IMPROVEMENTS IN THE MANU- FACTURE OF SALT FROM BRINE OR OTHER SOLUTION, AND IN APPARATUS THEREFOR."
Year: 1880

page_text: LETTERS PATENT to John Howard Worthington Biggs, of Liverpool, in the
County of Lancaster, for an Invention of "IMPROVEMENTS IN THE MANU-
FACTURE OF SALT FROM BRINE OR OTHER SOLUTION, AND IN APPARATUS
THEREFOR."
PROVISIONAL SPECIFICATION left by the said John Howard Worthington
Biggs at the Office of the Commissioners of Patents on the 21st December
1880.
JOHN HOWARD WORTHINGTON BIGGS, of Liverpool, in the County of Lancaster.
"IMPROVEMENTS IN THE MANUFACTURE OF SALT FROM BRINE OR OTHER SOLUTION,
AND IN APPARATUS THErefor.'
و"
This Invention consists in further improvements on the Invention already
secured to me in Patents No. 4324, of 1876, No. 1778, of 1877, No. 2106, of 1877,
and No. 1336, of 1878.
For the production of "light salt," that is, in salt which in a dry loose state occupies
the most cubic space for its size of grain, it is very desirable to preserve the natural
angles of the crystals rather than to let them be produced with rounded corners.
Nucleus crystals formed in brine under boiling heat if again passed through
boiling brine, as is frequently the case in ordinary boiling pans, are liable to have
their minute angles redissolved or rounded off, and during their subsequent growth
appear to assume a more rounded and less angular shape than they otherwise would
do. With the view of avoiding this re-heating of the crystals, I cause a broad
current or currents of hot brine, decreasing in heat, to pass down a long pan or
pans, thereby allowing the majority of the nucleus crystals time to acquire
sufficient size to lodge on the bottom of the pan where they are fed, and grow in
their proper shape or combine with one another and form combined crystals by the
slightly cooling current passing over or amongst them.
To carry out this object I arrange various forms of pans, rectangular, circular,
ring-shaped, spiral, et cetera, and provide in all that the current passing over the
pan bottom shall cover as large an area and be even as possible. In pans where
brine has been previously circulated by the admission and outflow of brine, the
same current has not been evenly distributed over the whole bottom of the pan,

page_text: but has been drawn round sharp corners or through a narrow channel or pipe at
one end or side of the pan, resulting in a very uneven and defective action over a
large portion of the depositing area of the pan. With bottom heated pans of the
ordinary rectangular construction and with suitable pans otherwise heated, I
arrange at the opposite ends or opposite sides means of introducing or withdrawing
a broad sheet of brine which flows slowly down or across the pan, preferably over
the whole area.
For this purpose I employ perforated tubes or inverted notched
cases, troughs, divisions, et cetera, with suitable openings at the two opposite ends
or sides of the pan connecting the same by one or more pipes, troughs, or conduits
placed under, over, or by the side or end of the pan, or forming part of a pan
covered in with removable boards or plates. In some cases I employ a second
pan in place of one or more conduits for the return brine. In a less advantageous
arrangement a long division may be placed down the greater part of the pan
which I then arrange with a curved or circular end, preferably arranged with
inner curves to keep the current well spread out in both halves of the pan. I
prefer however to use a cross subdivided trough or perforated tube, and pump at
the further end of the pan for transferring the current from one half of the pan
to the other, or from one pan to another, and arrange for pricking the holes in the
pipes to prevent their being choked. The brine is caused to circulate slowly or at
any speed desired by the action of centrifugal pump, paddle wheels, screws, jets,
heat, gravity, or otherwise, preferably so arranged that a broad sheet of brine flows
over the furnaces down the pan and back by the return channel or pipe.
In this way the plates over the furnace have a less chance of collecting crystals
on their surfaces. The area of high heat extends much further down the pan than
in an ordinary pan, which may thus be advantageously lengthened with metal or
wood, and a large area of crystals lying on the bottom of the pan are subjected to
a constant evenly distributed current of fully saturated hot brine, gradually
decreasing in temperature, to assist their growth and formation. When using
deep pans I arrange so that a shallow depth of brine is first circulated, which is
increased in depth as the salt collects on the bottom of the pan. I arrange also
suitable apparatus for levelling the salt so as to maintain a more even and regular
distribution for the circulating current.
In place of using iron bottom heated pans for the deposition of crystals, I prefer
to use pans of wood preferably lined with thin sheets of iron protected from rust
by being coated with black oxide, and arrange so that the brine in its course of
circulation passes through or over heated surfaces or apparatus which I arrange for
the purpose and place in the pan, or connect therewith by pipes, troughs, conduits, or
otherwise. I prefer to heat this class of apparatus and other pans for the evaporation
of brine by high pressure steam (the waste furnace heat being preferably passed over
a surface pan) or with products of combustion reduced in temperature by the
admixture of steam or air, preferably below the fusing heat of salt, and arrange for
them to be fitted with scrapers, or preferably arranged in duplicate, so that one
half may be worked whilst the other is cleansed by a solution of caustic soda or
sal ammoniac, or other solvents, or from which the scale may be cut, planed, or
ground by revolving or edged tools, or moving stones actuated by machinery. The
heating apparatus and other ironwork in connection with them and the pans are
preferably protected from rust by being coated with black oxide by a well known
process. When using strong acid for the removal of the scale from heating surfaces
I arrange as far as possible for them, or at any rate their containing vessel, to be
made of pottery or of such material as will withstand the action of the acid. I
prefer, however, when practicable, to evaporate in the various pans and apparatus
brine from which the lime and certain other impurities have been previously
eliminated by the use of barilla, carbonate of soda, or other mineral alkalies, and
subsequent filtration or precipitation. This permits a simpler class of apparatus to
be employed, and largely recoups the cost of purifying the brine by the improved
quality of the salt produced, and the larger out put of the pans or apparatus.
When powerful brine heaters are used several pans may be worked by one

page_text: apparatus and with suitable pipes, troughs, or connections, the current may be
caused to flow along all the pans in the same direction and be brought back to the
heater by one or more pipes or conduits. Or the current may be caused to flow
down one pan or set of pans and up the next, and so on until it is returned to the
brine heater, or one pan after another may be heated up and left to cool while
another is being heated. Or with two long pans placed side by side I sometimes
place heating apparatus or surfacas at the alternate ends and pass the brine up one
pan and down the next, heating it at each end. The form of heater I prefer for
supplying several pans with hot brine is after the style of my table pan, shown
at A, in Fig. 1, of my Patent, No. 1336, of 1878.
When this apparatus is heated by furnaces and fitted with a steam dome I
sometimes pass the steam so collected, or steam from other sources, into the table
flues or into the cross flue leading to the table flues to reduce the intensity of the.
heat and increase its volume. The products of combustion and steam after passing
through the apparatus are preferably afterwards passed under an adjoining pan or
otherwise utilized. The fine salt coming from the table pan is preferably passed
with brine into this second pan or pans to acquire size. When using the apparatus
solely for heating other pans I prefer to heat the tables with steam and float
boards on the surface of the brine to prevent evaporation. I sometimes dispense
with the dome a 2 and top scraper a 13 (shown in the before mentioned
Specification), leaving the top of the pan open to a trough or evaporating vessel
and cover the pan with plates provided with openings between each pair of tables
and forcing the heated brine through from below. The bottom trough a³ and
scrapers u may also in some cases be dispensed with, provision being made to
flush out the scrapings by suitable openings in the botton or sides of the apparatus
with a continuous or occasional supply of brine from above, sometimes passing the
same through a filter. I construct a less powerful apparatus for heating brine by
using a revolving submerged heated cylinder, screw, or discs, fitted with scrapers
and deposit or flushing arrangement, in which there may be also a screw or scraper
in connection with a pocket or clevator. I sometimes also arrange tubes or other
forms of heating surfaces fitted with scrapers, also hot plates with rotary, reciprocal,
or endless scrapers, or arrange so that they may be washed or cleaned as previously
explained. Although I much prefer applying this class of heating apparatus to
pans wheroin the current of brine is arranged to flow all one way down or across
the pans, and from thence be returned to the brine heater by suitable pipes, pans,
or otherwise; outside the pan I sometimes arrange for the current to flow down
and up the same pan in one or more currents. This I effect either by the action
of pumps, paddles, jets, et cetera, or by separating the heating apparatus from
the rest of the pan by a division across the pans in which there are top and
bottom openings. With circular pans I preferably arrange a slowly rotating top
and bottom current by admitting and withdrawing the hot and cool brine from the
centre of the pan by revolving jets or otherwise. In bottom heated circular pans
I employ a disc, a disc pump, vane, screw, or combination of these to produce
the desired current. In ring pans I place the heating apparatus within or
at one side of the pan, preferably employing partial cross divisions to direct
the current, and sometimes add pockets. For bottom heated pans when the
heat applied is comparatively low, I prefer to place in the pan a metal or
wooden floor, or sometimes a combination of both, between which the return
current passes.
These two bottoms are within a short distance of one another,
and brine is forced or drawn through them, preferably at a speed exceeding
six feet per second. The brine acquiring heat in its passage is caused to flow or
pass into the pan above, where it evaporates and deposits crystals on its way down
the pan. It is then preferably passed into a settling tank, trough, or through
strainers, which I generally arrange at the side of the deposit trough, and again
passed up the double bottom to be reheated as before, returning down the upper
pan. I prefer to sink the crystals near the outflow of the brine, and place divisions
in the pan for this object, and to trap as many of the crystals as possible before

page_text: forcing the brine between the two bottoms.
I sometimes use agitators or jets of
air or brine for the same purpose. I arrange to flush the space between the two
pans. In place of using a double-bottomed pan to heat the brine I sometimes
employ numerous pipes for the same object, and preferably add deposit chambers
and scrapers. In all bottom heated pans where waste steam or low heat is used I
prefer to place them over one or more deep chambers, into which the steam or
waste heat is passed, and from which it is withdrawn or escapes by one or more
openings near the bottom of the chambers. These pans preferably have at their
edge self feeding water joints to prevent the escape of heat.
For fire heated pans
of the present or improved type I arrange to lessen the production of panscale
and smoke while economizing the percentage of fuel consumed by the following
arrangement-In the first place I employ furnaces of the best type, designed for
economy and consuming their own smoke, and preferably fitted with rocking bars
and self stoking apparatus. To protect the pan from the fierce heat thus produced
I place over the furnaces and under the salt pan a pan containing water, which as
it evaporates causes a sheet of steam to spread under the pan or along the flues
and mix with the heat coming from the furnaces. An increased volume of heat
at a reduced temperature is thus produced, and may serve for heating a much
longer pan than those generally in use. The steam and waste heat passing from under
the pan may afterwards be advantageously used under one or more pans, stoves,
or for other purposes. The water tank is fitted with self feeding apparatus. In
its place one or more perforated pipes or jets may be used to distribute steam or
air under the pan for the same object. To increase the evaparation of the brine in
open pans I arrange perforated pipes or numerous jets at the sides, ends, or else-
where in the pan (sometimes supporting the same from above), to blow air
preferably heated over the surface of the brine. In another arrangement I place
a cover, preferably of wood, over the pan at a short distance from the brine), and
cause air, preferably heated, to pass over the surface of the brine. In long pans I
sometimes arrange for the heated air and steam from the brine to escape through the
cover at intervals of its length or breadth, and place a pan above or near by to be
heated by the vapour. I supply fresh heated air by channels or perforated tubes
at the end or side of the cover or after each interval. The air for thus facilitating
evaporation may be heated by air pipes in the furnace flues or air courses in the
brickwork or otherwise, but where a surface pan is used in the same works I
prefer to heat the air in bulk by placing a wooden cover at a short distance over
a thin iron covering to the surface pan. I sometimes utilize the force of the wind
for passing air under this cover by erecting a self moving funnel or mouth facing
the wind at the top of the works, and communicating with the case or elsewhere.
Heated air from an adjoining stove, where salt or blocks are dried, may be used
with advantage, both as regards evaporation in the pan and ventilation in the
stove. To avoid the great waste of steam and products of combustion escaping
from under the covering of the deep surface pan, which may be constructed of
metal or wood rendered non combustible or otherwise, I provide one or more pans
to condense the steam and utilize the heat. Where room is of importance I mount
one of such pans at some distance over the air case, and afterwards preferably pass
the spare heat under an adjoining pan or pans by an opening near the bottom of
the steam chamber. The salt from the various pans may be withdrawn by hand,
but is preferably removed by suitable endless chain scrapers removing progressive
layers or special machinery placed on a travelling frame or carriage which moves
along or across the pan. I arrange wheels and rails at each side or end of the pan,
and sometimes also in the centre or elsewhere in the pan to lend support to the
carriage. In some arrangements I incline the rails at one end or side of the pan
to raise the carriage above its level, or arrange to transfer it from one pan to
another. The carriage is preferably made self moving after the style of a
travelling crane, but may also be caused to move by chains or ropes attached to it
and passed round or fastened to wheels or drums on one or more shafts at the ends
or sides of the pan. When the carriage is self moving I prefer to place toothed

page_text: racks by the rails on each side of the pan, into which wheels on the carriage gear.
I arrange for the machinery on the carriage to be driven by an endless rope,
revolving shaft, or by one or more engines fastened on the carriage or coupled
thereto, actuated by air, gas, or steam, with suitable receivers, boilers, et cetera, for
the supply of motive power. When driving this and other inovable machinery by
compressed air coming from a distance in a flexible tube, if the apparatus moves
in a hot place I arrange on the travelling carriage a coil to reel out the pipe into a
trough of water, by which it may be kept cool. I employ various forms of
carriages according to the work for which they are intended. In their simplest
form I mount on them one or more scrapers, which preferably can be raised or
lowered for the purpose of levelling the salt in a pan, removing successive layers
or short cuts of salt for forming the salt into ridges and for other purposes. For
producing longitudinal ridges of salt I employ a row of scrapers at an angle which
after one traverse of the carriage may either be turned or lifted to continue the
work on the back traverse. Both these forms of apparatus may be used for passing
the salt up to the side or end of the pan, or into spaces or troughs provided for its
reception, or up inclined planes above the level of the brine. In place of this
arrangement, where the carriage has to move repeatedly backwards and forwards,
I prefer (especially in long pans) to arrange for the carriage to move slowly from
one end of the pan to the other, transferring the salt in the pan during its passage.
This I effect by mounting on the carriage an endless chain of scrapers, or buckets,
which move or take up the salt in the pan and pass it to a place in the pan from
which it can be removed, or over the side or end of the pan. The pans for this
purpose should be constructed with level bottoms, but where this is not the case,
or where the bottom might be injured by the action of the scrapers or buckets, I
prefer to suspend or support the moving scrapers or buckets at a short distance
from the pan bottom by guides or otherwise. In covered pans where it is necessary
to keep the machinery low down, I preferably employ vertical wheels or drums near
each side of the pan to move the chains or links attached to the buckets or scrapers
and scrape the salt preferably into a trough at the side or elsewhere of the pan.
With open pans I prefer to place these wheels or drums horizontally and add a
third drum over the side of the pan in such wise that the salt is scraped across the
pan, passed round a drum, and drained as it travels up an incline to the third drum,
whence it is deposited onto a belt, waggon, or drawing board or chamber, from
which latter I arrange machinery to subsequently remove the salt as required. In
a less advantageous arrangement I employ only two of these wheels or druins,
generally making them of larger diameter, and pass the salt over the side of the
pan, sometimes facilitating this operation with the assistance of a movable scraper
or shoot. I sometimes attach one or more brushes to the scrapers or in place of
them. This is useful for cleaning heated surfaces and iron bottomed pans. In
place of endless scrapers or buckets I sometimes arrange one or more revolving
screws to pass the salt to the side or end of the pan or force it up an inclined plane.
For cleaning the bottom of pans, especially preparatory pans, or for cleaning
certain heating surfaces at the ends of wooden or ether pans, I arrange under the
carriage a reciprocating subdivided frame moving near the bottom of the pan or
heating surfaces. In the spaces of this frame I place stones or other grinding
surfaces, which as the frame moves rubs off the scale from the plates as the carriage
progresses. Following the stone scrapers, or sometimes in their place, I arrange one
or inore moving brushes, preferably on a reciprocating or endless chain or revolving
shaft, to sweep the loosened scale to a place from which it may be removed by
hand or by a current of brine, or water, or otherwise. For preparatory pans I
preferably provide one or more perforated pipes along the side or end of the pan,
which flush the particles into an inclined trough at the opposite end or side of the
The brushes should be made of material which is not damaged by the heat
in the pan, but where this is not practicable I arrange to lift the brush out of the
liquid during its heating by apparatus upon the carriage or by inclining the rails
at one end of the pan. In connection with or under one end of this preparatory
pan.

page_text: pan, which I prefer to heat with the waste products of combustion coming from a
stove or elsewhere, I preferably place a filter, into which the last few inches of brine
in the pan are run after the bulk of the brine has been passed into one of the
evaporating vessels. This filter is preferably arranged with an upper and lower
chamber, which communicate by a pipe and gutter under filtering material in the
lower compartment. I place floating boards in both these chambers, and arrange
to flush them, the gutter, and filter, with a copious supply of water. With a view
of utilizing very fine and dust salt from film evaporation apparatus, grinding,
et cetera, I arrange over the pan, or on a carriage moving along it, or at its side,
one or more hoppers into which the dry salt is filled, and from which it may be let
down and spread out into the pan or sieved, distributed by discs, or blown out over
the surface of the brine. For introducing fine wet salt into the pan in a scattered
condition, I preferably employ a mixing tub with revolving stirrer, into which I
pass the salt and brine which washes the particles into the pan in a distributed
state, or I place the salt in the pan and spread it out. For removing salt from the
side, end, or elsewhere in the pan, when not used for filling into moulds, I prefer to
employ a trough, into which the salt is easily passed by the apparatus, and from
which it may be removed to the end or side of the pan by suitable scrapers, or
passed over the side of the pan by a travelling elevator, belt, or otherwise. I
sometimes employ a pump and flushing trough for transferring the crystals. With
very wide pans I arrange for the salt to be moved into a trough placed in the
centre or elsewhere in the pan, and withdraw it from thence by scrapers, or raise it
on to the carriage by suitable means, and run it to the end of the carriage by travelling
belts, scrapers, or otherwise. For moving the salt along the trough to elevators or
pockets placed at the end or elsewhere in the pan, I generally employ endless or
reciprocal scrapers, or belts with occassional scrapers attached to their under
side. The scrapers I preferably arrange to move clear of the trough, except
at its two sides, where their side pieces or links are supported by little wheels or
otherwise on narrow bars or rods of hard metal or boxwood. The return scrapers
or belts may either pass in the brine to lessen evaporation, or over it, preferably
above the cover, in which case I sometimes arrange for them to dip into a water
trough, to keep them free from deposit and in working order. In pans of such
length as require two sets of trough scrapers, I either arrange for them to deliver
their salt into the pocket of a common elevator, or else arrange for them to transfer
their salt from one set of scrapers to the next, by placing the third link or belt
drum at a lower level than the second drum, or by using a short endless belt over
a pocket that can be flushed or cleaned, or I otherwise provide for passing on the
salt from one set of scrapers to the next. In very long pans three or four sets of
scrapers may be used.
In place of using elevators I sometimes employ endless scrapers or belts placed at
a low angle for raising salt from one level to another. When elevators, continuous
scrapers or belts are used for lifting salt out of brine, or in other cases where damp
salt is apt to cling to the buckets or scrapers, or belts, I arrange so that they or
their chains can be washed as they move. This I effect by suitable jets or
perforated pipes placed so as to wash off the salt into the pan or into a drain. The
salt from the pans is preferably passed through a centrifugal machine, after the
style of N, Fig. 3, Sheet 1 in my Patent, 1336/78, and the useful brine run back
into the pan. From thence I arrange for the salt to be carried by an elevator to
be dried or to a high level in a storehouse, along the upper portion of which there
are one or more endless belts or waggon ways to distribute the salt into different
parts of the store, according to quality or as required; or if this is not required, I
arrange below the spout of the elevator a distributing disc, like q2, Fig. 12 of
Sheet 3 of same Patent, to distribute the salt in the store. Along the bottom of
this store I preferably employ a travelling carriage running on rails, fitted with
scrapers or screws to advance into the salt, and pass it into waggons at the side of
the store, or on to an endless belt, preferably of tanned canvas, which discharges
into a boat, railway waggon, or other receptacle. In large or extensive works

page_text: where various pumps, elevators, and other machinery are scattered widely apart, I
prefer to drive the same by compressed air from an engine, discharging its steam
under a steam pan. The exhaust air from the various engines driving the apparatus
is used for feeding the stove, blowing salt into the pan, blowing air over the brine,
or is otherwise utilized. I arrange various combinations of the above pans, and
also pans and apparatus to bring the same into useful operation, and illustrate how
some of them may readily be adopted in the present works and others, and be best
placed for new ones. I prefer to roof in the pans by light curved or angle girders,
from the bottom of which I suspend the covers to the pans or air cases.
I arrange
to flush all pipes or portions of pans through which brine passes, where it is likely
to form incrustations. When practicable, I employ boxwood bearings and slides
for the submerged machinery. The whole of the iron work is preferably protected
from rust by being coated with black oxide, according to a well known process.
When using wood in place of iron or brickwork in hot places, I prefer to treat it
with phosphate of ammonia to render it fire proof.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, and of
an Order of the Lord Chancellor, filed by the said John Howard Worthington
Biggs in the Great Seal Patent Office on the 21st July 1881.
JOHN HOWARD WORTHINGTON BIGGS, of Liverpool, in the County of Lancaster.
"IMPROVEMENTS IN THE MANUFACTURE OF SALT FROM BRINE OR OTHER SOLUTION,
AND IN APPARATUS THEREFOR."
For the production of certain qualities of salt it is very desirable to preserve the
natural angles of the crystals rather than to let them be produced with rounded
corners. Nucleus crystals formed in brine under boiling heat if again passed
through boiling brine, as is frequently the case in ordinary boiling pans, are liable
to have their minute angles re-dissolved or rounded off, and during their subsequent
growth appear to assume a more rounded and less angular shape than they
otherwise would do. With the view of avoiding or lessening this re-heating of the
crystals I cause a broad current or currents of hot brine which decreases in beat
to pass down a long pan or pans, thereby allowing the majority of the nucleus
crystals time to acquire sufficient size to lodge on the bottom of the pan, where
they are fed and grow in their proper shape, or combine with one another and
form combined crystals by the current passing over or amongst them. To carry
out this object I arrange various forms of pans, rectangular, circular, ringshaped,
spiral, et cetera, and provide in all that the current passing over the pan bottom
shall cover as large an area and be as even and calm as possible.
With bottom heated pans of the ordinary rectangular construction, and with
suitable pans otherwise heated, I arrange at the opposite ends or opposite sides
means of introducing and withdrawing a broad sheet of brine, which flows slowly
down or across the pan, preferably over the whole area of the pan. For this
purpose I employ perforated tubes inverted notched cases, troughs, divisions,
et cetera, with suitable openings at the two opposite ends or sides of the pan,
connecting the same by one or more pipes, troughs, or conduits placed under, over,
or by the side or end of the pan, or sometimes forming part of a pan preferably
covered in with removable boards or plates. In some cases I employ a second pan
in place of one or more conduits for the return brine.
The brine is caused to circulate slowly or at any speed desired by the action of
centrifugal or other pumps, paddle wheels, screws, jets, heat, gravity, or otherwise,
and so arranged that, in furnace heated pans a broad sheet of brine flows over the
furnaces down the pan and back by one or more return channels, pipes, or pans.
With pans heated by steam or products of combustion mixed with steam, the
current preferably enters the pan at the same end as the hot vapours enter a
chamber below it.
With wooden pans the current is generally arranged to enter at the end nearest
to the brine heater. In this way the plates over the furnaces in furnace heated
pans have a less chance of collecting crystals on their surfaces and forming pan
scale. The area of high heat extends much further down these pans than in an
ordinary pan, which can thus be advantageously lengthened with metal or wood,
and a large area of crystals lying on the bottom of the pan are subjected to a
constant evenly distributed current of fully saturated hot brine, which gradually
decreases in temperature as it proceeds, and assists in their growth and
formation.
Figs. 1 to 9 illustrate various methods by which I arrange that the broad even
current is circulated up and down pans and combinations of pans of the usual
form. In Figs. 2, 7, 9, the brine flows up the pan, and is returned to the starting
point by channels or pipes. In Figs. 4 and 5 the brine flows up one pan and down

page_text: the next, back to the point from which it first started. In all the pans the current
is kept spread out (preferably the whole width of the pan) by one or more suitable
troughs, divisions, perforated pipes, inverted notched cases, see Fig. 20, or other
arrangements, by which the brine enters the pan at one end in a current extended
5 across its width, and flows to the other end where it is similarly withdrawn. By
this system of keeping the current spread out the full width of the pans at entering
and leaving, the whole area of crystals on its bottom is subjected to a far more
even treatment than when the current is circulated and drawn off at one corner
of the pan as in previous Inventions. The pans are all preferably fitted with
improved furnaces, with rocking bars, self stoking arrangements, hoppers, and tram-
ways, illustrated in Figs. 4, 5, 6, 7, and 9, after the style of Figs. 32, 33, shown
on a larger scale. The chimnies are placed in different positions, as required, to
meet the discharge of the heating gases and vapours. Fig. 1 is an end view;
Fig. 2, plan view of an ordinary pan or pans of similar size and shape, arranged
with current troughs or channels at each end, with a trough or channel at the
side of the pan connecting them together, along which the brine drawn into one
trough passes before flowing out of the other. A is a pan suitably supported from
below; B, flues heating same; C, side passages and raised ledges for draining salt
raked out of the pan; D, withdrawal trough at end of pan; E, side trough or
channel receiving brine from D, conveying it to G, the trough, by which it is again
returned to the pan at the opposite end; H is a small revolving paddle wheel
sometimes placed at the other end of the pan, with suitable arrangements to cause
brine to flow along the trough and produce the desired current in the pan. In
place of the paddle wheel a pump, screw jet, or other arrangement is sometimes
used to cause less agitation in trough G. The side trough is preferably covered
over by removable sloping lids, or I sometimes float boards on the brine in suitable
troughs to lessen evaporation. The end troughs are arranged after the style of
those described in Fig. 20, or of any convenient form suitable for the purpose in
view. The side trough is sometimes formed by placing a division in the pan or
on the outside of it, or a complete trough or pipe is placed at the side of the pan,
with connection with the pan at the two ends at d and g behind wooden or metal
divisions placed in the pan to form the sides of the end troughs, over or under
which the brine circulates. The motor is then placed in or connected with the
side trough or pipe.
Figs. 3 and 4 are end and plan views, showing the arrangement of two metal
bottomed pans A and C, with end troughs B and B connecting them. The brine
flows down the first pan and up the second back again, and so round continuously
by troughs D, D. The current in each pan being spread out, preferably the full
width of the pan, at each end by suitable troughs or otherwise, so as to cover as
large an area of the pan bottom as possible. A paddle wheel E or other motor is
placed in or connected with the trough at one end, preferably at the withdrawal
end, to cause the current through the two pans. I often employ the same arrange-
ment for pans with wooden or other bottoms where brine is run in to cool, or
where proper provision is made for keeping up the temperature in the pans by
"brine heaters" described hereafter, or otherwise. In the Drawing the pans
illustrated are metal raised over deep chambers F and H, supported by pillars and
girders, or otherwise. A is heated, preferably after the style of Figs. 32 and 33,
fitted with a steaming tank, causing a large volume of steam and hot gases to pass
under the pans to the further end, where dipping down it is drawn off by numerous
openings in a cross flue G, which transfers the vapours into H under the second
pan C, and allows them to escape by similar openings placed preferably low down
at the other end. The top of the cross flue G is preferably inclined, as shown, to
facilitate the passage of the vapours. The steam and waste heat admitted to the
further end of H impart heat to the brine above by condensation or otherwise, and
finally escape by a low cross trough at the near end, also provided with numerous
openings or a sub divided contracting channel I to the chimney J, between the end
of which and the chimney I sometimes employ an exhaust fan or other means to

page_text: keep up the requisite draught. As only the lower stratum of heated vapours are
allowed to leave the heating chambers, the upper or hotter portion remains under
the pan bottoms to communicate heat to the brine above.
To prevent the escape of hot vapours from under the sides and ends of the pans
I preferably place water troughs round the pans as described, Fig. 49. K is a high
level tramway to feed the hoppers L of the furnaces, which are preferably fitted
with self stoking arrangements and rocking bars, as illustrated, Figs. 32, 33.
Figs. 5 and 6 show a plan and sectional side view of a similar arrangement of
short metal pans lengthened by wooden or metal pans at their ends. The lettering
is the same as Figs. 3 and 4; Ax and Cx are the extensions of the pan supported:
by woodwork framing a or otherwise. The brine is circulated up and down the
pans between B and D in one pan and the opposite way in the other, as in Figs. 3, 4.
The additional length to the pans gives a largely increased area for the deposition
of crystals to be acted on by the current. Fig. 7 shows a pan similarly lengthened
by the addition of wooden or metal ends so as to provide more depositing area for
the crystals. The current however is circulated the same way in both pans,
preferably by perforated tubes T and Tx placed at the opposite ends of the pans
connected by one or more pipes t and pump or pumps P, and so arranged that
the brine is withdrawn in a broad sheet from the further or cooler end of the
pan at Tx and is again returned to it at T over the furnaces or hot flues in the
same fashion. The pumps are preferably fitted with small engines and driven
by steam or air. The hot gases and vapours from the end of the chamber under
pan A are withdrawn by a cross flue G and brought back to the near end of the
chamber under pan C by the dotted flue Gx, preferably placed between the
supporting walls of the pan on each side. Gx discharges is vapours by a cross
flue similar to G at G, L, and the vapours pass under the bottom of C untill reaching
a low cross trough I of the same type communicating with the chimney J or
otherwise. The pan A is preferably similarly fitted with a tramway and hoppers,
self stoking furnaces, rocking bars, and steaming tank, et cetera, as previously
described in the foregoing Figures. Figs. 8 and 9 give an end and plan view of
a metal pan A 1 and wooden pan C1 placed side by side, affording a very large
area for the deposition of crystals, both heated by the furnaces under the metal
pan A 1.
Al is preferably similarly heated to that in Fig. 32. When using pans
made of wood I prefer to protect their bottoms from the action of rakes or scrapers
by covering them with thin sheet iron coated with black oxide to render it less
liable to rust.
The vapours from the further end are conveyed by a long flue G 1, 2, under the
central passage between the pans to chimney J at its end. Above this flue there
is a metal bottomed trough H, down which the return brine from the troughs of
both or either pans is caused to flow by paddle wheels h and hx placed at either
end of H. They withdraw the brine from both pans by the end cross troughs d
and dx, and returning it to them again at the other end by troughs i and ix. The
admixture of brine in the central trough causes the wooden pan C1 to be heated.
In some cases I circulate the brine in pan A separately by end troughs or pipes or
otherwise, and use the trough H solely for heating pan C1. In place of this
arrangement the current from Al to C1 may be transferred as in pans A and C,
Fig. 4, causing the brine to flow opposite ways in the two pans when the waste
gases from under A 1 are drawn off by flues to a chimney preferably placed at Jx
behind the further end of the pan.
The object in arranging for the current of brine to flow in the same direction in
parallel pans is that the salt produced in them then accumulates more at the same
ends of the pans which facilitates its removal to a common store room.
The salt produced in long pans is preferably removed by machinery hereafter
described, suitable rails being provided at the sides of the pan for its application.
By using machinery to remove the salt from the pans they can be placed much
nearer together. When removing it by hand I provide the ordinary space between
the pans and elsewhere.

