CERTAIN IMPROVE- MENTS IN MANUFACTURING SALT, AND IN APPARATUS FOR MANUFACTURING SALT
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
ELLINS, of Droitwich, in the County of Worcester, Salt Manufacturer, send
greeting.
WHEREAS I did, by Petition, humbly represent unto Her present most
Excellent Majesty Queen Victoria, that I had invented "CERTAIN IMPROVE-
MENTS IN MANUFACTURING SALT, AND IN APPARATUS FOR MANUFACTURING SALT,"
and Her said Majesty, being willing to give encouragement to all arts and
inventions which may be for the public good, was graciously pleased, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of
Great Britain and Ireland, bearing date at Westminster, the Twenty-second
day of March, One thousand eight hundred and forty-eight, in the eleventh
year of Her reign, for Herself, Her heirs and successors, to give and grant
unto me, the said George Ellins, my executors, administrators, and assigns,
Her especial license, full power, sole privilege and authority, that I, or
they, by myself or themselves, or by my or their deputies, servants or agents,
or such others as I or they should agree with, and no others, during the
term of fourteen years from the date of the said Letters Patent, should and
lawfully might make, use, exercise, and vend my said Invention within that part
of Her said Majesty's Dominions called England, Her Dominion of Wales,
and Town of Berwick-upon-Tweed, in such manner as to me, my executors,
administrators, and assigns, shall seem meet, and that I or they shall enjoy
the whole profit and advantage arising by reason of the said Invention during
the said term of fourteen years; and whereas the said Letters Patent contain
a proviso obliging me, the said George Ellins, particularly to describe and
ascertain the nature of my said Invention, and in what manner the same is to

page_text: be performed, by an instrument in writing under my hand and seal, and to
cause the same to be enrolled in Her Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
Letters Patent, as in and by the same (reference being thereunto had) will
more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
George Ellins, do hereby declare that my said Invention is described and
ascertained in manner following, and by the aid of the three Sheets of
Drawings hereunto annexed, that is to say :-
Part of my improvements in manufacturing salt consists in the application
(in manner herein-after described) of a current or currents of heated air to
act beneath the bottom of a salt pan or the bottoms of salt pans (or beneath
portions of the bottom or bottoms of such pans) wherein the watery portion of
salt brine is to be evaporated, so as to cause the salt contained in that brine
to deposit in crystals of common salt within the salt pan, such current or
currents of heated air being atmospheric air, which, previously to being heated,
is forced by action of suitable blowing machinery through a system of iron pipes,
which are inclosed within a suitable stove or oven, so as to be kept strongly
heated by fire, and the flame, heated' smoke, or gas proceeding therefrom
applied within such stove or oven, so as to surround and act upon the exterior
surfaces of the said pipes, and heat the iron thereof, in order that the said
current or currents of air, may become heated in passing through the interiors
of the heated pipes, in like manner as similar currents of air are heated in
passing through the heated pipes of what is called a hot-blast stove or oven
belonging to a blast furnace for smelting iron by what is termed hot blast.
And, according to this part of my improvements, such currents of heated air
are to be conducted through suitable passages beneath the bottoms or portions
of the bottoms of salt pans containing hot brine, so as to act beneath those
bottoms (or beneath portions thereof), and communicate additional heat by a
very regular transmission thereof from the heated air upwards, through the
iron of the said bottoms or portions thereof to the said hot brine, in order to
cause a rapid evaporation of water therefrom, and consequently the deposition
of common salt in crystals within the pans. The said stove or oven, wherein
the system of air pipes is inclosed for the purpose of receiving heat from the
fire or fires within that stove or oven as aforesaid, is (according to this part of
my improvements) to be disposed beneath one end or part of a large salt pan
having a double bottom, with some fresh water contained in the enclosed
space that is included between the two bottoms, so that whilst the brine is
resting upon the uppermost the said fresh water will be resting upon the

page_text: lowermost of the two bottoms, but leaving a space between the upper surface
of that water and the uppermost bottom; part of the said lowermost bottom is
to extend over the whole area of the stove or oven, so as to form a flat roof or
top thereto, in order that the heat which is kept up by fire or fires within the
said stove or oven, for the purpose of giving heat to the said system of air
pipes, may also operate beneath the said lowermost bottom of the salt pan;
and by transmission upwards through the iron of that lowermost bottom to the
said fresh water which is resting thereon, the heat will cause that water to
boil and produce steam in the same manner as in a steam boiler, but that
steam will ascend in the aforesaid space above the water, and will act beneath
the uppermost bottom, and a transmission of heat will take place upwards
through the iron of that uppermost bottom to the brine that is resting thereon,
and the heat that is thus communicated from the steam will be distributed
with uniformity throughout the whole extent of the brine, so as to cause eva-
poration therefrom. The steam from which the heat is so communicated will, in
the act of communication, become condensed into minute drops of fresh water
beneath the under surface of the uppermost bottom, and those drops, as they
accumulate into larger drops, will fall down into the fresh water beneath,
ready to be again boiled therewith and raised into steam, which will act again
beneath the uppermost bottom in the same manner as before, and as already
explained, so as to keep up the said uniform distribution of heat throughout
the whole extent of the brine. The current of flame, heated smoke, gas, and
air proceeding from the fire or fires within the said stove or oven passes
onwards therefrom beneath the remaining part of the lowermost bottom of the
said salt pan, beyond that end or part. of the said bottom which (as already
mentioned) forms a flat roof or top to the stove or oven, and by that means
the heat from the fire or fires is spread out beneath the whole extent of the
said lowermost bottom for more effectually raising steam from the fresh
water; and the current of heated smoke, gas, and air, in proceeding further
onwards beyond that whole extent, then passes through suitable flues in a
drying stove (such as is commonly used for drying squares of fine salt) before
the said current begins to ascend the vertical chimney or stack, by which the
draft or current of air is produced and kept up for maintaining the combustion
of the fire or fires within the stove or oven and such other fire or fires as may
be used. But note, respecting such a salt pan as aforesaid having a double
bottom with some fresh water contained in the space between the two bottoms,
and having fire heat applied and spead out beneath the whole extent of: the
lowermost of the two bottoms to cause the said water to boil and raise steam as
in a steam boiler, which will act beneath the uppermost bottom for communi-

page_text: cating heat with uniformity throughout the whole extent of the brine which is
resting above that bottom, it is not new to use a salt pan of that description,
but it is new that one end or part thereof shall form a flat roof or top to the
aforesaid stove or oven containing the system of heated pipes through which
a current or currents of air is or are forced in order to become heated in like
manner as in the stove or oven of a hot-blast apparatus, as already stated, so
that the same fire or fires by which the said system of pipes is heated as would
be done in the stove or oven of a hot-blast apparatus also gives a heat beneath
the lowermost bottom of a salt pan of the aforesaid description, in the same
manner as would be done by the fire or fires which are usually applied beneath
one end or part of the said lowermost bottom of such a pan. The arrange-
ment of the heated pipes within the stove or oven aforesaid may be according
to any of those arrangements of such pipes which are or which have been
commonly used in the stoves or ovens of hot-blast apparatuses, such an arrange-
ment being selected as may be thought most convenient for saltworks, the
nature of such arrangements being, that the main pipe, through which the
whole current of cool atmospheric air is forced by the blowing cylinder or
other blowing machinery, shall be divided amongst several small branch
pipes which are disposed within the stove or oven so as to stand side by side
in a row, each branch extending over and across the fire or fires in the stove
or oven, but with spaces between the adjacent branch pipes for permitting
the flame, smoke, and heated air or gas to make its way upwards from the
fire or fires, through those spaces, in order to allow of the draft for causing
the fire or fires to burn, and also to give heat more effectually to the pipes by
the flame, smoke, and heated air acting in the spaces between the adjacent
pipes. And the heat which ascends through the said spaces into the roof or
upper part of the stove or oven will, according to this part of my improvements,
act beneath the lowermost bottom of the salt pan, part of which bottom, as
already mentioned, is to form a flat roof or top to the said stove or oven in
place of the usual arch or arches of firebricks which serve for the roof or top
of the stoves or ovens of ordinary hot-blast apparatuses. The main air pipe
from the blowing machine to the stove or oven may be there connected by
suitable large branch pipes with both ends of a horizontal pipe, which is dis-
posed along one side of the firegrate, so as to be at one side of the fireplace
which is above that grate, another like tube being similarly disposed at the
opposite side of the same firegrate to form the other side of the said fireplace;
and these two horizontal pipes are connected one with the other by a number
of semicircularly arched branch pipes of smaller size, which are fixed up side by
side in parallel vertical planes, across the lengthway of the firegrate, forming

