IMPROVEMENTS IN THE MANU- FACTURE OF NITRIC AND NITROUS ACIDS, AND OTHER NITROGENOUS COMPOUNDS
Year: 1862

page_text: LETTERS PATENT to James Webster, of Birmingham, in the County of
Warwick, Engineer, for the Invention of "IMPROVEMENTS IN THE MANU-
FACTURE OF NITRIC AND NITROUS ACIDS, AND OTHER NITROGENOUS COMPOUNDS."
Sealed the 11th March 1868, and dated the 15th September 1862.
PROVISIONAL SPECIFICATION left by the said James Webster at the
Office of the Commissioners of Patents, with his Petition, on the 15th
September 1862.
I, JAMES WEBSTER, of Birmingham, in the County of Warwick, Engineer,
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF NITRIC AND NITROUS ACIDS, AND OTHER NITROGENOUS
COMPOUNDS," (to be as follows, that is to say):-
I generate binoxide of nitrogen gas from nitrous acid, or any other body
containing binoxide of nitrogen gas. In using nitrous acid I cause the acid
to be run into a suitable retort or vessel red hot, and filled with pumice-
stone, or any other similar material that will not be decomposed whilst in a
red-hot state by the acid. The nitrous acid being run or dropped upon the
red-hot pumicestone will be converted into binoxide or deutoxide of nitrogen
gas NO. This gas is conveyed to a vessel or generator provided at a suitable
position at the side, and near its bottom, with a draught hole or regulating
damper, the top of the vessel being furnished with an outlet into a chimney to
cause a draught; or this draught may be ensured by any other suitable means.
One generator or more may be used according to circumstances. The

page_text: binoxide of nitrogen gas, NO³, is conveyed to the generator from the retort by
a suitable pipe, having its ingress into the generator at or near the bottom of
the generator, and opposite the draught pipe, to meet the current of air drawn
through the draught pipe. The binoxide of nitrogen gas, NO², coming in
contact with the air instantly absorbs oxygen from the atmosphere, and
becomes nitrous acid NO'. The generator is provided with a number of trays
or divisions, upon which is placed material (varying, as will be presently
described,) moistened with water, for instance. If I require to make nitric
acid and nitrous acid, the material upon the tray will be gravel, sand, broken
pumicestone, or any other material upon which the acid will not act; this is
to be moistened with water. If I require to make any particular nitrate, I
place upon these trays the suitable caustic material moistened with water
instead of the gravel or sand; thus, if I am making nitrate of potass, I uso
the caustic of potass damped with water upon the trays; for the nitrate of
soda I use caustic of soda, and so on, taking care that in this latter instance
the caustic of soda should be mixed with gravel or sand to provent its
obstructing the passage of the gas by its density, and to offer a large surface
for the action of the gas. The carbonates, either alone or mixed with the
caustics, may be used if preferred. The binoxide of nitrogen gas by its
passage through the generator when using gravel or sand is decomposed by
the water into nitric acid, and perhaps some nitrous acid, and a portion of
binoxide also remains, which may be further taken up by passing through
another generator. In like manner the binoxide of nitrogen gas in its passage
through the generator over the caustics or carbonates named is decomposed
by the water, and becomes the nitrate of the base employed. The mode I
profer in making the nitrates is to withdraw the nitric and nitrous acid from
the condenser in a liquid state, and pour it upon the carbonate or caustic
base; this may be done by any of the ordinary operations in use.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Webster in the Great Seal Patent Office on the 30
12th March 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
WEBSTER, of Birmingham, in the County of Warwick, Engineer, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters 35
Patent, bearing date the Fifteenth day of September, in the year of our Lord