page_text: Fig. 10, plan view, is an arrangement of 4 pans, two long metal ones A and B,
and two wood C and Cx. A is the pan under which there are furnaces D and
steaming tank E, as previously explained. The steam and hot gases are circulated
by flues & under each half of the pan, as indicated by the course of the flues d
or otherwise, but preferably so as to yield the greatest heat under the front half
of the pan parallel with the rails E, while the steam and gases at a reduced
temperature pass under pan B and find their way to chimney F at its end. Pans C
and Cx are preferably of wood placed on the same level as the other pans. C, B,
and Cx all communicate with pan A at their ends and its side, providing a free
course for the brine to pass over the width of A and the length of the other pans.
To produce a circulation of brine of this description I preferably employ perforated
tubes g 1, g 2, and g 3, at the end of pans C, B, and Cx, and a long perforated tube J
extending along the side of pan A from j to jx. The former and latter pipes are
connected by pipes i1, 2, 3, or otherwise, pumps h1, h2, h3, being provided
in the circuit to pass the brine from g 1, g 2, and g 3, to the pipe j to maintain the
circulation of brine in the pans. I sometimes arrange for the brine in whole or in
part coming from pan B to be passed down C and Cx, the brine from C and Cx to
be passed in whole or part down B by altering the direction of pipes i1, 2, 3.
The salt in the pans is preferably manipulated by travelling carriages L1, 2, 3,
and M, arranged to pass over them running on rails 11, 12, 13, 14, m1, and m 2.
I prefer to place all the rails above the pans, and rail m 1, which crosses the ends
of C, B, and Cx, is supported at intervals from beneath so as to interfere with the
current as little as possible. The arrangement and working of the carriages is
described later on. L1, 2, 3, are arranged to draw the salt from the pan and pass
it either over the sides of the pan into a store or wagons running along passages N
or so as to fill belts or other vehicles to transfer the salt to where it is wanted;
carriage M is more especially provided with rubbing stones after the style of
Fig. 150, to keep the bottom of pan A free from incrustations. It preferably carries
a small pump mx and divisions at the side of the rubbing stones to form a trough
fastened to the carriage which enables the rubbings to be flushed over the salt in
the other pans, where they can no longer combine with the metal bottom over the
bot flues and so hinder evaporation. In some cases I raise or incline the bottom
of A to facilitate its being cleaned or to quicken the flow of brine across A and so
lessen the deposition of crystals on its bottom. Occasionally I raise the bottom
of this pan to within a few inches of the surface of the brine in C, B, Cx, and
place a division in the pan under the rail m 1, over which the brine is caused to
flow from a higher level than that in the other pans; a second division or sloping
ledge is arranged behind this, under or over which the brine so poured finds its
way to the pan after the style of Ax in Fig. 48, or with divisions D and B, as in
Fig. 43. The object of this arrangement is to enable pan A to be drained and well
cleaned without emptying the pans C, D, Cx, which may be left to continue their
evaporation slowly whilst the operation is completed and the pan refilled and the
heating re-commenced. The way in which I prefer to clean the pan under such
circumstances is described under Figs. 150-2.
With the view of getting a long uninterrupted flow of brine, and also to facilitate
salt from a very extensive area of pan being easily removed with one pair of pan
carriages hereafter described, I arrange two pans B and H, Fig. 11, side by side,
with arrangements for heating the brine twice or more in its circuit as it flows up
one and down the other. I prefer to place them a little above the ground, and
arrange side rails and other appliances for receiving and removing the salt delivered
by the pan carriages.
They are preferably of wood, suitably supported from below, and heated at the
opposite or alternate ends. The brine passes up one pan and down the other, being
transferred from the cool end of one pan to an adjoining brine heater, where it is
heated up and sent down the next pan to be heated in the same way at the other
end, and passed back again, and so on. A is a brine heater hereafter described
supplying heated brine to pan B, which flows down it to a trough or perforated

page_text: pipe c, c, from which it is passed by pipe d to pump e, thence by pipe F to the
second brine heater G, which supplies heated brine to pan H.
The brine in H flows down to a second perforated tube or trough i, i, from which
it is passed by pipe j to pump K, thence by pipe to the brine heater A, when the
brine is again heated up and continues the circuit.
The class of brine heater preferred for this arrangement is shown Fig. 57 and
Fig. 63. Ax and Gx are the boilers, a and g the pipes for supplying steam to their
respective brine heaters A and G. The waste surface of gasses from the boiler
furnaces are preferably passed over one or more surface pans, and subsequently
under pans heated by their steam and gasses. The salt from the pans is best with-
drawn by travelling pan carriages, such as are hereafter described, which fill waggons
moving on rails between the two pans in a sunken roadway M.
The waggons are preferably moved by a wire rope, and the pan carriages are
preferably fitted with engines and boilers or gas receivers to enable them to move
alternately from end to end of the long pans each time they are started. I some-
times lay out works with two or more complete pairs of these pans and beaters
side by side, so as to use more powerful boilers at the two ends and economise
labour. I prefer to have two up current pans to one heater, and two down current
pans for the other, so that the salt collecting in each pair may drift to the same
ends of the pans and be more conveniently removed by coupled pan carriages. The
salt is then generally conveyed in troughs or on belts, and collected at one or more
places along the sides of the pans, from which it is conveyed by waggons or other-
wise along cross passages under the pans to a loading quay, storehouse, et cetera, at
their side. I adopt various forms of brine heaters or means for heating up the
brine at the alternate ends of the two pans, arranging them according to the size
and length of the pans to be heated. I preferably arrange four or eight or twelve
long parallel pans with the current passing from end to end of each pair in the same
level, and to which it is passed as previously explained. The brine is heated on
its passage to the alternate ends of each pair untill it reaches the end of last pan,
where it is sent back again to the first pan where it first started. In some cases I
work each double pair of four pans separately so as to better equalise the rate of
current in the various pans. Occasionally I heat the pans by furnaces or steam
under their bottoms in place of using brine heaters. When so doing a portion or
all of each pan or pair of pans is made of metal for the hot gases to pass under for
heating the brine.
Fig. 12 is a plan view of another arrangement of works, wherein the brine is
circulated successively through four pans, up one and down the next, and so on untill
it is returned to the brine heaters for reheating a fresh circuit. This system of
circulation is best adapted to cases when different degrees heat are required in
different pans.
A is a brine heater, preferably of the type shown in Fig. 57. It
supplies heated brine to pan B, down which the brine passes, and is transferred to
pan D by a series of curved troughs C. The brine in D is transferred by similar
troughs E to F, which again passes round the curves G and down pan H, to be
returned to the brine heater for continued circulation by a perforated tube or
trough I by pipe j, pump K, and pipe . The subdivisions in the curved ends are
arranged so as to keep the current in each pan well spread out over the bottom of
the pans. To facilitate this in front of each curve there is a division or partial
division b, d, f, h. The brine passes over b and f and back by suitable openings at
the bottom of d and h. M are preferably tube boilers occupying little space for
supplying steam to the brine heater by pipe m. The waste heat from the boiler
furnaces passes over both or either half of a surface pan N1 and N2 to the
chimney O, sometimes in its course to the chimney also passing under a bottom
heated pan.
An air case is preferably arranged over N1 and N 2 as hereafter
described to heat air for perforated tubes placed at the sides of the pans, and through
which it is preferably blown by fans or otherwise.
I prefer to withdraw the salt from the four current pans by travelling pan
carriages, which empty it into waggons or belts running in passages p¹ and p². O is

page_text: a storehouse for the salt from the current pans, and R the place from which the
surface pans are emptied by suitable water tight doors. At the end of the pans S
is a passage for waggons containing salt from Ň 1 and N 2 to be passed to the front.
T is the boiler house.
Figs. 13 and 14 are the plan and side view of an arrangement of works with
four pans supplied with one large brine heater of the type shown, Figs. 59-60,
with boiler, side pans, and store rooms. A 1, A2, A3, A4, are preferably long wooden
pans, in which the current runs the same way between the perforated pipes B at
one end and the troughs C at the other; D is a common trough drawing the brine
from the cross troughs of all four pans. It supplies the pump E, which forces
the cool brine through the brine heater F into trough f, supplying the cistern
hoppers F1 and F 2. The scrapings from the pan are brought up by elevator fx.
F1 supplies brine by pipes g 1 and g 2 to the perforated pipes B in pans A1 and
A 2. F2 supplies heated brine by pipes g3 and g 4 to the perforated pipes B in
pans A 3 and A 4.
With this system of pipes and suitable arrangements at the
other end of the pans each pair of pans, or each pan in succession, may be heated to
a high temperature, and left to cool while the next one or pair is similarly treated.
Hare the boilers for supplying steam to the brine heater F by pipe h; II and I 2,
surface pans to use up the waste heat from the boiler furnaces and heat air in cases
J1 and J 2, which is blown over the pans by suitable fans or engines and perforated
pipes placed along the side of the pans. Above the air cases are preferably pans L,
covered with air cases Lx, and supplied with hot air, as hereafter explained. The
steam and waste heat coming from under the cover of the surface pans escapes into
chambers K, and is used for heating these pans; M1 and M 2 are chimnies into
which the spent gases find their way by low openings in the bottom of chamber K.
To improve the draft I sometimes employ fans to pass the hot gases over the
surface pans, or exhaust the cool ones and pass them up the chimnies; N 1 and N 2
are store rooms, into which the salt from the pans is delivered. The salt from the
pans is preferably passed into these rooms by coupled pan carriages described here-
after, each working a pair of pans, and supplying one or more endless belts placed
along the passages 01 and 02. I sometimes employ centrifugal draining machines,
after the style of N, Fig. 3, of my previous Patent, No. 1336, of 1878, to drain the
salt fed by the belts, and run or pump the brine back again into the pans, both
here and elsewhere. The salt from the deep surface pans I and Ix is withdrawn
through watertight door at their ends or sides, and duplicate pans are provided so
that there may be but little waste of heat while one of the pans is being emptied.
If only a slow current is required in the pans A, I sometimes lower the brine
heater so as to economise the power required for pumping the brine through it.
Passages are left round the pans, and the works are provided with suitable walls
and covering.
With the view of applying the foregoing system of broad current circulation in
the pans from the furnace to the cooler end to round pans which have received
some attention for the removal of scale by mechanical means, I arrange to combine
with these round pans in which the brine is economically heated long current pans,
in which the crystals can form in their proper shape and acquire size by the hot
fully saturated current of brine passing over them. This result is particularly
desirable in connection with those round pans at present producing "patent butter
salt," a class of salt that is considered "heavy," or which occupies less cubic measure-
ment for its weight than salt produced in the ordinary rectangular pans. I illustrate
in Figures 15, 16, 17, a plan view of the upper floor, ground floor, and sectional
end view of a combination of pans in which this arrangement is carried out, where
the steam from the boiling brine is equally utilised, while the waste heat coming
from the furnaces produces an extra quantity of salt. A, A, serve to illustrate
duplicate round pans of the ordinary type placed over furnaces, and partially freed
from scale by rotating scrapers of various construction. The scrapers are generally
turned by a central shaft, bevel wheel, and cross shaft, and by an engine and boiler,
which latter are frequently placed between the pans. The salt is past by the

page_text: scrapers into side pockets, from which it is frequently removed by manual labour.
The waste steam and smoke is sometimes utilised by passing them under steam and
smoke pans at the back of the round pans. In applying my improvements to this
style of arrangement I connect the front and back pans so that a broad current of
brine may be passed down both from the extreme end of one to that of the other.
I preferably place perforated pipes or troughs a, a, in front of each of the round
pans, and force a current of brine over their bottoms. On the opposite side of the
round pans I arrange a partial division b, b, under, over, or through which the brine
flows into the second pans B. There is, preferably, a second partial division
bx, bx, which spreads the current out the full width of the pan B. The heated
brine thus flowing into B (which may be of any suitable length) forms and deposits
crystals as it travels to the further end, where it is withdrawn from across the
whole width of the pan, preferably as shown, Figure 80, and passed back again to
the front of the round pan for a similar course of circulation by the pipes c, pumps e,
and pipes cx.
In this manner a continuous circulation of brine is kept up, and
the brine heated in the round pans passes into the long pans before it has had time
to deposit many crystals on the bottoms of the former. To reduce the chance of
this I preferably employ floating boards over the brine in the round pans and
between the division. The waste heat from the furnaces may be passed under the
bottoms of pans B, but is preferably otherwise utilised. I prefer to construct the
pans B of wood or metal and wood, and raise the metal pans which formerly
occupied their position to a higher level, as shown at I, I, or place them elsewhere
to be heated by steam or otherwise, or use new metal pans with metal bottoms for
the purpose. The furnace gases, and also those from the boiler are preferably passed
over the surface of the brine in a deep central surface pan. It is divided into
two parts D1 and D 2, so that the salt from either part may be withdrawn through
water tight doors at its further end, while the furnace gases are passed over the
brine in the other. Suitable flues & and dampers at each end being provided for
the purpose, as in the pan described in my previous Patent, No. 1336, of 1878.
Over these pans I place a thin metal covering, and above this arrange a case E
for heating air in either half after the style of Fig. 82. The air is admitted to the
further end of the case E by suitable valves, so that either half of it may be worked
at one time, and withdrawn by a perforated pipe or channel e placed across the
near end of the case, and connected with an exhaust fan F which blows the heated
air it receives down pipe f, cross channel fx, and under cover G placed over the
pans B to assist evaporation. The heated air and steam from the pans B escape
from under the cases at their other ends g, and rise in the chamber H under the
pans I. It is drawn along the bottom of these pans, from which I sometimes hang
pendant partial divisions, as illustrated, Fig. 82, and finally escapes to the chimney
by the flues placed across the ends of the chambers, and preferably arranged low
down. Any steam rising from the round pans is conducted by suitable pipes, as is
also that from the engine into the chambers H. The cases placed over the pans are
preferably arranged with sloping tops to drain of any condensed water falling on
their surfaces into gutters arranged along their sides, or elsewhere. The heated
gases and steam from the surface pans B1 and B2 enter the chamber K at ex,
and rise under the pan L. The vapour from K (may also pass under pendent
partial cross division, as in H), and is either drawn off to chimney M by a low
cross trough placed at the end of the chamber, or passed into the adjoining side
chambers H to assist in heating the pans above them, and so on to chimney J.
The brine in the upper pans is preferably circulated by troughs and paddles, pipes,
pumps, or otherwise down the central pan L from to lx in a broad sheet, and
afterwards passed up the two side pans I in a similar way, back again down L,
and so on.
I sometimes cover in the upper pans with cases for hot air, but
preferably employ in their place perforated air tubes arranged on each side of
the pans, and blow hot air from the case E over the brine in the pans to assist
evaporation. I prefer to use purified brine in these upper pans, and in all other
bottom heated steam pans, or pans heated by gases or vapour at a low temperature,

page_text: the object being to facilitate the heat rising from the bottom of the pan when a low
heat is used.
The employment of purified or partially purified brine is a matter of much
importance where steam, products of combustion with steam, mixed, or other low
heat is the medium for causing evaporation in the pan above. Ordinary brine
contains many impurities, notably lime, which forms a hard scale on steam heating
surfaces, and in time render their efficiency almost useless. When this occurs the
pans have to be drained to permit the scale to be chipped or ground off by
manual labour. By employing purified brine from which the impurities have been
eliminated, I avoid this lime scale forming on the plates or other heating surfaces,
and keep them in a state of far greater efficiency.
Whenever pans are placed over deep chambers, like H or K, I prefer to admit
and to withdraw the heating gases or vapours from as near the bottom of the
chambers as possible, so as only to permit the lower stratum of heat to be with-
drawn, thereby keeping the greatest amount of heat close to the pan bottom above.
To avoid the escape of hot vapour or gases from under the sides or ends of the pan,
I preferably arrange water-joints round the top of the chambers, as hereafter
described. I sometimes arrange foot passages around the pans so that they may
have their salt withdrawn by hand. In the Drawing I have shown them scraped
by travelling pan carriages, after the style of those illustrated in Figs. 80, 81.
I arrange tramways N and O, and provide for the removal of the salt from the
ends of the pans. The salt from the two upper pans I is delivered into waggons
on N, and that from I to waggons on O, or otherwise. When separate currents for
each pan are used, all their salt is preferably delivered at one end of the works.
The pumps and machinery are either driven by steam, or compressed air, or other
suitable means. The building is made strong enough to support the upper pans
with girders and pillars, and the whole is suitably roofed in and lighted. In some
cases, where space permits, I dispense with the upper story, and arrange the pans
I, I, I, at the ends or sides of B, D, B, with suitable connections between for the
steam and gases to pass; and in other cases I only employ the pans of the lower
floor, and allow the steam and waste heat to pass into the air or chimney. When
laying out new works, where the fire heated ends of the pan B, B, are scraped by
rotating, or reciprocal, or other varieties of mechanical scrapers, I prefer to lengthen
the upper pan I so as to cover the furnace ends of the lower pan, thereby giving
more depositing area for the crystals in the pan above. When employing recipro-
cating frames of scrapers or rubbing stones in place of the rotating scrapers, the
divisions b and bx may sometimes be dispensed with, and a broad even current be
sent from one end of the pan to the other without meeting with any surface
obstruction, excepting such as may be necessary for moving the frames of scrapers
or stones. When using rectangular plans on this system, I arrange to admit and
withdraw the current of brine across the whole width of the pan, as previously
explained.
Figs. 18, 19, plan and side view of certain improvements applicable to boiling
pans and stoves of the ordinary description, to illustrate which an outline of a
small plant of four pans and accompanying stovehouse, to which the improvements
are added, is shewn in dotted lines. A, the boiling pans; B, the stovehouse,
shewing arrangements of furnaces a, flues b, chimneys c, et cetera. The details of
adaptation must necessarily vary in accordance with the general arrangement of
works to which the improvements are applied. The improvements illustrated
consist, first, in supplying the pans with periodical charges of hot brinc, from
which the carbonate of lime and certain other impurities have been previously
eliminated in a pan specially arranged for self cleaning, and heated by wasto
furnace gases or otherwise; second, the ventilation of stoves by withdrawing their
vitiated air, and using it to improve evaporation by blowing or passing it over the
surface of the hot brine; third, the employment of broad circulating currents of
brine from the furnace end of the pan to keep the plates over the furnaces more

page_text: free from the deposition of crystals, which are at present liable to get burnt on to
the plates, and cause frequent stoppages and injury to the pan.
In the first place I arrange to partially. purify the brine to be evaporated in A,
employing preferably a long narrow pan D for the purpose, placed behind the
stove B, where it can be heated by the waste gases generally allowed to escape
from the chimney C. It may however be placed at the side of the pans or
elsewhere in close connection with them, and in some cases I use seperate furnaces
for it. The pan is mounted on walls d with water joints, and preferably arranged
with self-stoking furnaces, and passages round the outer sides and ends. E is the
chamber enclosed within the walls d, into which the hot gases coming from the
pans or stove house are passed by an extension of the flues b past the chimney
to b1, and the introduction of a flue 62 or otherwise. There is a swinging
valve 63 which, when placed in the position shewn, passes the gases into the
chamber at 61, from which they rise under the pan, and afterwards escape to the
chimney by 62. When the valve is turned up it closes the flue leading to bl
and 62, and allows the gases from the stove flues to pass direct up the chimney.
By this means or the use of suitable dampers, et cetera, the heating or cooling of
the pan is easily controlled. The pan is made with an even bottom, the plates of
which it is composed being arranged with suitable joints or flat bars of metal on
the under side, to which both plates are riveted, with level heads on the upper
side. On one side of the pan there is a gutter d, d, by which the pan may be
drained, under control of a valve and handle dx; on the other a long perforated
pipe d2 to cause a flow of water over the pan bottom to the long side gutter d, d,
under control of the valve and handle d1. At this end of the pan I preferably
employ a filter, see Figs. 21 and 22. Dx is a travelling pan carriage, after the style
of Figs. 150, 151, and 152, fitted with reciprocal rubbing stones, and preferably a
revolving brush. It moves along rails e, ex, at the sides of the pan, and is some-
times arranged to pass up an incline to lift the stones and brush out of the liquid.
It is preferably driven by an endless wire rope ƒ stretched between the wheels ƒ 1
and 2, and suitably driven.
This pan is connected with the boiling pans by valves and pipes g and gx or
otherwise. The size and capacity of the pan is preferably equal to one charge of
liquid for the pans A; it is filled with brine from the brine head or otherwise by
turning handle d3. The heat is passed under the pan into chamber E. The brine
in the pan rises in temperature when the scum is removed with the use of glue or
otherwise. When the pan boils the carbonate of lime and certain other impurities
in the brine are percipitated to the bottom of the pan, and are afterwards removed.
These impurities generally find their way into the boiling pans, resulting in injury
to their plates, reduction of evaporative power, and frequent stoppages for their
removal. When the percipitation of carbonate of lime, et cetera, has taken place
the heat is shut off from the chamber E below, and the pan is quickly emptied by
pipes or conduits g, gx, which are preferably of large diameter, into the pans A.
They are thus supplied with far purer brine than they usually get, and at a high
temperature ready for continuing the process of evaporation. The pan D is raised
sufficiently above the pans A to facilitate the emptying process being carried on
quickly, the object being as far as possible to prevent the deposition of salt on its
bottom, which would result if all the surplus water in the brine were evaporated
off before the hot brine was transferred to the other pans.
The last inch or few inches of brine in the pan are preferably passed through a
filter at the end of the pan, like Figs. 21 and 22, to strain out impurities, which
might otherwise find their way into the pans A. The valves gx are closed; the
pan is thoroughly washed out by turning on water by pipe d 2, the drainings
being conducted away by the gutter d into a drain or otherwise. The pan
carriage Dx is started traversing from end to end of the pan and back again, and
the bottom is well rubbed with stones to remove the scale collected thereon, and
the rubbings brushed and washed away to the gutter d into a drain. When the

page_text: carriage has done its work it either runs up an incline to lift the brush above
the pan or the latter is raised. The pan is again filled with brine and a fresh
supply again prepared for another charge for the boiling pans, and so on. I some-
times slope the pans slightly from one end to the other, and admit the washing
water by a perforated trough at the higher end. In this case the side gutter d and
the side pipe d2 may be dispensed with; I sometimes arrange a narrow pan of
the above type along the ends of a long line of pans, and arrange it to hold
sufficient brine to feed them in sets progressively or otherwise. In combination
with this system of heating brine for other pans, and afterwards washing out and
mechanically rubbing off the impurities deposited by such treatment, I sometimes
employ circular or other shaped pans with suitable pipes and connections, in which
are arranged one or more stones, preferably sets of stones, in suitable frames
actuated by power and made to rub the bottom of the pan, preferably by revolving
arms or reciprocating frames. I arrange small scaling pans of this type for feeding
single pans or small sets of pans. E is a long perforated pipe or channel placed
along the back of a stove, and preferably set low, aud connected under or over the
entrances to draw off vitiated air from within, fresh air being admitted elsewhere
by suitable openings. A pipe connects E with a fan F which blows the hot air
withdrawn from the stove down pipe g to a cross pipe Fx extending along the ends
of the pans. This pipe is connected with perforated pipes f placed at the sides of
the pans and supplies them with a current of warm air to blow over the brine in
the pans, and assist evaporation. H are pumps for circulating brine in the pans by
perforated pipes h and hx, as previously explained, to lessen the deposition of
crystals on the hot plates over the furnaces. They are driven by belts or otherwise
from a cross shaft I, or by steam or compressed air, by which latter means also the
other machinery in the works is sometimes driven, or one engine may drive the
whole with suitable shafts, belt gearing, etcetera. J is a door from the stove to the
fan room; j, a staircase to platform Jx for getting round the pan D which is covered
in by a light roof.
Fig. 20 is an is an illustrative group of different varieties of troughs, et cetra,
Buch as I preferably employ for admitting or withdrawing brine to or from a pan,
also instruments for keeping the same in working order. The end portions of the
pans where they are employed are shown in section and on an enlarged scale.
A is an end view of a trough arranged in a pan of ordinary or improved
construction, a a division placed across the pan end forming the trough ax,
from which the brine is withdrawn by suitable pipes or openings. The division a
is raised a short distance from the bottom and supported by curved metal stands a 1,
at its back, so that an instrument a 2, may be passed under the division for
removing any accumulation of salt that there may be under it, causing an uneven
withdrawal of brine and a consequent disturbance of the current in the pan.
B is a sectional view of a pan with a trough bx. In this case the brine flows
over the top of the division b, which is preferably made with an undulating top
(see Bx side view) easily kept clean by a forked slide b 2 at the end of the handle,
which pivots on the top of the slide and draws or pushes it backwards or forwards.
In some cases I make the top of a division level, or arrange a row of holes below
the surface of the brine, or provide a submerged opening or slit a little below the
level of the brine after the style of the space at the bottom of a by suitable curved
supports at the back of the division connecting an upper and lower part, and
permitting an instrument like a 2 to be passed along the slit to free it from
incrustation.
C shows a sectional end of a pan fitted with a submerged perforated pipe c with
the holes facing outwards, it is supported by brackets cx from the end of the pan. An
instrument c 2 is arranged with a bar which extends along the pipe for a few feet with
a hook and rest c3 at each end to rest on the pipe and clasp it when the instrument
is drawn backwards. Along the bar there is a row of steel points, cach fitting and
pricking a hole in the perforated pipe to keep the holes open.
D shows a sectional end view of a similar perforated pipe d and Dx, an