page_text: a row, but with intervals between the adjacent arched pipes. One leg of each
arched pipe is fastened at its lower end into a socket in the upper side of one
of the said horizontal pipes, and the lower end of the other leg of the same
arched pipe is fastened into a like socket in the upper side of the other of the
said horizontal pipes, so that each arched pipe extends over across the fire-
place, and the whole number of such arched pipes being applied in like manner
in parallel vertical planes, or side by side in a row, they form the skeleton
of an archway over the whole extent of the fireplace, so as to receive heat
from the fire on the grate, and the flame, smoke, and heated air or gas has
free passage up through the spaces between the adjacent arched pipes. By
this mode the air is divided into the same number of small currents as the
number of the arched branch pipes aforesaid, and the air receives heat very
effectually whilst it is so divided into small currents; but nevertheless all the
said currents, after they have passed across over the fireplace within the arched
pipes, and acquired the intended heat, they become united again within the
horizontal pipe at the opposite side of the fireplace, and from the two ends of
that horizontal pipe the heated air passes away from the stove or oven through
suitable large branch pipes joining to one or more main hot-air pipe or pipes
which are provided for conveying the heated air to the salt pan, bencath the
bottom of which (according to this part of my improvements) the heated
air is to be applied for communicating heat to the brine that is resting on that
bottom. And when the stove or oven is of such maguitude as to require two
or more fires within it for heating the air, each of those fires will be crossed
over by a row of arched branch pipes similarly to that fire which has been
already described.
That horizontal pipe which is disposed between two
adjacent firegrates must have double sockets at the upper side of it for
receiving the lower ends of one leg of each of the arched branch pipes
belonging to the said two adjacent fireplaces, and so on in case of more than
two firegrates. The two outermost of the said horizontal pipes, which are
nearest to the boundary walls of the stove or oven, have only single sockets at
their upper
sides for receiving the lower ends of one of the legs of each of
those arched branch pipes which are to stand over that fireplace to which such
outermost horizontal pipe belongs; and the two ends of one of those outer-
most horizontal pipes is connected by suitable large branch pipes, as already
mentioned, with the main air pipe for conveying the whole current of cool
atmospheric air from the blowing machinery to the oven or stove; and the
two ends of the other of the said outermost horizontal pipes are connected by
suitable large branch pipes with a large hot-air pipe or pipes for conveying
the whole of the heated air from the stove or oven to the salt pan, beneath the
.

page_text: bottom of which, according to this part of my improvements, such heated air
is to be applied. And there are different ways in which the said heated air
may be so applied, the most simple being to support the pan so as to leave a
space for the reception of the heated air beneath the whole extent of its said
bottom whereon the brine is resting, that space being enclosed at all sides to
prevent escape of the heated air which is to be conveyed by the aforesaid hot-
air pipe or pipes into one end of the said space, and from a suitable opening
or openings, or pipe or pipes, at the opposite end of the same space, the air
is allowed to make its escape after having passed with a slow current beneath
all the extent of the bottom of the pan, and communicated a great portion
of its heat to the said bottom, and by transmission upwards through the iron
of that bottom to the brine that is resting thereon, whereby the air will
become considerably cooled when it is so allowed to make its escape; but as
it will still retain much heat, the escaping air should be conveyed into the
usual flue or flues of the drying stove that is commonly used for drying the
squares of fine salt, so as to assist in heating that drying stove. The said
space beneath the bottom of the pan may be enclosed at all sides by brickwork
built in cement, or may be enclosed by iron plate at the sides, to prevent
escape of the air, with brickwork outside of that iron to prevent loss of heat,
the lower part of the said space beneath the bottom of the pan being iron or
else brickwork set in cement. And note, although the said stove or oven,
which is to be used as aforesaid, has been compared to those of hot-blast
apparatuses for smelting iron with hot blast, because the construction is very
similar, yet it is to be understood, that it is not necessary that the air should
be forced with any considerable pressure, as must be the case for blast
furnaces for smelting iron, in order to cause the hot air to issue with a
great velocity of blast through the nose pipe into the furnace, but for the
purposes of this part of my improvements it is only requisite that the air
shall be compressed by the blowing machinery just as much as will cause it
to move forwards with suitable rapidity through the pipes in the stove or oven,
without afterwards forcing the air through any contraction like that of the
nose pipe for a blast furnace; but the large branch pipes and hot-air con-
veyance pipe, which extend from the stove or oven to the salt pan, are to be
of sufficient size to allow the air to pass freely onwards, and so of all the
pipes through which the air is to pass from the blowing machine, and through
the stove or oven to the salt pan. They are all to be of a size to allow the
air to pass freely onwards; and as to the heated arched pipes, although they
are of small size, they are numerous, and the air passes through them in as many
small currents. The blowing machinery may be of any kind which is used

page_text: for blowing air into furnaces, such as a revolving fanner, now most commonly
used by iron founders for blowing air into small melting furnaces; or a blowing
cylinder may be used, such as is commonly used for blowing air into blast.
furnaces for smelting iron, with a piston and four valves arranged in the
manner of a double-acting pump. And another mode of applying the heated
air to a salt pan according to this part of my improvements is,, to combine the
heating action of such air with the heating action of steam in a salt pan
having a double bottom, and the steam being applied in the inclosed space
between the two bottoms for communicating heat to the brine which is resting
upon the uppermost of the two bottoms; but the said heated air is to .be.
applied under the middle part of the width of the said uppermost bottom for
an extent of about one third of that width, and along the whole length of the
pan. For this purpose the said uppermost bottom is to be made to rise, with
a curved ridge along the said middle part, so that there will be less depth of
brine.resting on the said curved ridge at the middle part of the width thereof
than at the two sides of that ridge; and beneath the whole extent of the said
cuved ridge a surface of iron plates, of a similar but contrary curvature to that
of the ridge, is to be applied and fastened to the under side of the upperinost
bottom by rows of rivets applied along the two sides of the ridge, so as, between
the downward curvature of the said iron plates and the upward curvature of
the said ridge, to form a passage for the heated air along the whole length of
the
.pan, and beneath one third of the width of the uppermost, bottom whereon
the brine is resting. The said iron plates may be said to form a double
bottom beneath, about one third of the width of the uppermost bottom, for
the purpose of forming a passage for the heated air to pass in a current
along beneath so much of the brine, in order that heat may be transmitted
upwards from such current of heated air, through the iron of the curved
ridge part of the uppermost bottom to the brine which is resting on that
ridge part, so as to cause the said brine to boil and deposit fine salt,
but that salt is not to be allowed to accumulate upon the ridge part, for
at suitable intervals of time it is to be raked off therefrom towards each
side of the pan, and the form of the ridge part will facilitate such raking;
and at the said sides of the pan for an extent of about one third of its
width at each side the steam contained in the space between the upper-
most and the lowermost bottoms of the pan will be acting beneath the said
two sides of the width of the uppermost bottom, to communicate heat to the
brine which is resting upon those two sides, and the heat thereby com-
municated to the brine at the sides of the pan being augmented by the heat
communicated from the hot air to so much of the brine as is at the middle

page_text: part of the width of the pan, causes the latter brine to boil and deposit fine
salt. The main hot-air pipe or pipes, for conveying the heated air from the
stove or oven, is or are to join with the full-sized opening or openings of the
said pipe or pipes, into one end of the aforesaid passage beneath the middle
part of the uppermost bottom of the salt pan, so as to supply the aforesaid
current of hot air along that passage; and from an opening out of the other
end of the same passage, and at the farther end of the salt pan, the said
.current may be allowed to pass away freely through any suitable passage or
passages in to the flue or flues of the drying stove for drying salt, as already
mentioned; or the said current of air may be conveyed by any suitable passage
or passages into one end of another long passage, beneath the middle and ridged
part of the uppermost bottom of another second salt pan, like to that already
described, in order to form a current of heated air through the said passage of
that second pan, and from the further end thereof the current may be allowed
to escape into the flue or flues of the drying stove. Or the said second pan
may be a simple salt pan of the kind already described, without any steam
beneath it, but with the pan supported so as to leave a space beneath the
whole extent of the bottom whereon the brine is resting for the reception of
the heated air, so that it will pass with a slow current beneath all the extent
of the bottom of the pan, in order to communicate heat to the brine above
that bottom, and from the further end of that space the air may be allowed to
escape into the flue or flues of the drying stove. And note, when the heating
action of hot air, according to this part of my improvements, is to be used in
combination with the heating action of steam, as already explained, the said
steam may either be supplied in the manner already explained from the boiling
of water contained in the lower part of the space between the two bottoms
of the salt pan, that space answering the purpose of a steam boiler (and in
the upper part of which space the steam is to act as already explained), and
in which case fire, heat, and the flame, smoke, and heated air or gas proceed-
ing therefrom, must be applied beneath the lowermost of the two bottoms for
causing the said water to boil, and produce steam as in a steam boiler; or
otherwise steam may be conveyed by suitable steam pipes into the said space
between the two bottoms of the salt pan, so as to keep that space supplied
with steam, in which case no fire heat will require to be applied under the salt
pan itself. The said steam pipes may either convey the steam from a steam
boiler of any kind that is suitable for producing low-pressure steam, or they
may convey steam from the aforesaid space between the two bottoms of a
salt pan having fire heat applied beneath the lowermost of those bottoms, and
water in the lower part of the said space, so that it will answer the purpose of

