IMPROVEMENTS IN THE MANUFACTURE OF SODA
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
JOSEPH CHARLES SHERIDAN, of Ironmonger Lane, in the City of London,
Chemist, 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-first day of August, in the first year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Joseph Charles Sheridan, Her especial license, full power, sole privilege, and
authority, that I, the said John Joseph Charles Sheridan, my exors, admors,
and 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 law-
fully 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;" in which said Letters Patent is contained a proviso
that I, the said John Joseph Charles Sheridan, 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
John Joseph Charles Sheridan, do hereby declare the nature of my Invention,

page_text: and the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, reference being had to
the Drawing hereunto annexed and to the figures and letters marked thereon,
that is to say:-
My Invention of "Improvements in the Manufacture of Soda" consists in
procuring soda by a decomposition of common salt, such decomposition being
produced by causing the salt, when in a state of vapour, to come in contact
(at the temperature of a bright red heat) with the steam of water, or with
hydrogen (also at a very high temperature.
I carry these improvements into effect by the following means:-I use two
kilns similar to a potter's oven, and I prefer the following dimensions and
shapes. The internal part of one these kilns A, B, C, D, is built in the form
of a cone and with fire-bricks; I prefer the Newcastle white fire-brick as
capable of sustaining a much greater heat. The walls or sides of this
cone to be four inches in thickness, the basis of this cone to be ten feet
feet in diameter, and the cone to be ten feet high, and the summit
to be six inches in diameter. This cone is so constructed that there is
an internal base or bottom about four feet above the basis, as described in
the Drawing. The object of this is to enable the flue to pass under the place
where the salt is put to be heated. The internal cone of the other kiln
a, b, c, d, is constructed of the same shape and dimensions and on the same
level on the summit of the first cone, and communicating with the interior of
the same, one end of a cast or wrought-iron tube T, T, T, T, six inches in
diameter is fixed, and establishes a communication between the two internal
cones; the iron pipe by means of a flanch is fixed to the top of the second cone,
and is prolonged to within four feet from the bottom..
The cones A, B, C, D, a, b, c, d, are surrounded by other cones A', B', C', D',
a, b, c, d, also built in fire brick, and embracing the whole at one foot
from the side of the internal cones. Round the sides of each of these second
cones six furnaces are built on the level ground, as indicated by the plan, and
marked F, H, O, f, h, o, three feet in height, and two feet by two feet square.
The frame and smoke of these furnaces are made to pass round the internal
cones A, B, C, D, a, b, c, d, so as to bring them to the necessary degree of
heat. It is necessary also to have three flues under the bottom of the first
cone A, B, C, D, establishing a communication from side to side six inches
below the bottom. These flues should be six inches wide, and six deep.
These cones A, B, C, D¹, a, b, c, d, not only surround the internal
ones, but must also surround the iron pipe so as to keep the latter at the

page_text: same degree of heat as the internal cones, and a chimney two feet square,.
supported below, is fixed above the iron pipe at Z, to carry off the smoke of
both kilns.
The cones A, B, C, D, a, b, c¹; d', are now surrounded by two others.
M, M, M, M, m, m, m; m, four feet from the cone A, B, C, D, a², b, c, d,
closed at the top. These may be built in common brickwork, as the object of
these last cones is to guard the others against the cold of the atmosphere.
A double man-hole N with sides is made so as to give an opening through
the cone A, B, C, D, to the cone A, B, C, D. Its dimensions must be one
foot by one foot six inches, and it is made of cast or wrought iron, with a door.
opening on the outer circumference of the cone A¹, B¹, C¹, .D¹.
}
An iron pipe P, six inches in diameter and eight feet long, is fixed on the
top of the second kiln, communicating with the internal cone. Another pipe
S, S, S, two inches in diameter, made of cast or wrought iron, communicating.
with a steam boiler, and having a cock to it, to regulate the injection of
steam, as herein-after mentioned, passes through the three cones of the second
kiln. This completes the construction of my apparatus.
I will now describe the mode of working it. The small furnaces are filled
with coals, and lighted. The inner cones are soon brought to a requisite
heat. Common salt in the quantity of one ton is gradually thrown into the
cone A, B, C, D, through the man-hole N. The heat volatilizes it, and in the
state of vapour it finds its way along the iron tube T, T, T, into the cone
a, b, c, d, which like the other is kept at a bright red heat. A current of
steam is then introduced through the pipe s, and brought into contact with
the vapour of the salt; the latter is decomposed, the oxide of sodium or
caustic or pure soda precipitates to the bottom, whilst the muriatic acid
formed by the chlorine of the salt and the hydrogen injected or obtained from
the decomposition of the water, as carried off through the pipe P into the
atmosphere or into a condenser.
The soda is taken out when it has filled the bottom of the internal cone to
the depth of three feet six inches, through the man-hole V, and the apparatus
is charged in the manner before described.
Instead of the steam of water, a current of hydrogen gas introduced in the
same manner will produce similar results.
Now I do not claim as my Invention any separate part of this apparatus,
such as kilns, furnaces, flues, pipes, &c., nor do I claim as my Invention the
separate application of any of these. But I do claim as my Invention the
procuring soda by the decomposition of common salt, caused by bringing the

page_text: salt when in a state of vapour to come in contact (at the temperature of a:
bright red heat,) with the steam of water, or with hydrogen at a very high.
temperature.
In witness whereof, 1, the said John Joseph Charles Sheridan, have
hereunto set my hand and seal, this Twenty-eighth day of February, 5
One thousand eight hundred and thirty-eight.