page_text: instrument fitted with a wheel dx (see side view D) provided with short steel
projections to prick slits or holes in the tube as the wheel is passed along it. The
wheel is protected by a case on the outside, and is carried by bearings on the
bar d 1, at the two ends of which there are curved scrapers d 2 to steady the
wheel and scrape the pipe; d3 is a rest for the instrument, serviceable for adjusting
the points in the holes at starting; d4, a handle by which to move the instrument
along the pipe. I employ the same style of instrument for pipes with their holes
set upwards or downwards, arranging the brackets which support the pipes and
the handles for moving the instruments to suit the position of the holes. In some
cases I connect the perforated pipes with a boiler or pressure of water or brine to
force the holes open by pressure from within. The holes in this case are slightly
tapered, so that loose crystals may be blown out of them.
E shews a sectional end view of a pan fitted with an inverted notched case e,
made in one or more lengths, and placed along the end of a pan. Ex is a sido view
of the case; the case or lengths of it are arranged to draw up and down by
chains el passing over pulleys, and attached to weights to counterbalance the
weight of the case. When the case is down the brine passes under its notched
edge e 2 and is withdrawn by pipes e 3, keeping the current well spread out. The
case can be at any time raised wholly or in parts, and any salt drawn in by the
current and collected on the bottom be removed from underneath. Notched cases:
of this description have sometimes been used for bubbling air into pans containing
chemical solutions, but not in the way described, or for admitting or withdrawing
currents of brine.
Figs. 21 and 22 show the arrangement of a filter more especially designed for
working in connection with the scaling pan D, Fig. 18, but which I sometimes
employ for the purposes. A, the end of scaling pan; Ax, side trough; B, wall
supporting pan; C, water joint to retain heat; D and Dx, top and bottom parts of
filter E, long strainer; F, trough under same, with valve Fx governed by
handle and rod fx; G, drain; I, pipe from the pan trough Ax to D and G,
governed by handles d and g; rods d¹ and g', and valves dx and gx; J, pipe from
D to F; K and Kx, perforated flushing pipes; L and Lx, floating boards.
The last few inches of brine in the scaling pan A, as also the flushings from other
pans, are run into D by pipe I. It empties itself down J through the strainer E
into Dx, from which it is afterwards pumped back into A. When Dx is empty
valve Fx is opened, and the bottoms of D and Dx are washed by a copious supply
of water from K and K×. The drain G is flushed by opening gx, when the pan A
is being washed out during the rubbing process.
Figs. 23 and 24, side and plan view of one of a pair of ring pans with an inner
circular pan, in both of which are circulating currents of brine, and from both of
which the salt is preferably withdrawn by machinery; A is the ring pan,
preferably made of wood, and suitably supported from below; a, a, the walls
surrounding it supporting the roof and a rack and rail at ax round the pan for the
pan carriage B, as hereafter explained, see Figs. 112 to 136; C is the brine heater
which heats the brine in the pan and produces the desired current by withdrawing
cool brine at c, the width of the heater, and returning it heated at cx, also the
width of the heater c1 is a moveable division in the pan which is balanced and
draws up and down. It is raised to let the pan carriage pass on its circuit and
lowered again after it has passed by. D is an elevator passing any salt received
in c to E, a centrifugal machine after the style of N, Fig. 3, of Patent No. 1336, of
1878. It delivers the salt after freeing it from it surplus brine by elevator e,
which feeds an overhead endless belt f, which in its turn feeds a second endless
belt which is made to move either way and arranged to deliver the salt to any
part of the store H, over which it travels after the style of 3, in Figure 172. I is
the inner wall of the building supporting the roof by pillars, also the other end of
the pan carriage by a rail and racks similar to the one on the other side, also a
rail and rack on the other side of the pillar for the scraper arm P of the circular
pan. The pan carriage travels round the ring pan on the rails on either side and

page_text: is provided with suitable sized wheels at each end to keep the carriage in a true
line with the centre of the ring. It is preferably driven with an engine and boiler
carried on the carriage or by compressed air or gas carried in receivers, also
mounted on the carriage, or by flexible tubes connected with it at different places
and supplied with high pressure air from a pipe encircling I, into which the air is
forced by suitable air compressors. In some cases I arrange a drum or coil under
the carriage to pay out the air tube as it progresses, or drag a tube after the
carriage, letting it rest on suitable rollers. The pan carriage empties its salt into
waggons J fitted with suitable wheels and axles, and running on rails in a
sunken passage K, but which I sometimes arrange to run round the outside of the
pan, and be there supplied with salt by the pan carriage, which in that case delivers
its salt at the other end. The carriages are arranged with sloping ends j which
overlap one another successively along the train of carriages, so that any salt falling
on a division passes into one of the carriages right or left of it. The brine in the
carriage runs into a trough arranged underneath it or at one side from which it is
afterwards pumped back again into the pan. The rails on which the carriages move
pass round the circular passage K of each of the pair of ring pans for which they work.
These two circles are connected by points and rails to straight lines K 1 and K 2
which pass under the pans. A wire rope suitably driven passes on rollers along
the straight passages and round the circular range of the railway, and is arranged
to drag the carriages backwards and forwards as required. When the pan carriage
is at work near the brine heater, the rope is fastened to the last carriage, and the
waggons are backed round the part of the circle where the pan carriage is working.
The waggons empty their salt into hopper L which feeds an elevator Lx delivering
its salt into centrifugal drier E, and so on to the store H. M. are the boilers supplying
steam to the two brine heaters C and driving the machinery connected with the
works. The waste heat from the boiler flues may either be passed to the chimney O
by the flue o or be caused to heat the circular pans N in each building by passing
along low flues mx to near the centre of the pans, where it rises and feeds the spiral
flues m which discharge their spent gases by the flue ox to the chimney O. In
some cases I pass the gases round the flues in the opposite direction. In the centre
of each circular pan there is an arrangement, see Figs. 27 to 30, for causing the
upper and lower stratum of brine to flow from and to the centre to the sides of
the pan, preferably also giving it a slight whirling motion to equalize the current.
The pan is scraped by inclined scrapers attached to the rotating arm P, which is
supported in bearings at the centre, and has wheels running on rails round the
side of the pan. It is made self moving, and serves to keep the bottom of the pan
for the most part free from salt, which it heaps up into numerous ridges, and
transfers the salt gradually till it falls into a pocket n in connection with the upper
part of c by a channel r in which there is at the bottom endless scrapers or a
revolving screw feeding elevator D. There is a passage S from between the pans
to get at the driving machinery under the centre of N, and a passage X round the
inner pan, and also one at the side of the waggons. Perforated pipes are preferably
placed around the sides of the pans, and warm air is blown over their surfaces to
assist evaporation. The lower part of the building is solidly constructed and the
whole roofed in and lighted, openings being provided for the steam from the pans to
escape. In some cases I dispense with the inner pan, using the place vacated for a
stove or store. I apply this system of circulating the brine in ring pans on a
smaller scale, sometimes using pans with metal bottoms and heated by furnace
gases, steam, or otherwise. When so doing I dispense with the brine heater and
employ pumps, paddlewheels, or other means for circulating the brine round them.
In another arrangement I employ spiral pans, either of wood or metal, so as to
obtain a very long current for the brine. In this case I either place a brine heater
at one end of the spiral and withdraw the cooler brine from the other, or I place
the pan over corresponding spiral flues and employ pumps or other suitable arrange-
ments for transferring the brine from one end of the spiral pan to the other to
make the circuit of the brine continuous.

page_text: Figs. 25 and 26 are a front and plan view of an arrangement for two pairs of
right and left deep circular pans forming a group of four pans with appliances for
working the same. The salt is removed from these pans at intervals by the brine
being drained off from each as it is ready for emptying when men pass through
water tight doors at their sides. The brine is circulated in the larger pans by jets
of brine or machinery, and in the lesser ones by the current of heated gases passing
over the surface of the brine. A and Ax are a pair of deep pans arranged in
duplicate, so that one may be kept working whilst the other is being emptied, as
is also arranged with the smaller pans Q, Qx. The pans A have central pillars b
supporting girders or beams radiating from the centre over the brine in the pan
to the side walls. A covering e is provided for the pans, preferably fastened to
the under side of the girders or beams. It forms a passage for the hot air, which
is blown over the brine from the sides of the pan by an encircling perforated pipe
or channel b to pass into the central dome or opening g, from which it is conducted
by a passage h to the chimney I. I sometimes reverse the course of the heated
air, arranging for it to enter the case at g, and be withdrawn or allowed to escape
at the outer edge of the case e. The pans A and Ax are preferably heated by a
brine heater J of the type shown, Figs. 59 or 61, which are connected with it by
pipes K between the bottom of pillar b, see Fig. 31, and the cisterns at the end
of the brine heater. The hot brine passes up the pillar and issues from a case near
its top in such wise that a current of hot brine is sent out on all sides from it
The hot
towards the sides of the pan, preferably with a slow whirling motion.
brine passes over and amongst the crystals deposited at the sides of the pan, and
there sinks, returning along the bottom of the pan to the openings round the
pillar b at bx, when it is withdrawn by the channel L and returned by pump m
and pipe n to the brine heater J for further heating. In L there are endless
scrapers o or a screw which removes any salt getting into the trough to the pocket
of the elevator ox, which raises and delivers it into the pan or elsewhere. Pare
the boilers for supplying steam to the brine heater by pipe p, also to the pump m
and where else required. The waste gases from the boiler flues pass under the
pans and Qx by flues 7, and rise up the central pipes s, where they preferably
The pan
is
circle round the spiral flues c, and finally escape up the chimney I.
covered in with thin metal plates U fastened to the under side of the radial
girders or supports ux; the converging ends of the supports are bolted to projections
from the tube s. The sides of the spiral flues under this cover are formed by
rivetting thin vertical strips of metal t1 on its under side, the same being arranged
to dip a short way into the brine. The force of the draught along the spiral flues
causes a slight whirling current with the brine in the pan. Over U the thin metal
coverings to Q and Qx are cases for heating air. They are formed by fastening
thin plates of metal or planks on the upper side of the supports or girders ux.
Air for these cases is admitted at the outer edge of the case, and withdrawn from
its centre over s by pipe vand pump w, by which it is blown over the surface of
the brine in pans A, Ax, by the perforated encircling tubes 6 placed round the
The salt from these
edges of the pan under the cover, as previously described.
pans is removed by first draining a pan and then entering it through the water-
tight doors placed at a 1 and g 1, or in any convenient position. The pans are
arranged in duplicate, so that those on one side may be worked while one or more
of those on the other are being emptied. I sometimes admit hot gases from the
furnaces on the outside of pans Q, Qx, and cause them to travel the reverse way
along the spiral flues, withdrawing them at the centre by a chimney or otherwise,
and occasionally dispense with the divisions and pass them over the brine in the
pan by a circular perforated flue round the pan. The hot vapours coming from
pans QQx, are sometimes usefully employed in heating brine in other pans.
Occasionally in these and other circular pans I cause the rotating current of the
brine by employing directing jets, through which I force brine into the pans at
the sides or elsewhere in the direction in which it is required to cause the
circulation.
-

page_text: Figs. 27 to 30, enlarged side views of arrangements for circulating brine in
circular pans so as to produce an upper and lower current, preferably with a slight
whirling movement to equalize the same, also central support and driving for arm P,
Fig. 23, which travels round the pan edge on rails. A, the central part of a
circular pan; B, a metal arch or dome over passage cx to support the vane case;
C, walls of passage; D, side flues; E is a circular case bolted to B or otherwise
supported. It is arranged with inlet and outlet channels e and ex round its bottom
and just below the level of the brine at its top. The channels are subdivided and
the divisions are curved, as shown in plan, Fig. 28, for e, and curved in the opposite
direction for ex. The lower channels turn up at el under a revolving vane F,
and are arranged to feed it with brine from the bottom of the pan. The vane has
sloping radial plates f, and above it there is a cover e with similar plates sloped
the other way, and so arranged that when the vane revolves it draws brine in to
the case at e, and passes it out again at ex, or vice versa. The cover e 2 rests on a
ledge at the side of the case, and is bolted to the latter. The vane is keyed on a
vertical shaft h 2 carried in bearings at the top and bottom of the case at Ex and e 5,
where it passes through a stuffing box and is driven by a wheel h 1 by the wheel hx
on the end of shaft H, which is turned by an engine below (see S, Fig. 23), or
otherwise. The top of the case c4 is made removeable to get at the vane.
It
usually supports one end of the long arm (P in Fig. 23), which reaches to the side
of the circular pan and drags scrapers over its bottom to ridge and remove the salt.
It is here marked G, and rests on bearings supported by curved ribs on the top of
the case.
I is an annular floating board to equalize the escaping current; I is a
worm wheel on the shaft i turned by the worm 3 on shaft h 2. The shaft i is
carried in bearings at G×, and drives one or more wheels at the other end of G to
make the arm travel round the pan. I sometimes drive the shaft i by bevil
wheels as shown, Fig. 30. The inlet and outlet channels e and ex are sometimes
made with straight instead of curved divisions, or so arranged as to counteract the
whirl of brine in the case, and send out a radial flow of brine from the top.
Fig. 29 is a similar style of apparatus but arranged with a revolving cover ex,
arranged so as to keep the current more evenly distributed over the pan. The
weight of the end of arm G is supported by the cone I, which has openings i near
its base through which the brine passes. The curves in ex are cast to the top of
the moving cover, which is preferably made in halves bolted together and turns on
bearings at E. It is caused to turn by one or more projections y from the arm G.
Fig. 30 illustrates how the current through the case may be produced with a
revolving screw J; also the way in which in place of a stuffing box for the central
shaft to pass through (as shown in the previous Figures, and which I sometimes use
for this case), there is a tube K fastened to the bottom of the pan through which
the shaft marked Jx passes. The tube rises above the level brine in the pan. On
its outer side is a larger tubej fastened to the top of shaft Jx at jx and turned by
it. The screw blade J is attached to this outer tube. The shaft i on G is turned
by bevel wheels 1 and 2 driven by shaft Jx, which is carried in suitable bearings
and driven slowly. In some cases I drive this shaft from over the pan, or in place
of using shafts with revolving vanes, use discs or screws for circulating the current.
I sometimes dispense with them and employ a centrifugal or other pump for the
purpose. A division is placed across the case at e 3, dividing it into upper and
lower compartments, from each of which I carry a pipe to a pump (preferably
centrifugal, and placed under the pan). I sometimes use revolving discs in the
centre of circular pans to produce the current of brine, placing them on vertical
shafts driven from under or over the pan.
Fig. 31 illustrates the means preferably employed for circulating the brine in
deep circular pans like A and Ax, Figs. 25, 20; A is the central portion of deep
circular pan; B, space over pans for currents of warm air; C, scraper trough under
pan; E, masonry; F, central hollow pillar supporting girders or beams G radiating
to the edge of the pan, and there supported on walls or framing. These beams
support the cover of the pan which is preferably fastened to their under side;

page_text: H, pipe supplying heated brine; I, passage for brine up the pillar; i, holes in
upper part of pillar for escape of brine; J is a case to receive the brine and
preferably revolves. It causes the brine to pass into the pan a little below the
level of the outer brine by curved channels j like e, Fig. 28, or with channels
arranged for the description of current required. The case is continued down the pillar
to f where it is supported on bearings, and carries curved arms jx which scrape any
salt coming near is down the opening and passage e leading to the trough C, where it
is removed by endless chain scrapers Cx to a pocket and elevator on the outside of
the pan. The case J is steadied by a projecting ring or bearing round the pillar
at It is turned by a rack j 2 placed round its top in gear with wheel kon
shaft Kx, on which there is a bevel wheel in gear with 7 turned by the shaft L.
The brine is withdrawn from the bottom of the pan through trough C, passed
through a brine heater, preferably of the type shown, Figs. 50 or 61, and when
reheated again enters the pan by pipes H, I, and the revolving case J. I some-
times pass the brine over instead of under the pan, or both over and under it;
occasionally I dispense with case J, arranging jets or channels fixed to the top of
the pillar to give the desired circulation to the brine. The opening c is then made
larger, and salt collecting near it is pushed down it by a tool put through the
cover of the pan.
there is a
Figs. 32 and 33 are end and side views on an enlarged scale of a pan of the
ordinary rectangular type, arranged so as to lessen the amount of pan scale
produced especially over the furnace plates with improved combustion in the
furnaces and other improvements. A is a pan of any suitable length supported on
the side and end walls, and preferably numerous short metal pillars underneath in
place of flues in the space B, by which means more of the pan bottom is exposed to
the heating gases and vapours than when a large portion of the space is occupied
by brickwork. I preferably arrange water joints round the pan on the outside, as
illustrated, Fig. 49; C are furnaces narrower than those ordinarily used under salt
pans, with cases for heating air placed between them. The furnaces are fitted with
rocking bars D regularly supplied with fuel by self stokers Dx from large hoppers F
above. These hoppers are filled at intervals by tipping waggons F 1 running on
rails Fx. Over the furnaces, and preferably from side to side of the pan,
long tank E arranged with a sloping side f not quite touching the pan, excepting
where it is bolted to it, and so arranged as to blow a sheet of steam under the pan
bottom. The object of this arrangement is to produce a large volume of mixed
vapour and gases at a reduced temperature to lessen the production of pan scale
and prevent the pan plates becoming over heated and fusing salt on their upper
surface. The tank is made self feeding by suitable valves and floats, preferably
placed outside the walls and connected with a supply of water from a higher level.
Means for entering the tank and draining it when required are provided. I
sometimes use a separate tank for each furnace, but prefer one long tank, which is
easily entered and repaired. Across end flue G is arranged at the end of the
space B, with numerous side openings between the divisions g to keep the gases
well spread out over the width of the pan. It connects to H leading to another
pan, chimney, or elsewhere. I is a perforated pipe placed acress the end of the
pan to withdraw the brine and keep the current well spread out in the pan. It is
connected with the pump J, preferably driven by its own engine Jx. The pump
forces the brine along the pipe K, and into a perforated pipe L, and also extending
the width of the pan. The current circulates between L and I. M is a water pipe
for flushing pipe K; N, loose handle for moving valve O to supply brine or water
to the pump; P, pipe to drain off flushings; Px, valve and handle; Q, air chamber
at the side of the furnaces, into which air is forced. They are connected with
and supply R. A central air pipe supported on rollers 7 to keep air at an even
pressure in the various side pipes T; S and Sx, connecting pipes from R to
perforated side pipes T and end pipe Tx which blow heated air over the brine
to assist evaporation; U, stuffing box or joint for expansion and contraction of
tube. I employ various styles of pump for circulating the brine in pans, preferably

page_text: employing those of a centrifugal kind. I sometimes use double or treble acting
pumps so as to provide a more steady flow of brine down the pipes and pan. When
using single acting pumps I arrange a cistern above the pipes, into which the
brine is pumped and arranged to feed the pipes regularly, or use compressed air
bulbs, after the usual manner. The object of providing for the introduction of
brine into the pan in a 'steady even flow is to lessen the percipitation of minute
particles of salt, usually forming on the surface of the hot brine over the furnace
plates in the pan. The pumps, pipes, tank, air cases, and other metal work about
the pan or furnaces are preferably coated with black or magnetic oxide according
to a well known process. When erecting new metal pans I prefer also to coat
their plates with black oxide, as in fact all machinery or ironwork connected with
evaporating brine or manipulating salt, whether in a pan or elsewhere, about salt
works.
Fig. 34, side view, illustrates a system I employ for heating air for pipes T in
pipes A placed over the furnaces from side to side of the pan, which, in combination
with a sheet of steam or fresh air blown under the pan by the perforated pipe B
assists in protecting the pan plates over the furnaces from excessive heat, while
increasing the volume of heating gases passing under the pan and lowering their
temperature.
Fig. 35 is an arrangement for transferring brine from one half of a divided pan
to the other by means of a subdivided trough or end to a pan with the assistance
of paddles or otherwise, so as to keep the current spread out in both pans; A, pan
with brine flowing towards end; B, the subdivided curved end, which I sometimes
arrange with straight sides instead of curved ones; Bx, partial division over and
under which brine flows; C, row of paddle wheels on one shaft to pass brine
equally along each subdivision of curved end, and so equalize the flow of brine to
and from the end of the pan; D, pan to which brine is transferred from A.
Fig. 36, the ends of two pans A and F placed side by side with brine being
transferred from A to F by perforated pipe B, pump C, connecting pipe D, and
perforated pipe E. In place of the perforated pipes B and E I sometimes employ
troughs or inverted cases in connection with the pump C and pipe D.
Figs. 37 and 38, side and plan view of pans adjoining a stove, illustrating how I
prefer to apply the current of brine to twin pans, withdraw vitiated air from the
stove, and improve evaporation by blowing it over the pans. A, left pan; B, right
pan (twin pans); C and Cx, perforated exhaust brine tube for A pan and B pan;
D, connecting pipe to pump E. The pump is common to both F return pipe,
common to both G connecting pipe to H; and H×, perforated supply pipe for A pan
and B pan; I and Ix, water pipes for flushing; J and Jx, pipes to remove
flushings; K, stove next to pans; L, perforated pipe placed along the side of stove
to withdraw vitiated air from stove and pass it on to pump M which blows it
over the pan by the connecting pipe N and perforated side pipes 01, 02, 03, 04;
P, stove wall with entrance to stove; Q, platform round pans; R, shaft and wheels
for driving pumps and fan; they are, however, preferably driven by little
independent engines fixed to them so as to avoid having belts in the steaming air
of the pan room.
Figs. 39, 40, side and plan view of the end of a pan in which the brine is circulated
up the middle and down the sides, or vice versa, by top and bottom openings in a
division placed across the pan or otherwise in combination with heating surfaces
scraped by machinery. A, pan in which there is a too and fro current, shown by
arrows, or vice versa; B, division with top side openings b, b, for hot brine to escape
into pan; C, slope under division to deep portion of pan Cx for return brine to
enter under division; D, the steam pipes for heating pan; d, steam cases at end of
pipes to which they are fastened; E, steam supply from boilers; F, condensed
water pipe; G and Gx frames of reciprocal pipe scrapers; g, scrapers; gx, rods by
which the frames are moved, passing through stuffing boxes g1 and coupled to
levers H, Hx, by connecting rods I and I×; J and Jx, cranks with suitable con-
necting rods for moving levers H and Hx; K, crank shaft; L, screw wheel turned

page_text: by worm n on shaft of engine M: 0, chamber arranged under pan to save room.
I sometimes arrange machinery in front of the pan when room is plentiful. Q, level
of platform round pan; R, walls or support to pan. I employ various styles of
engines for driving the scrapers used for steam tubes or other heating surfaces for
pans, but prefer 3 cylindered engines, which I have generally illustrated for the
purpose, as occupying little space and working smoothly. Where several pans are
placed side by side I generally arrange one or more long shafts suitably driven to
move the machinery for several pans, and dispense with a separate engine for each
pan. In some cases I arrange for the removal of scale from heating tubes and
surfaces by soaking them in solvents, and afterwards when the scale is softened
remove it by hand scrapers,
Figs. 41 and 42, side and plan view of pan arranged for this object. It is heated
by pipes placed in cisterns which can be emptied alternately without stopping the
pan, so as to be filled with a solution of caustic soda, sal ammoniac, or other solvent,
to facilitate the removal of scale from the heating surfaces. A, end of pan heated
by pipes in cisterns B and B 2 made in duplicate; C, heating pipes placed in rows
over one another; D, steam cases at ends of pipes to which they are bolted. The
central case is divided for supplying steam to either side. d, condensed water
pipes; E steam pipes from boiler to central case; e and ex, handles directing steam
to pipes in cisterns B1 and B2; F, pipe bringing up cool brine from pump or
otherwise; and fx, valve handles; F 1, valve for cistern B 2. There is a space left
between the two rows of pipes c for a man to get down and clean the pipes. The
brine entering by F sinks to the bottom of this space, and is then directed by the
moveable divisions G and Gx to rise amongst the hot tubes above and overflow to
the right and left. The divisions are supported on rollers g running on rails b
placed across the cistern. When the pipes on one or both sides require attention
the divisions are alternately drawn back and room left for the workman to operate
on them; Hand I, front overflow trough; h, division with openings at bottom to
pan J, K, back overflow troughs; Jx and Lx, curved channels to M, a large
valve or cock on a steel centre to direct current into H or I; N, regulating handle
on shaft, to which is keyed a pinion nx in gear with cock wheel m; o, pipe for
admitting and withdrawing the solvents. A second pipe is provided for with-
drawing brine from cisterns; P, stair ladder to platform Q to get at valve handles.
By arranging the sides of the cistern higher than the brine in the side troughs or
pan into which it overflows, either cistern can be alternately drained free from
brine, the pipes put in to soak, and afterwards cleaned, by moving the division g
for a man to scrape the softened scale off the tubes, after which the cistern is
washed out and again filled with brine and restarted, when the other one can be
similarly treated. When using strong acid for the removal of the scale from heating
surfaces I arrange as far as possible for them, or at any rate their containing vessel,
to be made of pottery or of such material as will withstand the action of the acid.
Another variety of pan for the same object as the last is shown in Figs. 43, 44, and
45, with a side plan and detail view of a pan heated by pipes in three cisterns arranged
for the withdrawal of brine and admission of solvents to clean the pipes. A, end
of pan.; B, division with holes or slit at bottom, forming trough C; D, second
division, whose top is a few inches higher than the brine in pan, and over which
the brine from cistern falls into trough C; E1, E2, E3, alternate cisterns
fitted with steam pipes F, F, set side by side; Fx, steam cases at end of pipes, to
which they are fastened, see Fig. 45, showing division F, separating steam for one
set of pipes from condensed water draining from another; fx, supports with steam
and water channels. G 1, G2, G3, connecting steam pipes from H with valve
handles g 1, 2, 3; H, main steam pipe from boiler; 1, condensed water pipe con-
nected with cases by pipes i; J, brine supply pipe from Jx, a pipe leading from a
pump or higher level than pan; j, vertical brine pipe; j 1, valve supplying brine
to K, a perforated pipe set back over edge of pan to allow raking from under pipes
to be raised out of deposit trough L; M, sloping bottom of pan under pipes; N,
floating boards to lessen evaporation, one for each cistern; n, lid to same, to avoid

page_text: uncovering the pipes when withdrawing deposit; O, drains connecting with P and
Qby pipes and q, controlled by valve handles px and qx; P is connected by
suitable pipes and valves with a cistern containing solvents, with which to fill and
empty the cisterns in the pan for removing scale from pipes; Q, drain for brine
from pan cistern.
The
With the object of heating deep wooden and other pans where a considerable
depth of salt may accumulate, and also of arranging a continuous top and bottom
current in the brine therein, in combination with heating surfaces that are provided
with moving scrapers to make them more effective, I arrange long or square pans
with pipes or cases of pipes preferably placed across their middle, and cause the
current to flow to and from the pipes and upwards through them by placing partial
divisions at their sides. An arrangement of this description is shown in Figs. 46, 47,
where the central portion of the side and plan view of the side of a deep pan A is
heated by a set of pipes marked B. The pipes are supported at their ends by
cases Bx placed at intervals along the pan to lend support to the pipes, and to
collect and drain off the condensed water by suitable pipes which are connected
with them for the purpose. They are supplied with steam by pipes C, which are
provided with regulating valves and handles. Although preferably heating pipes
of this description with steam, I sometimes use larger pipes, and blow or draw hot
gases through them in place of steam, or mixed with steam when larger pipes or
conduits are preferably connected with the end of the first and last cases.
cases are supported on walls D. e are the frames to which scrapers encircling the
pipes are attached, and arranged to be moved by long rods E, which pass through
the various steam cases in holes or pipes cast or made for them to pass through,
which at the side of the pan are provided with stuffing boxes ex.
The rods are
connected by a cross head e 1, and are coupled to connecting rods e 2, by which
they are moved backwards and forwards between the steam cases Bx by suitable
cranks or other machinery. A long trough F passes under the various cases, and
is preferably lined at the sides with wood. It is provided with endless scrapers G,
which convey the salt accumulating in it to a pocket elevator for its removal or
otherwise. A space H is provided under the trough, preferably made high enough
for a man to pass down. There are plates or boards I arranged at the sides of the
pipes, which nearly touch the bottom and allow the brine to flow over their top,
causing the cool brine to enter below the pipes, rise up amongst them, and escape
heated over them. In this way the brine is caused to flow towards the pipes along
the bottom of the pan, and away from them at its surface, carrying the nucleus
crystals towards the sides of the pan, where they accumulate and are subjected to
a hot current of brine passing down, amongst, and over them. The fine salt
brought by the lower current passes upwards amongst the tubes back into the
pan; the heavier crystals fall to the bottom of the trough, and are removed by the
scrapers G. J is an arrangement of floating boards placed over the pipes to lessen
evaporation. It is provided with a central division j, and serves to direct the
opposite currents to the two sides of the pan. In some cases I cimploy this pipe
arrangement for heating brine in pans at one side of the pipes only. I sometimes
employ pipes or heat conveying cases of large diameter fitted with scrapers and
side boards I. In some cases I place an arrangement of pipes of the above
description in a central trough with sloping sides, connected with shallow pans to
the right and left of it, which it feeds with hot brine through openings in divisions,
after the style of B in Fig. 40 or otherwise.
Fig. 48 is a side view of a deep pan, preferably of wood, arranged for continuing
at work untill containing enough salt to fill a boat or a number of waggons on rails
at the sides when it is stopped, and the salt emptied either over the side or by
suitable watertight doors at the end, side, or bottom, in which latter case I arrange
a waggon way under the pan. The pan is arranged so that at whatever level the
salt may be, there is nearly the same surface current of brine over the salt from
end to end of the pan; A is the pan, suitably supported and preferably arranged
with a sloping end at Ax and a float at B the other, below which its bottom is

