IMPROVEMENTS IN THE MANUFACTURE OF OXALIC ACID AND SALACETOCELLA
Year: 1836

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BARSHAM, of Stepney Causeway, in the County of Middlesex, Oxalic Acid
Manufacturer, send greeting.
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twentieth day of February in the sixth year of His reign,
did, for Himself, His heirs and successors, give and grant unto me, the said
John Barsham, His especial license, full power, sole privilege and authority,
that I, the said John Barsham, my exors, adñors, and assigns, or sucli
others as I, the said John Barsham, my exors, adñiors, 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, my Invention of "IMPROVEMENTS IN THE MANUFACTURE OF OXALIC
ACID AND SALACETOCELLA;" in which said Letters Patent is contained a pro-
viso, that I, the said John Barsham, shall cause a particular description of the
nature of my said Invention, and in what manner the same is to be per-
formed, to be inrolled in His 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 Barsham, do hereby declare the nature of my said Invention, and the
manner in which the samo is to be performed, are fully described and ascer-
tained in and by the following statement thereof, reference being had to the

page_text: Drawing hereunto annexed, and to the figures and letters marked thereon,
that is to say:-
According to the ordinary process of manufacturing oxalic acid, and
salacetocella, that portion of the process which relates to the making of the
oxalic acid is performed in open vessels which are kept heated by a warm
water bath, as is well understood, and the vapours evolved from the materials
or ingredients put into such open vessels, pass into the atmosphere of the room
or building in which the manufacture is carried on; and such vapours being of
a deleterious nature renders this process very injurious to the health of the
persons engaged in such manufactory, and at the same time is justly considered
a nuisance to the surrounding neighbourhood, in addition to the injurious
results above mentioned, which are consequent on the ordinary process of
manufacture the vapours are lost. Now the object of my Invention is to con-
duct that part of the process of manufacturing oxalic acid and salacetocella,
which relates to the making of the oxalic acid (whether to be used as oxalic
acid, or, when the process is to be carried further, in order by the usual and
well known means to produce salacetocella) in closed vessels in connection
with receivers and condensers, by which the vapours evolved in the process of
making the oxalic acid are condensed and collected again to be used, and hence
is prevented the deleterous effects formerly consequent on such vapours passing
into the atmosphere.
DESCRIPTION OF THE DRAWING.
Figure 1 represents part of a series of vessels arranged and constructed in a
suitable manner for performing my Invention; Figure 2 shows a side view of
one of the retorts and its receiver; in each of these Figures the same letters
indicate similar parts a a, being the vessels which, for distinction, I will call
the retorts, into these vessels the ingredients (similar in every respect to those
heretofore put into the open jars or vessels for making oxalic acid) are to be
introduced at the opening b. The internal construction of the retorts a will
more readily be understood by an examination of Figure 3, which is a section
of one of these vessels a, and by this Figure it will be seen that all around
the interior of each of the retorts a there is a trough into which fall any of the
vapours which may condense in the vessels a, and the same is thus prevented"
returning into the ingredients, but flows off from the vessel a through the tube
c into the vessel d, which I call the receivers, which are cylindrical vessels
closed at both ends, but having each five opening e, e, f, f, and g; the openings
e, e, are to receive the ends of the tubes, the openings f. f, are for the purpose
of receiving the bent tubes h, h, by which the receivers d are connected one to
the other, and hence any uncondensed vapours from the retorts a, a, may pass

page_text: from receiver to receiver and thence to other vessels or condensers hereafter
described. The opening g is to allow of a syphon being introduced for the
purpose of withdrawing the contained fluid from time to time when there is a
quantity accumulated; at other times the opening g is to be kept close with a
cover and luted with clay to prevent the escape of vapour; i is an opening in
each retort a, for receiving a syphon to draw off the liquor (when there is no
longer any gas evolved therefrom, which will readily be ascertained by removing
the cover of the opening i from time to time) into open shallow earthenware
pans about five inches deep, fifteen inches wide, and thirty inches long, in order
to crystalize the liquor thus produced, which will readily be performed by
placing the shallow vessels in warm baths, and bringing the liquor to the state
for producing the crystal desired, and complete the process precisely as if the
process had been performed in open jars or vessels as heretofore practised. j is
what I call the general receiver, and is connected by the pipe or tube K to the
receivers d, consequently any vapour which may be uncondensed will pass into
the vessel j, and from thence through a series of condensers 7, which are
cylinders closed at top and bottom, but having openings to connect one to the
other by pipes m, and each has also an opening n to receive a cock for drawing
off the liquor condensed therein. The number required of these condensers
will depend on the number of the retorts a; but I have found that twenty-
four condensers are fully sufficient for fifteen retorts a, and it should be
remarked that one of the openings m, to the last condenser is left open to the
atmosphere in order to keep up sufficient draft in the various vessels, and
induce the vapours to pass in that direction; at the same time care should be
observed that there are a sufficient number of condensers l, fully to effect a
condensation of the vapours from the retorts a, and thus prevent the same
passing into the atmosphere. I would hero remark that I have found it
advantageous to cause steam of about thirty pounds pressure to the square inch
from a boiler to enter by a small pipe (about one quarter of an inch bore,
having a stop cock) into the general receiver j, and also to cause the vapours
generated in cast-iron retorts in which salpetre is heated to a red heat to pass
by another pipe having a stop cock into the general receiver j; by this means
the various vapours in the vessel j will be more readily condensed, and the acid
drawn therefrom and from the condensers / will be stronger or of greater
specific gravity, and it will readily be ascertained when the steam is flowing
too slow or in too small a quantity by opening the cover of the condenser / next
to the general receiver, and if the gas proceeding therefrom is very strong the
stop cock is to be opened somewhat more; by this means a workman will
readily adjust the quantity of steam.

page_text: Having thus explained the nature of the apparatus used by me, and which
I have found most advantageously to perform my Invention, I would remark
that the whole of the vessels and pipes are constructed of stone pottery ware.
I will now explain the manner in which I perform the process of making tho
oxalic acid, whether it be for the purpose of making salacetocella or to be
used as oxalic acid. Into each of the retorts I put from ten to fifteen gallons
of the ingredients as usually employed in making oxalic acid, when perform-
ing the process according to the old manner of working in open vessels. The
retorts a are then to be covered, and all the joints and covers luted and well
closed, so that there will then be only an opening uncovered at the last of
the condensers 7. The retorts a, being in a water bath similar to that used
when open vessels are employed, the vapours rising in the retorts a will in
some degree be condensed in those vessels, and the remainder will pass on
and be condensed in the receivers or in the condensers as has been explained.
Having now described the nature of my Invention and the manner of
carrying the same into effect, I should remark that I lay no claim to the
vessels here shown and described in their separate condition; neither do I
confine myself to the shapes or dimensions shown. But I do hereby declare
that my Invention consists in making oxalic acid in a series of closed vessels
a, a, with receivers and condensers as above described, whether the Invention
be performed as the preliminary process in making salacetecella, or only for
producing oxalic acid to be used as such.
In witness whereof, I, the said John Barsham, have hereunto set my hand
and seal, this Nineteenth day of August in the year of our Lord One