AN IMPROVED METHOD OF MANUFACTURING SALT
Year: 1830

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN,
BRAITHWAITE and JOHN ERICSSON, of the New Road, in the County of
Middlesex, Engineers, send greeting.
'WHEREAS His present most Excellent Majesty King George the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Twenty-seventh day of February, in the eleventh year of
His reign, did, for Himself, His heirs and successors, give and grant unto
us. the said John Braithwaite and John Ericsson, His especial licence that we,.
the said John Braithwaite and John Ericsson, our executors, administrators,
and assigns, or such others as we, the said John Braithwaite and John Ericsson,,
our executors, administrators, or assigns, should at any time agree with,
and no others, from time to time and at all times during the term of
years therein expressed, should and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, and,
also in all His said Majesty's Colonies and Plantations abroad, our Invention,
of "AN IMPROVED METHOD OF MANUFACTURING SALT;" in which said Letters.
Patent is contained a proviso obliging us, the said John Braithwaite and.
John Ericsson, by an instrument in writing under our hands and seals, or
under the hand and seal of one of us, particularly to describe and ascertain
the nature of our said Invention, and in what manner the same is to be
performed, and to cause the same to be enrolled in His said Majesty's High
Court of Chancery within two calendar months next and immediately after the
date of the said 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 in compliance with the said proviso, we, the said
John Braithwaite and John Ericsson, do hereby declare the nature of our
said Invention to consist in heating the brine from which salt of any required
quality is to be manufactured in a close boiler to a degree of temperature
above that necessary to produce the same quality of chrystalization by the
ordinary method, and also while the said brine is under pressure, in such
manner as to prevent any chrystalization or precipitation of salt in the boiler
in which it is so heated, and thence running it into large open shallow vats or
vessels, which we call evaporators, elevated above the boiler, and not acted
upon by the fire, where the aqueous particles being allowed to evaporate, and
the brine becoming of a lower temperature than that in the boiler, the salt
chrystalizes and precipitates to the bottom of the vat, by which improved
method of manufacturing salt we prevent the formation of what is usually
called pan scratch or pan crust, and effect an important saving in fuel.
And, in further compliance with the said proviso, we, the said John Braith-
waite and John Ericsson, do hereby describe the manner in which our said
Invention is to be performed by the following description thereof, reference
being had to the Drawings annexed, and to the figures and letters marked
thereon, that is to say:-
DESCRIPTION OF THE DRAWING.
Figure 1 is a plan of our said Invention. A is a boiler with parts repre-
sented as broken away, the better to shew its interior arrangement; B repre-
sents the fire-bars; C, C, the furnace doors; D, D, D, D, is the flue, with
cleansing doors as at E, through which to clean it out; F is a manhole; G is
the end of the flue which goes into the chimney; H is a supply pipe to feed
the boiler with cold brine; I is a cylinder fitted on to the top of the boiler for
purposes herein-after explained; J is a driving pulley to turn a shaft or
spindle working within the cylinder, to be also herein-after explained; K is a
_conduit pipe through which the heated brine from the boiler, after having been
brought into the cylinder I, runs into L, M, which is a large shallow vat or
vessel, called by us the evaporator, with a longitudinal division at O, and a
transverse one at P, the use of which divisions will herein-after be more par-
ticularly explained; Q, R, and S are float boards, to limit the evaporating
surface of the brine in the evaporator; T is a pipe serving to connect the
evaporator with the boiler, and leading from the evaporator to the bottom of
the boiler.
.
Figure 2 is a section of this pipe, as also of the boiler, and of the
side M of the evaporator, supposed to be taken from a to e (of Figure 1),