page_text: slightly depressed. The brine is introduced into the pan at Ax, and withdrawn
at B, causing a current down the pan; H is a circulating pump supported by
masonry, which forces the brine through the long and turned up pipe I into the
brine heater K, supported on walls Kx, and over the sloping end of the pan to flow
down the pan to continue the current. The end of the pan at Ax is sloped, so that
at whatever the height of brine in the pan may be, the entering brine runs down
the slope untill it meets the brine in the pan, which it joins with little disturbance.
I sometimes introduce the brine at the bottom of the pan by a perforated pipe
placed across its end, or from under a division nearly touching the bottom, behind
which I pour the current or otherwise. In these latter arrangements I place
floating boards over the incoming current to reduce the disturbance of the surface
brine. The brine is preferably withdrawn from B by a perforated tube b the
width of the pan supported by two floating boards 61 and 62, connected by ties
with a space between them, so that the numerous holes in the pipes b may be
pricked or cleaned from above. To this tube there is a vertical pipe C passing
through a stuffing box D, and moving up and down in a larger tube E placed under
the pan. F is a curved pipe connecting E with the pump H.
It has a pipe,
valve, and handle at G, to drain the pan when ready for emptying. Hx is a pipe
for admitting fresh brine or for flushing the pipe I when I introduce a drain pipe
and suitable valves in I at Ix. I is a pipe from the pump to J, a perforated pipe
at the top of the brine heater K placed across the end of the pan. The brine sinks
down the deep channel 1, on the side of which there is a wooden lining, into the
screw trough m, where there is a revolving screw n communicating with a pocket
or elsewhere. O is a steam case enclosing and heating two rows of pipes p, which
are scraped by revolving scrapers turned by the wheels q and qx by a worm shaft r
and wheel s, see Figs. 71 and 72. The brine rises up these tubes and flows over
the end of the slope Ax and again enters the pan. When first starting the pan,
only a few inches of brine are circulated, untill salt accumulates on the bottom,
when the brine is gradually raised to a higher level, as shown by the dotted lines.
The salt is preferably levelled at the bottom by hand or machinery, so that the
current may pass more evenly over and amongst the surface crystals, and add to
their growth and size. I preferably employ the system of increasing the depth of
brine in pans in proportion to the depth of salt they contain with all long pans in
which brine is circulated by artificial means.
Figs. 49 and 50, side and end view of an arrangement of pan, whereby salt may
accumulate to a considerable depth in a pan without diminishing the amount of
heat communicated to the brine through its bottom plates exposed to steam or
heating gases, or both. A is a pan supported by walls F, girders Fx, or otherwise,
placed over a deep chamber B, into which preferably steam or other heating
medium is introduced. I sometimes excavate the chamber below a pan, so as to
keep it low down. The heat used should never exceed the fusing heat of salt, and
the pans are best adapted for utilising steam from other pans or steam mixed with
products of combustion from a surface pan; C is the inlet for heat from the flue Cx ;
c, a grating over it; D is an outlet to flue Dx, also covered by a grating d. The
inlet and outlet channels are both placed low down, so that only the cooler vapours
or gases are withdrawn or allowed to escape, while the hotter impart heat to the
brine above. The bottom of the chamber is sloped with numerous cross channels
to draw off the condensed water by pipes, whose ends dip below the level of water
in the side gutters E, so as to stop cool air from entering the chamber. To prevent
the escape of steam or hot vapour at the top of the chamber under the pan where
it is supported all round by the outer walls F, I arrange water troughs G inside
and outside with side plates built into the walls, so as to prevent air passing
between them and the walls. Into cach trough I arrange a long strip of iron g
rivetted to the pan above, which dips below the water in the trough. The
troughs pass all round the pan inside or outside the walls. The troughs are
supplied with water by regulating floats and valves from a cistern at a higher
level, and arrangements are made to send a considerable body of water

page_text: I
along the trough to flush dirt into pipes or pockets, which I prefer to place
at intervals along the trough with means for discharging the impurities.
preferably adopt this system with all steam heated pans, and, where practicable,
with pans heated by furnace gases. I prefer to place the water troughs
outside the walls, where they can be more readily cleaned and are less liable to be
choked with ashes and soot. The pan has a double bottom a, ax; the lower one
is of metal, the upper one may be of wood, and the salt accumulating on the pan
remains on it untill removed. The upper bottom is placed at a short distance from
the lower one, and is supported by numerous strips of wood or metal placed length-
ways of the pan. Ax is a space between the two bottoms, it has a cross channel
the width of the chamber at Y and Z. The former is preferably supplied with
brine by a perforated pipe a 2, which is arranged to distribute the current evenly
across the space between the double bottom; it is connected by the pipe a 1 to the
pump H. The channel Z has two pipes I, J, leading from it with valves and
handles and j; the upper one conveys brine or brine and water to a cistern or
elsewhere, while the lower one is connected with a drain. On the right above Z
there is a division a 3 rising above the level of the brine in the pan, and forming
between it and the end of the pan a continuation of the space Ax; it discharges
the brine pumped through the double bottom behind a screen or partial division a 4,
which is provided to lessen the disturbance of brine in the pan by the entrance of
the current. The pump is suitably supported and preferably driven by its own
engine Hx worked by steam or air. His supplied with water or brine by a pipe K,
or brine from the pan by a connection with the curved channel L extending along
the end of the pan, in front of which there is a long vertical strainer to hinder
small particles of salt passing from the pan into the pump, and placed vertically to
lessen crystals resting on it and facilitate its being cleaned. There are valves and
handles x and x to regulate whether the pump is supplied from K or M. In
front of the strainer there is a deep cross trough N partially separated from the
pan by two partial divisions a 4 and a 5 in such wise that a 4 forms a back for the
salt in the pan to lodge against, and allows the brine in the pan to flow over it,
passing downwards under a 5 into the trough N so as to incline any particles of
salt carried by the current to fall to the bottom of the trough and lodge there before
the brine is withdrawn through the strainer to the pump. I sometimes sink the
floating crystals coming up to a 4 by placing a perforated air or brine pipe or
channel over the pan in front of the division, and blow air or shower brine on the
surface of the current so as to sink and trap the crystals. Occasionally I use an
agitator placed across the pan in front of a 4 for the same purpose. I employ this
system of sinking crystals and straining brine whenever it is necessary to keep the
pump free from minute particles of salt. The brine withdrawn from N is forced
quickly through the double bottom Ax, where it acquires heat from below and again
enters the pan from the other end. The double bottoms should have but a narrow
space between them, so that the brine may be caused to pass quickly in Ax without
creating too strong a current in the upper pan. When desired the valve lx is
closed and the valve i opened so that the brine may run off as far as it will by
pipe I, or be forced out with water by opening the valve Kx and j. The double
bottom is thoroughly flushed out with water at intervals so as to wash out any
particles of salt that may have collected within. When the upper bottom is
of wood the pan should be first emptied, if of metal forming a watertight compart-
ment then the operation may be carried on while the pan is still full of brine.
some cases I introduce solvents or steam between the double bottoms. O is a
platform between the two pans on which the salt from the pan may be drained by
the sloping case o under it. Draining into a gutter ox there are trap doors o 1 covering
holes o2 in the platform, through which the salt is passed into waggon P running on
rails beneath.
In
Figs. 51, 52, side and end view; 53, 54, plan details of an arrangement wherein
the heating chamber under the pan, by the use of circulating channels and
pipes for the brine, is reduced in width so as to permit the arrangement of store

page_text: rooms under the side of the pan and side passages between the heated chambers,
or at their sides. A is the pan, preferably made of wood, supported on beams or
girders B by walls C, pillars D, or otherwise; d is one of several pillars for
supporting the roof when required; E is the heating chamber with a longitudinal
division e dividing it into two portions e1 and e 2 connected by the opening e 3
placed low down, and a door e 4. The heating medium is introduced at the further
end of e 1, traverses the length of the chamber, dips down and passes through the
opening e 3, retaining the hotter vapour at the top of e 1, and returns by e 2 to
the former end of the chamber, from which it is withdrawn by the flue Ex, also at
a low level, to the chimney or elsewhere; suitable flues, pipes, or channels are
provided for introducing and withdrawing the heating medium employed. Under
the bottom of the pan is a series of pipes or preferably a case G, which forms a
covering to the heating chamber E, and which is subdivided into separate channels g,
see plan view, Fig. 54. These are fed with brine or water by the pump F, by
pipe f, and a perforated tube fx placed in a cross depression at the end of G after
the style of the arrangement of Y in the last pan. The subdivisions g converge at
the other end of the case, as shewn by Fig. 53, and pour their contents into a pocket H
fitted with a sloping or hopper bottom connected with pipe h, and a valve regulated
by handle hx. This pocket is arranged to receive crystals carried by the current.
From its upper side are two rows of pipes I running nearly the length of the
chamber, and discharging their contents into a second pocket J extending from
side to side of the chamber, and arranged with one or more pipes j, and with valves
and handles jx. From the upper part of J at the end of the chamber e 1 there are
again two rows of pipes K which extend nearly the length of the chamber, and
discharge their contents into a trough L at the end of the pan, and extending from
side to side. The same arrangements for the admittance of brine to the pans, and
its withdrawal at the other end by the pump, are employed for this pan, as on the
last, partial divisions, pockets and strainers being similarly used. The brine is first
pumped through the case G, or tubes in its place, where it receives the heat from
both the chambers e 1 and e 2, and deposits any crystals that may have passed the
strainers into pocket H. It then passes along the pipes I placed in the cooler of
the two chambers into pocket J, where it again has an opportunity of depositing
floating crystals before returning by pipes K in the hotter chamber to the trough L,
to re-enter the pan between the divisions m, n, as in Fig. 49. By the use of
shallow or narrow passages or pipes for the brine to traverse a much swifter
current, preferably exceeding six feet per second, can be pumped through them,
thereby discouraging incrustation of salt in the pipes and passages, which is a
matter of importance. Provision is however made for flushing out the case G and
pipes I and K. F1 is a pipe admitting water or solvents for the purpose, which is
pumped through the case, and drained through the pipes h or j, or by a pipe at the
bottom of the trough L. The pipes and top case are preferably supported at
intervals by cross bars or plates O built into the wall through which the pipes pass.
When the pans are very long I support the pipes on rollers, and arrange for their
expansion or contraction with rollers, stuffing boxes, joints, or otherwise. The
upper portion of the chamber should be made so that the vapour does not escape,
for which purpose I generally employ water joints, like G, Fig. 49, or otherwise.
Pare side passages and galleries by the pans for operatives to rake out the salt,
which after draining is passed through the trap doors or openings px placed on the
alternate sides of the passages into the storeroom R below. Qare sloping coverings
to the store to drain away any brine that may leak from the pan or come from the
salt on the platform p into a gutter q for its removal; doors S are provided at the
end of the store room for the admission of waggons T running on rails u for
the subsequent removal of the salt; suitable entrances are provided to the heating
chambers of this pan, and that previously described, and the pumps, engines,
pipes, galleries, and pans, are suitably supported by masonry, girders, beams, or
otherwise.
Figs. 55, 56, end and side view, showing arrangements for utilizing the steam

page_text: from the dome of my table pan A, for passing an increased volume of heat through
the flues at a reduced temperature, to lessen the formation of scale on their heating
surfaces. A, table pan, previously described in Patent No. 1336 of 1878; B, end of
furnaces; C, cross flue supplying products of combustion to the various narrow
flues a; D, steam dome; E, E, pipes from top of dome; Ex, case for balanced
valve ex moved by shaft ex, lever e 1, and chain e 2. The pipes convey the steam
to case F, which is bolted or rivetted along the side of the pan, and so arranged
with suitable openings e, as to permit the heat from the furnaces passing through
into table flues a. The case either overlaps each of these openings, or has numerous
holes or slits provided on the top and sides of e, to blow steam into the flues along
the inner sides of the tables, as shown in Fig. 55, so as to mix the steam with the
beat from the furnaces and avoid overheating the table plates. fis a piece of fire
brick at the bottom of each opening, and fx a fire brick protection to the portions
of the case between the flues. G is the bottom flue into which the heat of the
table flues pass by openings g; H, a perforated pipe blowing steam or fresh air into
the flues which I sometimes use instead of or in addition to case F. I arrange
direct communication between flue C and the flues of the preparatory pans
governed by dampers, so that their heat may be increased if that supplied by G is
not sufficient. In the scumming pan I sometimes dispense with the gauze or
permeable surface on the drum, Fig. 8, Sheet 1, Patent No. 2106 of 1877, employing a
roughened surface in its stead, and withdraw the brine from under the ledge b 3,
creating the necessary current of brine to pass the scum on to the top of the drum
for removal by the scraper. preferably line such parts of the table pan above
and trough beneath as are not kept clean by scrapers with wood, which appears to
offer less facility for salt to adhere to its surface than iron. The products of
combustion and steam after passing through the tables and flues of the apparatus,
are preferably afterwards passed under one or more adjoining pans, or otherwise
utilised. The fine salt coming from the table pan is preferably passed with brine
through a mixing tub or otherwise into these additional or other pans to acquire
size. When using this variety of table pan to supply other pans with hot
brine, I preferably withdraw it from near the surface of the brine, and sometimes
place floating boards to check evaporation. By mixing large quantities of
steam or fresh air with the furnace gases before allowing them to pass through
the flues of the apparatus, or under pans both here and elsewhere, the for-
mation of fused salt on the heating surfaces is prevented or greatly reduced.
There is still however in ordinary brine a small per centage of lime and other
impurities, which in time coat heating surfaces and render them far less efficient
than they should be, and with a low heat practically useless. The formation of
this lime scale may be largely hindered or prevented during formation by constant
rubbing or scraping. When forming, however, over the whole bottom of a pan on
which salt is constantly falling, as in the ordinary process of making salt, it is
difficult to get at and check. It can be ground off at intervals by an apparatus I
provide, described in Figs. 150-1-2, arranged to travel along the pan with a
reciprocating frame of rubbing stones or other hard roughened surfaces, arranged
for grinding the pan bottom after the salt has been removed, and preferably after
the brine has been temporarily withdrawn. I prefer however to combine the
advantages of a large evaporating and depositing pan or pans (preferably of wood),
with powerful heating apparatus, which I connect with the pans at their ends, and
arrange in a compact form so as to be easily kept constantly scraped by machinery
which I provide for the purpose, or be cleaned at intervals with solvents or acids,
as previously explained. The brine admitted to the pan or pans, or that which is
flowing in them, is forced or caused to pass through these apparatus in its circuit,
and is heated while passing through them. The apparatus for thus heating the
brine for the pans I term "brine heaters," and arranged in different forms, as
previously illustrated, and further shown in Figs. 57 to 79. In this way the scale
can be confined to a small space as compared with the large evaporating and
depositing surface of the pans usually heated, and is easily removed, while a thin

page_text: layer of salt may be beneficially allowed to remain on the bottom of the depositing
pans with which the apparatus is connected to offer a rough surface for fresh
crystals to collect on. I prefer when practicable to evaporate in the various pans
and apparatus brine from which the lime and certain other impurities have been
previously eliminated by the use of barilla, carbonate of soda, or other mineral
alkalies, and subsequent filtration or precipitation. This permits a simpler class
of arrangement or apparatus to be employed, and largely recoups the cost of
purifying the brine by the improved quality of the salt produced, and the larger
out put of the pans or apparatus.
Figs. 57 and 58, end and side view, illustrate a powerful "brine heater" arranged
to supply pans level with its top, as shown, Fig. 11. It also illustrates the way in
which heaters of this type, or where there is sufficient heat of brine, may be
constructed so that the scrapings falling from the heating surfaces can be removed
by flushing appliances in place of using endless scrapers, as in the last Figure.
I frequently, however, employ scrapers or screws in this and other apparatus,
illustrated with flushing arrangements, and vice versa. A is a table pan showing
arrangement of steam tables, scrapers, flushing pipe, etcetera; a, tables, steam
heated and suitably strengthened; ax, rotating scrapers between the tables to keep
their outer surfaces clean; a 1, central shaft passing through central tubes or openings
in the tables, and through the end of the pan by stuffing box a 2, turned by
wheel a 3 and screw, as in previous apparatus of this type. This sectional view of
the tables and means of scraping them illustrates the arrangement of the pan
previously described and those following of the same type. B, end of long pan;
C, pipe bringing up cool brine to the heater from a pump or otherwise; Cx,
regulating valve handle; c, short connecting pipes between C and side of pan
admitting brine between each pair of tables. The outflow of the heated brine à is
covered by floating boards e. The openings & are cast or made in a broad plate
laid in one or more parts along the top of the plan, which is arranged to lift up so
that a man may get down between the tables if required. F is the flushing pipe,
preferably connected with a cistern, as seen in Fig. 62. There are hoppers f
between each pairs of tables and at the ends of the pan to collect the scrapings
from above, and to allow them to be forced down the curved ends of the pipes
into F. fx are valves for shutting off connection between fand F. There is a
pipe f1 at end of brine heater connected with pan B and F, regulated by a
valve to scour out pipe when required. f2 is the handle of a valve to pass the
flushings in to a cistern, filter, or otherwise; Fx is a support for pipe F; by closing
all the valves but one and then opening the valve fƒ2 a considerable scour is
obtained through the hopper treated, removing the loose deposit from its bottom,
and passing it into the cistern, where it is preferably strained out, and the brine
passed back again into the pan. I prefer however to scour several hoppers at a
time and then give the pipe a wash out from the end. G, steam pipe from
boiler; Gx, cross pipe supplying steam to each table, carried on brackets g;
gx, handle to regulate steam supply; H, the condensed water pipe connected with
each separate table, as previously described; I, a passage under pan to get to the
valves. I sometimes arrange to open and shut the hopper valves by gearing and
a shaft passing under the pan, so that they may be open from the end of
the apparatus or otherwise. I preferably arrange clutch boxes on this shaft for
regulating the opening or closing of the valves for each hopper or set of hoppers.
Figs. 59 and 60 illustrate another variety of steamheated table pan as a "brine
heater," more especially arranged for heating pans at a distance or covering a large
surface, see Figs. 13-14, and 25-26. It is arranged with cisterns at each end, to
which pipes from the various pans are connected; A is the table pan fitted with
steam heated tables, scrapers, etcetera, as in Fig. 58. The tables are heated
preferably by high pressure steam, and their side plates of each are well tied
together and arranged for the purpose; B is the steam pipe from the boilers;
C, steam pipe at the top of pan to supply each table with steam by the short
connecting pipes c; D is the condensed water pipe to pump or boiler, if placed at a

page_text: low level; d, pipe placed along the back of pan with little pipes dx extending to
the bottom of each table to draw off condensed water; E, scraper trough leading
to pocket or elevator for receiving scrapings; f, endless chain scrapers as in previous
table pan; G, steam pump for circulating the brine through the pan between the
heated tables; g, supply pipe for pans; Gx, valve box to prevent the return of
brine to pump; 1, steam pipe; g 2, throttle valve; h, connecting pipe with
channel H arranged at the side of the pan with openings between the tables in
such wise that crystals passing through the pump get forced into the trough E by
the current of brine; I, opening between the tables to trough J, on which there is
a floating board; j, curved openings to allow brine to flow into trough K, and
arranged so that when the floating board is raised by an excess of brine being
passed through the pan, they allow more brine to pass into the trough below. The
bottom of the trough K is preferably made sloping from the middle towards the
hopper cisterns at each end, so that should any particles of salt be passed through
the heating pan and get into the bottom of the trough they are washed down into the
cisterns. The trough K on entering the cisterns turns down, as shewn at k 1,
to direct the current downwards; H. and Hx, are duplicate tanks with hopper
bottoms; is a floating board over the brine in each, to check evaporation; is a
lever regulating the speed of the pump engine by a connecting rod fastened to the
floating board h, and rod h2 regulating the throttle valve g 2. The hopper cisterns
are sloped at the bottom, so as to connect them with one or more pipes at the end
of each to convey the heated brine to various pans with which the apparatus is
connected. In this case there are duplicate pipes L and Lx, at each end, carried
underground to the pans; M is a drum for turning the scrapers. It turns the
screw wheel m on the end of the shaft of the revolving scrapers (see a 1, Fig. 58)
as in my previous Patents; mx is a stuffing box; m 1, scrapers in the pan between
the tables; N, elevator to remove scrapings in connection with trough E, and
preferably passes them into a filter, so that the hot brine will run back again
quickly into the pan. I prefer to drive the drum M either with a belt from the
pump engine, or with a little separate engine, arranged for the purpose, bolted on
to the pan or suitable framing connected with it; O is a high level gallery for the
superintendent to inspect the trough and hopper cisterns. It is approached by a
ladder, staircase, or any other suitable connection with the floors; O, brackets
for gallery. The pan is well mounted on masonry and concrete and covered in, as
are also the pipes in this and other heating apparatus with non conducting cement,
bricks, or other material to lessen radiation; P is passage under pan to get at tho
scraper trough, as previously described in my fire beated table pans.
Figs. 61 and 62, end and side view. This apparatus is arranged for flushing, as
previously described. It is designed for supplying several pans from one end
instead of from two, as shewn in the preceding Figure, and with pressure for pans
at a distance, or where currents are produced in circular or other pans by jets of
brine at their centres, sides, or elsewhere. A is a pipe bringing up brine to pump B,
arranged with an engine which turns scrapers by belt b to wheel B 1, on end of
whose shaft is a worm driving the worm wheel on scraper shaft; C, valves to keep
brine from returning to the pump when it is not working; c, pipe to case D;
D, case fastened to side of pan and arranged with openings between the tables, so
that it passes the brine downwards and carries with it any crystals travelling with
it and deposits them into the flushing hoppers at the bottom of the pan for
subsequent removal; E is a chamber over the top of the tables large enough for a
man to pass along to get down between them when necessary. When the apparatus
is working it conducts the heated brine to the end of tank F, where a pressure of
brine is obtained for distant pans and flushing out the hoppers under the pan. The
tank is supported on pillars fx and framing f1. F is divided at the bottom into
two hoppers, each charging two pipes f1, f2, ƒ3 (f4 not seen), governed by
valves Fx; G is a floating board on the surface of the brine to lessen evaporation,
to which is attached a rod g moving the lever gx, which regulates the speed of the
pump by rod g 1 moving the throttle valve of the engine. There are long board

page_text: valves g 2, preferably hinged on the outsides in the middle of the floating board G
to allow the escape of steam in case the pan is over heated; H is a hood with
doors at the sides and chimney to carry the steam off; I is a gallery round the
tank; J, the steam pipe from boilers; Jx, the pipe to supply tables connected by
pipes j; K, the condensed water pipe in connection with each of the tables;
Lis the handle of the flushing pipe; M, the tank into which the flushings pass;
it is fitted with a strainer to detain the flushings and allow the brine to be pumped
out for one or other of the pans.
b
Fig. 63, end view, shows another form of brine heater, with similar tables and
scrapers to Fig. 58, placed below two high level pans, or for receiving brine from
one pan and heating it for another, or for a ring or other arrangement of pan
which it heats and in which it circulates the brine without pumps. The brine for
this table pan comes up cool from the right in pan a and sinks to the bottom of
the heater by gravity and the directing curve 6 placed across the pan or entrance
to it. The brine may be supplied to a by means of a trough, or pipe, or channel,
from another pan with which it is connected. Salt carried by the current finds its
way into the scraper trough c, from which it is removed by endless scrapers to an
elevator or otherwise. The brine rises between the heated tables and escapes
through a line of openings d, partially covered over by the directing curved plate e,
and flows into the pan f to continue its circuit; g is a floating board. I sometimes
employ one over the near portion of pan a, especially when the apparatus is
supplied with brine from another pan. The steam in this case is conveniently
supplied at H by connecting pipes / to each table. The condensed water pipe I
is connected with the bottom of each table by pipe I; J is a girder supporting
the pan on the right, and K a wall on the left supporting the end of the pan f.
Fig. 64. This is a similar style of brine heater, where the difference of gravity
between cool and hot brine is used to cause the circulation in the pan above. It is
more especially designed for ring pans. A is a portion of the ring pan, described
in Figs. 23, 24; a is a board or division in slides at the sides, which is balanced by
chains and weights and withdraws to permit the travelling carriage to pass or for
other purposes; ax is a floating board to check evaporation over the openings at
the top of the pan and to assist in directing the current. The brine coming up on
the right sinks down the channel b to the bottom of scraper through C, carrying
with it any salt brought along by the current. The side of the pan curves round
to d, having openings between the table and trough for the brine to rise and be
heated in the direction shown by the arrow when it escapes through openings at
the top of the pan dx and re-enters the pan above to continue its circuit. The
scrapers e preferably turn from right to left in this pan, so as to pass the scrapings
more readily into the trough C. The pan is mounted in any convenient or suitable
manner. The weight of the tables is preferably carried by iron bars F set
edgeways, passing through the tables and resting on strong framing or girders G
supported by masonry on the two sides. The bars are longer on the right than on
the left to leave room for the brine channel 6 to have a nearly straight side bx for
the salt more readily to roll down into the scrapers trough C; a passage H is left
to get under the apparatus. The steam is preferably admitted by pipe E carried
on brackets ex and the condensed water is drawn off from each table by the
pipe I. J is the girder to support the end of pan A. I arrange various forms of
steam heated submerged cylinders, discs, or screws, for heating the brine for one or
more pans fitted with scrapers or cleaned with solvents. They are made to turn
and mounted in suitable bearings with the usual arrangements for admitting steam
and withdrawing the condensed water.
Figs. 65, 66, and 67 are the end, side, and plan view of a steam cylinder for
this purpose, with accompanying arrangements for heating a pan to which it is
annexed. A is a revolving submerged steam cylinder arranged with hollow axles
at one or both ends turning in bearings b and bx, with a stuffing box ax, and
provided with a steam tight joint with the steam pipe C, which is fastened to the
main frame B. At the other end of the cylinder here drawn there is an axle

page_text: turning in bearings bx, fastened to the frame B. A small pipe for condensed
water d, reaching down near the bottom of the cylinder, passes through the lower
portion of the pipe C, and empties its water into tank D, which is fitted with a
steam trap or regulating float and valve to allow the water to escape by the
pipe dx to the boiler or elsewhere, and prevent the escape of steam in the usual
manner. The cylinder is turned up true and may be mounted in various ways,
but must be steam tight, and arranged with proper provision for the admission of
steam and the escape of condensed water. It is preferably placed in a circular
casing E, which I prefer to line with wood. It is provided with stuffing box e
and ex, to let the pipe and axle of the cylinder pass through and turn while
stopping the escape of brine from the case. I sometimes use jacketed submerged
steam cylinders, passing the steam into the jacket. When using very large
cylinders I preferably employ rollers under their bearings or elsewhere. The
cylinder is slowly turned by a worm wheel F, worm g, and belt or small engine G.
There are preferably top and bottom scrapers h and hx, and end scrapers, not shewn,
to keep it as free from incrustation as possible. The circular case is open at the
bottom, where there is a trough H and endless scrapers I. In place of scrapers I
sometimes use a belt screw or flushing pipe, as previously explained. The
scrapings are preferably delivered into the pocket of an elevator J, which removes
them to a strainer over the pan, and lets the brine return to the pan. The
casing is bolted to the frame B, which is supported by masonry K or otherwise.
The apparatus is preferably placed at the end of a pan L, which is supported by a
wall M.
There is a trough at the end of the pan sloping from both sides to the down-
ward channel Lx, on one side of which there is a partition lx. The cool brine
sinks to the bottom of the casing, there depositing any small crystals that are
carried by the current. It then rises up the sides of the cylinder and issues at a
long opening in the casing at e 1, preferably under a floating board N; a trap for
small crystals likely to be sucked down by the down current on the other side of
an upper partition is provided at 11. The apparatus is preferably placed partially
below ground to save the expense of raising the pan to a high level. I prefer
following this plan wherever pans are supplied direct from the top of the brine
heaters. The sunken chamber O is provided with a ladder ox. It is partially
covered with boarding or grating o 1, o 2, so that the attendant may get at the
upper portion of the casing as well as the lower, and remove any salt collected
into 1, p; and px are raised passages round the pan for drawing the salt or for
other purposes. The casing is protected from radiation by being cased in non-
conducting cement. The effect of this system of heating pans is that the upper
surface of the brine travels away from the apparatus, and as it cools sinks to the
bottom and returns along it to the apparatus through which it passes and is again
reheated. I confine the current by placing boards over the central portion of the
trough ; the hot brine travels down the centre of the pan, and returns by the two
sides. By placing boards over the two sides of 1, and leaving the centre open,
and by arranging suitable upper corner boards or divisions from the top of the
apparatus nearly to the side edges of the pan, the current is reversed. I apply
this system with other brine heaters where the centre and side currents are
required, and when the apparatus draws its cool brine from the bottom and returns
it heated at the top. The casing is made in two or more parts bolted together at
the middle so that the upper portion may be removed when required for cleaning
or other purposes. I prefer however to use a solvent such as caustic soda or
sal-ammoniac for cleaning the interior of the case which is then arranged for the
purpose.
Fig. 68 is an end view of an apparatus of the same type, illustrated with a
brine supply pipe A to bring up brine from the further end of pan or pans with
which it is connected. It is also provided with a sliding bed B, like that of a
lathe, only preferably placed sideways with a central screw b. The bed is suitably
supported at its two ends on the framing of the apparatus, and is set true and