page_text: a steam boiler as already explained, and with an adequate power of producing
steam, not merely for the supply of the said space with steam, for acting in the
manner already explained beneath the uppermost bottom to heat the brine
that is resting on that bottom, but also with a large surplus of steam for
supplying (through suitable steam pipes) the space between the two bottoms
of another salt pan or pans which has or have no fire heat applied beneath it
or them, but one or more of which salt pans may have a current of hot air
applied according to this part of my improvements in a passage or passages
along beneath the middle part of the width of the uppermost bottom of such
pan or pans, in the manner already described. And what I prefer for a
complete salt-making apparatus, to be constructed according to this part of
my improvements, is to have one large salt pan with double bottoms, and
some water in the space between those bottoms, and with fire heat of the
hot-air stove or oven (and of another fire, or other fires if needful), applied
beneath the lowermost of those two bottoms, in order that the said space may
act as a steam boiler for producing steam, not merely for the supply of the
said salt pan itself, but with a large surplus for supplying another salt pan or
other salt pans herein-after mentioned. Part of the said fire heat that is so
applied beneath the lowermost bottom of the said pan, will be that heat which
will necessarily ascend into the highest place within the hot-air stove or oven,
to which highest place one end or part of the lowermost bottom of the said
salt pan forms a flat roof or top, as already mentioned; and all the current
of flame, smoke, and heated air or gas which passes away from the hot-air
stove or oven being conveyed beneath other part, the lowermost bottom of
the salt pan assists in heating the water in the space above that bottom, and
in raising steam therefrom; and as much more fire heat as may be required
to be applied beneath the said lowermost bottom may be derived from a fire
or fires in a furnace or furnaces suitably disposed beneath other part of the
said bottom for the purpose of heating the same, also the current of flame,
smoke, and heated air or gas from such fire or fires is to be conducted beneath
other part of the said bottom, so that fire heat is given beneath the whole
extent thereof; and all the current of smoke and heated air or gas
(proceeding from all the fires) which remains after having so passed
beneath all the extent of the said lowermost bottom, then passes onwards
through the flues of the salt drying stove towards the vertical chimney, and
by ascending therein, the draft or current is occasioned for maintaining com-
bustion in all the aforesaid fires. But note, before arriving at the said salt-
drying stove, the said current may be conducted beneath the bottom of what
is called a back pan, for heating cold brine in preparation for charging the
.

page_text: salt pan with warm brine, in case of such a back pan being used; and the
cool air which is forced by the blowing apparatus through the heated pipes
of the hot-air stove or oven thereby becomes strongly heated in the manner
already described, and that hot air is then conveyed by the hot-air pipe or
pipes into one end of the passage for hot air, already described as extending
along beneath the middle part of the width of the uppermost bottom of the
salt pan, where that bottom rises with a curved ridge part, and the current
of heated air along that passage causes the brine that is over the ridge part
to boil, as already explained; and the said current of heated air, after having
thus passed all the length of the said passage, is then conveyed from the
further end thereof by suitable connecting passage or passages to one end of
the like passage of another second salt pan of the same or similar construction
as the first, except that there is no fire beneath the lower bottom of tlie sai
second pan, but the space between its two bottoms is kept supplied with steam
by suitable steam pipes or passages proceeding from the upper part of the
space between the two bottoms of the first pan to the second pan, and there
connecting with the upper part of the space between the two bottoms thereof, so
as to introduce a constant supply of steam into that space from the surplus
steam that is produced in the space between the two bottoms of the first pan
by action of the fire heat that is applied beneath the lowermost bottom of that
first pan, the said space thereof answering the purpose of a steam boiler, as
already mentioned; and after the said current of heated has passed through all
the length of the hot-air passage of the said second salt
pan and communicated
additional heat to the brine therein, then that current may pass onwards into
the flues of the salt-drying stove already mentioned. And the spaces between
the two bottoms of each of the said salt pans are provided with suitable safety
valves lightly loaded, for permitting the escape of any excess of steam. And
the surface of the water contained in the lower part of said space between
the two bottoms of the first salt pan (which space acts a steam boiler) must be
kept up to a constant level with the same care as is requisite for any other
steam boiler; and inasmuch as a great part of the steam that is produced in
that space is condensed in communicating heat to the uppermost bottom of
the pan, and the brine resting thereon, the water resulting from that con-
densation falls down again into the water beneath it as already explained,
thereby restoring a part of the water that had been raised in steam. And as
to the steam that is conveyed by the steam pipes or passages to the second
salt pan, the lower bottom of that pan is placed on a level so much higher
than that of the first pan that the water resulting from the condensation of
the steam in the space between the two bottoms of the second pan will run by
'

page_text: its own descent from the very lowest part of that space through suitable pipes
into the space between the two bottoms of the first salt pan to mix with the
water therein, and restore the water that had been raised in steam. And any
deficiency that may take place in the water in the space between the two
bottoms of the said first salt pan, must be made up in the usual mode of
feeding steam boilers. And another mode of applying the heated air afore-
said, or part thereof, to a salt pan according to this part of my improvements,
is to permit the said heated air; or part thereof, to issue out in small streams
beneath the surface of the brine, so that the hot air will become mixed with
the brine, and will ascend through the brine to the surface thereof, thereby
communicating much of its heat to the brine so as to cause it to boil, or so
as to assist in the boiling and evaporating in steam; and also the air will
absorb some moisture from the brine, so as to increase the evaporation. The
arrangement of the hot-air stove and of the first salt pan, will in such case
be the same as already explained, with a hot-air passage beneath the curved
ridge along all the middle part of the uppermost bottom of the salt pan; and
in addition to what has been so explained, there will be a number of small
bended tubes joined to the upper part of the said curved ridge, and
rising up therefrom above the level of the surface of the brine, and then
turning downwards again with an arched curve, descending into the brine.
near to the uppermost bottom of the pan, where those pipes terminate with
open ends, at which they will emit the hot air to mix with the brine and
operate in the manner already stated. The uppermost and curved parts of
the said pipes being above the surface of the brine, will prevent any brine
returning through those pipes, in case of the current of hot air ceasing when
the blowing machinery is stopped.
And for the more complete explanation of the manner of performing this
part of my said Invention, I have represented an apparatus constructed
according thereto in Sheet I. of the Drawings hereunto annexed, Figure 1
being a transverse section, and Figure 2.a longitudinal section, and Figure 3
a horizontal plan, all those Figures being drawn to a scale of half an inch to a
foot, or one twenty-fourth part of the real size, and the same letters and nume-
ral characters are used for reference to the same parts on all the said Figures.
A, A, a, a, is the large salt pan containing the brine from which the watery
portion is to be evaporated, so as to cause the brine to deposit crystals of
common salt on the bottom a, a, of the pan, which is twenty feet wide, as it
appears in Figure I, and sixty feet long, as it ought to appear in Figure 2 if
the whole length had been there represented, but the greater part of that.
length of sixty feet appears to be broken out and removed, and only the front

page_text: end and back ends of the whole pan are shewn. The heat by which the
evaporation is to be effected is derived from the fires on the fire grates
B', B, B³, and D, Figure 1, and the flame, smoke, and heated air or gas
arising from those fires ascends in the arched spaces beneath the curved air
pipes E', E', E³, through which pipes currents of air are constantly flowing, as
will be further described, and the air becomes heated by the heat which is
communicated to the said pipes. And after so heating all the curved pipes
E', E, E, the said flame, smoke, and heated air or gas ascends through the
narrow spaces that are left between the adjacent curved pipes E', E, E, (as
appears in Figures 2 and 3,) and acts beneath part of the lowermost bottom
F, F, of the salt pan A, A, a, a, to give heat to fresh water that is contained
in the lower part of the space F, F, A, a, a, A, which space and the water
therein extends beneath the whole area of the upper bottom a, a, upon which
the brine in the pan A, A, a, a, rests. The heat which is transmitted through the
lowermost bottom F, F, causes the water to boil rapidly, and the steam arising
from the boiling water ascends and acts beneath the bottom a, a, so as by
transmission through the metal thereof to give heat to the brine above that
bottom, and thereby cause evaporation from the brine. The steam which acts
in that manner beneath the bottom a, a, is condensed in the act of giving its
heat thereto, and the water resulting from that condensation accumulates in
drops beneath the bottom a, a, and falls down into the water beneath, ready to
be again boiled and raised into steam which in its turn ascends to act again
beneath the bottom a, a, which bottom must be made water and steam tight
at all its parts and at its junctions with the vertical sides A, A, so as to
prevent any of the brine above the bottom a, a, getting down to mix with the
fresh water in the space between the bottoms a, a, and F, F, for it is fresh
water that is supplied into the said space, and ought to continue fresh. The
fire grates B1, B2, B3, and D are situated beneath one end of the lowermost
bottom F, F, of the pan F, F, A, a, a, A, as shewn in Figure 2; but after the
flame, smoke, and heated air or gas has acted as already stated beneath the said
bottom F, F, at that end thereof which is over the fires, it then passes
through suitable openings 9 in the cross wall G, G, into the flue space beneath
the remaining extent of the bottom F, F, so that heat is communicated
beneath the whole area of the said bottom, and of the fresh water which is
resting upon that bottom F, F; the said flue space may be an open arca
beneath the bottom F; F, without any interruption to the passage of the flame,
smoke, and heated air or gas, the bottom F, F, being in that case sustained
by iron props disposed at suitable intervals apart, or else parallel walls may
be built beneath the bottom F, F, for supporting it, those walls being

