CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF SALT
Year: 1843

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BUSHBY GIBSON, of Nantwich, in the County of Chester, Esquire, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Twenty-fifth day of May, in the sixth year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said John
Bushby Gibson, my exors, admors, and assigns, Her especial licence, full
power, sole privilege and authority, that I, the said John Bushby Gibson,
my exors, admors, and assigns, and such others as I, the said John Bushby
Gibson, my exors, admors, or assigns, should at any time agree with, and
no others, from time to time and at all times thereafter during the term of
years therein expressed, should and lawfully might make, use, exercise, and
vend, within that part of Her Majesty's United Kingdom of Great Britain and
Ireland called England, Her Dominion of Wales, and the Town of Berwick-
upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS IN THE MANUFACTURE
OF SALT;" in which said Letters Patent there is contained a proviso, that I,
the said John Bushby Gibson, shall cause a particular description of the
nature of my said Invention, and in what manner the same is to be performed,
under my hand and seal, to be inrolled in Her said Majesty's High Court
of Chancery within six calendar months next and immediately after the date
of the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that the nature of my said Invention, and in what
manner the same is to be performed, are fully set forth and ascertained in and
by the following Specification thereof, reference being had to the Drawings
hereunto annexed, that is to say :-
My said Invention consists of seven different improvements in the manu-
facture of salt, whereof the description is as follows:-
The first of these. improvements consists in constructing salt pans, whether
made all of metal, or partly of metal and partly of other materials, of such an
increased depth in that part where the salt falls or is deposited, that the
operation may be continued for a time, limited only by that depth. According
to the common mode of manufacture, the salt is taken out of the pans every
day, by which a great loss of time is sustained, and the chrystals of the salt
have not time to acquire the degree of firmness and perfection which would
be imparted to them by their remaining a longer time in the pan. By making
the
pans, for example, at the back part six feet deep, they would not require
to be drawn or to have the salt taken out of them except about once in every
ten days.
Figure 1, of the Drawings hereunto annexed, is an elevation, and Figure 2
a plan, of a salt-making apparatus constructed in this improved manner.
A is the furnace; B is the part of the pan immediately over the fire, which is
made as usual, flat and shallow; C is a flue by. which the heat and smoke
pass to the chimney, and which is carried through the brine near to its top
surface; D is the bottom of the pan, which is made of any required depth,
from three feet upwards.
The second of my improvements consists in converting coarse-grained salt
into fine-grained salt of. superior value, by pulverizing or pounding the same
by means of rollers, crushers, or any other analagous mechanical contrivances;
when so pulverized it may be put in moulds and made of the usual form, or
may remain in the state known as "butter salt."
My third improvement consists in exposing brine to the action of hot air,
in the männer represented in the elevation, Figure 3; and Plan 4, of the
Drawings hereunto annexed. Air, heated by any well-known method, is forced
ór drawn into a tube. A, perforated with holes all round; through which holes
the hot air passes and fills the interior of the vessel B'; brine is kept con-
tinually dropping from the plate C, which is perforated for the purpose (except
at the part immediately over the pipe A), through the mass of hot air to the
bottom of the vessel B, whence it is conveyed by the pipe G to an evaporating
vessel, from which it is returned by the pump D to the plate C, to be again

page_text: heated as before. E is a pipe which conveys the steam and hot air, not taken
up by the brine in the vessel. B, to be applied elsewhere to the warming of
brine; F is an opening, with door, through which any salt which may be formed
in the vessel B may be withdrawn.
My fourth improvement consists in conveying steam, hot air, or hot water.
through brine by pipes, which are removable for the purpose of drawing out
the salt, cleaning or repairing them, whereas such pipes have heretofore been
always fixtures. The mode in which I effect this is by conveying the steam,,
hot air, or hot water from the boiler, furnace, or other generator through a
main pipe, which is placed out of the brine, to another pipe which is carried.
through the brine, to which second pipe are attached as many branch pipes as
may be thought desirable.
Figure 5, of the Drawings hereunto annexed, is a side view, explanatory.
of this arrangement of piping, and Figure 6 an end view. A is the main
steam pipe, which is placed out of the brine; B is the second pipe, which
is carried through the brine, and with which A communicates; from this
second pipe twelve smaller pipes a, a, a, branch off, forming one compart-
ment of piping. The ends of the second pipe B are inserted in stuffing
boxes, attached to a branch from the main pipe A, so that the whole com-
partment of pipes may hinge, as it were, in the stuffing boxes, and may.
with facility be raised from a horizontal position in the brine to a vertical one
out of it. C is a valve for shutting off the steam from any one compartment
of piping when it requires to be raised; E is a cock for escape of air; F, the
vessel containing the brine, and G the surface of brine.
My fifth improvement consists in a method of preventing to a certain
extent the formation and accumulation of pan scale in that part of the salt-
making apparatus exposed to the immediate action of the fire, and where
the principal injury is sustained. I accomplish this by making the part so
exposed of metal tubes of any form, size, or length (preferring the cylindrical),
and made perfectly smooth inside; at one end these tubes are affixed to the
front rim of the pan, and extend horizontally from the said rim over the fires
and through the fore bay or front wall of the furnace to the cistern.
Figure 7, of the Drawings hereunto annexed, is a sectional view of this.
arrangement. A is one of the tubes; to keep them free from pan scale I pass a
rod B through a stuffing box F, screwed to a plate attached to the front of the
cistern (G), and through the entire length of each tube; to this rod are affixed
by springs D, D, D, one or more cleansers C, C, C, (which may be likened
to one of the rings of a metallic piston divided into two or more parts); the