page_text: parallel with the axis of the cylinder. On this bed there is a self moving sliding
tool rest moved by the screw b so as to traverse from end to end of the cylinder.
The tool rest is made to screw up and down by handle cx, so that one or more
cutting tools c, which it carries, may turn off any incrustations of lime, etcetera,
formed on the cylinder as it slowly moves from end to end. The object of this
arrangement is to permit brine being heated in which there is a high percentage of
lime and other impurities liable to incrust the heating surfaces, and lower their
heating powers to a very low or useless extent. I employ the same system of
turning off scale in other arrangements employing revolving edged tools or planing
arrangements, etcetera, for the same object. I much prefer however to use brine
from which the impurities have been entirely or partially eliminated for all classes
of pans or heating apparatus heated by steam or with a low heat. A trough dis
provided to trap the small crystals and also to spread out the current the full width
of the pan.
e is a scraper to lessen the amount of turning required. It and the
other scrapers used for this class of scraping are preferably arranged with bearings
on the under side, and kept up to their work by suitable short levers and
weights.
Figs. 69, 70, end and side view of a system of heating a pan with a double row
of parallel pipes A at one end of the pan B. They are arranged in double rows to
occupy less space in the pan. The pipes are arranged across the whole width of a
narrow pan or in two or more sets for a wide one, as shewn in the Drawing.
They are preferably turned up smooth and parallel from end to end except where
the necessary flanges occur for bolting them to the steam cases a at the sides and
at ax at the centre. I preferably admit the steam to the centre case, and some-
times incline the pipes to a slightly lower level at the sides to let the condensed
water run through them freely for removal from the end cases by suitable steam
traps and pipes. I sometimes arrange them however to slightly slope down to the
centre with steam supplied at the sides, and the condensed water is then drained
off from the centre case. The pipes are provided with reciprocating frames C
and Cx which carry scrapers, preferably crossing and encircling the pipes in lines
at c; each set of scrapers traverses over a section of the pipes. The scrapers are
preferably made in parts, so as to be tightened up or replaced from time to time.
The frames with their scrapers have a short stroke to and fro actuated by the
movement of the levers D connected with them by rods at each side to joints at c¹.
The levers D are keyed on to a strong shaft d' and mounted on bearings on the
framing d² or otherwise supported. At the end of the shaft there is a lever Dx
moved up and down by rod e passing through a short tube ex fastened to the
bottom of the pan. The rod is actuated by a crank el on the shaft of worm-
wheel E. This latter is turned by a worm ƒ driven by a little engine For
otherwise. There is a chamber G under the pan to get at the machinery
approached by the stairs g or otherwise. Below the pipes in the pan there is a
sloping trough H down which the scrapings may be raked by a curved tool
passing under the pipes and then be withdrawn from the end of the pan. I
prefer to cover the pipes by floating boards to lessen evaporation over them,
providing spaces in them for the levers and rods to pass through. I is the pipe
supplying cool brine to the pan by the perforated tube i placed across the end of
the pan. The steam cases are supported on masonry J at the sides, and at the
centre at Ix. The central case forms a firm stand for the frame d and is bedded
with a broad base at Jx. K are raised passages round the pan.
Figs. 71, 72, end and side view of an arrangement of heating pipes designed to
occupy very little heating surface space in the pan, and further arranged so that
the scrapings will either fall into a trough at the bottom or be carried into the
pan by the circulating current. A is the end of a pan supported by girders a or
otherwise; B, a steam case containing the parallel vertical tubes b, preferably
drilled smooth inside. The case is supported by angle pieces bx and pillars 6 1
or otherwise. On one side of the case, preferably the pan side c, there is a channel
for the lower stratum of brine to sink down. The brine deposits crystals carried

page_text: by the current in the trough D where there is a revolving screw Dx, whose shaft
passes through a stuffing box at one end and is turned by suitable machinery. It
is arranged to deliver its salt into a pocket for removal by hand, or by an elevator,
or otherwise. Down the centre of each tube there is a revolving shaft e carried in
bottom bearings 63 and removable top bearings 62. There are worm-wheels e 1 on
the tops of these shafts turned by worms e 2 on the shaft e 3 by the driving wheel E,
or I sometimes turn them by bevel wheels on two shafts intergeared at their ends.
These vertical revolving shafts carry scrapers, preferably spiral, and arranged to
keep the sides of the pipes constantly scraped, while interfering with the current
of brine as little as possible. When the scrapers and shafts become coated with
incrustations, I either use solvents or take them out of the case by removing
bearings 62, and while they are being soaked in water or otherwise cleaned put in
a fresh set and continue the work. F is a chamber to get at the bottom of the
apparatus. The cool brine passes down C and rises through the tubes & flowing
from their tops into the pan again, having acquired heat on its passage. The
steam case B is provided with suitable steam and water pipes, and a man hole is
provided in the screw trough D to get at the screw after the case has been drained
free from brine by a suitable pipe. I sometimes arrange a valve over C, so that
after partially lowering the brine in the pan the tubes may be filled with water or
solvents to soak off or remove the incrustations on the scrapers and shafts without
necessitating the brine in the pan being much lowered. When arranging this
apparatus with a high side and overflow divisions, as with K, Fig. 48, the pan can
remain full of brine while the scrapers are soaked in solvents.
Figs. 73 and 74 end and side view illustrates a system for keeping the vertical
pipes clean without the necessity of using constantly revolving or other scrapers
for each pipe. It also shews how the steam case B may be cased in with walls C
to give greater solidity and lessen radiation, and further be provided with a
flushing or screw pipe at its bottom D. The tube D also serves the purpose of
supplying brine to the tubes above, being suitably connected preferably with a
supply pipe from the further end of the pan. The space above it is fitted with
a man-hole at one end. The vertical pipes are bored out true and smooth inside
and placed parallel with one another. On the left side there is a raised rail e on
the end of the pan, while on the right there is a second rail ex raised above the
level of the brine by occasional supports from the upper framing or plates of the
steam case B. Along these rails, which extend beyond the end of the case and
preferably over the ends of several pans similarly arranged, there moves a drilling
carriage F driven by a turning shaft or an endless wire rope 9 passing round
wheel G. The carriage is preferably made self moving, so as to move from one
pan to another, or from one pair of pipes to the next. It is also provided with a
handle to adjust it exactly over any pair of tubes, and a locking catch to keep it
steady in position while drilling them out. The carriage is arranged with two side
guides 6 and a sliding cross head b 1, which is moved up and down by two long
screws 62, one placed near each end of the crosshead. The screws are turned by
bevel wheels or shaft 63 by shaft and handle 64. The crosshead carries the
revolving ends of the two slotted or feathered drill shafts 6 5, and is arranged to
move them up and down as it is itself so moved. The drill shafts are turned by
worm wheels 66, through the centres of which they pass. The wheels are
supported by the lower frame of the carriage in suitable bearings. On the ends of
the shafts there are edge tools which nearly fit the pipes at the centre, and are
sloped top and bottom. As they are slowly passed down the pipes they cut off the
lime and incrustations of each pair of pipes under treatment, and again refit them
for further heating. I sometimes arrange for the drills to be lowered and raised
by self acting mechanism on the carriage, otherwise the attendant winds them
down and up by hand. After one pair of tubes have been drilled out the machine
is passed on to the next, and so on, until the heating apparatus is again fitted for
work. Although I have illustrated one pair of drills on the carriage I sometimes
construct it with a single drill or several to suit different combinations of pipes or

page_text: other purposes.
In a less advantageous arrangement I sometimes employ a
reciprocal slotting tool or scraper for short tubes. The turnings which fall to the
bottom are flushed out or removed by a screw, endless scrapers, or otherwise. I
do not always build up the steam cases in the way illustrated, sometimes using
cases, as shewn in the preceding Figures, or otherwise providing suitable supports 5
for the rails and footing for the attendant, etcetera.
Figs. 75, 76, 77, end, side, and plan view of twin pans arranged with deep rows
of parallel pipes so as to occupy only a small area in the pan, and arranged so that
the workmen may get down in the space at the back of the pipes for their inspection
or repair. A and Ax are the ends of a pair or coupled or twin pans worked by the 1
same machinery which is placed between them under the central platform. B are
parallel steam pipes preferably turned smooth and true and bolted to vertical
cases 1 and 62 at the two ends, which are supported on suitable masonry; the
cases are supplied with steam by the curved pipe c from the central pipe C. Valves
and hand wheels are provided at cx. The condensed water is arranged to collect in 1
case 62 and to be drawn off by pipe d. E are rods for moving the scraper e to and
fro for a short distance along the pipes. The rods are supported in the centre at F,
and passed through tubes and stuffing box in cases 61 at the machinery end. The
four rods of each pair are attached to a sliding frame moving between the two pans.
Those on the left to a vertical frame G, those on the right to a similar frame Gx.
The two frames are connected together and slide on guides H at the bottom to keep
them steady. The frames are moved backwards and forwards by a crosshead g 1
(sliding in guides h), to the ends of which are coupled a pair of connecting rods i
actuated by the rocking levers j, connecting rods k and kx, and cranks and lx on
the shafts of the worm wheel L. This wheel is preferably turned by a small
engine M. N is the chamber containing the machinery, and n the stairs leading to
it. The scrapings from the pipes which fall to the bottom are removed by endless
scrapers O, are carried to the pocket of an elevator P, which delivers them preferably
to a strainer over the pan so that the brine may return to it. The brine is some-
times supplied to the heater from the near or far end of the pan or from elsewhere
by pipes or troughs. It is here shewn brought up by one or more troughs a under
the pans, which enter the chamber A1 near the top. Valves are sometimes pro-
vided to close the end of the trough a and to open spaces over A 1 when the heater
is arranged to draw its brine from the near end of the pan if so desired. The
chamber A 1 is made the length of the pipes and wide enough for a man to move
along, so that the pipes or scrapers may be inspected or repaired. The chamber is
entered at one end by a man hole or watertight door, and the division a 1 is made
to take down in pieces to get at the pipes. The elevator is driven by a belt q
from a wheel on the small shaft qx suitably carried in bearings which is driven by
bevel wheels q 1, which also turns the trough scraper drum, and is itself turned by
a chain or belt 92 from, a wheel q3 on the shaft of wheel L. R is the platform
between the pans, and one round the end of the pans is preferably also provided.
Figs. 78 and 79 side and end view of another arrangement of pipes for heating
brine in a pan, also arranged with reciprocating scrapers for cleaning the pipes.
They are here moved by endless wire ropes or chains stretched round wheels at the
sides of the pan provided for the purpose. A, end of pan; Ax, sloping trough for
the collection and removal of scrapings, etcetera. a is a partial division over which
the heated brine flows; B, the parallel pipes supported by steam cases b at each
end bedded on masonry; they are supplied with steam and freed from condensed
water, as previously described. The pipes are scraped by the reciprocating
scrapers c, c1, carried on a suitable frame and connected by bars cx at the sides and
sometimes also at the top and bottom to keep them true. The frame is drawn
alternately to each side of the pan by three chains dx attached to the bars cx frames
passing round wheels d and 1, each set of wheels being keyed to its own shaft
suitably supported in bearings. The wheels are preferably arranged with flat or
wooden sides, which can be kept clean by scrapers provided for the purpose. I
prefer to place them a little beyond the sides of the pan, which have curved

page_text: casings ax arranged for them to work in fitted with the necessary bearings and
scrapers, tightening arrangements, etcetera. The shaft of the wheel & 1 is supported
over the end of the pan, and turned by worm wheel D keyed to it. This is turned
by a worm e on a vertical shaft, which is turned either way by wheels e 1 in gear
with e 2 and e 3, which are connected with belt pulleys e 4 and e 5 driven by a belt f
from an engine F, or otherwise. When the scrapers reach the end of their traverse
on either side of the pan the machinery is arranged to reverse itself, and they
continue their work, for which rods and levers actuating the fork rod are provided.
The machinery of the coupled pans is driven by wheel ex and cross shaft g with
suitable bevel wheels, so that the scrapers of both pans are worked by the same
turning drums or engine. Suitable catch-boxes are provided for throwing out of
gear either pan should it be necessary to work one without the other. The brine
is brought up to the trough Ax by two trough h, hx, or otherwise. I is the usual
platform round the pans, which also serves for keeping open the air holes from the
perforated blowing pipes, which I preferably arrange at the sides of these and all
other open pans where a supply of warm air can be obtained for assisting
evaporation. The pans from Figs. 65 to 79 have been chiefly illustrated with side
walks for removing the salt by manual labour. I preferably arrange them with
side rails, and employ machinery for removing the salt from the pans, which in
some cases enables them to be placed closer together, and economises space. The
salt from the various pans illustrated is sometimes arranged to be withdrawn by
hand, but is preferably removed by suitable endless chain scrapers, removing
progressive largers, or special machinery placed on by travelling frames or carriages
which I term pan carriages, and which move along or across the pan. I arrange
wheels running on rails at each side or end of the pan a to support them, and
sometimes also in the centre or elsewhere in the pan to lend support to long
carriages. In some arrangements I incline the rails at one end or side of the pan
to raise the carriages above its level or arrange to transfer the carriage from one
pan to another on a long carriage running along the ends of the pans. The pan
carriages are preferably made self moving, after the style of travelling cranes, but
in some cases are arranged to be moved by chains or ropes attached to them which
are passed round or fastened to wheels or drums on one or more shafts at the ends
or sides of the pan. When the carriage is made self moving I prefer to place
toothed racks by the rails on each side of the pan, into which wheels on the
carriage gear. I arrange for the machinery on the carriage to be driven by an
endless rope revolving shaft or by one or more engines fastened on the carriage or
coupled thereto, actuated by air, gas, or steam, with suitable receivers, boilers,
etcetera, for the supply of motive power.
Figs. 80 to 92 illustrate combinations and arrangements of pans, and others
specially adapted for having the salt removed by machinery, with pan carriages
in operation; some are shown delivering their salt on to draining boards,
belts, or waggons, while others are arranged to empty it into stores or pass it to the
side or end of the pan for it to be filled into moulds, or for other purposes. I apply
any of these modes of delivering the salt to each style of pan carriage under
certain circumstances when it is suited for it, but generally prefer the arrangements
illustrated. When arranging for pans to be heated by steam or products of
combustion mixed with steam or other low heat under their bottoms, I prefer to
place them over one or more chambers into which steam or heat is passed, and from
which it is withdrawn or escapes by one or more openings near the bottom of the
chamber as previously explained. I arrange water joints at the edges of the pans,
and preferably supply them with purified lime to avoid their metal bottoms being
coated with lime scale. Arrangements of this description are shown in Figs. 80,
81, 82, and 83, where the pans are arranged over one another to economise space,
and are provided with machinery for removing their salt.
Figs. 80 and 81 are the end and side views of two pans, one placed over the
other; the lower one being preferably heated by a brine heater, and the upper one
by the waste steam from the lower one. A, A, upper pan, steam heated; B, and B×,

page_text: the lower pan; C, girder or beams supporting upper pan; D, a row of pillars under
girder; E, central wall between B and Bx ; F, F, air cover to top of pan supported
from the roof by rods f; fx, chimney withdrawing steam and air from under pan
cover; f', screw vane to improve draught over brine. The chimney is either
widened out at its base, or is fed by a case placed across the pan end communicating
with the space below the case by numerous holes, so as to keep the current of air
which is supplied by case Fx similarly arranged well spread out over the width of
the pan. G, cover to lower pans, sloped to carry off condensed water with sido
gutters at and gx; Gx, hot air supply case similarly arranged to Fx to spread
current of air over breadth of brine in lower pan; H and Hx, chain wheels on
each side of narrow pans B and Bx; each pair of wheels is preferably keyed to one
shaft, or if separately mounted, intergeared and turned with a cross shaft driven
by powerful machinery; I, the endless chains, ropes, or wires supported at intervals
by rollers ix passing round H and Hx on each side of the pan, and carrying
scrapers i. The scrapers are preferably of increasing depths from the first to last,
so arranged either by their ends resting on ledges at the side of the pan, or by
their having supports of various depths attached to them and moving on the
bottom of the pan on suitable bars or slides. The object in this arrangement
being to lighten the work of the scrapers and strain of the drains by removing
successive thin layers of salt instead of deep masses; I sometimes arrange the
scrapers at equal distances along the whole chamber, but for shallow depths of
salt I prefer to place them on one half of the chains only as shown, so that
after work they may be wound up out of the brine and be cleaned or steamed
above the cover; J is a trough into which the scrapers pass their salt;
j is an end division dipping below the level of the brine to prevent steam escaping
or cool air from entering the chamber; K and Kx are perforated pipes connected
with one another for supplying and withdrawing brine to create the current
in pan B, which is preferably connected with a brine heater; L are deep
partial divisions under the upper pan to retain the greatest heat under the
end of the upper pan, where the current of brine commences; M is the escape
conduit for the cooler portion of air or steam to Mx a channel to chimney. N is
a sloping end to upper pan up which the salt is pushed; Nx, a draining board;
O, a lifting end to cover F on shaft ox opened and shut by the pan carriage S,
noving lever o centered at o 1, and connected with o by lever o 2, rod o 3, and
lever o 4 on shaft ox. When the end o is down it is at a short distance from N,
and serves to keep the current of brine spread out in the pan before being with-
drawn at the sides of the pan at P, where there are openings placed at its back.
From these openings the brine is pumped back through the perforated pipe p× at
the other end of the pan to again circulate down it; Q and Q× are chain or wire
rope wheels driven backwards or forwards by suitable machinery; R, endless
chains or ropes passing on both sides of the upper pan, and supported at intervals
by rollers; S, the pan carriage spanning the pan and mounted on wheels s
running on rails placed on t, tx, at its sides, and moved to and fro by the chains R.
It is provided with a dipping scraper sx which pushes the salt along the pan and
up the incline N onto the inclined draining board Nx, where it is left to drain
untill the next charge of salt brought up by the carriage pushes it over the end,
preferably into a line of carriages U placed there for its removal. The scrapers
can be adjusted to move at higher or lower levels to remove progressive layers of
salt, as in the pan below. The action of the chains in dragging the carriage back
for a fresh load, lifts the scraper clear above the salt, as explained more fully
Figs. 93-4. This carriage may also be used for removing deep cuts of salt at each
traverse, moving a little further back each time for fresh salt to transfer untill the
pan is emptied. In some cases I employ floating rafts across the pan, with one or
more scrapers fixed on their under side, which I drag backwards and forwards to
level the salt in the pan, and for other purposes. To avoid the great waste of steam
and products of combustion escaping from under the covers of deep surface pans,
I arrange bottom heated pans either at their sides or ends, or, where room is of

page_text: importance, at some distance above them, providing in each instance one or more
chambers under the pan or pans where the steam and gases can give off most of
their heat to the brine above. These chambers I preferably arrange to be deep,
and generally hang several cross partial divisions from the pan downwards so as to
cause the hotter vapour or gases to remain most under the end of the upper pan
where the current of brine is introduced. I sometimes cover all or part of deep
surface pans in with wood, rendered fire proof by being prepared with phosphate
of ammonia. When using metal coverings I generally arrange a wooden air-case
over them to heat air for stoves, or for passing it over brine in evaporating pans.
I generally slope the covering to the air case to drain off condensed or other water
into side gutters, and provide it with divisions and valves so as only to pass air
over such portions of the pan as are being worked. I either exhaust or blow air
through the covers, preferably using fans or chimnies for the purpose. In some
cases I supply them with fresh air by air shafts to the top of the building with
a self turning mouth or funnel to catch the wind, as shown Figs. 172 and 177.
Figs. 82 and 83 are the side and end view of a convenient combination of a
surface pan fitted with an air case, above which is a chamber under a second pan
heated by the waste vapours. The salt from both pans is removed by machinery.
A, A, upper pan supported with suitable girders, and arranged with circulating
pipes for brine in top pan, and hot air supply, and cover, and chimney, as in last
Figure; also similarly arranged for passing salt over the end of the pan by
travelling carriage B. This carriage is specially fitted with scrapers b and bx (see
Figures 95-6), and arranged for scraping the salt on the bottom of the pan into
ridges c, with the object of permitting more heat to rise through the intervening
plates thus scraped to the brine above, and also for subjecting the salt when formed
into ridges more thoroughly to the action of the not fully saturated current of brine.
The carriage is driven by an endless wire rope stretched between X1 and X 2, and
supported at intervals on rollers. The wheel X 2 is turned by the belt drum X 3
and belt X 4, or otherwise; E, Ex, are deep surface heated pans emptied alternately
by doors at their end e; F and Fx, the covers to them, preferably of metal, placed
a short distance above the brine; G, a flue at the end of the pan admitting hot gases
from the boiler furnaces or elsewhere; g, the valves to shut them off from either half
of the pan; gx, the escape for the gases and steam from the pan produced by their
passage over the brine to the upper chamber H with heat. Into this chamber I also
pass the waste steam from the engine or elsewhere. A valve is provided at gx over
each half of the pau, and pendant division h 1, h 2, and h 3 are provided, like L in
last Figure, to retain the hottest gases under the end of the pan A above where
the brine is admitted; I is the escape for cooled gases which pass through numerous
holes i. This cross case is preferably placed at a low level in the chamber, and
is connected with a chimney or otherwise to draw off the cooled steam and gases;
J and Jx are air cases for heating large volumes of air to a useful temperature for
blowing over the pan above or for other purposes. Their upper surfaces ; and jx'
may be of wood, and are sloped to the sides to drain off liquid condensing from
above. The lower portion of the case is formed by the plates of the pan cover F,
which provide a large heated surface for the air to pass over as it travels through
the case. The air preferably blown into the cases by a perforated pipe L placed
across its end, and escapes by a somewhat similar arrangement connected to the
pipe j which communicates with the air case kc, to pass it over the brine, under
the cover l, and up the chimney M, as previously described. The passage N at
the end of the pans is covered in and supported by arches n; at the end of the
building o is a curved roof to the building with a row of rods Q to support the
cover of the upper pan. P is a salt store to receive the salt from the upper pan
over the ledge q. It is provided with a back p and floor px, which is raised so
that the salt may be easily loaded in waggons R. This arrangement of pans and
buildings is useful in saltworks where furnace gases or steam are wasted. I also
employ it or forms of it in various combinations, where brine heaters are used, to
economise the waste furnace or boiler gases and for other purposes. Although
j

page_text: The
the pans in the last Figures are shown placed over one another to economise
ground space, I frequently place them side by side or otherwise on the ground
floor, and connect their covers or chambers with suitable pipes or channels.
system of removing the salt over the ends of the pans, and also of keeping the
bottom of the pans largely scraped, is a system I often adopt for bottom heated
pans in various positions.
Fig. 84 is an end view of a panhouse and pan arranged with an air cover over
the greater part of the pan for increasing evaporation, and so arranged that a pan
carriage moving beneath it can transfer the salt to one side of the pan beyond the
cover, which is left open so that moulds may be filled in it, and for other purposes.
The pan is preferably arranged with a cover extending sideways from d to dx.
A, A, is the pan; B, B, the walls of the building supporting the roof; C, C, is the
pan carriage for transferring the salt fitted with inclined scrapers c (see Figs. 97
to 99). It is arranged to pass a ridge of salt to the side of the pan at each back-
ward and forward traverse. D is the cover to the pan for causing the draught of
hot air lengthwise over the brine. It extends from d to dx; d 1 is a division from
the air case dipping into the brine to keep the hot air and steam in the case; e are
the rails on the left of the pan, and ex their support; f, the rails on the right
of the pan, supported at intervals by uprights fx, and arranged so that the salt
can be passed under them; G is the part of the pan beyond the cover which is
left open, and into which the salt is passed by the inclined scrapers c, as the
carriage moves to and fro; H is a passage for the operative to fill the moulds or
remove the salt. A waggon I, running on suitable rails, is provided for removing
blocks, salt, or moulds; X is the endless wire rope for driving the carriage, as
explained hereafter; x, one of a row of carrying wheels for supporting the endless
rope.
Fig. 85 is the end view of a pan house and pans placed over deep chambers
with water joints at their edges, into which hot gases, vapours, or both are passed
for heating brine above. They are arranged with travelling pan carriages, which
remove their salt over the two sides of each pan on to draining boards, and
afterwards transfer it into waggons or stores arranged between the pans.
Figs. 86, 87, and 88, plan view of the class of scrapers employed for removing
the salt. A1, A2, A3, are pans similarly mounted and placed side by side; a,
sloping sides to them; ax, hot air pipe; B are inclined draining boards on which
the salt is delivered; C, brine gutters; E1 and E2, salt stores; F, floor to same,
with sloping bottom draining into f and fx; G, walls supporting pan; gx, girders;
H, a row of central pillars in I under pan; I, chambers under pans, preferably
for the reception of steam and waste heat from surface pans or other source;
i, position of water joints at sides to keep vapour under the pans from escaping;
ix, sloping bottom of chamber for condensed water to drain into gutters i at the
sides; J, rows of strong pillars carrying the roof by upper pillars j, and the
beams K under the carriage rails kx; L are tie pieces bolted to sides of the pillars
at jx to the ends of pan girder gx at g1 to give the structure strength and keep
the carriage rails parallel; Kx is the suppot for the central pan rail k 2; M,
travelling pan carriages moving on rails kx and 2 placed at the side and
middle of pan. It is fitted with self acting swinging inclined scrapers m,
which move the salt in progressive ridges ax to the side of the pan, and pass
it up the slopes a above the level of brine on the pan, and empty it on
to draining boards B on each side of the pan at each forward traverse of the
carriage. On the return traverse it moves the salt off B into the store E1
and E2 below. The carriage is drawn to and fro by chains or ropes, as shown
in Fig. 80, wheels being placed to carry them at 12 and 13. The plan of
carriage M is given Fig. 86. The carriage frame is preferably composed of two
girders m fitting into end sockets at the side of mx, the end frames mounted on
the travelling wheels n; m 1 is a support to the girders in the middle and rides on
wheel nx.
The parts of the frame are strongly bolted together and tied by rods o
to give it strength and keep it square. It carries the sets of inclined scrapers, one

page_text: for each side of the pan; each set is composed of scrapers p, q, r, see Fig. 87, carried
in strong vertical bearings on the carriage frame px, qx, and rx. The other end
of scrapers p are further supported by a bar m 2 bolted to the girder m on the
under side, and provided with short circular rails m 3, on which a roller from the
end of each scraper runs to carry its weight. The scrapers on each side are tied
together by connecting rods p 1; scrapers 9 are longer than p and are shaped to
suit the slope of the pan sides, and pass the salt over its edge. Scrapers r are
made with dipping board r at their bottom to suit the slope of B. The position
of the scrapers for the forward traverse of the carriage is shown Figs. 86 and 87,
where the scrapers p are moving the salt in ridges to the side of the pan, and
scraper q is passing previous ridges over the side of the pan onto B, while scrapers r
are straight. In Fig. 88 the carriage is moving backwards; p and q are turned
straight to pass easily down the pan between the ridges, and scraper is moving
the salt from B into the store below. The scrapers are moved by the following
connections:x, x, are the side chains moving carriage to and fro fastened to the
ends of the two levers S, each moving a short way between stops and turning
the scrapers. Their ends inove between stops on the frame m so as to cause
the carriage to travel either way after the scrapers have been turned in the right
direction. The two levers S are connected by rod s and cranks 8×, so as to move
together and keep the carriage true on the rails. The scrapers p are moved by the
shaft of the lever S and connecting rod p 1; the scrapers 9 by lever q 1 and rod q 2
connected with S; the scrapers by connecting rod r1 between the tops of r
and q.
Fig. 89 is the end view of half a panhouse and pan fitted with an air case with
hot air blown over the brine from the side of the pan. This pan is arranged for
having its salt removed into an endless belt outside the pan and moving parallel
with it, by a pan carriage fitted with a revolving screw or other means for
transferring the salt to the side of the pan, and arranged for passing it over the
edge by an elevator or otherwise; A, A, is the pan; Ax a shallow trough along its
side; B, wall of building; C, one of a row of central pillars supporting the roof;
D, the cover to the pan supported on the left by chains or otherwise from the roof
rods or beams d; dx, trap doors to get at machinery on the carriage; d 1, light
division to conduct steam from pan to opening e in roof; F, perforated pipe
blowing hot air under cover over brine; G, travelling pan carriage, see Figs. 100
to 105, fitted with a revolving screw Gx, elevator g, and hopper gx; g 1, central
wheel and frame for supporting a wide carriage and long screw; H, endless belt
on which salt is placed by carriage; I and Ix, walls supporting rails for carriage;
X, wire rope for driving carriage.
Fig. 90 is the end view of a pan house and pan arranged with an air case and
travelling pan carriage fitted with endless scrapers, transferring salt into a long
trough at the side of the pan, along which it is moved to the end or elsewhere in
the pan by endless scrapers or belt, and transferred to the outside by an elevator
or otherwise; A, A, pan; Ax, deep trough fitted with endless scrapers or belt, see
Figs. 155-8; B, walls of building; C, pan carriage (see Fig. 106); c, endless
5 scrapers passing salt into trough Ax as the carriage moves down the pan; D, air
cover to pan hung from roof at d, d; dx, trap door to get at the machinery.
Fig. 91 is an end view of a pan house with twin pans whose salt is being
drawn by travelling carriages and emptied into waggon and store; A, A, walls of
building; Ax, masonry supporting rail beam; B, one of a row of central pillars;
Bx, side pillars supporting centrail rail beams cx; C and Cx, rail beams on each
of which plain and rack rails are bolted, and set parallel for the carriages to move
on. It is important that all pan carriage rails should be laid parallel with the
bottom of the pan as well as with their sides, so that the scrapers carried by the
carriages may move close to the bottom of the pan without touching it unless
arranged to do so; D and Dx left and right pan; d and dx, sloping sides;
d1 and d 2, air pipes; E, wagon way; Ex, waggon; F, brine trough arranged to
receive drainings from carriage; G, store place for salt with drain at 9; F and F×,