page_text: in the direction of the current of flame, smoke, and heated air, and dividing
the space beneath the bottom F, F, into as many longitudinal passages or
long flues as may be convenient, or as many such flues as there are fire
grates. In either case, after the said current has passed beneath all the
length of the said bottom F, F, it may then proceed onwards into the flues of
a drying stove for the salt before ascending the vertical chimney, which
drying stove and chimney being as usual in ordinary salt pans, does not
require further explanation. In Figure 1 the three fire grates B', B, B³, are
represented with curved air pipes E', E', E³, over them, and one other fire
grate D, without any such air pipes over it; the action of the fire on the said
grate D, for giving heat beneath the bottom F, F, is the same as that of the
other fires, and as already explained. The several curved air pipes E, E, E,
are connected together into one system, and they operate in the same manner
for heating currents of air which are forced through them as those systems of
pipes inclosed in an oven or stove which are now commonly used for heating
the air which is blown into blast furnaces for smelting iron by what is
termed hot blast. The cool atmospheric air is urged forwards in a continual
current by any suitable kind of blowing machinery, such as a revolving fanner
or a blowing cylinder situated in any convenient place where it can be worked
by steam or water, or other power, and the said current being thereby urged
along through the main conveyance pipe H, Figure 1, to the system of heated
pipes E, E, E, which stand up across over the fire grates B1, B2, B, and are
inclosed within the stove or oven that is formed by the space comprised
between the two side walls I, I, I, I, and the front wall J, J, and the cross wall
G, G, and the lowermost bottom F, F, of the salt pan, forms a flat roof or top
to the oven or stove, in place of arches of brickwork which form the roof or
top in an ordinary hot air stove for hot blast. L is a branch pipe from the
main conveyance pipe H, and the cool air which proceeds from the blowing
machinery along H becomes divided into two equal currents along L and h;
the ends of both L and h are joined by suitable turn pieces, with flange joints
to the two ends of a long horizontal pipe M, which is disposed near to one of
the side walls I, and along one side of the fireplace, that is, over one of the
fire grates B. The horizontal pipe M has twelve sockets formed at its upper
side, into each of which sockets the lower end of one of the upright legs of
each of the twelve arched pipes E',E', is inserted and made fast with iron
cement, the lower end of the other upright leg of each of the same arched
pipes E¹ being inserted and fastened in like manner into a corresponding.
socket at the upper side of another horizontal pipe N¹, which is disposed
parallel to M along the opposite side of the aforesaid fireplace B', and between

page_text: the two adjacent fireplaces B¹, B; and in like manner another horizontal pipe N
(exactly similar to N¹) is disposed between the other two adjacent fireplaces B
and Ba; and the fourth horizontal pipe O (exactly similar to N) is disposed along
one side of the fireplace B³. The two horizontal pipes N¹ and Ns have double
sockets at their upper sides (that is, two rows in each pipe, and twelve sockets
in each row,) for receiving the lower ends of the upright legs of two sets of the
arched pipes, videlicit, the arched pipes E' and E are received and fastened
into the said double sockets of N', and the arched pipes Es and Es into the
double sockets of N. The two horizontal pipes M and O have single sockets,
videlicit, one row in each pipe, and twelve sockets in each row. The several
arched pipes being put together as is represented in the Drawing, they afford a
free passage for the cool air that is conveyed through L and h into each end
of the horizontal pipe M to pass up therefrom, divided into twelve small
currents, through the twelve heated arched pipes E¹, over the fireplace B', and
then down again to the horizontal pipe N¹, the air becoming considerably
heated in so doing. And then the same air ascends and descends in like
manner through the twelve heated arched pipes E, over the fireplace B³, and
down again to the pipe N2, the air becoming further heated in so doing.
And then in like manner the same air ascends and descends again through
the other twelve arched pipes E³, to the horizontal pipe O, by which time the
air is become very strongly heated; and then from the two ends of that pipe O
the heated air passes onwards to the salt pan, videlicit, from the front end of
O the heated air passes into an ascending pipe Q, the lower end of which is
joined to the said end of O by a suitable turnpiece with flanges, and the upper
end of Qis joined by a flange to the front end of the salt pan, and from the
further end of () the heated air is conveyed by a horizontal pipe R, the further
end of which is joined to the said further end of O by suitable turnpieces with
flange joints; and the front end of R is joined by a turnpiece with flanges to a side
branch of the aforesaid turnpiece, by which the front end of O is joined to the
lower end of the ascending pipe Q, and by those connections the said ascending
pipe is kept supplied with a full current of heated air proceeding from both ends
of O; and Q conveys the whole of the heated air up to the front end of the salt
pan into the front end of a long hot-air passage S, Figure 1, which extends along
the whole length of the salt pan from end to end thereof, and occupies about one
third of its width, being in the middle part of that width; and the said passage S
is formed, as is shewn in Figure 1, by the uppermost bottom a, a, of the salt pan
being bended upwards into a curved ridge b, b, and by iron plate d, d (which
is bended downwards with a similar curve), applied beneath that ridged
part b, b, and rivetted along both its edges to the bottom a, a, where the said

page_text: ridged part thereof commences its rise from that bottom. The hot air, passing
with a slow current along the passage S, gives heat to the brine that is above
the curved ridge b, b, particularly at the summit part of that ridge where the
depth of the brine is least; and the brine having been already strongly heated
by the steam acting beneath the bottom a, a, as already explained, the further
accession of heat from the hot air in the passage S will cause the brine to boil
and deposit fine salt, but which will fall principally at the lowest parts and sides
of the curved ridge b, b, and the salt which does fall upon that ridge is not to
be allowed to accumulate too much thereon, but is to be raked down the
curved sides of the ridge from time to time, and gathered towards each
side A, A, of the pan, in preparation for being taken out in the usual manner
of salt-making. The bottom a, a, rises slightly each way from the two sides
of the ridged part b, b, towards each side A, A, as shewn in Figure 1, so that
the brine will stand deepest along each side of the curved ridge b, b, and less
deep at the two sides A, A, and still less depth over the ridge b, b, And the
current of heated air, after passing all the length of the hot air passage S, then
passes onwards from the remote end thereof, through suitable passages for
conveying the said current either directly into the flues of the salt-drying stove;
or else, previously to thus going into those flues, the said current may be passed
through the hot-air passage corresponding to S in another second salt pan, such,
for instance, as is shewn in section in Figure 4, and which is similar to that repre-
sented in Figures 1 and 2, except that there is no fire heat applied beneath its
lowermost bottom, but, instead thereof, the space between its two bottoms
is kept supplied with steam by suitable connecting steam pipes or passages
from the space between the two bottoms a, a, and F, F, of the first salt pan,
represented in Figures 1 and 2. The three fires on the fire grates B', B², B³,
being well kept up, will maintain a strong and uniform heat within all parts of
the stove or oven, so as to give a continual and regular heat to all the thirty-six
arched pipes E, E³, E³, and consequently to the currents of air that are passing
through them. The four horizontal pipes M, N, N³, and O, being so close to
the fires, are kept very hot, and they assist in heating the air. But note, to
prevent those horizontal pipes from being over-heated, the brickwork that forms
the sides of the fireplaces is carried up at the sides of the said pipes to protect
then from the most intense action of the fires. The pipe R being within
the oven, although at one side thereof, and near to the side wall I, will be kept
sufficiently hot to assist in heating the air that is passing through it.
.
In Figure 2, V shews the manner of applying a safety valve at the upper
end of a pipe which joins to the upright side or end A, A, of the pan below
the level of its upper bottom a, a, and the safety valve is very lightly loaded

page_text: for allowing any excess of steam to make its escape without causing any con-
siderable pressure beneath the bottom a, a, of the pan. There may be one
such safety valve at each end, and two at each side of the pan, and f, f, shew
the junctions for steam pipes or trucks by which steam is to be conveyed away
from the space between the two bottoms a, a, and F, F, of the salt pan, in
order to be supplied to the corresponding space or spaces of another or of other
like salt pans, but which has or which have no fire heat applied beneath its or
their lowermost bottom or bottoms. The said junctions f, f, are short lengths
of large pipes joined to the upper bottom a, a, at the angles of the pan, to give
ample passage for the steam upwards through that bottom a, a, and the upper
ends of the pipes f, f, are joined to rectangular trunks, made of thick wood
plank, which serve as pipes for conveying the steam to the other salt pan
or pans aforesaid, and do not waste so much heat by radiation as iron pipes,
and sluices are provided in those wooden trunks to stop the passage of steam
through them when required. And in case of a second salt pan being used, as
above mentioned, with the current of hot air passing through its hot air
passage, after the same current has previously passed through the passage S of
the first pan (being that which is represented in the Drawing), and which second
pan, as already stated, will not have any fire heat applied beneath its lowermost
bottom, but, instead thereof, the space between its two bottoms will be kept sup-
plied with steam from the said first pan. The lowermost bottom of such second
pan may be made of thick wood planking, in the manner shewn by the trans-
verse section, Figure 4, where A, A, are the upright sides, and a, b, b, a, the
uppermost bottom whereon the brine is resting, b, b, being the curved ridge
part along the middle part of that bottom, and d, d, the iron plate beneath that
ridge for forming (together with that ridge) the hot-air passage S; all which
is the same as in Figure 1, and as already explained. But the lowermost
bottom l, m, 1, Figure 4, descends with double inclinations from each side 1, 1,
towards the middle m of its width (as is there shewn), in order that all the hot
water resulting from condensation of the steam beneath the uppermost
bottom a, a, may run down from each side l, l, towards the middle m; and the
said lowermost bottom l, m, l, is made of long planks of wood, put together
with the edge of one plank overlaping the edge of the plank which is next
below it, as appears in the Figure; and all those overlapping edges are firmly
fastened together by nails or pins put through both, so as to render the joints
water and steam tight, or as tight as they can be made. The lowest and
middlemost of the planks m is cut out like a gutter, which extends all the length
of the pan; and being rather lower at one end of that length than at the other
end, the water which runs down from the sides 1, l, to the gutter m, will run

