glass plates
constitutes the developing chamber proper; the photographic plate is introduced
into the same through a slot a', and the reagents through a funnel a² having a cock.
A hole a is provided for the outlet of the air during the filling and a tube a
having a cock serves for the emptying.
When the photographic plate is in the developing box its lateral edges engage
with grooves a so that it cannot stick against the glass plates a a and that it will
always be bathed properly by the liquid.
As before stated I have arranged the developing box so that it can be very
easily dismounted in order to facilitate the cleaning and also the replacement of
the broken glass plates.
For this purpose the wooden frame is composed of three parts bb¹² which fit
together by tongues and grooves and receive between them in rebates the aforesaid
glass plates a a as clearly shown in Figure 2. In order to ensure tightness the
glass plates are provided on each face with indiarubber borders a' against which
the edges of the parts of the frame exert a pressure when I tighten the nuts b³ ;
which are screwed upon bolts 6 traversing the three thicknesses of the frame,
and it is sufficient to remove them for completely dismounting the developing box.
For giving strength and rigidity to the whole arrangement the outer faces of
the outer parts 612 of the frame are covered with the sheet-metal strip 65 upon
which the nuts 63 or the heads of the said bolts 64.

page_text: One of the outer parts 61 of the frame may have a groove into which I may
introduce a supplementary plate a of red glass held in its place by a smali
latch be.
If it is desired to remove this glass plate in order to more easily follow the
development it is sufficient to turn the latch 66 so as to free the slit through which
the glass plate has been introduced.
The part like the element 61 may also be provided with a groove for the
reception of an additional plate of red glass.
I provide the developing box with a shutter for obturating the slit a¹ through
which the photographic plate to be developed is introduced.
This shutter consists of a small plate of ebonite placed in the slit of the
Small
outer part 62 and adapted to engage with a slit of the middle part b.
indiarubber bands fixed with their extremities upon the outer part 2 of the
frame and passing through holes in the shutter plate c see Figure 2, constantly
tend to pull this plate outwards. Buttons 2 hold the shutter plate c in its interior
position Figure 2 in which it closes the aforesaid slit a¹ but if the buttons are
turned into the position indicated in dotted lines Figure 1 the shutter plate
under the action of the indiarubber bands c' slide to the outside and free the slit a¹.
At its upper part the developing box has a guide d for the reception of the
intermediate part C which is caused to slide in the direction of the arrow Figure 1
in order to put it in its place, and is stopped in this place by a tail piece d' with
which the said part is provided.
C
A spring catch d² arranged at its opposite extremity is hooked upon the frame
of the box and prevents the intermediate part C from leaving as long as it is not
raised by hand.
The intermediate piece C is provided with a vertical slit e¹ which forms the
prolongation of the aforesaid slit a¹ for enabling the photographic plate to fall into
the box.
This vertical slit e¹ is kept closed by a safety shutter as before stated. The
said shutter is constituted by a small sliding plate e ordinarily held by springs e
Figure 3 upon the slit e¹. But the shutter e automatically uncovers this slit when
the auxiliary frame B is put in its place on the intermediate part C. For this
purpose the frame is provided with a metallic plate f³ placed according to the
direction of the arrow Figure 3 in a corresponding slit of the intermediate
part C. During this movement the inclined edge of the plate f³ encounters
a pin e fixed to the shutter e and by acting upon this pin pushes the obturator
sideways, overcoming the action of the before-mentioned springs so that the
slit e will be automatically opened Figure 2.
When the frame B sliding in the direction of the arrow Figure 3 has arrived in
the position which it must occupy upon the intermediate part C it is stopped by
its projecting part f' see Figure 4 encountering a shoulder e Figure 3 on the
cover plate e for the slit e³.
The frame B has a cavity y for the reception of the photographic plate which is
introduced into the same through the slit g¹ which prolongs this cavity to the
outside and which is directly above the slits e¹ and a¹ when the frame is in its
place upon the intermediate part C.
The photographic plate is retained in the frame by a shutter plate 92 which can
close the said slit g; this shutter plate is carried by one side g³ of the frame,
which is mounted by a hinge or articulated at its upper part at 9 in such a mauner
that its lower part can approach or recede from the opposite side g; when it is
near the same as in Figure 2 the said plate g2 prevents the photographic plate
from leaving, the side g³ being retained in this position by the engagement of a
small bolt 9 with a stop plate 97. But if I raise this bolt above the stop plate,
springs 98 will push this side g³ and the shutter g2 to the outside, thereby allowing
the introduction and the discharge of the photographic plate.
All the details of construction having been described I will now set forth the
mode of employing the apparatus.