page_text: The
pan carriages (see Fig. 112); F is driven by a wire rope wheel X, and Fx by an
engine Y, boiler Z, or by gas, steam, or compressed air, or otherwise.
endless chain of buckets f moving in guides fx and carried by the carriage pass
round the wheels f 1 and f2, and charge themselves with salt moving outwards.
They raise it round the end wheel f1, drain it in perforated buckets on its way to
the top of larger wheel f2, and tip it over the sides of the pan down a shoot f3
into the waggon or store; Gx is a raised part on the roof to let the smoke out if
carriage is driven by a coal boiler on the carriage. I prefer however to use gas or
compressed air engines on the carriage provided with suitable receptacles for
containing a sufficient charge of gas or air to take the carriage well down the pan
and back again. In some cases I employ a flexible tube (see Fig. 153), for
supplying the engine with compressed air, preferably keeping the tube cool in a
trough of water arranged under the carriage, as explained hereafter.
Fig. 92 is an end view of a pair of coupled carriages for dredging the salt out of
two pans down which they are moving. They are arranged in a suitable building
covering the two pans, and empty their salt on to an endless belt placed between
them, which conveys it to a store house or elsewhere. A, A, are the walls of the
building; B, the walls of the central passage; C, the beans to carry the rails and
racks for the pan carriages; D, a footway between the two pans, at the side of
which there is an endless belt E. There are top and bottom rollers e and ex
provided for the belt, and pulleys x 1 and x 2 for the driving rope X; F and Fx
are the pans placed parallel with one another and on the same level; G is a pipe
for returning the brine from the further end of the pans to a brine heater, and
thence back to the pans to cause the current down them, as previously explained;
H and Hx are two pan carriages coupled together, the machinery for driving
which is shown on an enlarged scale, Figs. 143 to 146. They are each provided
with three chain drums h1, h2, h3, round which the chains for the buckets h pass.
There are guides and rollers hx for supporting the chains and keeping the buckets
from touching the bottom of the pan. The buckets are arranged with perforated
bottoms for draining the salt as it is moved over the pans. They move from 1 to
2 charging themselves with salt, pass up the incline, where they drain off the
surplus brine, to h 3, and empty it into hoppers h4 and h 4x. The hopper h 4
supplies the endless belt E direct, while the hopper h 4x supplies the belt E through
the medium of a short cross belt h 5. The pan carriages are arranged to stop
themselves at each end of their traverse, and a handle 3 is provided for causing
them to travel up or down the pans. Arrangements are also provided for regulating
the speed at which they travel so as to vary the speed of traverse according to
whether more or less salt is deposited. When using this class of apparatus for very
long pans (such as illustrated in Fig. 11) I sometimes dispense with the endless
belt E for removing the salt or drive the carriage by steam, gas, or otherwise, in
this way leaving room for a line of railway or other waggons to be run along the
sunken passage between the pans and filled direct by the pan carriages, which are
then preferably provided with a small centrifugal drying machine to throw off the
surplus moisture before the salt is loaded into the waggons.
Figs. 93 to 152 illustrate a variety of pan carriages and details, some
of which have been shewn on a small scale in the previous Figures. They are
chiefly arranged for moving under the air covers F of the pans P, as previously
illustrated, with their machinery kept low down on the carriages for the purpose
of passing under the covers which are placed as near the brine as possible. When
not using covers to the pans I generally place the machinery more on the carriage
than within it, and use vertical driving wheels in preference to those placed
borizontally. In some cases the machinery end of the carriage is only drawn in
the following Figures, as the complete apparatus has been shown in the smaller
Drawings, and the other end not illustrated is mounted on similar wheels to those
shown and supported by suitable framing. They are all common in the respect
that they span the whole or part of a pan, and are mounted on wheels at each end
of a carriage running on suitable rails. They are either drawn by chains, ropes of

page_text: wire, or other material, or are made self-moving, and are provided with tooth
wheels on the carriage intergearing with racks on the side of the rails. The rails
and racks are well supported either on wood or masonry, or both, at the sides of
the pan, or by metal framing in the pan when the pass over the brine. In some
cases the rails are arranged at the bottom of the pan to lend support at the centre
or elsewhere of very wide carriages. The rails extend the whole length of the pan
and are sometimes inclined at one end of it, so that the carriages after passing
down its length may be passed up the incline for the inspection or repairs of the
machinery, or in some instances for being passed on to a long carriage at the back
of the incline by which they may be transferred from one pan to another. The
rails in this set of Figures are marked r, the racks u, the supporting wall and beams
under the rails U, the pan P, and the cover F. In some instances where the
repetition of the same arrangement is obvious the lettering is omitted so as to
point out more clearly the different machinery on the carriages. The carriages
are arranged to move slowly along or across the pans and to manipulate the salt
therein, in some cases merely levelling it, but for the most part for removing it to
one side or delivering it over the side of a pan as they proceed. I arrange them
also for scraping and rubbing the bottom plates of a pan, for introducing fine, dry,
or damp salt into a pan, and for other purposes as they proceed. I construct the
frames or carriages upon which the machinery is placed of metal, wood, or other
material in a variety of forms and combinations. The arrangement I prefer is
shewn in Figs. 94, 96, and 101, plan views, in which there are end frames Z with
connecting girders Y fitting in sockets z, and preferably strengthened by side pieces =¹,
the whole being firmly bolted together. The girders are strengthened and steadied
at intervals by cross framing y bolted to the side girders, which also serves for
carrying bearings for long shafts placed along the carriage. In some cases the frames
are strengthened by tie rods yx or after the manner illustrated in other Drawings.
In some cases I also support the girders by under rods, as shewn Fig. 149. In place
of girders I sometimes use beams of wood, tubes of metal, lattice girders, or other
arrangements to form the frames and hold the ends together, arranging the frames
as light and strong as possible for the particular work the carriages have to do.
With a view of contrasting more clearly the different machinery for various
purposes mounted on the carriages, I have illustrated the carriages chiefly of one
type. The end frames, and sometimes one or more frames between the girders, and
mounted upon wheel x, which are arranged with suitable ledges or tyers. For
wide pans I frequently employ wheels at its centre, as illustrated Fig. 96.
For narrow pans I preferably only employ end wheels, sometimes adding one or
more low bevel wheels in the centre of the carriage, as shewn Fig. 100, running on
the bottom of the pan on a bar or rail, preferably let into the bottom, level with
its surface. When the carriages are made self-moving racks u, sec Fig. 96, are
preferably placed beside the rails on each side of the pan, and rack wheels wc,
Fig. 101, are mounted on the carriage, which intergear with them. The rack
wheels are preferably placed upon the same shaft and turned together or by wheels
at each end of the carriage, or are driven by a long shaft passing above them, or
at one side, on which there are small wheels gearing with the rack wheels, as
shewn Fig. 144, or on suitable wheels.placed at their sides. The object of causing
the two wheels to turn together on the same shaft wx, or by wheels on a con-
trolling shaft, like 2, is to insure that the carriage is always kept square and true
with the pan, and further, that it will advance and retire with regularity. Having
described the way in which I preferably mount the framing or carriages for
manipulating the salt and for other purposes, I will now proceed to describe the
various classes of machinery arranged to be carried by them. Figs. 93 and 94 are
the end and plan views of a simple style of pan carriage, already illustrated on a
small scale, Figs. 80 and 81. On the carriage are mounted two shafts A, B,
supported in suitable bearings on the end frames L and the intermediate framing y.
Beneath these is a frame composed of arms cx keyed to a frame, and fastened to
a scraper frame or board C reaching across the pan, in one or more parts. The

page_text: shaft c may also be in one or more parts, and is carried in bearings bolted to the
under side of the left girder Y. There are chains c 1 and c2 from the arms cx,
to the drums a and b, to which they are respectively fastened on the two shafts
A and B. The former lower and raise the scraper c, the latter support it at any
desired distance from the bottom of a pump for levelling the salt or other purposes.
There are two drums Ax on shaft A at its ends, which are turned to and fro by
the movement of drag chains or wire ropes D, or ropes of other material, by which
the carriage is drawn backwards and forwards along the pan, as shewn in Fig. 80.
These chains are either wound round the drums, or, preferably, pass under them,
resting on rollers carried on studs from the end frame Z. To each of these drag
chains I attach a short length of light chain fastened at its two ends to the drag
chain. It is wound round the drum Ax and fastened to it, arranged in such wise
that when the drag chains move either way they either wind up the scraper C or
let it down. There are stops on the drums, or, preferably, on the drag chains,
which allow the drums to be turned sufficiently for the above purpose, after which
they come in contact with strong stops on the end frames Z, and drag the carriage
to and fro. In this way the carriage is arranged to travel backwards down the
pan, with its scraper wound up and raised above the salt in the pan; but on the
drag chain being reversed by a suitable driving machinery, the scraper C is
quietly let down into the salt, and when the carriage starts on its forward journey
it pushes the charge of salt in front of it up the pan on to the draining board at
its end, as shewn in Figs. 80 and 83. Short cuts of salt may be moved pro-
gressively in this way, the carriage being caused to travel a little further
backwards each time, but preferably successive layers of salt are removed one
after the other by lowering the scraper a little more for each traverse. For this
purpose I arrange a worm wheel Bx on the end of the shaft B, which is turned by
a set screw b1 by a hand wheel or a moveable handle, or by mechanism in con-
nection with it. As the wheel is turned more or less it winds out more or less of
the chain c 2, and permits the scraper C to remove a lower layer of salt at each
forward movement of the carriage, and so on until all the desired amount of salt
has been removed. When using this apparatus to remove the salt from wooden
pans I preferably leave a thin layer of salt on the bottom of the pans, so that the
nucleus crystals falling up the surface of the brine may have a rough surface to
settle on. When using metal bottom pans with this class of apparatus, I pre-
ferably arrange their plates so as to form a level surface, as described in
Figs. 18, 19, and then scrape as much salt off them as the scraper C will remove.
For this purpose I preferably arrange at the bottom of scraper C to attach a row
of small separate inclined scrapers, which have a slight movement up and down
at their ends, and can follow the surface of the metal plates with greater
facility.
Figs. 95 and 96, end and plan view of a similar carriage illustrating the way in
which the connecting girders Y are supported at their centre by a cross wheel
frame yx into sockets y 1 on which they rest and are bolted. This carriage also
illustrates one method by which I cause the carriages to be driven by an endless
wire rope and to be self moving. The wire rope E passes round a grooved wheel G
keyed on a short vertical shaft g, on which there is a screw turning the worm
wheel W keyed to the shaft wx, at the ends of which are fastened the rack
wheels w, which gear in the racks u and cause the carriage to travel to and fro
along the pan. There are carrier pulleys or guide wheel e on the end frame,
to support the wire rope on each side of the wheel G, to keep it in proper position
for it, and also to raise and lower it on to wheels or rollers in the trough at
the side of the pan over which the wire rope travels, when not raised by the
guide wheels on the carriage. The machinery is kept low down so as to pass under
the air case F. In open pans I preferably place the grooved rope wheel G in a
vertical position and arrange for it to have a longer shaft. The same arrangement
as shown in these Figures is followed in modified forms with other pan carriages,
arranged to move under air cases and driven by wire ropes, as seen in Figs. 98, 99.

page_text: The carriage in Figs. 95, 96 is an enlarged view of the one shown in Figs. 82 and
83, and is arranged for forming the salt in the pan into ridges at repeated intervals,
and for scraping the metal plates between them. It is also arranged to remove the
salt from the pan in the same way as the previous apparatus, and is sometimes
employed for other purposes. It is fitted with a lifting scraper frame C in one or
more parts, and mounted as in the previous apparatus; it is however moved up and
down at regular intervals to scrape the bottom of the pan and from the ridges.
For this purpose I provide eccentrics or cams H on a shaft Hx. There are
chains c 3 fastened to the ends of levers I which are keyed to a shaft Ix turning
in bearings bolted to the carriage. There are rollers i which rest on the eccentrics
or cams H by which the levers and scrapers are actuated by the chains c3 being
attached to the arms c of the scrapers C. At the end of the cam shaft Hx there
is preferably an adjustable loose wheel h on whose back there is a worm wheel hx
keyed to the shaft. The wheels are arranged with a set screw h 1 to be mounted in
bearings on h, so that when the set screw is turned round the teeth of the two wheels
placed face to face assume a different position. This arrangement is provided to
turn the cams round a little so that they may lower the scraper C rather sooner or
later, for the purpose of scraping different portions of the pan bottom. The cam
shaft wx is driven by a small wheel w 1 gearing with wheel h; a clutch box is
provided on shaft wx actuated by a handle h 2, and starts and stops the movement
of the cam shaft, and may also be used for adjusting the position of the cams H.
The same arrangement as in the last Figure is also applied to this apparatus with a
similar shaft B, little drumus b and chains c 2 for regulating the depth to which
the scraper can sink. The worm wheel Bx on the shaft B is here turned by a
screw on the cross shaft b2 at the ends of which there are handles 63. On the
left of the carriage there is a scraper K in one or more parts the width of the pan.
It is supported on chains passing round drums k to which they are attached on the
shaft x which is turned by a worm wheel and handle or otherwise at the end of the
carriage, and wound up and down as required. There are chains c 1 from the front
girders of the carriage connected with a scraper, and it is used for the purpose of
scraping the extreme end of the pan on the left, and for other purposes. When the
carriage is in motion is moves the scraper up and down at regular intervals as it
proceeds, unless wound up by the handle 63. By this arrangement it scrapes short
lengths of the pan to enable them to impart more heat to the brine above, and form
the salt into ridges across the pan, through and over which the current of hot brine
passes. By driving the shaft Hx from the shaft wx, whose end wheels w gear
with the side racks u, the carriage may be allowed to travel backwards and
forwards several times, and a scraper C is raised and lowered the same way over
each ridge. By this arrangement the salt in the ridges gets less disturbed than it
would do if the scraper C were to move in an irregular manner. In order to
facilitate scraping the whole of the pan bottom at various times, the set screw h 1
is frequently turned which causes the ridges of salt to form a little further up or
down the pan as the case may be, causing the intermediate space between them
where former ridges may have been to be well scraped. After the ridges are
completed they are either left for further salt to accumulate on them, for which they
form a good base, or the carriage may be permitted to continue its work, and pass
the surplus salt up the slopes at the end of the pan to drain, as seen in Fig. 82, or
handle h 2 may be moved which stops the rising movement of the scraper C, which
can then be used to pass the salt in the ridges separately to the end of the pan,
or in progressive layers by means of handle 63, after the style of the carriage in
the last Figure.
Figs. 97, 98, and 99, end, plan, and side view of an enlarged scale of the
machinery end of the carriage shewn in Fig. 84 for ridging salt lengthways of the
pan, and passing it to one side. The lettering for the machinery in the Drawings
up to Fig. 103 is the same where the same movements are employed. Between
the girders Y there is a fitted a frame L which overlaps the girders on its two sides
and is firmly bolted to them. It has a series of frames or cross stays which cross

page_text: one another at Lx, and are also tied by forming 7x placed lengthways. It provides
strong top and bottom bearings at Lx for the scraper shafts m. The frame L
with its cross frames and supports to the row of central bearings Lx is preferably
cast or made in one or more pieces of suitable length firmly bolted together, and
is made strong and light and securely fastened to the side girders.
The scraper
shafts m have cranks mx at their tops, are firmly pinned or fastened to them, and
both support and turn the scrapers below. There is a connecting rod m 1 along
the row of cranks, causing them to move together. The lower ends of the scraper
shafts m pass nearly to the bottom of scrapers M, and are pinned or fastened
to their top bars n 2, by which they turn them. The ends of the bars m 2 are
turned up and come in contact with stops y 3 fastened to the under side of girders Y.
The scrapers M are preferably made of two thin sheets of metal fastened together
at the bottom and to the bars m 2 at their tops, slightly bulged at their middles
to allow the scraper shafts to pass between them, to which they are also fastened.
The scrapers should be light and strong, and made to resist lateral pressure. I
arrange various methods for turning the scrapers. The one here shewn is by a
quadrant m 3 fastened or forming part of the end crank in gear with the second
quadrant m 4 keyed to the shaft m 5, on which there is a strong pendent lever m 6
arranged, so that when it is moved backwards and forwards it turns the scrapers M
either way. The pan bottom is preferably sunk a little, where the scrapers are
set for their backward journey so as to let any salt that may have accumulated
between the scrapers fall clear from between them, as shown, Fig. 84.
The
lever m 6 has two projections or wheels near its bottom on the opposite sides,
which come into contact with a stop and inclined bar placed near each end of the
pan, or where the carriage ends its traverse. On the carriage nearing the end of
its journey one of these projections or wheels on the pendant lever is forced back-
wards by the stop, and travels up the inclined bar, lifting a catch near the top of
the incline, and gains a higher level. This turns the scrapers for their return
journey, when the carriage is reversed and returns along the pan. The stop or
wheel on lever m 6 passes over the catch it has previously moved from beneath,
and returns over it along a level bar arranged at its back so as to keep the scrapers
in their proper position for again moving the salt further to the side of the pan
during the backward traverse of the carriage. This bar ends before the other stop
or wheel meets with similar treatment at the other end of the pan, where the lever
again turns the scrapers in the same way, and returns back along a second bar
arranged with a catch like the one just described. From the scrapers being
swung in the centre they do not require much assistance to keep them in their
proper position, except when working in deep salt. In this case I use locking
bars or catches to hold them in position for each traverse, and sometimes employ
levers to move them after the style of levers s, Fig. 86, when the carriage may be
dragged by side chains as in Fig. 94. In some cases I arrange inclined scrapers
to pass the salt sideways, but instead of moving them partially round place them
on one or more bars, which raise and lower them at each end of the traverse. I
preferably use two bars of this description near together under the carriage, and
with their scrapers inclined in the opposite direction. The bars are swung on arms
carried on bearings from the side girders, and are connected by chains which pass
over wheels on a central shaft arranged so that one is let down whilst the other is
raised.
Figs. 100, 101, 102, 103, 104, and 105 are end, plan, side, and opposite end
views of another class of pan carriages, an enlarged view of the one shown, Fig. 89.
It is driven by a revolving shaft at the side of the pan like travelling cranes, and
also shows how I arrange to remove salt in a pan by thrusting a revolving screw
into it as the carriage proceeds, and then passing the salt over the side of the pan
by an elevator fixed on the carriage arranged to feed an endless belt at the side of
the pan; N is the turning shaft supported at intervals along the pan in the usual
manner and in the end of the carriage frame by brackets z 2. Between these
brackets, and turning on bearings in them, there is the short hollow axle of

page_text: This
wheel n, through which the turning shaft N passes and slides, but which turns it
in the usual manner by being square, slotted, or otherwise. Wheel is in gear
with Nx keyed to nx, the main driving shaft of the carriage. It turns a short
screw shaft n 3 by bevel wheels n 1, n 2, driving wheel W, and causing the
carriage to travel, as previously explained, by the wheels W on racks u.
variety of pan carriage is arranged with a revolving screw O carried in bearings
at each end by the framing z 3, well supported from behind, and by the central
frame y 4, which also helps to support the carriage by a wheel x running on the
bottom of the pan, or preferably a bar with sloping edges, or let in level with the
pan bottom. At the back of the screw there is preferably a curved plate O× with
a front scraper o resting on the pan bottom. The screw has at its end a
chain wheel o 1, which is turned by an endless chain o2 passing around a
second chain wheel o 3 on the shaft o 4. This is driven from the main shaft nx by
bevel wheels p, short shaft px, and bevel wheels p 1, or otherwise. There is a
handle P moving a clutch box p 2 to start and stop the screw turning. I sometimes
arrange a carriage after this style for removing salt in a store, as seen on a small
scale, Fig. 177. It is then preferably fitted with two screws like O, one on
each side, so as to remove heaps of salt on either side of it. I occasionally employ
two screws in a pan carriage so that it may remain alternately at the opposite
ends of the pan at each traverse, or for other purposes. I prefer with short pan
however to return the carriage to the incoming current end of the pan after it has
done its work, and to arrange for feeding the screw on both sides by either dispensing
with the curved back ox or by arranging to partially withdraw it, and substitute
one on the other side for the back journey. When the form of carriage drawn is
merely required to pass salt into a trough at the side of a pan, or on to a level
space, further principal movements than those thus far explained are not often
required. The Drawing however illustrates how the salt brought up to the side of
a pan by a screw or other arrangement can be removed over its side and fed on to
a travelling belt or waggon moving on the outer side. R is an elevator, see Fig. 103,
supported at the bottom by the frame 23, and fastened at the side to a frame
plate, or otherwise. It dips into a shallow trough p in the pan P, and empties its
salt by a shoot rx into the hopper Rx, which is also suitably bolted to the end pan
of the carriage. The chain drums of the elevator are driven by bevel wheels r 1
and the vertical shaft r 2, which is itself driven by the main shaft nx with suitable
bevel wheels. 3 is a handle to stop or start the elevator by moving a clutch box
on the main shaft or otherwise. The hopper Rx has a sloping bottom and curved
side, arranged to feed an endless belt S moving beneath it, which it supports at its
bottom by small rollers r 4 carried in bearings attached to the hopper. The rollers
in the hopper move over the rollers s 1 mounted at the side of the pan on occasional
supports 8x, on which the belt travels when not raised under the hopper. 82 are
the rollers for the return belt. There are short plates on each side of the hopper,
between which the belt moves. In this way the salt brought to the side of the
pan by the screw or other arrangements, as the carriage slowly advances, is
deposited into the trough px, or left where it may be taken up by the elevators
buckets, and emptied into the hopper which feeds the belt, by which it is removed
to where required. In some cases I dispense with the side trough p but prefer
using it when practicable. To carry off the brine mixed with the salt, and draining
through the hopper into the belt, I arrange a sloping ledges under the belt and
upper rollers 81, which conducts the brine into a side gutter placed above the level
of the brine in the pan, to which it is returned by short pipes through the wall.
When using elevators of this description in pans largely covered in with air cases F,
I arrange to suspend the latter at f by a chain from above, as shown, Fig. 102.
Trap doors in the cover are provided at fx to get at the machinery, and air is
preferably blown over the brine by a perforated pipe placed at Fx, extending along
the side of the pan. In some cases I arrange an elevator and hopper of the
description illustrated in the middle of a long carriage spanning a very wide pan,
and supported in its middle and elsewhere by suitable wheels and rails, preferably.

page_text: supported over the level of the brine. A central trough is then generally arranged
in the pan, supplied with salt by screws or otherwise on either side of the elevator.
The elevator removes the salt from the trough and empties it into a hopper on the
carriage, feeding a short endless belt, screw, or chain of scrapers moving over the
carriage, and suitably inclosed, supported, and driven. This belt carries the salt to
one end of the pan carriage, and either feeds the belt s at the side of the pan,
which should be placed rather lower for the purpose, or is arranged to fill waggons,
or empties the salt out at the side of the pan, or otherwise. In some cases, where it
is desirable to keep the whole of the machinery low down on the carriage so as to
cover the whole pan over with an air case, and employ a current of air from end
to end of the pan, or for other reasons, I replace the elevator by chains of endless
scrapers or by a short inclined endless belt Q, also preferably dipping in the
trough p, which is then made rather wider, see Figs. 104, 105, plan and side view.
In this arrangement the belt is carried by a large top drum q, and a little bottom
drum or roller qx, in front of which there is an inclined scraper q 1, up which salt
in the trough is forced by the movement of the carriage. The belt drums are
carried in bearings on two side bars q 2, which are supported at the lower end by
z3, a frame carrying the bearings for the screw O, and are suitably supported at
the upper end by projecting brackets z 4 from the end frame Z. The belt Q is
driven by the shaft of the upper drum q, being turned by bevel wheels 9 3, cross
shaft q4, and bevel wheels q5 in the end of the main shaft nx, or otherwise. The
belt delivers the salt into a trough q7, in which there is a short screw 78 supported
in bearings at 99. The screw is turned by a wheel at its end q 10 in gear with a
wheel 11 on the shaft of the upper belt drum, and empties the salt over the side
of the pan. By this arrangement the salt fed into the trough p by a screw o or
otherwise is carried up by the belt Q and emptied into the screw trough q7, from
which it is removed by the screw on to a belt S, or into a waggon, or otherwise. In
some cases I adapt this arrangement for removing the salt from wide troughs or
narrow pans, extending the endless belt Q across them in one or more parts, and
mounting it on long top and bottom drums or rollers suitably supported at the ends,
and also sometimes at intervals of their length. In this way I sometimes mount a
wide belt or belts in a separate carriage running on side rails, and arranged to
travel after the style of the preceding Figures, and driven in the same manner.
An arrangement of this description is useful for removing salt from a long trough
placed between two pans, into which the salt from the pans from either side is
passed by suitable machinery. Occasionally I employ a trough by the side of the
pan, into which the salt is suitably emptied and transferred by flushing it along
the trough with a rapid current of brine, produced by pumps on the pan carriage
or otherwise.
Figs. 106, 107, and 108, end, plan, and side view of a travelling pan carriage for
removing the salt sideways into a trough to one side of a pan or store, from which
it is removed by drag-scrapers or otherwise to the end or elsewhere in the pan or
store. This carriage has mounted upon it two chain or link drums A and Ax,
keyed to shafts a, and turned by wheels ax on their tops. The shafts are well
carried in bearings and framing B bolted to the side girders, or forming part of the
end framing. The drums are made light and strong, and preferably hollowed out
on the upper side, so that the frame bearings may be placed low down. They are
arranged with a sloping edge a 1, by which a scraper on the frame removes any
salt collecting on them. The upper side, and generally the lower side of the drums,
is made smooth, so that it may be kept clean by suitable scrapers and in
working order. At the sides of the two drums, and extending between and almost
touching them, are the side guide frames C (an enlarged sectional end view
of which is shown at D). The guides are used to ensure the scrapers moving
smoothly in case the bottom of the pan is uneven or liable to be injured by their
dragging over it. The guide bars c1 and c2 are well supported from above by
framing c and cx, which are bolted to the girders Y. They are also stayed from
the back by the cross framing c 3, which serves also to support a flat ledge c 4,

page_text: with a hinged sloping scraper c 5 at its side. The ledge is continued round the
bottom of drum Ax. In some cases I dispense with this ledge c 4 and c 5, letting
the endless scrapers mounted on the drum cut sideways into the face of salt
which they are removing, and occasionally let them scrape along the bottom of the
pan. I prefer using the ledge however, as when employing wooden pans or metal
pans with overlapping plates there is more certainty of the endless scrapers running
smoothly in case the guides wear loose. As the carriage moves forward the salt in
the pan is forced up into the ledge, and removed by the scrapers d which travel
along it. I arrange various forms of scrapers and links to drag them. They move
on and over this ledge with top and bottom projections on their links, which run
in the grooves of the guides c 1 and c 2. An end plan and side view of one variety
is shown at D, D 1, and D2, while that of another is shown at D3, D4, and D 5.
In both cases the scrapers d project sideways from the links, and are preferably
provided with a light back d 1. In some cases I let the bottom of the scrapers
travel on the ledge c 4, but prefer that they should move a short distance from it.
The scraper links are formed into an endless chain passing round the two drums
A and Ax, which are so arranged that they support the links while moving round
them, and drag the remaining links along the guides. A wheel z 5 carried on the
end frame Z runs along a rail r, a, on the side of wall Ux, and serves to keep the
carriage steady while the scrapers are running salt in the opposite direction. A
wheel for the same purpose is also shown in Fig. 101. The driving wheels ax of
the two drums A and Ax are driven in unison by wheels e on the same shaft E,
which is driven by the wire rope wheel G by a sloping shaft and intermediate
bevel wheels gx and ex. Bearing for the shaft g of the rope wheel G are arranged
outside the girders, so that they may be placed nearer together and be well over
the guides supporting the scrapers. A worm on the sloping shaft turns a wheel I
on a short shaft i and a small wheel ix on the same shaft in gear with wheel W on
the shaft wx, to which are fastened the rack wheels w for making the carriage
travel. There is a clutch box on the shaft E, moved by handle Ex, which stops
and starts the scraper drums. When the carriage is at work it slowly moves along
the pan, thereby forcing salt up the sloping plate c 5 on to the ledge c 4, where it
is removed by the continuous row of scrapers d, and brought round to the front of
the drum A over the edge of the trough p. As the scrapers circle round the
drum A the salt falls from between them into the trough, over which they hang,
and they continue their circuit until again coming round to the front ledge for
removing fresh salt. When using the variety of scrapers shown on enlarged scale
at D 3, 4, 5, or other scrapers arranged for working either way, I frequently remove
the salt both while the carriage travels forward, and also as it travels backwards.
In this way the carriage may be left at either end of the pan after it has removed
the salt from it, and when next started return to the other end, and again wait
until sufficient salt has again accumulated in the pan for its further employment.
I prefer however to return all the pan carriages to the end of the pan where the
current of brine enters, where they are more free from the accumulation of salt
amongst or against the scrapers. For this purpose the handle Ex is provided, so
that after the carriage has passed down a pan and done its work the drums may
be stopped, and the carriage run quickly back to the other end of the pan, where
it usually remains. I arrange various forms of troughs p for the salt to be passed
into by pan carriages. The deep one, illustrated in Fig. 108, is arranged so that
the endless scrapers t, s, or belts placed in it may be protected from the atmosphere
by both the upper and lower scrapers or belts being submerged. I employ several
varieties of scrapers and belts for receiving and removing the salt along the pan to
pockets placed in the pan or at its end, where elevators or other arrangements
remove it for further treatment. With very long pans I sometimes employ two or
more sets of belts or scrapers in the length of the pan, see Figs. 155 to 168. The
variety of scrapers shown is what I term "drag scrapers;" they are formed of
light metal links, with vertical end pieces or plates resting at their two ends on
slides p 1 and 2 on each side of the trough. The end pieces of the links are