page_text: along the latter to the lowest end thereof, and therefrom it can descend
through a suitable pipe into the space between the two bottoms of the first
pan, Figures 1 and 2, which, as already mentioned, is so much lower than the
second pan, Figure 4, that the said hot water will run back from the second
pan to the first one. The wood planking of the bottom l, m, 1, Figure 4, may
be supported on rammed earth, or on walls of brickwork, or on beams of wood.
And in place of the said wood planking l, m, l, or part thereof, brickwork
built with cement, and stuccoed therewith, may be substituted.
[T, t, and T, t, Figure 1, represent the small bended tubes, already men-
tioned, for conveying small streams of hot air down into the hot brine in the
salt pan, Figure 1 (which has been called the first pan), so as to mix with that
brine and give more heat thereto, and assist in the evaporation of water there-
from. Each bended tube T, t, is formed of two pieces T and t, which are united
together by a flange joint situated above the level of the brine, as is shewn in
Figure 1. One of those picces T is firmly fixed by means of a flange, which
is rivetted to the curved ridge b, b, of the upper bottom a, b, b, a, of the salt
pan, that curved ridge being, as already explained, the upper part of the hot-
air passage S, and therefore the hot air will pass up through the piece T above
the level of the surface of the brino, and then down the other piece t, beneath
that surface, nearly to the bottom a, a, and the piece t is open at the lower
end, which is enlarged with a trumpet mouth, the border edge whereof stands
very near to that bottom a, a, .so as to leave a narrow crevice between
the bottom a, a, and the lower end of t, all around the trumpet mouth;
and it is through that crevice that the hot air is emitted in a constant'
small stream, so as to mix with the brine, and, in ascending in bubbles through
the brine to the surface thereof, the hot air communicates its heat to the brine
and absorbs moisture therefrom; so as to assist the evaporation of the watery
portion of the brine, the air making its escape along with the steam of the said
evaporation, and in mixture with that steam. A number of the tubes T, t, are
thus applied at opposite sides of the ridged part b, b, as appears in Figure 1, the
whole number of tubes T, t, forming two rows along the lengthway of the pan,
and the tubes T, t, being disposed at intervals of about ten feet from one tube
to the next in each row. By disjointing the piece t at its flange joint both the
parts T and t can be cleared from any obstructions of salt that may be formed
within them. The pressure of the hot air within the hot-air passage S must
be sufficient to enable the air to force its way down beneath the brine. And
in case it is intended that the whole of the current of hot air that is forced into
the passage S through the pipe Qis to be emitted through the several tubes T, t;
into the brine (so that the whole of the hot air will be allowed to make its

page_text: escape along with the steam of the evaporation), then the further end of the said
passage S must be closed without any passage onwards therefrom. But in
case only a portion of the hot air is intended to be so emitted into the brine,
then the remainder of the current of hot air must be allowed to pass onwards
from the further end of the passage S in order to escape into the flues of the
salt-drying stove, or else through the air passage S of a second salt pan (which
may be such as Figure 4, but without any of the tubes T, t), previously to
escaping into the said flues of the salt-drying stove. And the opening or
passage through which the current of hot air is allowed to make its final escape
into those flues must be restricted io such a size as to provent a free escape,
but so as to retain the current of hot air within the hot-air passage S of the first
(or of the first and second salt pans) under a sufficient pressure to cause the
hot air to force its way out from the lower ends of t, t, beneath the brine.
And note, when none of the tubes T, t, are used, so that the whole current of
hot air must be allowed to pass onwards from the father end of the hot-air pas-
sage S of the first (or of the second) salt pan, as herein-before explained, in such
cases the opening or passage through which the said current is thus allowed
to pass onwards from such father end should be restricted to such a sizo as to
keep a sufficient pressure of the current of hot air within the hot-air passage
or passages S, to prevent any brine making its way into such passage or pas-
sages through any minute leaks that may happen to take place in the iron
plates of the curved ridge part b, b. And note, the first salt pan, Figures 1
and 2, may be without any tubes T, t, for emitting hot air, and the whole
current thereof will pass onwards into the passage S of the second salt pan,
Figure 4, and that pan may have tubes T, t, as there shewn, for emitting the
whole or part of the hot air to mix with the brine in that second pan. In case
of a non-condensing high-pressure steam engine being used for working the
blowing machinery, the waste steam that is discharged from such an engine
may be conveyed into the space between the two bottoms of the salt pan or
pans, to form part of the supply of steam thereto.
[Another part of my improvements in apparatus for manufacturing salt
consists in the application of machinery for the purpose of what is termed
raking the salt from the bottoms of salt pans, and which is now commonly
performed by hand labour, see Sheet II. of the Drawings hereunto annexed,
wherein Figure 5 is a vertical transverse section, and Figure 6 a horizontal
plan of a salt pan, with machinery constructed according to this part of my
improvements. A, A, are the vertical sides, and B, B, the ends of the salt pan,
which is represented 20 feet wide, and may be supposed to be 60 feet long,
but the greater part of its length is represented as broken out, and only the

page_text: two end parts are shewn. The rakers can be drawn by the machinery in the
direction of the lengthway of the pan from one end thereof to the opposite end,
and can then be drawn back again. The rakers, when they are moving along
in that manner, can either be kept raised up from the bottom of the pan so as
not to act upon the salt, or else they can be let down so as to rest with their
weight upon the bottom of the pan, in order to rake the salt before them
towards one of the ends of the pan, contrary to the usual mode of raking by
hand, which rakes the salt from the middle towards the two sides of the pan.
The rakers, which are marked 1, 1, 1, 1, are applied one at the end of another,
in a line, so as to form a long compound jointed raker, extending all across the
width of the pan from side to side; eight such rakers 1, 1, 1, 1, are shewn in
Figure 6, they are all connected by joints 1, 1, to one long horizontal axle of iron
2, 2, which is supported upon small travelling wheels 3, 3, at each end of it,
and one large travelling wheel 4 at the middle of its length, the wheels 3, 3,
running upon horizontal bearing rails 5, 5, which are fixed along each side A, A,
of the pan; and there are other fixed rails 6, 6, above the wheels 3, 3, to pre-
vent them from rising up by accident from their bearing rails 5, 5. The large
wheel 4 runs along the iron bottom of the pan. All the three wheels, 3, 4,
so as to turn round freely
and 3, are fitted on round parts of the axle 2, 2,
thereon in order to sustain its weight, but so as to permit it to be moved with
a travelling motion parallel to itself, in a horizontal direction lengthways of the
pan across which it is extended, first travelling towards one end of the pan,
then back again towards the other end thereof. Each of the rakers 1 is
connected with the axle 2 by means of an cye 1, 1, that is fitted freely on a
round part of the axle 2, to form the joint by which the raker is connected
with the axle; and the eye 1, 1, has two diverging.prongs 13, the ends whereof
are firmly fastened to the raker 1, which is a broad plate of iron, as shewn in
Figure 5, with its lower edge resting on the bottom a, a, of the pan, the weight
of the raker and its diverging prongs 13 being operative to to bear the said
edge down towards that bottom, and all the rakers can be turned partly round
about the said joints or fittings of their eyes 11, upon the axle 2, so as to raise
up the rakers from the bottom of the pan when they are not required to act
upon the salt, or they can be turned quite over about their said joints in order
to place the rakers on the opposite side of the axle 2 to that in which they are
represented in the Figures, so that when they are so turned over, the other
edges of the rakers which appear to be the uppermost in the Figures will
become the lower edges, which will rest on the bottom of the pan. The eight
rakers 1, 1, 1, 1, must be all turned over to the saine side of the axle 2,
either one side or the other thereof, according to the direction in which

page_text: it is intended that the salt shall be raked along the bottom of the pan,
because the rakers must follow after the axle during such raking action.
The axle 2, 2, with its wheels 3, 4, 3, and the eight rakers 1, 1, 1, 1, is
caused to travel in one direction so as to advance it parallely to itself
towards one end of the pan, by means of four ropes 7, 7, 7, 7, which are
then wound up around four drums 8, 8, 8, 8, as fast as the same are
turned round by their machinery in the proper direction for winding up the
said ropes 7, and alternately the axle wheels and rakers are caused to travel
back again towards the other end of the pan by four other ropes 9, 9, 9, 9,
which are then wound up around four other drums 10, '10, 10, 10, as fast as
the same are turned round in the proper direction for winding up the said
ropes 9, the first-mentioned drums 8 at the same time turning backwards to
allow the ropes 7 to unwind from off them; and in like manner, when the drums
8 were winding up the ropes 7 (as first mentioned), then the druins 10 turned
backwards to allow the ropes 9 to unwind from off them. The four drums 8
are all fastened upon one long horizontal axis 14, which is sustained in suitable
bearings in a direction across one end B of the pan, but at some distance
beyond that end, and at some height above the same, as appears in Figure 5;
and the four drums 10 are in like manner all fastened upon a similar hori-
zontal axes 15, and by means of an endless rope 25 passing around two large
drums 26 and 27, which are fastened on the two axis 14 and 15 respec-
tively, those two axes with all the drums on each are caused to turn round
with like motions. The axis 14 is turned round when required by the power
of the millwork first in one direction and then in the opposite direction by
means of three equal bevil or mitre cog wheels 17, 18, and 19, the teeth of which
are always in gear together. The wheel 17 is fastened on one end of a short
cross axis 18, which has another mitre wheel 20 on the other end of it, and
that is turned round by a corresponding mitre wheel 21, which is fastened on
the long horizontal axis 22. That axis 22 is part of a long line of such axes
which also serve to actuate the machinery of other salt pans; and it is kept
continually turning round by steam or water power; and by the wheels 21 and
20 it turns the axis 18 and and wheel 17, which latter turns the two wheels
18 and 19 continually round in contrary directions one to the other; but as
both those wheels 18 and 19 are fitted on round parts of the axis 14, so that
they can turn round thereon, they do not necessarily give any motion thereto,
except by means of a sliding clutch box 23, which is fitted on the axis 14, so
as that it can be slided endways along the axis, but it cannot turn round
without carrying the axis 14 round with it. When the said clutch box 23 is
slided along the axis 14 towards the wheel 18, certain teeth on the centre boss