page_text: rod, with the cleansers so attached to it, may have either a reciprocating or a
rotary motion given to it by any suitable machinery. The springs are made
of sufficient length so that the whole of the interior surface of the tubes may
be exposed to their action. The necessary degree of pressure is imparted to
these springs by means of the adjusting screws E, E, E. By the action of the
cleansers the pan scale is prevented from forming in any quantity hurtful to
the tubes, and thus, much of the injurious consequences attendant on its
formation, according to the present construction of salt pans, is avoided. The
tubes are covered with a double or reverberatory arch of bricks I, I, (with an
air space J between), or other suitable material; a vessel K, containing brine,
may also be placed over the double arch to prevent any escape of heat, or such
a vessel may be placed immediately over the tubes without the intervention
of the double arch, the tubes intervening between such vessel and the fire
preventing the intensity of the fire from acting on it. By affixing a valve to
the rod B, and another to any part of the cistern G which is in communication
with the salt pan, circulation in the brine may be produced, so that the hotter
brine may be made to pass through the tubes into the salt pan and be replaced
by cooler brine brought from the pan to the cistern. The plate in the front of
the cistern G, to which the stuffing box F is attached, covers a hole large
enough to admit of the cleansers being drawn out for repair, or other purposes;
L is a brick arch, which protects the joint connecting the end of the tubes
with the salt pan from the action of the fire; M is the furnace; N, the ash-
pit; Q, a friction roller to sustain the rod B in a horizontal position; P, P, the
level of brine in the main pan tubes and vessel: Instead of the cleansers being
worked in a horizontal position, they might, by an easy change in the arrange-
ments, be made to work vertically, but I prefer placing them in the manner I
have just described.
My sixth improvement consists in constructing salt pans bottoms of metal
plates, either entirely cast, or partly cast and partly wrought, and making these
plates either flat or arched, or partly flat and partly arched, whereby the
troughing, so much complained of as forming receptacles for the earthy and
other impurities precipitated from the brine, which are destructive of the pan
bottoms, is prevented. The plates may be joined by means of flanges, screw
pins, rivets, or welts, but the last-named mode I prefer, placing the welts on
the upper surface of the bottom of the
pan.
Figure 8 of the Drawing hereunto annexed is a transverse section of a salt
pan of two fires, partly flat and partly arched, the arches being of cast metal,
and the flat parts of wrought.

page_text: tube
My seventh improvement consists of the method of supplying a pan'
with
heated brine during the process of evaporation, represented in Figure 9 of
the Drawings hereunto annexed. A is the furnace; B, the ash-pit; C, a
or flue leading from the furnace; D is the pan which is filled
with brine; when full, the brine is allowed to pass through the valve G into
a trough E, perforated with holes, through which it falls on the heated
flue or tube C immediately under, where it remains till converted into salt;
F is a well for the reception of the salt made in the pan D; H represents
the level of brine in the pan and trough; I is a pipe to supply the pan with
brine.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that what I claim as of my
Invention is,
First, the constructing of salt pans of such an increased depth at the flue
end, where the salt chiefly falls or is deposited, as may ensure the advantages
before specified.
Second, the mode herein-before described of converting coarse-grained salt
into fine.
Third, the passing of the brine through hot air, whether this is effected by
the brine falling freely through the hot air, in manner before described, or by
any equivalent method, such as the ejection of the brine in jets into the midst
of the hot air, or the conducting of it through it by means of pipes.
Fourth, the conveying in manner before described of steam, hot air, or hot
water through the brine by means of pipes which can be removed and replaced
at pleasure, instead of being fixed, as asual.
Fifth, the preventing, in manner and to the extent before described, of the
formation and accumulation of pan scale.
Sixth, the prevention, in manner before bescribed, of the troughing of the
bottoms of salt pans.
And, seventh, the mode herein-before described of supplying pans with
heated brine during the process of evaporation.
In witness whereof, I, the said John Bushby Gibson, have hereunto set
my hand and seal, this Twenty-fourth day of November, One thousand
eight hundred and forty-three.
JOHN BUSHBY (L.S.) GIBSON.

page_text: AND BE IT REMEMBERED, that on the Twenty-fourth day of November,
in the year of our Lord 1843, the aforesaid John Bushby Gibson came before
our said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Enrolled the Twenty-fifth day of November, in the year of our Lord One
thousand eight hundred and forty-three.