page_text: connected by side pieces moving over the slides, and are sloped so as to enable salt
falling on them from above to pass through the links and lodge on the bottom of
the trough between the vertical end plates of the links below. These latter move
at a short distance from the bottom of the trough, and as they proceed push or
drag the salt along with them. In some cases I mount the links on little rollers
at their sides, but prefer to face the slides or the edges of the side pieces of the
scrapers with boxwood or other suitable material, which causes them to move more
easily, and preferably keeps lubricated by the brine in the pan. For very long
pans I sometimes employ two or more sets of endless scrapers and belts, passing
the salt on from one to another, as shewn, Fig. 163 to 168. The pan P is supported
by a wall p 3 at the side of the trough, and by a cross girder or beam p 4. It is
preferably covered in by an air case F, with its supports resting on the walls, and
provided with numerous trap doors to get at the machinery. As shown in the
smaller Drawings of pans, I frequently suspend chains from the roof or pan above
to assist in supporting it.
21
Figs. 109, 110, 111 illustrate another variety of pan carriage also arranged
for moving the salt in the pan to one side but in a way which causes less attrition
amongst the crystals with the object of better preserving their sharp angles, and
so assisting to preserve and deliver more perfect crystals for the production of
light salt."
On the bottom of the pan I place two long slanting scrapers A each
in one or more parts across the width of the pan. They scrape the pan bottom as
the carriage is moved to and fro and force salt up on one of these inclines on to a
travelling endless belt B (see B 1, enlarged and sectional view). The scrapers are
hinged or swung in bearings at a so as to follow the irregularity of the pan bottom,
or in some cases are fixed so that their lower ends move a short distance from it.
The scrapers are carried by a long frame C, supported by the frames c from above
and steadied lengthways by rods cx. The frame C carries numerous small rollers e
on which the lower belt B travels. The belt passes round a drum E by which it
is moved, and is kept tight by returning over the carriage on rollers el supported
in bearings on the frame y and passing round the end rollers Ex and E 1. The
latter roller is carried in bearings on the framing ex. The former is swung in
bearings on the sloping arm g, which are keyed to or form part of the cross
shaft gx mounted in bearings over the side girders Y. At the ends of gx there
are two levers g 1 to which are attached the weights G; these rise or fall with the
length of the endless belt and always keep it tightly stretched. The drum E is
keyed to a shaft e carried in bearings under the girders at its two ends. On the
shaft e 2 there is a chain wheel e 3 driven from a cross shaft hx by a similar chain
wheel h and the chain h 1 passed round both. The shaft hx is carried in bearings
from the end frame Z of the carriage; it is driven by bevel wheels h² by the ropo
wheel H, at its other end there is a second bevel wheel intergearing with two
loose wheels i and ix', which are made alternately to turn the sloping shaft I either
way by the movement of a clutch placed between them actuated by handle Ix.
The shaft I drives a cross shaft J by bevel wheels j; the latter has a screw on
it which turns the worm wheel W on shaft wx to which the rack wheels w are
keyed which cause the carriage to travel backwards and forwards. By moving
handle Ix the carriage is arranged to travel either way up or down the pan, or to
remain stationery as required. I sometimes apply this same method of reversing
the travelling movement of the carriage by wheels i and ix and handle Ix to the
other carriages, but preferably reverse the movement of the wire rope so as
better to insure the machinery on the carriage being re-started gently. Over the
lower belt B there is a scraper b which nearly touches the belt. It is suitably
supported at its sides, and slopes from the centre over the belt on each side, and is
arranged with curved plates which direct the salt delivered to it by the belt
moving towards it to leave the belt and fall into troughs p. In order to arrange
the belt nearer the bottom of the pan and so lessen the angle of the inclined
plates A up which the salt has to be pushed, I sometimes support the belt on
cross bars b, c, (see enlarged end view B 2) instead of rollers, as in B 1, and arrange

page_text: for them to slide in guides c placed lower down. Occasionally I place a drum,
like E, on each side of the pan in place of using the rollers Ex and E I, when drag-
scrapers, as previously described, may be used instead of a belt, suitable arrange-
ments being provided for their return over the carriage. When so doing I mount
the travelling scrapers t, 8, as shown at B 3, and connect the side guides by a
plate c, b, on the bottom of which the salt travels. This arrangement is useful
when the attrition of the crystals is not of much moment. On each end of the
carriage there are inclined scrapers K and K× the latter being an extension of b which
clear salt from the sides of the pan, and either deliver it to the belt, as on the case
with K, or into the trough p, as is the case with Kx. I frequently add scrapers
of this description or in other forms to scrape the sides of the pan where salt is
apt to cake near the surface of the brine. They are arranged to keep such portions
of the sides scraped, and also sometimes to rub the surfaces or carry wheels to prick
the air holes of perforated pipes placed at the sides of open pans to blow heated
air over them. The salt delivered into trough p is directed by two side plates p, b,
to fall on to an endless belt L which travels over a series of rollers l. Its return
belt travels over or under the pan as shown, Figs. 159-161, where it is preferably
passed through water to wash off salt encrusted on its surface. The mode in
which the belt delivers the salt is shown in the Figure just referred to. There are
suitable drums at the other end of the trough belt to return it to the pan from
below or above. The object of using single belts in the pan and passing the return
belt over or under it is that the trough can be made shallow, and the belt can be
well washed or repaired where it can easily be approached. The sides of the pan
are sloped with inclined boards or plates to avoid salt accumulating in corners
where scrapers might have difficulty in removing it. This is also arranged in
the pan for the carriage in the last Figure, and for other passes, when required.
Figs. 112 to 118 illustrate the machinery end of the pan carriage, shown on a
small scale, Fig. 91; Fig. 112, plan view; 113 Fig., side view; 114 Fig., end view
of part of machinery; Fig. 115, enlarged view of link wheels and guide case;
116 Fig, side view of guide case with top and bottom guides attached to it;
117 Fig., plan of links and bucket; 117a Fig., side view of links and bucket;
118 Fig., end view of links and buckets showing guides at middle of carriage. A is
the end frame of the carriage; B, girders or frames crossing pan and bolted to a
wheel frame at the other end, see Fig. 91; C, travelling wheels running on rail Cx
supporting carriage the same in each side of pan; D, rack wheel gearing with Dx
for making it move to and fro, connected with corresponding wheel on other side of
pans; E, frame bolted to girders; F, link wheels arranged with grooves f and flat
osides fx (see side) of carriage in the usual manner to clasp the links and turn
them with it. The wheels are keyed to shaft f1, which turns in bearings on frame E
and is driven by bevel wheel Fx. G, guide frame (see side) placed between link
wheels on shaft f1 and bolted to frame E at e (see side view, Fig. 116, and
sectional enlarged view of both together, Fig. 115). It has the upper and lower
guides Hand Hx bolted to it at g1 and gx. These guides cross the pan to a
similar case or one of less diameter placed between the other pair of link wheels,
see Fig. before referred to, and are supported mid-way by framing h and hx from
the girders B, as seen Fig. 118. I, link chains carrying buckets J, see Figure 117,
117, and 118. The are arranged with joints j and shoulders j 1 for projections on
the link wheels to catch and drag them by. j2 is a bar connecting the links under
the buckets J. It together with a lower projection jx serve to support or suspend
the buckets which are firmly rivetted or fastened to them. The buckets are raised
in this way to clear the guides round the end wheels. j3 are bars to connect the
links together; j4, wheels or projections which move in the guides and carry the
weight of the links and buckets. The buckets have curved ends to cut into the salt,
as seen Fig. 118; they are made round and sloping inside, so that the salt may be
easily discharged from them, and they have holes at their backs and bottoms to
drain the salt on its passage over the pan, so that it may be discharged
into the waggon with as little brine mixed with it as possible. These buckets

page_text: It is
discharge their salt into a moving shoot K, which slips it into the waggon
or other receptacles placed to receive it. K is mounted on a shaft k, and is
moved to and fro to let the buckets pass by crank kx, rod k 1, lever k 2, sup-
porting wheel k 3 running on cam wheel L at the back of Fx. M is the rope
wheel driven by the wire rope x, supported at intervals by wheels x 1.
keyed to a vertical shaft m, and turns bevel wheel driving cross shaft N by
bevel nx.
N has a worm n on it and two loose wheels n 1 and n 2. n turns a
screw wheel O on shaft o, turning wheels ol or o 2 according to the position of the
clutch between them, which is arranged to turn either moved by handle o 3. They
turn the driving shaft of the rack wheel D, and make the carriage travel either fast
or slowly by wheels d 1 or d 2 in gear with o1 and o2. The handle P moves a
clutch between n 1 or n 2 and causes one of them to turn shaft P, which is geared
with Fx at p 1, and communicates power to the link wheel and shoot K. According
to this arrangement the movement of wire rope x is reversed when the carriage is
sent on its backwards traverse, which contributes to the carriage and machinery
being started gently. I sometimes arrange to drive the wire rope only one way,
and provide reversing wheels to drive the carriage backwards and forwards instead
of the arrangement shown both for these and other pan carriages. The dotted
lines Q, Fig. 114, show the position of the engine and crank q illustrated in Fig. 91.
R is the waggon way and passage; Rx, the waggon for receiving the salt-from
shoot K. Its bottom r is sloped so that the brine in the salt drains through
openings on the left into trough S, which conveys it to a cistern and pump so as to
be returned to the pan. T is the masonry and wall supporting the rail beam U
and forming one wall of a building for a single pan. X is the wire rope for moving
the salt waggon Rx; X 1, a pulley for rope. With this same pan carriage with
means provided for travelling backwards and forwards along the pan and arranged
for driving the shaft f1 of the link wheels either way, I sometimes employ other
forms of link wheels and guides with suitable buckets or scrapers arranged for
passing the salt direct over the side of the pan without draining it on the top
chains. I prefer in this case to use link wheels on the carriage of equal diameter
on each side of the pan.
Figs. 119 to 122 illustrate one system I adopt for this style of direct delivery.
Figs. 119 and 120 show an enlarged top and side view of links A and buckets B.
The links have outside wheels b running in outside guides D. They are dragged
round suitable wheels keyed to the shaft f1, which have projections on them
pressing against bx the connecting bar of the links. The buckets are supported at
some distance from the links, as in Fig. 117 and 118; they have opening backs C
swung at the top of the buckets in bearings cx, and are opened and closed by the
movement of the curved connection c 1 carrying a small wheell or roller c 2.
Between the guides D there is fastened a bar or rail E which keeps the backs of
the buckets closed, in case too much salt gets forced up against them. This rail
continues round the circuit of the buckets, and is bolted at each end to a frame
(Ex, Figs. 121 and 122) fastened to the frame E at e, as previously explained. The
rail dips at e 1, to allow the roller c 2 to move backwards, thereby lowering the
back of bucket and shooting the salt out over a moveable flap F and fixed
shoot fx carried on the carriage into a waggon or stove. As the buckets travel
forward, E regains its former level at e 2, and the roller forces the back to again,
and assists in keeping it closed until it comes round again with a fresh charge of
salt to be delivered in the same fashion. In some arrangements of these pan
carriages I arrange to wash the buckets or scrapers as they travel over the apparatus.
For this purpose I cause them to pass over a long trough with high sides, and
shower or inject water over and into the buckets to scour them out. I arrange the
necessary pumps on the carriage and water supply in a channel outside the pan
when the operation of washing is carried on as the carriage travels. I prefer
however to wash the buckets at the end of the pan after it has finished its work.
For keeping clean the plates of steam or otherwise heated metal pans, I sometimes
add a small flat scraper 61 which has a slight movement only, and is jointed to the

page_text: bottom of the bucket. I sometimes also attach brushes or rubbing stones to one or
more of the buckets or scrapers to assist in keeping plates in working order, both
in this and other arrangements.
Figs. 123 to 127 show another arrangement for passing the salt direct over the
side of the pan; Figs. 123-4-5, end plan and side view of scrapers preferably
employed. A are the links with rollers a 1 placed outside them; they are arranged
with curved scrapers a with projecting curved ends ax to undercut the salt, each
link carries a light frame b jointed at bx, with a plate or board B fastened to it.
It is retained in the position shown, Figs. 125-126, by a short rod b1 with
pins or rollers 2 running in a narrow guide C, Fig. 127, under the large guide D.
These guides follow the course of the links, excepting at cx, where the bottom or
outer guide bows out in such wise as to cause the plates B to thrust out the salt
from each scraper as it passes by (see Fig. 126), and afterwards recovers its
previous position for the remainder of the circuit. Fig. 127 shows the way in
which I prefer to mount the frame of the guides C, D, on the girders B of the
carriage. F, F, is the link wheel; G, a curved plate travelling with the carriage
up which the salt is scraped; H, the shoot with movable flap I raised by the
scrapers, or by similar movements to those actuating K, Fig. 113.
Figs. 128 to 136 illustrate an arrangement by which pans with uneven bottoms
may be scraped, the scrapers dragging on the pan bottom in place of being
supported above it in guides. Figs. 128-9-30 are an end plan and side view of
the links and scrapers preferably used. Fig. 133 side, 134 plan, 135 side, 136 plan
of machinery for turning scrapers, etcetera. The links A carry projecting pieces a,
to which are attached pieces of thin metal b curved over at the top, and forming a
ledge C. The scrapers move along the bottom of the pan, and can rise and fall a
short distance between the flat side guide d and dx held in position at intervals
by the lower frames E bolted to the side girders; Figs. 131 and 2 show how
rollers fand fx placed on the lower frames E may be used in place of the flat
side guides d and dx to steady the course of the scraper links across a pan. When
using rollers for this purpose I prefer links with flat outer sides, as shown Fig. 132.
The scrapers are dragged forward round the link wheels N, Figs. 133-4, as before,
suitable projections being provided for the purpose. The salt is passed up a
curve G until hooked out and over the side of the pan by the action of a reciprocal
scraper or hook H moved to and fro by levers I on shaft i, actuated by rod j,
lever with wheel kx, weight e, and a suitable cam M on the side of link
wheel N. The hook has side projections h tracing up and down the sloping side
guides O, and the motion of the cam M is so regulated that the hook returns up
the slope of O, dragging the salt with it as it rises, and then permits the scraper to
pass by, when the hook again comes forward and repeats the process with the next
scraper full of salt. P is the side girder of the carriage Q, the framing carrying
the bearings ix and kx for the shaft of levers i and k; R is a curved case round
where the salt falls through its ends from the side guides O. Fig. 136 is a plan
view of the curve G bolted to the carriage up which the salt is raised by the
scrapers. The sloping sides g are arranged to clear the salt from the side of the
pan on each side of the pan as the carriage moves, and to force it under the
scrapers to be carried along the bottom or upwards; gx is a shoot to pass salt into
the waggon over the side of the pan. The link-wheels are mounted and driven as
previously described.
Fig. 137 to 142 illustrate the machinery end of a pan carriage arranged for
thrusting a wide frame of boards or metal plates extending across the pan in one
more parts under the accumulation of salt in a pan, so that it is forced on the
frame and afterwards lifted above the level of the brine to drain, and be removed
either from the sides of the pan or by the carriage travelling along the pan to its
end and slipping it off into a store or line of waggons. Figs. 137, end; 138, plan;
139, side; 140-1-2, details. A, wheel frame bolted to girders B, which are
encased in sockets a and held firm by projections ax bolted to the bottom of
girders C, carriage wheels D, rack wheel on shaft d; E, arms keyed to shaft e,

page_text: Fig. 140, supported by bearings 6 on girders B; ex, joint with framings under the
lifting bottom F, F, extending across the pan in one or more parts; fx, projecting
end bars of frame; f1, sloping end to bottom, up which the salt is pushed;
f2, rollers on frame; f3; and f4, chains to G; and Gx, the winding drums on
shafts g and gx carried in bearings h on frame H bolted to girders. Fig. 140 shows
the lifting bottom F on the bottom of pan being forced forwards by arms E under
a bed of salt. Fig. 141 shows F raised with its load of salt to pass over end of pan
by chains f3 and 4 being wound up on drums G and Gx. Fig. 142 shows
carriage over end of pan when the chains on drums G are kept tight, while
those on Gx are unwound there by sloping F and slipping off the salt off the
bottom in to a store or line of waggons at end of pan. The carriage is made to
travel, and the drums G and Gx are actuated as follows:-H is the rope wheel on
whose shaft there are two pair of loose bevel wheels I and K with clutch boxes
placed between each pair actuated by handles Ix and Kx and intermediate shafts.
They are arranged to drive shafts J and L either way by wheels at their ends
intergearing with Q, K. Shaft J has two worms j1 and 2 turning worm wheels
G 1 and Gx 1 on the shafts of g and gx for winding and unwinding the chains f3
and f4; clutch boxes are arranged to stop either worm turning. Shaft L turns a
wheel in gear with M, on whose shaft are keyed m and mx in gear with n and nx
running loose on shaft d, but arranged to turn it by clutch dx by moving
handle Dx. This latter is weighted, and has a short slip turn in the shaft so that
the weight may be moved over either side and the clutch kept up to its work by
the weight for thrusting F well under the salt in the pan, and a quick motion for
travelling to and fro from the end of the pan. To prevent over winding F a little
shaft o with two projections ol and o 2 moves a lever o 3 with a hook at its end.
This book holds up a weight ix on a lever attached to the shaft of the clutch box
in connection with the bevel wheels I. It is arranged that when either o1 or 02
is lifted by projections on the top of F, having been wound high enough, the
lever o 3 is drawn back and the weight ix falls and disengages the clutch at I,
thereby stopping the shaft I from turning. I sometimes arrange a separate motion
of this sort for each of the clutches, stopping the wheels gx and gx 1 independently,
so that when either side of F reaches the desired height the chains of its side
only are stopped. This arrangement of apparatus useful for removing salt
from the pan when it is desired to avoid unnecessary attrition among the
crystals.
Figs. 143-144-145-146, enlarged plan, side, end, and detail end views of
the machinery for driving the coupled pan carriages illustrated in Fig. 92. A are
the side girders spanning the pan and forming part of the side frames of the
carriages; Ax, cross girders or frames rivetted to A; B, the lattice girders placed
within the side girders and resting on Ax and steadied by supports ax to carry the
three drums C1, C2, and (C 3 not seen), the bottom and end guides D, and rollers or
slides for the return links; E is a wrought iron platform between the two carriages
rivetted or bolted to the girder frames A and Ax to keep the two carriages well
together. This platform is arranged for the superintendant to ride on when the
apparatus is in motion for moving the various handles, and is approached by
ladder e carried on the frame. When driving the apparatus by steam, gas, or
compressed air, etcetera, I place the engines, boiler, or necessary receivers on this
platform. F are the front wheels on which the carriages at the centre move along
rails G, they are fastened to the same shaft g to secure regularity of movement for
the machinery above; Fx, one of the back pair of wheels, also on a long shaft fx
to secure steadiness; Gx are the rack rails in the teeth of which the rack wheels H
gear. The wheels are fastened to the shaft g; there are similar racks and wheels
at the outer ends of the carriage. The beams I support the rails and racks, and
are secured to the frames J which bind the pair together by the ends j, and also
support bearings for the upper belt drum K and upper rope pulley Kx. L is a
passage for the attendant, with a side board 7; Lx is a passage under J to get at
the lower drums and pullies, over which the return belt and wire rope pass. The

page_text: beams I and the frames J are firmly supported by the walls Jx. M are the salt
buckets mounted on the chains Mx ; they are raised a little above the chains so as
to allow them to pass well round the chain drums and move along the guides D.
On the sides of the chains there are projections m which move in grooves in the
guides D and keep the buckets from touching the bottom of the pan so as to avoid
injuring it. I sometimes support the buckets and chains with rollers, or as
previously illustrated. N are the pockets or hoppers on the carriage into which
the buckets empty their salt; they have side pieces n to cover the guides round
the upper drum which commence at d, and also to allow the overhanging ends of
the buckets to pass. The salt from the left hopper falls down a shoot into the
belt O running under the left hopper and supported on rollers o carried by framing
from above. These rollers o raise the belt from the drums K and keep it level
while fed with salt through the opening nx. The salt from the right pocket or
hopper N is arranged to be transferred to the belt O by a short endless belt P
mounted on the drums P and Px which delivers the salt into the bottom of the
left hopper and causes it to pass under the arch nx which shapes it so as to keep
better on the belt for travelling. The belt P is driven by an endless chain px
passing round the wheel c, p, on the shaft of C, and the lower wheel p, c, on
the shaft of px ; C are the wheels driving the upper chain drums C1, on whose
shafts they are keyed. They are turned by wheels Cx on the shafts c driven by
bevel wheels Cx at their ends, in gear with smaller bevel wheels q, keyed to the
connecting shaft Q. Either of the drums can be started or stopped by moving
over the weighted lever qx which move clutches on c to or from the wheels cx, and
preferably drive them by friction. The weighted levers turn loose on their shaft q l
between stops on it, so as to swing well over to either side, and either keep the
clutch well in or out of gear or contact. The shaft Q is driven by wheel Qx in
gear with wheel r on the vertical shaft R, which is itself driven by a cross shaft sx
and bevel wheels rx. This latter shaft has at its end a wire rope wheel S for
driving the machinery. The wheel Q× turns loose on the connecting cross shaft Q,
and is made to turn it by a clutch box t moved into gear by handle T, and out of
gear by the weight Tx, both keyed to the short shaft tx." When the clutch is
pulled into gear, it remains so by the end of a pendant lever t¹, keyed to tx, passing
over the end of the small catch or arm u which rises behind it. The catch is keyed
to the shaft ux, on which there is the stopping handle U and a long weight u 2
supported by arms u 1, and also keyed on the shaft ux. Under the weight is a
pendant lever V proceeding from a cross shaft u carried in bearings on the two
side frames or otherwise. On the end of the cross shaft vunder the weight u 2
there are two short arms v1 and 2 turned up at the ends and kept steady by the
weight u 2 resting on them. The object of this arrangement is that when the
carriage has reached the end of its traverse either way, the bottom of the pendant
lever V comes in contact with a stop on 1, and as the machine proceeds, the
weight 2 is raised, lowering the catch u which liberates t¹, and allows the
weight Tx to move the clutch t out of gear and stop the machinery. For re-starting
it, either the stop on is removed, or the clutch t is held in position by the handle I
until the pendant lever V regains its vertical position. On the connecting shaft Q
there is a graduated belt-drum W, a belt w, from which turns the drum X, which
is mounted on a short shaft x, supported in bearings on uprights at each end. This
second drum drives the apparatus backwards and forwards at variable rates of
speed, according to the position occupied on the two drums by the driving
belt w connecting them. There are two loose bevel wheels 1 and 2, on the
shaft, on which there is a screw in gear with the worm wheel Yx. The handle Y is
mounted on a vertical shaft, and moves the clutch yx from one wheel to the other, or
stops both from turning, thereby regulating whether the apparatus moves either
way or remains stationery. The worm wheel Yx, is keyed to the shaft y 1, on the
end of which there is a small wheel y 2 driving a larger wheel Z; keyed to the long
shaft z which extends from the outer ends of both carriages and makes the carriage
travel by small wheels zx, keyed to its intergearing with the rack wheel H, or

page_text: otherwise, which move the carriage. I prefer to mount the various cross shaft
levers, etcetera, in bearings on frames, as shown, but sometimes vary the
arrangement. When driving the carriages by engines on the carriage, I preferably
employ one engine for driving the chain drums C, and another for causing the
carriage to travel; in this way the belts w, between W and X, may be dispensed
with, and the varying speed of the carriage be regulated with less trouble. When
driving the carriage with only a few changes of speed or at one uniform rate for
travelling, I sometimes place a shaft between the shafts Q and x, arranged with
suitable bevel wheels to drive the latter in place of the drums W and X. I generally
provide arrangements for enabling the carriage to move quietly down the pan
while dredging out the salt until it has finished its work and stopped at the end of
its traverse. I then reverse the travelling gear and alter it to a quicker motion,
stop the chains working, and run the carriage back again quickly to its starting
place, where it stops itself and remains until the next charge of salt has to be
withdrawn. When these carriages are used for very long pans, like Fig. 11, I
preferably let them remain at the alternate ends of the pans after finishing their
work. I not unfrequently apply the various motions illustrated in this arrangement
to other pan-carriages, causing them to stop themselves at the end of their
traverse or to travel at varying speeds. With the object of utilising the fine or
dust salt coming from sieves or grinding arrangements, and more especially that
produced by violent ebullition or by boiling brine under pressure, and afterwards
allowing it to evaporate when the pressure is withdrawn or reduced, or that
produced by evaporating one or more films of salt on heated surfaces fixed or
moving or produced in other suitable ways. I arrange to introduce the fine particles
of dry or wet salt into pans containing heated brine, and there subject them to
currents of fully saturated brine passing over and amongst them, thus placing them
in a position to acquire size and combine with other crystals and produce a larger
grain of salt for bagging or other purposes. An apparatus for facilitating this
object is illustrated, Fig. 147, 148, 149, 147a with end plan, side, and detail
views. The machinery end of the carriage is shown, the other end being similar
as regards supporting and moving wheels, hoppers, and air passages. A are
the hoppers, for salt extending along the greater part of the carriage, and
subdivided to give it strength and for other purposes. a is a balanced lid
swung at ax and balanced by levers and weights a 1. The hopper is preferably
filled at the end of the pan where the current of brine enters. The bottom of the
hopper slopes down to a long sliding grid valve B, see Fig. 147a, which is opened
or closed by connecting rods b, short levers 61 or the shaft 62 and a long lever 63
moved by a rod b4 on the end of which is a screw and hand wheel 6 5 which closes
or opens the valve and allows more or less salt to pass into the sieve C beneath.
This sieve is of sufficient length to receive all the salt let down from the bottom of
the hoppers. It preferably moves in slides c, c, on each side, or on suitable rollers,
or on swing levers or straps, and is rapidly drawn to and fro by a connecting
rod cx and crank D on the shaft Dx turned by bevel wheels d 1 and c1 on the
shaft Ex of the driving wheel E. These two shafts are carried on suitable
bearings on the frame F. There is a clutch box d 2 and handle d 3 to stop or start
the sieve moving and a fly wheel d4 to steady its motion. The salt passing
through the sieve passes down a contracted shoot G in to the air passage
nected with a row of long fan cases I. It is slightly curved at the bottom at g
and gx so as to protect the sieve from a back draught and incline the particles of
salt up the passage. The fans have boards or plates il and revolving arms ix
keyed to a long shaft Ix driven by wheel i 2 and the intermediate wheels j1
and j 2 by a wheel e 2 on the shaft of the driving or rope wheel E. J is a handle
moving a clutch box to stop or start the fans revolving. The fan shaft is carried
on suitable bearings at each end, and bearings kon each side of the cases I on
frames which also support the hoppers. These frames extend on each side of
the hoppers at k 1 and 2 and pass through the hopper division at k 3 and
below it at k and are firmly bolted to the side girders Y, which in their turn are
i con-

page_text: strengthened by rods y and supports yx previously referred to. The framing is
connected at the top by suitable bars and steadied at the ends by rods i 4. The
air for the fans is drawn from the two sides of the pan where it is more free
from steam by air channels L communicating with openings at the end of the fan
cases I. The salt falling from the sieves passes down G into the air channel i and
is blown from the ends of the channels over the hot brine in the pan in a finely
diffused and scattered state. There is a hinged flap m to close the end of the
channels when the machine is not at work, and it is preferably faced with cork so
as to make the closing more perfect. It is opened and shut by chains mx, levers m 1
keyed to a shaft M carried in suitable bearings and moved by a handle Mx. The
carriage is made to move by the rack wheels won shaft wx and worm wheel W
driven by a worm shaft N at whose end there is a bevel wheel intergearing with e 3
and e4 which turn loose on the shaft Ex, but either of which is caused to turn N
by the movement of a clutch actuated by handle Nx; P is the pan, and U the
wall or the support for the rail r and rack u over which the carriage travels by
wheels x and w; Ux is a platform at the side of pan. In some arrangements I
dispense with the fans at the back of the channel i and employ a finely perforated
pipe in their place connecting it with a fan at the end of the carriage or to a
flexible pipe joined to the carriage and supplying air under pressure. For certain
qualities of salt I dispense with the blowing arrangements and use revolving
discs under the hoppers to spread the salt over the pan, or sieve the salt
direct into the pan or down a sloping ledge placed under the sieve. In
another I dribble the salt out into the pans by valve B without using a sieve
or disc, and sometimes let it down in bulk into the pan and level it there,
preferably with a scraper attached to the carriage after the style of Figs. 93-4. I
prefer however to use discs or both the sieve and air blast to distribute the fine
particles over the pan in a more scattered state, so that they may have room to sink
and settle apart from one another and be better exposed to the brine current in the
pan. I sometimes employ one or more perforated pipes placed lengthwise over
the carriage, down which I force air with a small admixture of fine salt which
escapes through the holes and spreads over the pan. In this arrangement I place a
hopper at the end of the carriage into which I fill the fine salt and supply it to the
air tubes after the style of G, Fig. 147a. I employ a somewhat similar arrange-
ment for passing fine damp salt into the pan sometimes using a perforated trough
instead of perforated pipe or pipes, and flush the fine particles along it or them by
a copious supply of brine drawn from the side of the pan by a pump on the
carriage or otherwise. In order to insure the damp salt being well mixed with the
brine I also use a mixing tub on the carriage with revolving arms or stirrers in it
through which I pass the salt and brine on their way to the perforated pipes or
troughs. In a less advantageous arrangement instead of using carriages spanning
the pan in whole or in part I place the necessary hoppers and other apparatus on a
carriage moving at the side or end of the pan, or between two pans, and blow, eject,
or transfer with a flow of brine the fine particles of salt into the pan or pans at
their sides or ends. In some cases I place the hoppers, tubes, etcetera, over or at
the end of the pan where the current is introduced instead of using carriages to
move them along the pan or at its side.
Figs. 150, 151, and 152, illustrate the end, plan, and side view of the machinery
end of a pan carriage fitted with rubbing stones and brush for cleaning pan
bottoms (see Figs. 18 and 19), and for other purposes; A is the end fraine, to
which the girders B spanning the pan are bolted, with bearings for the travelling
wheels C, rack wheel D, and other parts of the machinery; E is a reciprocating
case of rubbing stones e or other grinding surfaces which rest on the bottom of the
pan P, and the case is caused to move to and fro and kept at position by levers e l
on shafts e 2, suitably supported by bearings on the right girders. A crank e 5,
keyed to the top of e2, is moved by a connecting rod e 4 by a crank pin on
wheel F; F has a short vertical shaft f, and is intergeared with loose wheel
gon
9x,
which is turned by wheel g 1, being in gear with loose wheels h and h1
shaft