page_text: of that wheel catch into corresponding teeth at the end of the clutch box 23,
and thereby the wheel 18 is caused to carry round the clutch box 23 and the
axis 14, together with all the drums 8 thereon, in the same direction as the
said wheel 18 is revolving. The four drums 8 then begin to wind up the
four ropes 7, and they cause the axis 2 and its wheel 3, 4, 3, with all the eight
rakers 1, 1, to travel along the lengthway of the pan- towards those drums 8.;
and the rakers 1 (which have been previously let down to rest on the bottom
a, a, of the pan) will rake the salt along the bottom a, a, towards the end.B of
the pan.
But note, before the axis 2 began travelling and raking the salt as
aforesaid in the direction above described, all the rakers 1, 1, had previously
been turned over to the opposite side of the axis 2 to that side thereof on
which they appear in the Figures, so as that the rakers would follow after the
axis when they were in the act of raking the salt before them. Note, the
fcur drums 10 (in consequence of the motion given to their axis 15 by the
endless rope 25 and drums 26 and 27) unwind the ropes 9 as fast as
the other four drums, 8 wind up the ropes 7; and when the axis 2 with the
rakers has arrived as near to the end of the pan as it is intended to go,
then the clutch box 23 is slided along the axis 14 so far away from the wheel
18 as to disengage the teeth of the box from those of the wheel, and then,
although the wheel 18 continues to turn round as before, it ceases to give any
motion to the axis 14, which, together with its drums,. will remain motionless..
Then, as a preparation for travelling in a contrary direction, or returning
without any raking action during the return, all the rakers are raised up by.a
small motion of their joints 11 about the axle 2, and they are kept raised
that they will no longer act upon the bottom of the pan, which being done,
then the clutch box 23 is slided so far along the axis 14 towards the other
wheel 19 (which is continually revolving in a contrary direction to the wheel
18) as to engage the teeth on the centre boss of the wheel 19 with the corre-
sponding teeth on the end of the clutch box, and thereby the axis 14 with its
drums 8 will be carried round in that direction, which will begin to unwind the
ropes 7 from off. those drums, but at the same time the axis 15 (by means of
the endless rope 25 acting upon the two large. drums 26 and 27) is turned
round so that its four drums 10 will begin to wind up. the four ropes 9, and
they will cause the axes 2 with its wheels 3, 4, 3, and all the rakers 1,-1,. to travel
along the lengthways of the pan; but the rakers cannot rake the-salt this time
because they are kept raised up from off the bottom of the pan; and when
they have arrived as. near to the end of the pan as they are intended to go,
then the clutch box 23 is slided along the axis 14, so as to disengage it from
the wheel 19, which, although it continues to turn round, it leaves the axes-14
so

page_text: motionless, and also the axes 15 with all the drums on both these axes. The
rakers are then let down again to bear on the bottom of the pan, and the clutch
box 23 is again engaged with the wheel 18, in order to rake the salt again as
before. Note, the several ropes 7 and 9 are connected with the axis 2 by
means of iron links which have eyes to fit upon the axis, and other eyes for
fastening the ropes to; and the lengths of the ropes must be adjusted so that
all four will pull equally. The endless rope 25 is a broad flat rope, composed
of four or more ropes sewn together side by side, to obtain good hold around the
circumferences of the two drums 26 and 27; and what is termed a tightening
pulley should be applied to the upper part of the endless rope 25, to prevent
slipping of that rope on its drums 26 and 27; or, instead of the endless rope
25, two distinct ropes may be applied to the two drums 26 and 27 (or broader
drums in their places) to wind on and off in contrary directions, one rope
being above and the other below the drums, so that the two ropes will have
the same appearance as 25, 25, in Figure 5, and they will compel the drum
27 and axis 15 to turn round one rope backwards and the other forwards
alternately, with like motions to that of the drum 26 and axis 14; or other-
wise, instead of the said drums and endless rope or ropes, the axis 15 may be
turned round by means of a long horizontal axis extending parallel to the
lengthway of the pan from the axis 14, with mitre bevil wheels at each
end of that long axis working into corresponding wheels on the axes 14 and
15, which will in that way be made to turn round with like motions one to
the other, either backwards or forwards. And the mitre bevil wheels 18
aud 19 with their sliding clutch box 23 may be applied on that long hori-
zontal axis, if convenient, instead of being on the axis 14. And a. suitable
lever handle must be provided for moving the said sliding clutch box 28
along its axis when required, as already explained; and to the handle end of
that lever handle a long rod or rods should be connected and extended hori-
zontally in the direction of the lengthway of the pan along each side thereof,
in convenient situations for the workmen to take hold of such long rod or
rods at any part of of the length of either, so as by pushing or pulling the
same endways to be able to give the requisite sliding motion to the clutch box
23 for putting the machinery in motion in either direction, or stopping its
motion as it is required. And projecting stops may be fastened on the said
rods at suitable places on their lengths, so that any convenient part which
partakes of the travelling motion of the axle 2, or some picce projecting out
from such part, may come into contact with those stops, and give such
motion to the rod as will disengage the clutch box 23, and stop the motion
whenever the travelling has continued as far as it is intended to do in either.

page_text: direction. And as to the lifting up of the rakers from off the bottom of the
pan before they begin to travel in that direction in which they are not
required to rake the salt, and also the letting of the rakers down again upon
the bottom before they begin to travel in that direction in which they are
required to rake the salt, such lifting up and letting down may be performed
by the workmen who attend the machinery. And to enable them to do so, a
wheel with handles projecting out from its circumference, like the steering
wheel of a ship, is to be firmly fastened on each extremity of the axle 2, 2,
beyond its two travelling wheels 3, 3, in the manner shewn at 29, 29, Figure 6,
and seperately in Figure 7. The men, by taking hold of the handles of either
or both those wheels, can turn the axle 2 round; and for each of the rakers 1
a forked clutch 30 is fastened to the axle 2, close to the eye 11 and prongs 13
of the raker, so that when the axle 2 is turned round by its handle wheels 29,
as aforesaid, all the forked clutches 30 turning with the axle 2, they will catch
the several prongs 13, so as to lift up all the several rakers 1 at once, and
take their lower edges off the bottom of the pan. And in order to keep all
the rakers so raised up, the handle wheel 29 must be retained from turning
back again, which may be done by inserting a stop pin 31 through a suitable
hole in the rim of 29, to enter into a corresponding hole in the end of the axle
of a small additional travelling wheel 32, which runs in the space between
the two rails 5 and 6, in the same manner as the wheel 3. The said axle of
the wheel 32 projects out from one end of a piece 83, which is fitted on to a
round part of the end of the axle-2, close within its travelling wheel 3. And
at the opposite end of the same piece 33 is the axle of another small travelling
wheel 39, which also runs in the said space between the rails 5 and 6; and
it is by turning the handle wheels 29 and the axle 2 more than half round
that all the rakers 1 are turned quite over to the opposite side of the axis 2 to
that side thereof at which they appear in Figure 5. That turning over is
required in order to prepare for raking the salt towards a different end of the
pan to that end towards which the raking had previously taken place. The
rakers 1 must in, all cases be turned over towards that end of the which is
the contrary end to that towards which the salt is about to be raked. The
forked clutches 30 are very, open, so as to leave the rakers quite at 'liberty
when they are let down to rest on the bottom of the pan, so that each one will
bear by its own weight on that bottom in order, to, apply to the inequalities
The machinery
thereof, without any interference from the other rakers.
above described may be used. either for raking the salt from all the length of
the pan to.one end thereof (in which case the aforesaid turning over of the
rakers will not be required), or else for raking the salt from half of the length
pan

