IMPROVEMENTS IN THE MANUFACTURE OF SODA AND OTHER VALUABLE PRODUCTS FROM COMMON SALT
Year: 1839

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOSEPHI
HUNT, of No. 25, Dalston Terrace, in the County of Middlesex, Gentleman,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Seventh day of May, in the second year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Joseph Hunt, Her especial licence, full power, sole privilege and authority,
that I, the said Joseph Hunt, my exors, admors, and assigns, or such others
as I, the said Joseph Hunt, my exors, adiñors, or assign, 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, my
Invention of "IMPROVEMENTS IN THE MANUFACTURE OF SODA AND OTHER VALUABLE
PRODUCTS FROM COMMON SALT," in which said Letters Patent is contained a
proviso, that I, the said Joseph Hunt, shall cause a particular description of
the nature of my said Invention, and in what manner the same is to be
performed, 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.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Joseph Hunt, do hereby declare the nature of my said Invention, and tho

page_text: manner in which the same is to be performed, are fully described and ascer-
tained in and by the following statement thereof (that is to say) :-
My Invention relates, first, to a mode of manufacturing soda by triturating
blue lead with common salt (muriate of soda, or chloride of sodium.)
Secondly, to the treating of one of the resulting products of the first part
of the Invention with diluted sulphuric acid, and thereby obtaining a pigment
or vehicle for coloring matter used in painting.
Thirdly, to treating one of the resulting products of the first operation with
carbonic acid gas,
and thereby producing carbonate of lead.
And, fourthly, to the triturating zinc of commerce with common salt,
muriate of soda, or chloride of sodium, and treating the products of such
process in like manner to those wherein blue lead is employed.
And in order to give the best information in my power, I will proceed to
describe the processes as pursued by me in order to carry out my Invention.
DESCRIPTION OF PROCESSES.
I take any quantity of blue lead, reduced by cutting or otherwise into about
the size of swan. shot, and triturate the same with brine (solution of common
salt), whether the same be obtained from brine springs, from dissolving
common salt, or from sea water; I prefer the common salt to be in this
condition, though it may be thrown in amongst the lead in a dry state, and it
will obtain moisture from the atmosphere, or the same may be accomplished
by jets of steam. The trituration may be performed either by mechanically
causing the particles of lead to be moved about by stirring, or by causing the
vessels to move in such manner as to cause the portions of lead to move and
rub against each other. And I would here remark, that the process of
trituration of lead with various other fluids is not new, and is well understood,
and does not require to be further explained other than to state that it is
preferable to use shallow vessels, so that in the act of trituration the matters
under operation shall be as much as possible acted on by the atmosphere.
'The quantity of salt required in any of the above forms depends upon the
quantity of lead submitted to be acted upon by the trituration process, and to
the time it is being thus acted upon; an exact quantity is not, however, of
consequence, nor is an exact time material; but I find in practice that a con-
venient quantity of salt in any of the above forms is that which is equal to
about half an ounce of salt in a dry state to every pound weight of lead under
process, and the time for it to be under the process about twenty-four hours,
supposing the agitation of the particles of lead be well kept up. The products
I obtain by the above process are, first, soda in solution, in combination with

page_text: so much salt as has not been decomposed; and, secondly, a white substance.
I then with water wash away these products from the lead which has not been
acted upon;
I then proceed to separate the products, and further to act upon
them. I will first state how I proceed with the soda :-I allow the products,
which are now mixed together to settle; I then draw off the solution, and
with water wash the white substance which is deposited to obtain all the soda
from it; I then in any suitable vessel proceed to separate the salt from the
soda by evaporation, taking the salt out as it precipitates (which salt I again
use in the triturating or friction process with further quantities of metallic
lead); the soda I then evaporate to dryness in the state it then is (which is
partly caustic and partly a carbonate), or I submit it to be acted upon by
carbonic acid gas in any of the well-known ways, and thus obtain carbonate
of soda, which I either evaporate to dryness, or form into crystals, as may be
required, and as is well understood.
I will now state how I further proceed with the white substance; I have
two processes; firstly, I put into any suitable vessel and add to it proportions
of diluted sulphuric acid, and thereby obtain a subsulphate of lead to be used
for any purpose it may be required, but more particularly as a pigment or
vehicle for color, for which it is particularly well adapted; the vessel used for
this part of my process may be open or closed; if the former, the chlorine
which passes from the white substance will go off into the atmosphere; if the
latter, and the suitable pipes be added, the chlorine may be conducted into
vessels or chambers containing lime or other matter, and thus a chloride of
such substances will be manufactured; or by my second process, I take the
white substance and I evaporate it to dryness, then grind it in water between
stones; I then submit it to be acted upon by carbonic acid gas in any of the
usual well-known ways, and thus obtain the substance called carbonate of
lead, or white lead; it may be submitted to the influence of the carbonic acid
gas without first drying, but I prefer to dry it and grind it in water, as before-
stated.
Having thus described the nature of the Invention, so far as it relates to
making soda from common salt by triturating particles of lead therewith, it
only remains for me to add, that in carrying out the fourth part of my Inven-
tion, I pursue the same processes, substituting metallic zinc for the blue or
metallic lead, and products of soda will be obtained from the common salt,
and other products of the salt will be in combination with the zinc, which
being treated as above described, will produce valuable products applicable as
above described. I would remark, that I am aware that lead has been
triturated in pure water, and also in acidulated water, and I believe the

page_text: product has been treated with carbonic acid gas; I do not therefore claim the
treating the triturated products of lead with carbonic acid gas, but my Inven-
tion only relates to the treating the products of lead when obtained by
trituration with common salt; and I would have it understood that what I
claim is,-
First, the mode of making soda by triturating blue or metallic lead of
commerce with common salt, as above described.
Secondly, I claim the treating one product of the first process with diluted
sulphuric acid, and obtaining a pigment or vehicle for color, as above
described.
Thirdly, I claim the treating the one product (with carbonic acid gas) to
obtain carbonate of lead, as above described.
And, fourthly, I claim the obtaining soda and other valuable products from
common salt by treating it with zinc, as above described.
In witness whereof, I, the said Joseph Hunt, have hereunto set my
hand and seal, this Seventh day of November, in the year of our
Lord One thousand eight hundred and thirty-nine.