page_text: on the shaft of the driving wheel H. A worm g 2 turns wheel D× on the end of
the shaft dx, and causes the carriage to travel; I is a revolving brush preferably
arranged to be lifted out of the pan, and, as far as practicable, made of a material
which is not injured by being left in the hot brine. It is preferably arranged
with spiral bristles or wires. It is mounted on moving arms J at each end of the
pan, which are keyed to shaft j, on which there is also a counter weight jx to
Jessen the power required to raise the brush to the position shown by dotted lines.
The brush is suspended when down by chains k 4, and wound up and down by
chains attached to drum K on shaft kx, suitably supported from the frame. It
is turned by a worm wheel and worm k2 on shaft k 3 by a wheel handle kx. The
object of raising the brush is to keep it out of the pan when boiling to save injury
to the bristles by excess of heat. The brush is driven by a chain wheel i on its
shaft, turned by a chain wheel yx running loose on the frame shaft ; and chain y;
yx is turned by a wheel on inclined shaft I, driven by bevel wheels h on the shaft
of the driving wheel H. There are handles d1, i 1, and Ex with clutch boxes to
stop and start the various parts of the apparatus. The rail and rack m, n, are
supported by wall O; P is the bottom of the pan, and Q the side trough to carry
off flushings; R, the platform at the side for attendant; X, the driving rope. In
some cases in place of using the brush I, I arrange for the stone case E to work
between divisions suspended from the carriages, forming a sort of trough and flush
water or brine down it from one end to wash out the rubbings at the other. For
this purpose I preferably use vertical levers to move the stone case, and place a
centrifugal pump on the carriage driven by its machinery. An arrangement of
this sort is useful for the pan A, illustrated in Fig. 10. When the stones and brush
are both used for long pans I prefer to incline one end of the pan, and also the
rails at its side, and arrange for the pan carriage to move up the incline and so
lift both the brush and the stones above the level of the brine in the pan. When
so doing I dispense with the arrangement for lifting the brush, and preferably use
two brushes, one on each side of the stone case, so as to brush the pan more
effectively. I sometimes adapt a moving frame of stones of the above description
to the back of the pan carriages arranged for removing salt from metal pans so as
to rub off any scale that may have collected on the pan bottom between the
intervals of the carriage's traverse. It is driven by suitable machinery in connec-
tion with moving shafts on the carriage. When employing several pan carriages
on the same works I prefer to use them one after the other so as to lessen the size
of the driving plant required. For this purpose I frequently employ a powerful
air compressor, and drive the various wire ropes, or turning shafts, trough scrapers,
or belts, elevators, etcetera, by small separate engines, or an engine for each pan or
pair of pans. When connecting flexible pipes to pan carriages for supplying them
with compressed air, I preferably place such pipes in a cold water trough arranged
near the side of the pan so as as to keep them cool in the hot atmosphere of the pan
room, and sometimes employ the same system in other hot rooms or places where
travelling machinery has to be driven, I either use short lengths of pipe connected
with a main pipe, and connect them with the pan carriage at intervals, or preferably
place one or more drums under the carriages in a long water trough, and pay out
and reel up a flexible tube as the carriage passes to and fro. A coil drum of this
description is shown.
Figs. 153 and 154, side and end view; A is the end of a pan carriage; ax wheels
on which it moves; a, rack wheel to move it: B is a supporting wall for rails b
and bx; C is a trough filled with cold water, and kept at the level indicated by
floats or otherwise; D is an inverted rack fastened to side of B; E is a frame
bolted to carriage A with suitable bearings supporting the hollow air drum F; fis
a stuffing box for the axle of the drum admitting air to pipe G which supplies air
to an engine driving machinery on the carriage or other purposes; H is a wheel of
the same diameter as the drum intergearing with rack D, arranged so as to turn
the drum and make it pay out or pick up the pipe without straining it; I is a
flexible air tube, one end attached to drum F, and the other supplied with

page_text: compressed air by an engine or otherwise. It is coiled round drum F and supplies
air for driving machinery on A by passing it through F and up pipe g. The tube is
kept cool by being submerged in the trough C although working in a hot room.
As the carriage moves to and fro the drum F is turned by the rack D and the
flexible pipe I is paid out along the bottom of the trough or picked up, and coils
upon the drum all the while supplying air to the apparatus. When a carriage has
to travel down a very long pan, and one drum will not hold a sufficient length of
flexible pipe, I employ two, preferably placed some distance apart with the coil
passed round the outer part of each. In some cases I employ a small moveable
boiler, engine and boiler, or gas engine and receiver, mounted on wheels and rails
which I move about from one pan to another, and couple on to each pan carriage
for its journey in succession. In this way several pans may have their salt drawn
in succession by one motor without the trouble and wear and tear of getting up
steam in separate boilers on the different carriages.
Figs. 155 to 162 show a variety or different delivery ends of pan trough, in
which endless belts and scrapers move, as previously illustrated in connection with
the pan carriages, etcetera; Figs. 155 and 156 are the side and end view, with a
chain drum for driving the endless chain scrapers, which deliver their salt into a
pocket at the end of the trough from which it is removed by an elevator; A the
pan; B, perforated air tube; C side wall; D, deep trough; E, endless chains with
cross bars e dragging the salt along the bottom of the trough which falls into the
pocket D, through the scraper bars on moving over the same; F is a chain wheel
keyed to shaft which passes through stuffing box a and is turned by wheel Fx.
g and gx top slides or wheels; g₁ and g² bottom ditto raising the scraper bars e a
little above the bottom of the trough D; G is the pocket at the end of the trough;
H, the elevator for removing salt. Figs. 157 and 158 are the side and end view
of a trough with a drum for driving a submerged belt which delivers its salt to a
pocket and elevator by which it is removed; A, end of pan; B, support; C deep
trough; D, elevator pocket; E, elevator; F, endless belt; G, belt drum driven by its
shaft passing through a stuffing box with H the driving wheel keyed to its outer
side; Figs. 159 to 162 illustrate arrangements I sometimes employ for washing
the return belt or chain of scrapers before they re-euter the pan by passing them
over or under the pan in a trough of water to remove the incrustation of salt, and
keep them in better working order; Figs. 159 and 160 are side and plan view of a
return belt, passing back over the top of an air case, and dipping into a water trough
to wash it. A the end of a plan; Ax, extension of trough; B, pan cover; C, shallow
trough; D, lower belt a little below bottom of pan and supported at intervals by
rollers; Dx, upper belt; E belt drum turned by wheel e in gear with f turned by
drum; F, the driving drum; G, a curved scraper placed at an angle over belt;
g, roller or rollers under scraper; H, sloping pocket; I, elevator; J, top scraper and
roller; Hx, washing trough for belt filled with water, which is preferably kept
running through it and regulated by floats and valves. Figs. 161 and 162 are the
side and plan view of a pan trough with the return belt passing under the pan,
arranged to dip into a water trough placed under instead of over the pan. The
Figures also illustrate means for raising the salt out of a pan trough without the
use of an elevator and the method of separate driving by a small engine for
turning the belt drums. A is the pan, showing part of the end; Ax, the extension
of trough; B, the shallow trough with sloping side b, as shown, Fig. 111; C, the
endless upper belt; Cx, the endless lower belt returning under pan, where there is
preferably a washing trough like Hx, Fig. 159; D is the belt drum placed outside
the pan driven by wheel d and mounted on frame E; F is the engine; f, a small
wheel turning d; G is the upper belt to keep the salt on the belt C and up the
The
steep slope and bring it out of the pan; H and Hx, the drums for the same.
drum Hx is turned by an inclined shaft dx and suitable bevel wheels driven from
the side of wheel d. I, weighted swinging scrapers to clean loose salt from the
belt. I sometimes employ a brush for the same purpose. J is the shoot for salt.
In some arrangements of pans I prefer having separate little engines for driving

page_text: the scrapers or belts in the troughs; in others I drive them by straps or gearing.
Occasionally I dispense with rollers along the trough and attach occasional scrapers
in the lower side of the belt to remove salt falling beneath it.
Figs. 163 to 168 illustrate the arrangements I employ for transferring the salt
in a trough from one endless belt or chain of scrapers to another, so as to pass salt
by two or more sets down a very long pan. I also arrange to collect it at one or
more places along the side of the pan for removal by screws or otherwise; I
preferably drive each double set of scrapers by suitably gearing their outer wheels
together, or by employing little engines, preferably driven by compressed air at
intervals along the pan. Figs. 163 and 164, side and plan view of a portion of the
middle of a long pan where two sets of endless scrapers bring up salt from the
opposite ends and empty it into a central pocket. A is the pan; B, the scraper
trough C and Cx, chains of drag scrapers; E, Ex, the chain wheels; F and Fx,
driving wheels; H, belt drum with small driving wheel h; I, a common pocket
sloping down to screw; J, screw to elevator K, shown in dots and placed beyond
the track of the pan carriage used for working the pan; 7, rails for pan carriage in
rack for ditto. Fig. 165 is the side view of an arrangement for using two sets of
drag scrapers to pass the salt along from end to end of a long pan or for other
purposes. A, the bottom of a pan; B, the trough; C, Cx, chain wheels turning
the same way;
D, Dx, chains of scrapers; E, raised ridge over which the scrapers D
pass the salt to scrapers Dx and so forward it down the pan. Figs. 166 and 167,
side and plan view of another arrangement for the same object. A, bottom of pan;
B, the trough; C, central pocket, from which salt is removed by hand at c, as
illustrated, but from which it may be flushed by arranging at its bottom cx a
suitable hopper and pipe with regulating valve, or by a screw, as in Fig. 163;
D and Dx, chain wheels; E and Ex, driving wheels with shafts passing through
stuffing boxes; F, driving drum; f, shaft; f1 and ƒ2, bevel wheels; G and Gx,
drag scrapers; H is a short endless belt to transfer the salt from one set of scrapers
to the next, preferably placed at a slight angle and mounted on rollers h, h1; hlis
driven by a shaft passing through a stuffing box at the side of the tank with
suitable gearing; I and J, the rails and rack for the pan carriage. Fig. 168 is the
side view of an arrangement for transferring salt from one trough belt to the next
for taking it down a long pan. A, the bottom of the pan; B, deep trough for
submerged belts; C, drum for belt Cx; D, drum for belt Dx, placed in a deeper
part of the trough and preferably sloping upwards to the previous level. I arrange
to wash the buckets and chains of elevators to free their surfaces from incrustation
of salt when dipping into hot brine or otherwise. I preferably apply the systein
of washing scrapers, buckets, belts, chains, etcetera, to all moving surfaces which are
liable to become encrusted by salt and rendered less useful in consequence.
Figs. 169 and 170 are the side and plan view of an arrangement for washing
the buckets and chains of elevators liable to become encrusted with salt by dipping
into hot brine or otherwise. A is the portion of an elevator case; a, ax, the back
and front of it; a 1, a long division forming the case in two or more long chambers;
B, elevator buckets rising to the top of elevator with salt; Bx, empty buckets
coming down having discharged their salt; C, washing case; c 1, sloping case to
catch washings; Cx, pipe to carry them off; c, cx, wider part at the side of case;
D, a perforated water, brine, or steampipe for washing the buckets; d, the supply
pipe; dx, cock; when steam is used a chimney is arranged to carry off the
vapour.
In large or extensive works, where various pumps, elevators, or other machinery
are scattered widely apart, I prefer to drive the same by water or compressed air
from an engine discharging its steam under a steam heated pan. When using
compressed air for driving the machinery the exhaust air from the various engines
is preferably used for feeding air cases over surface pans, or the heating tubes or
cases connected with pipes or cases for passing hot air over brine in pans, or for
blowing fine salt into pans, etcetera. arrange various combinations of the above
pans, and also pans and apparatus to bring the same into useful operation.

page_text: Figs. 171 to 177 illustrate a plant laid out so as to economise ground space
where this system of driving distant machinery by air is applied. The works are
arranged with preparatory and waste heat pans, etcetera, and means for facilitating
the manufacture of salt and delivering into waggons or boats. Fig. 171 ground
plan; 172, plan of upper floor; Fig. 173, side view of pans D Cx; Fig. 174, side
view of pans B and A; 175, end view showing brine heaters; 176, end view
showing section of pans; 177, end view showing store S. The works are laid out
with brine heaters, pans, apparatus and machinery previously described, and other
facilities for conducting the process of salt manufacture with economy and
advantages; A, Ax, are two long wooden pans preferably lined with thin sheet
Barff iron, having troughs a and scrapers or belts at their sides and heated
by brine heaters at their end; B, B×, are two metal pans placed over them heated
by the steam from the pans below, and preferably supplied with purified brine;
C, Cx, are two surface pans arranged for having their salt drawn alternately.
They are heated by the waste gases from the boiler furnaces by flue c or f2; D is
a pan placed over C and Cx, heated by steam and gases from below; F, the pre-
paratory pan for precipitating carbonate of lime in the brine. It is heated by the
waste furnace gases by upper flues fregulated by damper f1; f2, flue to surface
pans. The brine from this pan runs into tank G by pipe fx and feeds a filter Gx
and the brine heaters H, Hx, for pans A and Ax after the style of Fig. 57. They
are supplied with steam from boilers I, which like themselves are much below the
level of the ground to keep the pans A and Ax low down and lessen the height
of the building. The boilers are fitted with self-stokers and hoppers i, filled from
above by hand, or preferably by a screw j i, elevator j drawing its coal from J, a
coal chamber with sloping bottom filled by waggons running on rails za.
The
surface pans are covered with iron and an air heating case L for heating air, which
it receives from K by the self-adjusting mouth and channel Kx. The mouth K is
turned by a fan wheel k and suitable gearing, and the lower part of the
chamber Kx has a division and valve to stop back draught from the air case.
A and Ax are covered in with air cases with draining tops and side gutters, one
of which is shown at N, and are fed with air by cross channels and tubes n and nx,
The upper pans B, B×, and D have perforated air pipes at their sides. The warm
air from case L is exhausted by a perforated pipe m and pipe mx by a
fan M, which distributes the warm air to the various covers and pipes by
pipes m 1, m 2, and branches. The steam from pans A and Ax collected under
the two cases N escapes into the chamber above through openings in the
case at o 1 and o2 across the two pans, or may all escape at o 1 and finds its way
to the chimney Q by suitable cross channels at the end of O placed low down
to draw off the cooled vapour with the assistance of a fan or otherwise. Sloping
side boards ox are placed at the top of chambers O and Ox to keep the steam well
under the pans. The steam and gases from the surface pan rise into chamber Ox,
and are withdrawn from the lower end by a perforated cross channel p connected
with a fan and engine P, which preferably passes them to the left ends of the
chambers to assist in heating B and Bx, or may pass them direct to the
chimney Q. The pans are provided with pan carriages PC, to transfer their salt,
moving on rails at the side of the pans and suitably driven. Those used over
pan A and Ax are arranged to pass their salt into troughs a, from which it is
transferred by endless belts or scrapers ax, and passed by elevator al to the
centrifugal drier R. The carriages used for the upper pans pass their salt into
side belts b, bx, and d, at the side of which passages are provided for the
superintendant. The upper belts deliver their salt to the centrifugal drier R by
hoppers and belts dx ; R is placed sufficiently high to drain the brine coming
from the salt back into the pan, and delivers the salt by elevator r1 by a dis-
tributing disc, or to a belt r2 made to drive either way, which passes the salt into
the store S below; Sx is a gallery in the store supporting the drums for the
belt r2, along the side of which is moved a small carriage r 3 for distributing the
salt into different parts of the store. It is provided with rollers over which
Pans

page_text: the upper belt passes, and above these are inclined plates which pass the salt from
the belt over its side into the store below. By moving it from place to place the
different styles of salt made may be kept separate in the store; 81 is a back to
the store; 82, a raised bottom; s 3, a belt; 84, a passage; 8× is a travelling
store carriage moving to and fro to transfer salt from the store to the belt 83. It
is arranged after the style of carriages already described, and preferably fitted with
a revolving screw on each side for working backwards and forwards, and suitably
mounted and driven. The rails and racks for the carriage to move by are placed
above the floor, and the rack rail on the left is preferably placed sideways and under
cover to protect it from the salt above. The belt s 3 feeds an elevator 85 which
charges a weighing hopper 8 6. It is fitted with an opening bottom which discharges
its salt down a shoot 87 into a waggon z on the rails below, or into a boat if the
salt works are arranged for one to come up alongside. The salt from the surface
pan C, Cx, is emptied from passage T, which is provided with a bopper T and an
elevator tx to load waggons, or it may have rails through a door in the wall to load
above; U is a steam air compressor driven from the boiler, with which I preferably
drive the distant pumps and machinery at the further end of the works, arranging
suitable pipes, and connections for the purpose; V1 and V2 are pumps for circu-
lating the brine in pans A and Ax; V 3 and V 4, pumps for circulating the brine in
the upper pans; W is an engine for turning the scrapers of the brine heaters and
driving the wire ropes of the upper and lower pans, or they may be drawn by
separate little engines to each pan worked by steam or air; X, the outer walls of
the building; Y and Yx, upper and lower chamber for the brine heaters H and Hx.
The pans and machinery are suitably supported with pillars, girders, or otherwise.
The building is well lighted and arranged with convenient doorways, stair cases,
and passages. In some cases when ground is plentiful I lay works out on this
system as regards the ground floor, and place pans B, Bx, and D at the sides of the
other pans instead of over them, or if working A, Ax, at a low temperature I
dispense with the covers N and use perforated air tubes at the sides of the pans A
and Ax, working them with coupled travelling carriages, after the style of Fig. 92.
Works of this latter description are preferably covered over with light shedding
spanning each pair of pans so as to allow of the pan carriages to be coupled
together and dredge the salt from each pair of pans at the same traverse.
Z, Zx, are the upper and lower chambers of boiler house; z, grating to feed
hopper from above by waggon on rails a suitably supported from below; Z1, room
over boiler and pan house. When erecting new works I prefer to add all the
suitable improvements, and arrange various combinations of pans, apparatus, and
machinery to meet different requirements. When applying one or more of the
improvements to existing salt pans or works, many of which are old, and manu-
facturing salt in a very primitive manner, I often only select and adapt such of the
improvements as can be applied without unseating the pans or altering the general
arrangement of the works. In the foregoing illustrations and descriptions I have
shown how some of the various pans, apparatus, machinery, and other arrangements
may be usefully worked in combination, and in some cases be applied to existing
pans and plants for making salt by the ordinary process; by arranging a broad even
flow of brine over the furnace plates of pans, as explained, I greatly lessen the
deposition and accumulation of salt upon them, and to a large extent avoid panscale
forming over the plates where the greatest heat should be given to the brine above. By
reducing the degree of heat used under pans in the way described, and by increasing
its volume with steam or air, the chance of fusing salt to their bottoms is greatly
reduced, and much longer pans can be heated than those at present employed.
By causing a broad current or currents of brine to flow from end to end of pans,
the minute crystals forming on the surface of the brine at the hotter end of the
pan have time to grow and settle on a large and comparatively cool area beyond
the intense heat of the furnaces, when they have the opportunity of growing or
combining with other crystals, and preserving their natural angles. By employing
deep chambers under bottom heated pans, provided with water joints round their

page_text: "
edges, and hung with pendent partial divisions, as explained, and further by
admitting and withdrawing the heated vapours, gases, or both, from at or near
the bottom of the chamber, much heat that now escapes up the chimney is given
to the brine. By employing specially arranged self cleaning scaling pans, as
described, many impurities are eliminated from the brine with facility before it is
passed into other pans at a high temperature, a process which tends to preserve
the bottoms of the pans it supplies. By employing brine heaters in combination
with the broad current system in large evaporating or depositing vessels or pans,
the latter can frequently be made of wood at a considerable economy, while the
scale forming on the heating surfaces is confined to a small ground space, where
machinery, solvents, or acids can remove it with facility. By removing scale from
brine heaters by turning, drilling, or using other edge tools in different ways, I am
able to keep the heating surfaces in working order, and to evaporate brine con-
taining an excess of lime or other impurities which would otherwise soon render
them practically useless. By arranging to keep the heating surfaces in other
apparatus or pans constantly scraped or frequently rubbed, they are kept com-
paratively clean, and a lower heat can be used with greater effect. By using
purified or partially purified brine in brine heaters connected with evaporating
or depositing vessels or pans, and also in bottom or tube heated pans where steam
or low heat is employed, I largely or entirely avoid the formation of "lime scale
on their heating surfaces, thereby rendering them much more efficient, enabling
simpler apparatus to be employed, and largely recoup the cost of purifying the
brine by the improved quality of salt produced through the almost continuous
working of the pans, and the consequent increased production of salt. By
employing currents of air, preferably heated, over the surface of brine exposed
for evaporation, a less temperature may be used in the pans, and where air
cases are employed the steam rising from the brine (which usually escapes
into the air) is usefully employed for heating brine in other pans. By with-
drawing vitiated air from stoves and blowing it over the brine in adjoining pans
the ventilation of the stove and the evaporation of the brine is much facilitated
and improved. By using air cases over the covering of surface pans large volumes
of air are readily heated for facilitating evaporation in other pans, while the steam
and waste heat coming from the deep surface pans is also utilised for heating
brine elsewhere. By using the waste furnace gases from boilers for the above
purpose steam from the boilers may be supplied to the brine heaters with much
economy. By employing pan carriages and travelling arms for removing the salt
from long, circular, and other pans much labour is economised, time saved, and the
work is conducted with greater regularity. By scraping salt into ridges more
heat can rise through the pan bottom. By employing troughs with belts or
scrapers at the side or elsewhere in the pan salt can be removed with facility to
wherever required, while by the employment of waggon ways and salt stores
between the pans much time and trouble may be saved when the pans are worked
by hand. By the use of draining boards and centrifugal machines, as described,
the salt is rendered less liable to cake, and much valuable hot brine is passed back
again into the pan which is now frequently wasted. By employing travelling
belts and the other appliances for conveying salt from pans to a storehouse much
time and labour is saved, while travelling carriages used in the storehouse to
remove the salt tend to its being delivered with despatch. By arranging to wash
elevators, scrapers, belts, etcetera, moving in and out of brine or amongst damp
salt, I am enabled to keep them in working order, and with but little encrustation
on their surfaces. By arranging to flush all pipes or narrow channels through
which brine passes with water, steam, or solvents, as occasion may require, they
can be kept in a state of working order which might otherwise not be possible.
By employing wood, pre; ed with phosphate of ammonia to render it fire proof,
in the place of iron or brickwork, where suitable, lighter coverings may be used
for pans, hot air channels, and other purposes. The whole of the iron work iş

page_text: preferably protected from rust by being coated with black or magnetic oxide,
according to a well known process.
Having now described my Invention, which, as mentioned in my Provisional
Specification, is as it were an addendum or suppliment to my previous Patents,
Nos. 4324 of 1876, 1788 and 2106 of 1877, and 1336 of 1878, I wish it to be
understood that though in some of my Drawings and descriptions I may have for
convenience introduced small portions of my previously patented Inventions, in
order to more fully explain my present Invention, I make no claim under this
present Patent for such items, but that what I believe to be new and claim as my
Invention to be protected under Letters Patent is,―
First. In the manufacture of salt from brine, admitting and withdrawing the
brine at or near the opposite ends or sides of a pan in a number of small and
preferably equidistant equal streams, or in a broad thin flow, or its equivalent, so
as to cause a slow broad current or currents of brine to flow along or across pre-
ferably the whole width and length of a pan or pans, or across and along one or
more parts joined together in such wise that a large area of crystals in the pan or
pans is subjected to an even or more even current or currents than has hitherto
been obtainable, substantially as and for the purposes described.
Second. In the manufacture of salt from brine, causing the brine in circulating
pans to leave the pan in a broad current or currents, or number of smaller and
preferably equidistant currents opposite the end or side of a pan, where it enters
and receives the greatest heat, or enters at the greatest heat in such wise, that
quick currents may be passed over furnace plates, heating tubes, or surfaces in
connection with the pan to lessen the deposition of crystals thereon, while the salt
depositing in the pan or remainder of the pan is subjected to a slow or wide
current or currents, until it is returned and re-heated, by which means the heating
surfaces are kept cleaner and in better working order, while the growth or com-
bination of the crystals with one another is less disturbed, and is practically uniform
over the breadth of the pan.
Third. In the manufacture of salt from brine, circulating the brine in a broad
shallow current or currents, or circulating it in upper and lower currents, or
currents of different temperature in circular and other pans by means of jets,
machinery, pumps, or suitable inlet and outlet channels, in cases, pillars, or in a
division in the pan, or inlet and outlet channels communicating with the pan or
like apparatus, in combination with surfaces heated by steam or other medium to a
heat insufficient to fuse salt to said surfaces to any considerable extent, placed in
or connected with the pan, or its circulating channels arranged with scrapers,
rubbing surfaces, or stones, or cutting tools actuated by machinery, or with heating
surfaces arranged in alternate vessels or appliances, so that one part of them can
be cleaned with solvents, acids, or otherwise, while the alternate part is working,
substantially as and for the purposes described.
Fourth. In the manufacture of salt from brine, circulating the brine in divided
pans or pairs of pans in such wise, that it passes over heating surfaces twice or
more in its circuit, preferably at the opposite or alternate ends, substantially as
described.
Fifth. In combination with bottom heated salt pans, deep chambers below
provided with water joints round their edges, and with or without pendent partial
divisions, from which chambers the heated gases or vapours are withdrawn at or
near the bottom, substantially as and for the purposes described.
Sixth. In the manufacture of salt from brine in furnace or bottom heated pans,
brine heaters or table pans, mixing the products of combustion, substantially in the
manner described, with steam, air, or both, so as to greatly increase their volume,
and at the same time lower their heat to a point not sufficient to easily fuse the
salt and form pan scale.
Seventh. In the manufacture of salt from brine in evaporating pans, the mode of

page_text: levelling, ridging, or removing successive layers of salt, substantially as and for the
purposes described, especially in connection with Figs. 48, 80, and 82.
Eighth. In the manufacture of salt from brine, the employment of heated air
escaping from the perforated pipes or channels in broad currents or numerous
small jets over the surface of the pan to blow the steam off, substantially as
described.
Ninth. In the manufacture of salt from brine, introducing large quantities of fine
salt, such as that produced by film apparatus, surface pans, violent ebullition or
sieving into pans, for enabling the fine particles or crystals to increase in size or
combine with other particles or crystals, substantially as described.
Tenth. In the manufacture of salt from brine, the constant or periodic and
preferably automatic washing of elevators, travelling belts, scrapers, buckets, chains,
or other appliances used amongst damp salt or dipping into brine, in the manner
substantially as herein described, so as to remove the incrustations forming on their
surfaces while working, by which means they are prevented from choking up and
becoming less effective or useless.
Eleventh. The manufacture of well crystalized salt in pans of the ordinary large
area type heated below by products of combustion largely diluted with steam or air
or other heating medium, not hot enough to cause salt to line the bottom by
attaching itself to the heated surfaces, and from brine in which the calcium salts
have been previously percipitated by chemical means, by which combination the
precipitation of hard scale, always hitherto found when a low heat and slow
crystalization have been used in combination, is avoided.
Twelfth. The general arrangement, construction, and manufacture of machines,
plant, or apparatus for the manufacture of salt from brine, substantially as herein
described or shown in the accompanying Drawings, no claim being made for those
parts already described in my former Specifications above mentioned, nor for any
one part taken separately or used for a different purpose to that set forth in my
Specification, but only when combined with the other parts or their equivalents, so
as to make a complete single mechanism, substantially as described or represented
in any one or more of the numerous figures annexed hereto, and for the purposes
herein set forth.
In witness whereof, I, the said John Howard Worthington Biggs, have
hereunto set my hand and seal, this Sixteenth day of July, in the year of
our Lord One thousand eight hundred and eighty one.
JOHN HOWARD WORTHINGTON BIGGS. (L.S.)