page_text: of the pan to one end thereof, and from the other half to the other end, in
which case the rakers must be turned over every time that the direction of
the raking is changed to be towards one end instead of the other end; and
although (as has already been mentioned) the rakers can travel from one end
of the salt pan to the other, nevertheless the extent of their travelling motion
will be continually varying during the whole operation of raking the pan,
which must necessarily be performed at several journeys, because the rakers
must only gather up a suitable quantity of salt before them at each journey,
and therefore the number of journeys they must make, and the distance they
must travel at each journey,. must be adapted for gathering up that suitable
quantity of salt before the rakers at each journey.
The mode whereby the aforesaid machinery operates for raking the salt
along the bottom of the pan towards either end thereof being now explained,
it remains to describe the manner whereby the said machinery operates for
drawing the salt out of the pan. For that purpose a long moveable table
40, 41, is applied at one end of the salt pan, with its lengthway across the
width of the pan, and the middle of the breadth of the table is upheld by
being poised on a horizontal centre line of motion 42, which is sustained on
suitable supports a little beyond the end of the pan, and a little above the
level of the upper edge thereof. The table 40, 41, can be tilted laterally
about its said centre line 42, so that one edge 40 can be put down to touch
the bottom of the salt pan, whereby the other edge 41 will be raised up to a
considerable height, as appears in Figure 5, in which position the table forms
an inclined plane, up which the salt will be drawn by the rakers 1 of the
machinery, so as to raise the salt above the level of the brine; and in order to
do that, the wheel 4 at the middle of the axis 2 will run up the inclined plane
40, 41, of the table, and the bearing rails 5, 5, for the wheels 8, 3, at the two
ends of the axle 2, and the other fixed rails 6, 6; over those wheels, all which
rails, although they are horizontal along the greater part of the length of the
pan, and have been mentioned as horizontal rails, are nevertheless inclined
upwards near to the end of the pan, as is shewn in Figure 5, suitably for
causing the two ends of the axle 2, 2, to ascend at the same time, and in a
corresponding manner to the ascent of the middle part of the length of that
axis 2 by its wheel 4 running up the inclined plane 40, 41, of the table as
aforesaid; and the four ropes 9 are at that time pulling (by the winding up
around their drums 10) with a suitable inclination for causing the axle 2 and
rakers 1 to mount easily up the incline of the table, so as to rake the salt up
the same until it is raised thereon above the level of the brine, and then the
further motion of the machinery is stopped. The rakers 1, 1, are then raised

page_text: up by means of their handle wheels 29; 29, and are kept raised by inserting
the stop pin 31 so as to take all the rakers off the table 40, 41, and out of
the way of the salt which is upon the table, and from which the the brine
begins to drain away and run down the incline 41, 40, of the table into the
brine in the pan. The machinery is then put in motion again in a contrary
direction to its last motion, and the axis 2, with its wheels 3, 4, and 3, and the
rakers 1, 1, descend the inclined parts of the rails 5, 6, and the inclined table
40; 41; to the bottom of the pan, and then begin to travel along the same;
but the rakers being held up as shewn in Figures 7, they are above the
bottom of the pan and the brine therein, because they are not intended to
operate when travelling in a direction away from the table 40, 41; and when
the rakers have travelled so far along the pan in that direction as to have
passed over as much of the salt that is lying on the bottom of the pan as the
workmen judge by experience to be a suitable quantity for the rakers to gather
up before them at the present journey, they stop the further motion of the
machinery, and then withdraw the pins 31 and let down all the rakers to rest
on the bottom of the pan. Then they put the machinery in motion again
in a contrary direction, so that the rakers will begin to travel towards the
inclined table 40, 41, and in so travelling they will rake the salt before them
along the bottom of the pan towards that table, and then up the incline thereof
until the salt is raised above the level of the brine in the pan as before. In
this manner at successive journeys of the rakers as much. of the salt can be
accumulated on the surface of the inclined table 40, 41, as may be desired,
and the brine is continually draining away from that salt down the incline of
the table into the brine in the pan, until the salt is sufficiently drained, and
then the salt is discharged from off the table 40, 41, by tilting the same about
its centre-line of motion 42, so as to raise up its edge 40 and depress its edge
41, in order to give it so much inclination in a contrary direction to that
represented in Figure 5, as will cause all the salt that is upon its upper surfaco
to slide down therefrom and descend into the place where the salt is to be
stored by aid of such inclined shoot or shoots as may be required for con-
ducting the salt to that place, or else into a carriage or vessel into which the
salt is to be loaded or conveyance. The table 40, 41, being thus cleared of
the salt which has been raked up out of the pan by the machinery, the table
is then tilted back again to its former inclined position with its edge 40
resting on the bottom of the pan, as represented in Figure 5, in readiness for
having more salt raked up upon its inclined surface 40, 41, by repetitions of the
operation of the machinery, as above described. The lower edge 40 of the
table must be bevilled to fit to the bottom of the pan, so as to allow the upper

page_text: surface of the table to go down close to that bottom, in order to permit of the
rakers raking up the salt from off the flat bottom of the pan on to the inclined
surface of the table. The table 40, 41, must be securely propped beneath its
highest edge 41, or otherwise fastened when it is in its inclined position
Figure 5, because the salt that is to be accumulated upon the table and lay
there for draining from the brine, as already described, must all be above
the level of the brine, and therefore will be in great part beyond the centre
line 42 about which the table is to be tilted, and therefore the principal
weight of all that salt will be operative to tilt the table the contrary way with
the edge 41 downwards, so that when the workmen remove the said props, or
other fastenings, the table will be ready to tilt up by the weight of the salt
upon it, in order to discharged that salt in the manner already described; but
after the salt has been so discharged, then the weight of the table itself, with-
out any salt upon it, will be nearly balanced, so as to be very easily restored
to its proper inclining position, as in Figure 5. The said props may be made
with racks and pinions or screws, in the manner of what are called hand jacks
suitably applied, so that by means of the winch handles of such, pinions or
screws the workmen may allow the table to tilt up by the weight of the salt
with a very gradual motion. And .note, it is not necessary that the table
should be so wide as to descend into the brine at all; because all that lower
part 40 of the width of the table, which is represented in Figure 5 as being
immersed in the brine, may be omitted, provided that the end of the salt pan
itself is made with an inclination like that of the surface of the table from 40
upwards to the height of other parts of the edge of the pan, and what would
then be the lower edge of the table, would join to the upper edge of the
inclined end of the pan in continuation of the inclination thereof, but with
such an overlap of the said lower edge of the table over the upper edge of the
inclined end of the pan as to ensure that the drainings of brine from the salt
that is accumulated on the table would run down into the pan. The table
would in such case be narrower than is represented in Figure 5, by all that
part of the width which is immersed in the brine. Such narrower table might
be poised on a centre line of motion, such as, 42, but situated so much further
from the pan and higher up than 42 as that the weight of the table, with the
required accumulation of salt upon it (and also without any salt upon it),
would be so nearly balanced as to render it easy for the workmen to manage
the tilting of the table either way; and although only one end of the salt pan,
Figure 5 and 6, is shewn to be furnished with an inclining table 40, 41, for
receiving the salt, it is. to be. understood that the other end of the same salt
pan may be furnished with a, similar table, if desired, in which case the rakers

page_text: must rake the salt from one half of the length of the pan to one end, and
from the other half thereof to the other end; and (as already explained) the
rakers are qualified for doing that by turning them quite over to one side or
other of the axle 2, when required. The machinery represented in Sheet II.,
and above described, is adapted for raking and drawing out of the pan such
salt as is sold in a loose state; but salt which is to be dried in masses ór
squares requires a different mode of treatment.
.
[Another part of my improvements in apparatus for manufacturing salt con-
sists in the means represented in Figures 8, 9, and 10, Sheet III., for gathering
salt into suitable moulds for forming that salt into masses or squares.
Machinery similar to that represented in Sheet II. is to be used for raking the
salt along the bottom of the salt pan, which, if it is constructed according to
the first part of my improvements, will have a curved ridge along the middle
part of the width of its bottom, as is shewn in Figure 1, Sheet I., at b, b, and
the rakers of niachinery, such as is represented in Sheet II., must be adapted
to rake along the two side portions a, a, Figure 1, of the bottom of the pan
without raking over the curved ridge b, b, from which ridge the salt has been
previously raked by hand down to the parts a, a. (Note, the tubes T, t, T t,
Figure 1, are not to be used.) The said machinery, which is similar to
Sheet II., having raked the salt in the manner already explained along the
bottom a, a, Figure 8, of the pan to one end thereof, then raises the salt up
a short inclined plane 50, 51, Figure 8, precisely in the same manner as
already described for raising the salt up the inclined table 40, 41, Figure 5;
but the salt which has been so raised up the said short inclined plane 50, 51,
Figure 8; then falls into the mould 52, 52, which is placed within the pan
across the end B thereof, close behind the inclined plane 50, 51. The interior
of that mould thus becomes filled with salt, with somo excess. The mould 52
is represented in Figure 9 (which is a horizontal plan) with six spaces in the
mould, which is only a frame with sides, ends, and five cross partitions, without
any bottom or top to the mould; but the mould 52 is placed on a loose board
58 to serve for a temporary bottom, and the board 53 stands on the bottom
a, a, of the pan on suitable supports of short legs or feet e, e, so as to bring
the top edge of the mould 52 to conform with the upper edge 51 of the
inclined.plane, the mould being then open at top without the board,56, Figure 8.
The rakers of the machinery, after having mounted up the incline 50, 51, will
then move horizontally for so far as is requisite for filling the salt completely into
the said spaces in the mould 52, which horizontal motion of the rakers is obtained
by giving a suitable form to the rails 5 and 6, Figure 5, Sheet II.; between
which the travelling wheels 3, 3, for the rakers move, as already.described;

