IMPROVE- MENTS IN THE MANUFACTURE OF SODA AND POTASH
Year: 1864

page_text: LETTERS PATENT to Andrew George Hunter, of Rockcliff Hall, near
Flint, in the County of Flint, Chemist, for the Invention of " IMPROVE-
MENTS IN THE MANUFACTURE OF SODA AND POTASH."
PROVISIONAL SPECIFICATION left by the said Andrew George Hunter
at the Office of the Commissioners of Patents, with his Petition, on the
17th November 1864.
I, ANDREW GEORGE HUNTER, of Rockcliff Hall, near Flint, in the County
of Flint, Chemist, do hereby. declare the nature of the said Invention for
"IMPROVEMENTS IN THE MANUFACTURE OF SODA AND POTASH," to be as follows:-
The object of my Invention is to effect the conversion of sulphate of soda
into caustic soda, or of sulphate of potash into caustic potash, by decomposing
sulphate of soda or sulphate of potash, by mixing therewith sufficient caustic
baryta to combine with the sulphuric acid it contains, whereby sulphate of
barytes is formed, and caustic soda or caustic potash liberated. The pro-
portions are about 4 parts of the sulphates with 3 parts of baryta.
I conduct this process by mixing well together solutions of caustic baryta
and of the sulphate to be operated upon, or by mixing caustic baryta with a
solution of the sulphate, or by mixing the sulphate with a solution of the
caustic baryta.
I remove the sulphate of barytes from the liquor by means of filtration or
subsidence and decantation, and after washing it to free it from adhering soda

page_text: or potash, or other matter, I employ it for similar purposes to those for
which native sulphate of barytes is used.
From the liquor I manufacture marketable caustic soda, or caustic potash ;
or I carbonate the liquor either by injection of or exposure to carbonic acid,
and manufacture from it carbonate or bicarbonate of soda or carbonate or
bicarbonate of potash.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Andrew George Hunter in the Great Seal Patent Office on
the 17th May 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANDREW
GEORGE HUNTER, of Rockcliff Hall, near Flint, in the County of Flint, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Seventeenth day of November, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Andrew George Hunter, Her special licence that I, the said Andrew
George Hunter, my executors, administrators, and assigns, or such others as
I, the said Andrew George Hunter, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
.“ IMPROVEMENTS IN THE MANUFACTURE OF SODA AND POTASH," upon the condition
(amongst others) that I, the said Andrew George Hunter, my executors or
administrators, by an instrument in writing under my, or their, or one of their
bands and seals, should particularly describe and ascertain the nature of the
said Invention, and in what manner the same was to be performed, and cause
the same to be filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Andrew George Hunter, do hereby
declare the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement:-
The object of my Invention is to effect the conversion of sulphate of soda
into caustic soda, or of sulphate of potash into caustic potash, by decomposing
sulphate of soda or sulphate of potash, by mixing therewith sufficient caustic

page_text: baryta to combine with the sulphuric acid it contains, whereby sulphate of
barytes is formed, and caustic soda or caustic potash liberated.
I conduct this process by mixing well together solutions of caustic baryta
and of the sulphate to be operated upon, or by mixing caustic baryta with a
solution of the sulphate, or by mixing the sulphate with a solution of the
caustic baryta. The proportions of the chemical ingredients mentioned vary
according to their chemical equivalents, which are well known to practical
chemists.
I remove the sulphate of barytes from the liquor by means of filtration or
subsidence and decantation, and after washing it, to free it from adhering soda
or potash, or other matter, I employ it for similar purposes to those for
which native sulphate of barytes is used.
From the liquor I manufacture marketable caustic soda or caustic potash ;
or I carbonate the liquor either by injection of or exposure to carbonic acid,
and manufacture from it carbonate or bicarbonate of soda, or carbonate or
bicarbonate of potash.
Having now described the nature of my said Invention, and the manner in
which the same is to be performed, I claim as my Invention and desire to be
secured to me by the herein in part recited Letters Patent, the "Improvements
in the Manufacture of Soda and Potash," by converting the sulphate of soda
or sulphate of potash into caustic soda or caustic potash by means of caustic
baryta; and the production of the carbonates or bicarbonates of soda and
potash from the caustic soda and caustic potash so manufactured, and the
production and utilization of the sulphate of barytes, substantially as herein
specified.
In witness whereof, I, the said Andrew George Hunter, have hereunto
set my hand and seal, this Fifth day of May, in the year of our
Lord One thousand eight hundred and sixty-five.
Witness,
ARTHUR CULLIN,
Solicitor,
53, Lower Dominick Street,
Dublin.
A. G. HUNTER. (L.B.)