in washing troughs for photographic plates
Year: 1886

page_text: I, FREDERICK HAZELDINE, of Lant Street, Borough, in the County of Surrey,
Contractor, do hereby declare the nature of this Invention to be as follows:-
My Invention of improvements in washing troughs for photographic plates,
relates first to washing troughs in which an intermittent siphon is used for
drawing off the water and the improvement has for its object to arrest the action
of the siphon before the washing-trough becomes so far emptied as to uncover the
plates, as now occurs, the plates being periodically left uncovered for a considerable
length of time so that the washing action is discontinuous, and the operation is
spread over an unnecessary length of time. The siphon draws from the bottom
of the trough as usual, but in order to arrest its action when the level of the
water falls to the top of the plates, I form, in the descending or long leg of the
siphon at a height corresponding to the desired lowest level of the water one or
more apertures, capable of being closed when required, whereby air is admitted
to the siphon, and its action destroyed when the water within the trough falls to
that level.
The Invention relates further to the construction of the trough, and to the
arrangement of the plates therein. The trough or cistern contains an inner
removable frame or rack adjustable to suit plates of different sizes, in which the
plates are arranged face downward one above the other, the plates being supported
in a slightly inclined position so that they rest on their arrises, suitable fitting*
being provided to prevent the possibility of injury to the film in placing them in,
or removing them from, the trough.

page_text: Improvements in Apparatus for Washing Photographic Plates.
I FREDERICK HAZELDINE of Lant Street, Borough in the County of Surrey
Contractor, 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 of improvements in washing troughs for photographic plates
relates first to washing troughs in which an intermittent siphon is used for
drawing off the water; and the improvement has for its object to arrest the action
of the siphon before the washing trough becomes so far emptied as to uncover the
plates as now occurs. With the intermittent siphons heretofore used the plates
are periodically left uncovered for a considerable length of time so that the washing
action is discontinuous and the operation is spread over an unnecessary length of
time which it is the object of my Invention to avoid. The siphon draws from
the bottom of the trough as usual, but in order to arrest its action when the level
of the water falls to the desired point I form an air-hole in the siphon at a height
corresponding to the desired lowest level of the water, whereby air is admitted
to the siphon so as to interrupt its action when the water within the trough falls
to that level. The aperture may be closed when it is desired to empty the vessel.
The Invention relates further to the construction of the trough and to the
arrangement of the plates therein. The trough or cistern contains an inner
removable frame or rack adjustable to suit plates of different sizes in which the
plates are arranged face, or film-side downwards one above the other, the plates
being supported in a slightly inclined position so that they rest only on their
arrises, suitable fittings being provided to prevent the possibility of injury to the
film in placing them in, or removing them from, the trough.
Reference is to be had to the accompanying drawings forming part of this
specification wherein Figure 1 is a perspective view of the trough complete as in
operation. Figure 2 is a part elevation, part vertical section, of the same on
line 1-1 Figure 3; showing the water at the minimum level. Figure 3' is a
vertical section of the same on line 2-2-Figure 2, a number of plates being shown
in position therein Figure 4 is an end view of the removable plate rack seen
from the end at which the plates are inserted Figure 5 is a section of the
siphon bend drawn to an enlarged scale. The same letters of reference indicate
the same parts in all the Figures.
ii
A is the trough; B the removable plate rack or inner vessel; and C the draw
off siphon. The latter is connected with the trough A near the bottom so as to
draw off the densest portion of the washing water and the bend of the siphon rises
to a point of course just below the top of the trough. The diameter of the bore
of the pipe employed is immaterial provided it is sufficient to draw off the water
faster than it is supplied to the trough and provided it possesses sufficient capillary
attraction to ensure the filling of the bend of the siphon with water.
With a pipe
of half inch bore, or upwards, it is necessary to flatten it in the horizontal direction
at the bend of the siphon so as to reduce the distance between the top and bottom

page_text: walls of the bore to about three-sixteenths of an inch to ensure the capillary action
necessary to start the siphon automatically, when the very small supply of water
actually necessary to wash the plates is used. When the supply equals the
capacity of discharge of the siphon no flattening of the tube is necessary-but
economy of water is a very essential point.
a is the air-hole in the long leg of the siphon at a height corresponding to the
desired minimum water level in the trough It should not be nearer to the bend
than about three sixty-fourths of an inch and should be about three sixty fourths
of an inch in diameter, and for convenience of stopping it when required is
surrounded by a short tubular socket a¹ in which a cork can be inserted when it
is desired to siphon out the whole of the water from the trough.
The intermittent action of the siphon appears to be produced in the following
way; On the trough being filled, the water rising in the siphon fills the bend
displacing the whole of the air therein, and in consequence of the capillary action
of the bore at this point the siphon starts. Air is drawn in at the hole a but in
consequence of the head of water above it becomes entangled in and carried down
with the descending column of water in the long leg of the siphon. When
however the level of the water in the trough falls to about the height of the
hole a the weight of water contained in that section of the descending leg above
the air bole is no longer capable of overbalancing that contained in the rising
leg, the air then rises into the top of the bend and breaks continuity of siphon.
The removable plate rack B is in the form of a box without ends. It is pro-
vided with internally projecting ledges b, or equivalent supports at its two
opposite sides for the plates to rest on at their lower edges. It may be provided
with handles for lifting it in and out of the trough and the sides and bottom
may be perforated for the free circulation of water. Its sides are united at one
or both ends by cross-plates B¹ bridging over the upper part so as to support the
sides against the outward thrust of the plates and leave a clear opening for the
insertion of the plates at one end of the rack. The bottom and cross plates are
provided with series of grooves d for the reception of a partition plate D in
order to adapt the rack to receive plates of the various lesser standard sizes. The
plates are slid endwise into the rack, the width between the opposite sides or
between the sides and partition being such that a plate can only rest in an
inclined position between the two sides of the rack or between one side of the
rack and the intermediate partition D according to the size of the plate. Thus
supported, the lower edge of the plate rests by its arris upon a ledge b whilst
the higher edge rests, not upon ledges, but by its arris against the face of the
opposite side of the rack (in the case of the largest size plate which the rack is
constructed to receive) or against the partition D (in the case of smaller plates).
Figure 3. shows whole plates in position, and Figure 4 shows, in full lines, the
partition D in position for half, and smaller sized, plates, and, in dotted lines, in
position for quarter-plates, in which latter case the ledges at both sides of the
rack may be brought into use. The plates being supported face or film side
downwards the salts wash out therefrom much more readily than in any other
position (the washing being effectual even in still water) which is a very important
advantage.
Having now particularly described and ascertained the nature of the said
Invention, and in what manner the same is to be performed I declare that what
I claim is;-
1. In a trough, or apparatus for washing photographic plates, fitted with a self
starting draw off siphon drawing from near the bottom of the trough, the method
of producing the automatic interruption of the siphon when the level of the water
to be drawn off falls to any desired point above the inlet end of the siphon,
substantially as specified.
2. In a trough, or apparatus for washing photographic plates, fitted with a
self starting draw off siphon drawing from near the bottom of the trough, the

page_text: combination with the long leg of the siphon of the air inlet, substantially as, and
for the purpose, specified.
3. A trough for washing photographic plates provided with a removable inner
carrier frame, or rack adapted for the support of plates of various sizes in a nearly
horizontal position, the plates resting only on their arrises, substantially as
described and shown in the Drawings.
4. A washing trough in which photographic plates may be supported' film side
downwards, and upon their arrises, substantially in the manner specified.
F. HAZELDINE.
By A. M. & Wm Clark, Agents.