page_text: and as soon as the rakers are moved back along the bottom of the pan, with
the rakers raised up therefrom, so that the rakers will have passed away from
over the mould 52, and descended the inclined plane 51, 50, then the work-
men proceeds to level and beat down the salt solidly into the spaces of the
mould, but with some excess of salt projecting above the level of the sides
of the mould and its partitions; and in order that the beating may be
more effectually performed, the mould is then lifted up and turned over to
enable the workman to repeat the beating in the opposite direction. The
aforesaid board 53, when placed beneath the mould, was made fast thereto by
a pair of hooked catches 54, 54 (Figures 8 and 10), at each end, so as to
form a temporary bottom to the mould 52; and after the mould has been
filled with salt, and that salt beat down at the upper side as aforesaid (but
before the mould is lifted up in order to be turned over), another like board
56 is placed over the beaten salt that is in the mould, and that board 56 is
made fast to the mould 52 with a pair of hooked catches 57, 57 (Figures 8
and 10), at each end. After the mould is turned over, the board 56 will
become the temporary bottom of the mould; and in order to facilitate the
said lifting up and turning over of the mould 52, it is suspended by means of
two pins 58, 58, Figures 9 and 10, which project out horizontally from each
end of the mould, and those two pins are caught by hooks at the lower ends
of two upright links 59, 59, Figures 8 and 10, which links hang down from
the two ends of a lifting bar 60, having a swivel eye 61 at the middle of its
length for a rope 62, which passes over a pulley 63, and by that rope 62 the
mould 52, with its two boards 53 and 56, is easily drawn up and suspended in
the manner shewn in Figure 10, and can then be turned over about its pins
58, 58, so as to bring the board 56 undermost; and that being done, the
whole is let down again by the rope 62 until the said board 56 rests on
the supports e, e, at the bottom a, a, of the pan, in the same manner as the
board 53 had previously done. Then the hooked catches 54, 54, are released,
and the board 53 removed, and the beating of the salt is completed, and suit-
able prints, with the name or device of the salt manufacturer, may be applied
and beaten into each of the squares of salt, or such prints may be formed on
the board 56. The mould being thus filled very solid with salt, and the
board 53 replaced and fastened, the whole is then drawn up again, as. in
Figure 10, and hoisted on to a truck or carriage on which the board 56 will
rest, and then the hooked catches 54, 54, and 57, 57, being released, the
board 58 is removed, and then the mould 52 is lifted off, leaving the salt in
six separate squares resting by themselves on the board 56, the insides of the
spaces in the mould being suitably tapered for so leaving the squares; and

page_text: after allowing due time for drainage of brine from the salt, the carriage (which
will hold the contents of several moulds) is wheeled onwards along suitable
rails into the salt-drying stove.
[And another part of my improvements in apparatus for manufacturing salt
consists in the means represented in Figures 11 and 12, Sheet III., for supplying
the fireplaces or furnaces of salt pans with regulated quantities of fuel to be
added to the fires at suitable intervals of time. B, B, in both Figures, are
the fire grates. A, Figure 12, is one end of the salt pan, a, a, being the
uppermost bottom thereof, with brine resting thereon, and F the lowerniost
bottom, with fresh water resting thercon, the spaces between the two bottoms
of A and F being for fresh water, and steam arising from it, as herein-before
described. But note, this part of my improvements is equally applicable to
common salt pans with only one bottom, such as F, with the brine resting
thereon, and no such bottom as a, a. E, Figure 12, is the usual entrance to
the fireplace for throwing in coals on to the firegrate, and which entrance is
usually closed by the fire doors. But according to this part of my improve-
ments there is a space left before that entrance E, and the fire doors are at F,
the said A space being comprised between the usual front wall G, and an addi-
tional front wall G. The lower part of the said space is a flat surface h of
brickwork supported on an arch, and conforming with the surface of the fire-
grate B; and K is a hopper-shaped receptacle for coals, with its lower end
over the said surface h, the said receptacle being included in the space
between the walls G and G'; and L is a slider or horizontal sluice fitted across
near the lower end of K, M being another like slider situated higher up
across the same receptacle K, and the space therein between the said two
sliders L and M is suitable for containing the regulated quantity of coals that
is to be put on the fire at one time. The coals (which must be in tolerably
small-sized pieces, or must be broken into such pieces) is supplied into the
upper part N of the receptacle or hopper K; and that may be done from
small waggons which run along a suitable railway situated over a row of fire-
places, and the coals in N rest upon the upper slider M, the lower slider L
being pushed into its place across the receptacle K, then the upper slider M,
being drawn out, will allow as much of the coals at N to descend and rest
upon the slider I as will fill the said space between L and M. Then M is
pushed in or closed, and after that the fire door or doors at F being opened,
the burning coals then on the grate are to be pushed back thereon (with a
suitable fireiron) towards the remote end of the grate, and then the slider L,
being drawn out and opened, will let down the said regulated quantity upon
the flat surface h, and then (before the fire door or doors at F is or are closed)

page_text: the said coals are pushed backwards from hon to the firegrate B with the said
fireiron, so as to give a feed to the fire thereon. The quantity of coals that
will thus be supplied to the fire will be the same at each time of feeding, and
the fire may be kept burning with regularity. The lower slider L is closed,
and then the upper slider M is opened, and then closed again after the space,
between the two sliders becomes filled with coals; and afterwards, when the
fire is to be fed again, the lower slider L is opened to let down the regulated
quantity of coals on h, as before, and so on for each time of feeding the fire.
Having now described my said improvements, I, the said George Ellins, do
hereby declare, that the new Invention whereof the exclusive use is granted
to me by the Letters Patent herein-before recited, consists in the following
particulars, that is to say :-
Firstly, in the improvement in manufacturing salt herein-before described,
and represented in Sheet I. of the Drawings hereunto annexed, of the appli-
cation of a current or of currents of, heated air to act beneath the bottom of a
salt pan or the bottoms of salt pans, or beneath a portion or portions of the
bottom or bottoms of such pan or pans, in order to communicate additional heat
to hot brine that is resting upon the said bottom or bottoms, such current
or currents of air being forced, by action of suitable blowing machinery, to pass
in small divided streams through heated pipes of iron inclosed in a hot-air
stove or oven, so that the air will become heated to a high temperature in a
similar manner to the hot blast for furnaces for smelting iron, but without the
contraction of passage and pressure of the hot air that is required for a blast,
and with part of the bottom of the salt pan forming a flat roof or top to the
said stove or oven, in order that the fire or fires therein may be operative to
give heat to the pan, in addition to such other fire or fires as may be requisite
for the heating thereof; and the air so heated being conveyed in a suitable
passage or passages beneath a portion or beneath portions of the bottom of a
salt pan having hot brine resting on the said portion or portions of that
bottom, and the other portion or portions of the said bottom having steam
applied beneath the same, in order to give some heat to the brine in the pan,
and that heat so communicated by the steam will be augmented by the
stronger heat communicated from the hot air, so as, by a two-fold communica-
tion of heat to the brine, to cause the same to boil and deposit crystals of
salt. The said current or currents of hot air, after having passed through the
said passage or passages beneath a portion or portions of the bottom of one
salt pan as aforesaid, may then escape into the flue or flues of an ordinary
drying stove for drying salt, or else, previously to so escaping, the said hot air
may pass onwards through the passage or passages of another second salt pan,

page_text: which may either have steam heat like the first or may be a simple salt pan
without steam heat; or the said current or currents of hot air, or a portion or
portion of that hot air, after having operated in manner aforesaid, or partly
operated in that manner within such passage or passages for communicating
additional heat to the brine, may then pass out from the said passage or
passages through suitable tubes, as herein-before described, so as to be emitted
in small streams beneath the surface of the same brine, in order to mix there-
with, and communicato further additional heat thereto, so that there will in
such case be a three-fold communication of heat to the brinc. And this first
part of my Invention is a combination, in manner aforesaid, of the means
herein-before described of obtaining hot air, and of applying that hot air either
in conjuction with steam heat for giving heat to brine by a two-fold or three-
fold communication of heat thereto, or, in some cases, applying such hot air
by itself, as herein-before described.
Secondly, in the improvement in apparatus for manufacturing salt herein-
before described and represented in Sheet II. of machinery for raking salt along
the bottom of a salt pan by means of a row of rakers which are adapted for
so raking the salt in either direction along the pan, and also for drawing the
salt up out of the brine in the pan, and depositing and accumulating that salt
upon a moveable table where the brine will drain from the said salt, and after-
wards, by movement of that table, the said salt can either be transfered into
a storehouse or loaded into a carriage or vessel for conveyance. And this
second part of my Invention is a combination of the various parts of the said
machinery for raking the salt, and drawing the same out of the brine, and of
the other parts for depositing and accumulating the said salt for draining, and
for afterwards transfering the salt to a warehouse, carriage, or vessel.
Thirdly, in the improvement in apparatus for manufacturing salt herein-
before described and represented in Figures 8, 9, and 10, Sheet III., of the
moulds or frames. Figure 9, for receiving salt, which is to be dried in
squares; and the means shewn in Figure 8 of filling the salt into those
moulds; and the means shewn in Figure 10 for removing the moulds out of
the
pan, and then transfering the squares of salt into the usual drying stove.
Fourthly, in the improvement in apparatus for manufacturing salt herein-
before described and represented in Figures 11 and 12, Sheet III., of the mode.
of supplying regulated quantities of fuel to the furnaces for salt pans, so as to
keep up regular fires, and avoid waste of fuel.
In witness whereof, I, the said George Ellins, have hereunto set my hand
and seal, this Twenty-first day of September. 1848.
GEORGE (Ls.) ELLINS.

page_text: AND BE IT REMEMBERED, that on the Twenty-first day of September,
in the twelfth year of the reign of Her Majesty Queen Victoria, the said
George Ellins came before our said Lady the Queen in Her Chancery, and
acknowledged the Instrument aforesaid, and all and every thing therein con-
tained and specified, in form above written. And also the Instrument
aforesaid was stamped according to the tenor of the Statute made in the
fifty-fifth year of the reign of His late Majesty King George the Third.
Inrolled the Twenty-second day of September, One thousand eight
hundred and forty-eight.