page_text: One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said James Webster, Her special licence that I, the said James Webster, my
executors, administrators, and assigns, or such others as I, the said James
Webster, 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 Islo of Man, an Invention for "IMPROVEMENTS IN
THE MANUFACTURE OF NITRIC AND NITROUS ACIDS, AND OTHER NITROGENOUS
COMPOUNDS," upon the condition (amongst others) that I, the said James
Webster, by an instrument in writing under my hand and seal, should par-
ticularly 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 James Webster, 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 fol-
lowing statement, that is to say:-
In carrying out my Invention I first generate the binoxide of nitrogen gas
from nitrous acid, or any other body containing the binoxide of nitrogen gas.
If using nitrous acid, I cause tho acid to be run into a suitable retort or
vessel red-hot, and filled with pamicestone, or other similar material that will
stand a red heat without being decomposed by the acid. The nitrous acid
being run or dropped upon the red-hot pumicestone becomes converted into
binoxide or deutoxide of nitrogen gas, NO. This gas is then conveyed to a
vessel or generator, or condenser furnished at a suitable position at the side,
and near the bottom with a draught hole or regulating damper, and at the top
with an outlet into a chimney to obtain a draught; or the draught may be
insured by other means if required. One or more of these generators or
condensers may be employed according to circumstances. The binoxide of
nitrogen gas, NO³, may be conveyed to the generator from the retort by a pipe
having its ingress to the generator at or near the bottom of that vessel, and
opposite the draught pipe, to meet the current of air passing through the
draught pipe. The binoxide of nitrogen gas, NO, coming in contact with the
air instantly absorbs two of oxygen from the atmosphere, and becomes nitrous
gas, NO. The generator contains a number of trays or divisions, upon which
are laid the following materials (varying according to circumstances):-Thus,

page_text: if I require to make nitric acid and nitrous acid, the materials upon the trays
will be gravel, sand, broken pumicestone, or other similar substances upon
which the acid will not act, damped with water. If I require to make any
particular nitrate, I place upon the trays, instead of the substances before
named, the caustic base of such nitrate damped with water; thus if I wish to
make the nitrate of potass, I employ the caustic of potass; if the nitrato of
soda, the caustic of soda, and so on, only in the case of using caustic of soda,
care must be taken that it be mixed with gravel or sand to prevent its offering
by its density any obstruction to the passage of the gas, and to afford a larger
surface for the action of the gas. Carbonates either alone or mixed with the
caustics may also be employed if preferred. The binoxide of nitrogen gas in
its passage through the generator when gravel or sand only is upon the trays
becomes decomposed by the water into nitric acid, and perhaps some nitrous
acid; whilst a portion of the binoxide also remains, which may be further
taken up by passing it through another generator. In like manner the
binoxide passing over caustics or carbonates in the generator is decomposed
by the water, and becomes the nitrate of the base employed. The preferable
course in making the nitrates is to withdraw the nitric and nitrous acid from
the generator or condenser in a liquid state, and pour it upon the carbonate
or caustic base, which may be done by any of the ordinary operations in use.
In making nitric or nitrous acids from the nitrates of soda or potass, I
employ a fire-clay retort fixed horizontally, and similar to a gas retort, with
an opening at the rear, furnished with a pipe to carry off the gases or vapours
to the generator or condenser before named. The hinder half of this retort is
filled with fire-brick, laid open, or pigeon-hole fashion, through which the gas, as
it is given off, passes to the condenser. At the fore end of the retort is fitted a
valve or regulating damper, so that the admission of the atmosphere may be
regulated during the working of the retort, which, whilst at work, requires to
be kept at a bright red heat. In preparing the charge I mix the nitrate
(whether of soda or potass) with three times its weight of broken pumice-
stone, or other like substance, to avoid the nitrate being in too fluid a state,
and also to form a porous base for the heat to act upon. This charge being
placed in the retort, the gas or vapour evolved passes through the perforated
brickwork at the back of the retort, and through the exit pipe to the con-
denser. When the retort is charged the regulating damper is to be opened,
when a current of air will be drawn into the retort, which will pass along with
the gas evolved from the nitrate through the open brickwork to the condenser.
The charge having been worked off, which will take for a weight of two
hundred pounds about four hours, the residue is to be withdrawn from the

page_text: retort and thrown into water, the pumicestone will precipitate, and the water
will withdraw the base of the salt employed, which may be boiled down for
caustic soda or potass, as the case may be, and the pumicestone or other
similar substance used after having been dried may be mixed with a fresh
proportion of nitrate, and used over again any number of times, replacing the
slight waste that occurs with fresh pumicestone.
Having thus described the nature of my said Invention, and the manner in
which the same is to be performed, I claim without limiting myself to these
precise details, the improvements in the manufacture of nitric and nitrous
acids, and other nitrogenous compounds, substantially as herein more fully set
forth and specified.
In witness whereof, I, the said James Webster, have hereunto set
my hand and seal, this Eleventh day of March, in the year of our
Lord One thousand eight hundred and sixty-three.