An Appliance for Washing Photographic Plates and Prints.
Year: 1893

page_text: Date of Application, 29th June, 1893
Complete Specification Left, 27th Mar., 1894-Accepted, 5th May, 1894
PROVISIONAL SPECIFICATION.
An Appliance for Washing Photographic Plates and Prints.
WILLIAM THOMSON Professional Chemist Royal Institution Laboratory
Princess Street, Manchester England. I do hereby declare the nature of this
invention to be as follows:-
My invention consists of an appliance for washing photographic plates and prints
by a constant stream of water by which the pollution of the water surrounding
completely or nearly completely washed plates by the introduction of unwashed
ones, (as happens with the washing arrangements commonly in use at present) is
prevented.
of
My appliance is made by dividing a box made of zinc, tin, tinned copper,
pewter, or other material into separate watertight compartments or chambers by
means of sheets of the same or other material soldered or fixed water-tight along
the sides and bottom of the box. Each of these chambers is again divided by
another partition which may be fixed or soldered down the side but which must not
quite reach to the bottom of the box but is left open (by preference from to
an inch). I do not however limit myself to any special size of opening, the object
being to allow the water to flow down one side of the partition, pass under it, and
rise on the other side. The partitions which do not go to the bottom I make by
preference movable so that they can be employed for lifting the plates out of the
chamber this I accomplish by making a projection or projections from each side of
the bottom part of the movable partition upon which the photographic plates rest.
I also arrange V shaped pieces of metal or other material fixed at their apices
down each side of the chamber (which may or may not go to the bottom) four in
each chamber arranged two in each of the opposite sides of the box and on each
side of the movable partition, to act as slides for the photographic plates. It will
thus be seen that the plates may be dropped at once between the V shaped pieces
on each side of the movable partition without trouble and they may be lifted by
simply raising the movable partition which is made higher than the fixed partition
for the sake of convenience in taking hold of it.
The top of each of the fixed partitions is arranged on a lower level than the
previous one, so as to allow the water to flow from one chamber into the other in a
series of waterfalls.
The water flows from a tube (preferably fixed near the top in the back of the
appliance and attached by means of an india-rubber tube to the water-tap) down
one side of the movable partition of the first chamber, and up the other side, falling
over the first fixed partition into the second chamber and so on through all the
chambers to the last from which it is run off by a projecting tube above the level
of the last plate.
To prevent the first chamber from being deeper than the last I
arrange the
bottom to slope downwards from the former the highest partition being by preference
about an inch and a half above the last or lowest partition.
Instead of V shaped pieces separately fixed in each chamber, I claim that
crimped sides may be soldered or fixed on in such a manner that one V or crimp
will answer the purpose of a slide for the movable partition whilst the adjoining
V's on each side of the movable partition act as slides for the photographic plates.

page_text: I also claim that the two sides of the box itself may be crimped in a similar
manner to answer the purpose of the separate V shaped or crimped piece above
mentioned.
None of the partitions are higher than the sides of the box.
An Appliance for Washing Photographic Plates and Prints.
WILLIAM THOMSON Professional Chemist Royal Institution Laboratory
Manchester 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 consists of a contrivance for washing photographic plates or prints
by a constant stream of water, by which the pollution of the water surrounding
completely or nearly completely washed plates by the introduction of unwashed
ones (as happens with the washing arrangements commonly in use at present) is
prevented.
My appliance is made by dividing a box "A" made of zinc, tin, tinned copper,
pewter or other material, into separate watertight compartments or chambers by
means of sheets B. of the same or other material soldered or fixed watertight along
the sides and bottom of the box. Each of these chambers is again divided by
another partition "C" which may be fixed or soldered down the side but which
must not quite reach to the bottom of the box but left open by preference from
to an inch.
I do not however limit myself to any special size of opening, the object being to
allow the water to flow down one side of the partition, pass under it, and rise on
the other side. The partitions C which do not quite go to the bottom I make by
preference movable sliding between the V shaped pieces on either side of the
partition fixed at each side of the box or chamber, mentioned below so that they can
be employed for lifting the plates out of the chambers, this I accomplish by making
a projection or projections D from both sides of the lower edge of the movable
partition upon which the photographic plates rest. I also arrange V shaped pieces
of metal fixed at their apices down each side of the chamber which may or may
not go to the bottom, four in each chamber arranged two on each of the opposite
sides of the box and on each side of the movable partition, to act as slides for the
photographic plates. It will thus be seen that the plates may be dropped at once
between the V shaped pieces on each side of the movable partition which is made
higher than the fixed partitions for the sake of convenience in taking hold of it.
The top of each of the fixed partitions B is arranged on a lower level than the
previous one so as to allow the water to flow from one chamber to the other in a
series of waterfalls. The water may be arranged to flow by a projecting tube
tfixed near the top at the back of the appliance in communication with the first or
back chamber and attached by means of an india rubber tube to the water tap ;
or the water may be allowed to fall from the tap directly into the first chamber, or
into a projecting half-funnel F soldered to the back communicating by means of a
hole G which penetrates the back wall of the box with the first or highest chamber;
the water on entering passes down one side of the movable partition C of the first
chamber and up the other side falling over the first fixed partition B into the
second chamber and so on through all the chambers to the last from which it is
run off by a projecting tube above the level of the last plate, or through a hole or
line of holes E along the front wall of the box.
To prevent the first chamber from being deeper than the last I arrange the
bottom to slope upwards from the last or lowest chamber; the highest partition

page_text: being by preference about an inch and a half above the last or lowest partition,.
where six chambers are made in one box.
Instead of V shaped pieces I claim that crimped sides may be soldered or fixed
on in such a manner that one V or crimp on either side of a chamber will answer
the purpose of a slide for the movable partition whilst the adjoining V's on each
side of the movable partition act as slides for two photographic plates.
I also claim that the two sides of the box itself may be crimped in a similar
manner to answer the purpose of the separate V shaped or crimped pieces above
mentioned.
It is of course necessary that all the fixed partitions should be lower by about.
half an inch more or less than the sides of the box, the movable partitions however
may be higher, but for practical purposes I prefer to make them about the same
height as the box so that the whole may be covered by a lid.
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
First. The method of washing photographic plates or prints by a continuous
current of pure water in the manner herein set forth.
Secondly. In the use of the movable partition as a means of lifting the plates as
well as for directing the flow of the water.
Dated this the 24th day of March 1894.
WILLIAM THOMSON.