page_text: shewing the course which the brine is compelled to take under the transverse
division P. The object of this division, and of the well W, is to prevent the
salt which is forming in the evaporator from being carried into the boiler.
Figure 3 is an end view of the boiler and evaporator; and, as the same
letters are used to denote similar parts in all the Figures, it will only be
necessary to state that X is a second manhole in the boiler, and then refer to
the explanation of the other Figures to explain those parts in this Figure
which are similarly lettered.
Figure 4 is a section of the boiler, the cylinder I, the pipe K, and the side
L of the evaporator, supposed to be taken from C to r (of Figure 1); and it
will be seen that this side of the evaporator is also provided with a well V,
but without any transverse division. N is a spindle, to be driven round by
the pulley J, carrying on its lower end the vanes or fans Y, Y, Y, Y, and
supported on the step Z. This step is fixed to a bar that stands across the
aperture in the top of the boiler, which aperture communicates with the
cylinder I above it. U, U, is a float board, to prevent as much as possible
any evaporation taking place except in the evaporator.
The mode of operating with the apparatus berein-before described is as
follows: The apparatus being filled with brine, as shewn in the Drawing, and
a fire being lighted in the furnace, the column of brine in the cylinder I will
keep the brine in the boiler constantly under pressure, and thus it may be
always heated to a temperature higher than that in the evaporator, while, the
boiler being completely filled, no evaporation can take place therein, and con-
sequently no salt will be formed there to become pan scratch or pan crust.
When the brine in the boiler begins to heat, the fans Y must be turned by
means of the pulley J and a driving strap, when a portion of brine will be
displaced, which will pass through the pipe K into the evaporator; and, the
quantity so displaced being replaced by a portion out of the boiler, a corre-
sponding portion will flow from the evaporator into the boiler through the
pipe T, and thus a constant circulation of brine will be kept up, which, as soon
it flows beyond the float board Q, where evaporation first takes place, will
begin to deposit salt, which may be raked up in the ordinary way. As the
quantity of brine in the apparatus diminishes by evaporation, cold brine is to
be admitted to the boiler through the feed pipe H; and it is only necessary
further to observe that the temperature required for the particular quality of
salt to be produced must be regulated by the extent of evaporating surface
exposed in the vat or evaporator.
Now whereas other formed boilers and evaporators may be used, and the
contrivance for raising the brine from the boiler may be a pump or other

page_text: known engine; but whereas we claim as our Invention the manufacturing of
those qualities of salt the variety of which depends upon the temperature at,
which the chrystal is. formed by heating brine in a close boiler, under pres-
sure, to a degree of heat above that which would be required to form the same
quality of salt by the ordinary method, and then causing such brine, so heated!
as aforesaid, to pass from the close boiler into an open vessel, for the purpose:
of evaporation at a distance from and not acted upon by the fire, where the
required temperature is obtained, and thence, when too much cooled to:,
deposit salt of. the quality required, to return into the boiler to be again heated
to its former temperature, and' again passed into the open vessel, thus keeping
up a constant circulation of brine through the close boiler and open vessel,
and a consequent constant deposit of salt; and such our Invention being, to
the best of my knowledge and belief, entirely new, and never before used
within that part of His said Majesty's United Kingdom of Great Britain and -
Ireland called England, His Dominion of. Wales, or Town of, Berwick-upon-
Tweed, nor in any of. His said Majesty's Colonies or Plantations abroad, we, :
the said John Braithwaite and John Ericsson, do hereby declare this to be
our. Specification of the same, and that we do verily believe that our said
Specification doth comply in all respects fully, and without reserve or disguise,...
with the proviso in the said herein-before in part recited Letters Patent con-
tained; wherefore we do hereby claim to maintain exclusive right and privilege
to our said Invention...
In witness whereof, I, the said John Braithwaite, have hereunto set my
hand and seal, the Twenty-sixth day of April, iu the year of our Lord
Que thousand oight hundred and thirte
JNO BRAITHWAITE. (L.S.)
AND BE IT REMEMBERED, that on the same Twenty-sixth day of '
April, in the year above mentioned, the aforesaid John Braithwaite came
before our Lord the King in His Chancery, and acknowledged the Specifi-
cation aforesaid, and all and every thing therein contained, in form above:
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute in that case made and provided.
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