page_text: The first operation to take place is to put the photographic plate in the auxiliary
frame B for this purpose the auxiliary frame being separated from the remainder
of the apparatus I raise the aforesaid bolt g so as to cause the shutter g² to move
away sideways; then I take the photographic plate from the dark-slide and
introduce it through the said slit g¹ into the cavity of the frame; next I press
upon one of the sides in order to push it inwards, and the bolt g which is
submitted to the action of a spring takes behind the stop plate g' so that the cavity g
containing the photographic plate will be closed.
Of course this operation of charging the frame B must take place so as to keep
the photographic plate protected from the light, and for this purpose it is sufficient
to effect this manipulation in a kind of sleeve of dark fabric, into which I introduce
the arms through suitable openings; the manipulation is easily effected by feeling
without the aid of the eyesight.
If it is desired to obviate this transport of the plate which has been exposed into
an auxiliary frame it is sufficient to employ the said frame B as a dark-slide. For
this to be possible I replace the fixed side g' by a movable blind as shown in.
Figure 5.
When the frame B has been charged and closed it is taken from the sleeve and
slid into its place upon the before-mentioned intermediate part C thereby causing
the opening of the shutter e; then I open the shutter by turning the buttons c²
into the position shown in dotted lines Figure 1. Next I raise the bolt in order
to free the slit, ' whereupon the photographic plate falls into the chamber; then
the shutter c is closed again, being pushed by hand inwards while the said buttons c²
are brought to the position shown in full lines in Figure 2.
C
It will be readily understood what remains to be done in order to develop the
plate and to wash it and even to fix it if desired; the sides of non-actinic
coloured glass enable the progress of the operations to be followed without danger
of fogging.
When the apparatus is to be cleaned remove the intermediate sliding part C
and unscrew the nuts 3 for the complete dismounting.
The apparatus may be constructed for photographic plates of large size and yet
serve for plates of small size if necessary. It is sufficient for this to introduce into
the developing box and into the frame B so-called intermediaries as in the similar
instances for ordinary frames.
To this end I remove one of the outer parts 62 of the frame from the box and
bring the right-hand lateral edge of the intermediary, which is thinned to form
a tongue, into a lateral groove a' in the middle part 6 putting a spring m¹ under
tension; when the latter subsequently expands it causes the left-hand edge of the
intermediary, which is likewise thin to form a tongue, to pass into the left-hand
groove a of the middle part 6 the intermediary being thus firmly secured in the
two grooves a' by the pressure of the said spring m³.
It is then only necessary to put the outer part 62 back in its place and to tighten
the bolts 63.
Of course the upper side of the intermediary M presents a mortice which
enables the plate to form into the box its edges engaging with two lateral
grooves m which retain it and prevent it from being applied against the glass
plates a.
Holes m² m³ m are provided in the intermediary opposite the before-mentioned
conduits a² a³ and a' in the box for permitting the access of the liquid to the plate,
the outlet of the air, and the emptying of the box.
In Figure 5 H is another intermediary which has been placed in the frame B in
the same manner as the first intermediary M is placed in the box.
The lower side of this intermediary H is pierced with a slit to allow the passage
of a plate K which is retained in a suitable position for being exposed while bearing
upon the extremity of a plate spring k fixed to the movable side g³. When the latter
moves away to the outside owing to the raising of the bolt go the extremity of the
plate spring passes from below the said plate K at the same time that a strip g

page_text: uncovers the passage g¹ so that the plate K which has been exposed can fall into
the intermediary M of the box.
Although the above-described apparatus is preferably employed I do not limit
myself strictly to the details set forth; thus I may construct the developing box
not only of wood but of any other appropriate material; I may moreover
dispense with the intermediate part C and fasten the frame B directly to the
box A which may then be provided with one or both of the shutters such as e
or c. I may also modify the mode of tightening the frames b¹ 2 upon the
glass plates and make other modifications of the same kind.
It is moreover evident that my apparatus may be employed irrespective of the
process of development, and whether negatives or positives are to be developed
upon glass or any other material.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is
1. An apparatus for developing photographic plates comprising a box (A) of
three detachable parts bbb2, on which a frame B, containing the negative or
positive plate to be treated, can be adapted.
2. The arrangement of grooves a' in the side walls of the developing box A ; said
grooves allowing of well washing the plate in the liquid.
3. The arrangement, in the upper part of the developing box A, of an obturator c,
operated by hand.
4. The combination with the developing box A, of an obturator e which
automatically uncovers the passage for the introduction of the plate into the
developing apparatus, when the frame B containing such plate, is put in place;
substantially as set forth.
5. The interposition, between the developing box A and the frame B, of an
intermediate piece C provided with the obturator e which opens automatically,
when the frame B is put in place.
6. The arrangement of a frame B, the movable wall y³ of which is provided with
a shutter plate 92, which retains the sensitive plate in position when the bolt g
engages behind its stop plate g and which allows the sensitive plate to drop when
the said bolt is lifted; substantially as set forth.
7. The arrangement of the wall g' of the frame B in form of a screen for
allowing the use of this frame as an adjusting or fixing frame; substantially as
set forth.
8. The adaptation, in the developing box A, of an intermediate member M;
substantially as set forth.
9. The adaptation, in the frame B, of an intermediate member H; substantially
as set forth.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.