IMPROVEMENTS IN THE MANUFACTURE OF NORD- HAUSEN OIL OF VITRIOL
Year: 1875

page_text: LETTERS PATENT to William Stevens Squire, Manufacturing Chemist,
of 37, Acacia Road, St. John's Wood, in the County of Middlesex,
for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF NORD-
HAUSEN OIL OF VITRIOL."
Scaled the 14th March 1876, and dated the 18th September 1875.
PROVISIONAL SPECIFICATION left by the said William Stevens
Squire at the Office of the Commissioners of Patents, with his
Petition, on the 18th September 1875.
I, WILLIAM STEVENS SQUIRE, Manufacturing Chemist, of 37, Acacia
Road, St. John's Wood, in the County of Middlesex, do hereby declare
the nature of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE
OF NORDHAUSEN OIL OF VITRIOL," to be as follows:-
I take ordinary sulphuric acid, as concentrated as possible, and cause
the vapour of it to pass over a highly heated surface, and for this
purpose I prefer to use a platinum tube set in a furnace and filled with
either platinum foil or some porous substance such as pumicestone.

page_text: By these means the sulphuric acid is decomposed into water and
sulphurous acid and oxygen in equivalent proportions. I then dry the
gases thus obtained by causing them to pass through or over concen-
trated sulphuric acid, and then submit the dry sulphurous acid and
oxygen to the action of some substance, which at a low red heat
possesses the power of causing them to combine-to-form-anhydrous.
sulphuric acid. For this purpose I prefer to use spongy platinum, either
alone or distributed over some porous substance, such as pumicestone,
placed in a tube or some suitable apparatus heated to a low red heat.
The vapour of anhydrous sulphuric acid thus obtained I cither condense
by itself in a suitable apparatus, or cause it to be absorbed by concen-
trated sulphuric acid, and thus produce the so-called Nordhausen oil of
vitriol.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Stevens Squire in the Great Seal Patent
Office on the 18th March 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
STEVENS SQUIRE, Manufacturing Chemist, of 37, Acacia Road, St. John's
Wood, in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of September, in the
year of our Lord One thousand eight hundred and seventy-five, in
the 39th year of Her reign, did, for Herself, Her heirs and suc-
cessors,-give-and-grant_unto me, the said William Stevens Squire,
Her special license that I, the said William Stevens Squire, my
executors, administrators, and assigns, or such others as I, the
said William Stevens Squire, executors, administrators, or 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 King.
dom of Great Britain and Ireland, the Channel Islands, and Isle of
Man, an Invention for " IMPROVEMENTS IN THE MANUFACTURE OF NORDHAUSEN
OIL OF VITRIOL," upon the condition (amongst others) that I, the said
William Stevens Squire, my executors or administrators, by an instru-
ment in writing under my hand and seal, should particularly describe

page_text: 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 imme-
diately after the date of the said Letters Patent.
I NOW KNOW YE, that I, the said William Stevens Squire, do
hereby declare the nature of my said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, that is to say :-
I take ordinary sulphuric acid as concentrated as possible, and cause
the vapour of it to pass over a highly heated surface, and for this
purpose I prefer to use a platinum tube heated to a bright red heat, or
preferably even to a white heat. This tube may be either empty or
partially filled with platinum foil or some porous substance, such as
pumicestone. Tubes of other metals capable of supporting the requisite
heat may be employed, or earthenware tubes or constructions of brick-
work, but I find platinum tubes to be practically most efficient on
account of their resistance to heat and their requiring far less fuel to
produce the requisite effect. In this way the vapour of the sulphuric
acid is either entirely or in part decomposed into water, sulphurous acid,
and oxygen in equivalent proportions. The gases thus produced are
then cooled, preferably by means of a lead worm immersed in water,
which condenses the greater part of the water produced in the decom-
position of the sulphuric acid. The gases are then passed over or
through sulphuric acid or some other substance capable of drying them
thoroughly. For this purpose I prefer to use a tower filled with pieces
of coke saturated with sulphuric acid somewhat similar to the so-called
Gay Lussac towers used in sulphuric acid factories. The dry mixture
of sulphurous acid and oxygen thus obtained I noxt submit to the
action of some substance capable of causing them to combine to form
anhydrous sulphuric acid. For this purpose I prefer to use platinum
black, or spongy platinum, either alone or distributed over the surface of
some neutral substance, such as pumicestone or asbestos, so as to obtain
great extension of surface, but certain metallic oxides and compounds
may be also employed, such as oxides and sub-sulphates of iron,
chromium, and copper, or a mixture of any of them, either alone or
mixed with some neutral substance, such as pumicestone or asbestos,
although their action is not as a rule so powerful as that of platinum
black, or spongy platinum. These substances, whichever of them may

page_text: be employed, I arrange in a tube or chamber constructed preferably of
platinum or of earthenware called the recomposer, moderately heated to
the temperature of a dull red heat, or to such lower temperature as may
be found to give the desired result. Under these circumstances the
_sulphurous acid and oxygen combine to form anhydrous sulphuric acid,
the chemical formula of which is 8 O,. This body-I-either-condense-by-
itself in a suitable apparatus or cause it to be absorbed by concentrated
sulphuric acid, and thus produce the so-called Nordhausen or fuming
oil of vitroil.
Any portion of the mixture of sulphurous acid and oxygen which
has escaped the action of the combining or katalytic substance, and
passes away from the condensing apparatus, I cause to pass through
another recomposer, and thus obtain the whole or nearly the whole of
the gases in the form of anhydrous sulphuric acid.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider
to be novel and original, and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is, the pro-
duction of anhydrous sulphuric acid by firstly effecting the decomposition
of sulphuric acid by the employment of a high temperature, substantially
as herein-before described, and then subsequently desiccating the gases
evolved, and then submitting such desiccated gases to the action of
spongy platina or other substance or substances capable of effecting the
re-combination of the desiccated gases as herein-before described.
In witness whereof; I, the said William Stevens Squire, have to
this my Specification set my hand and seal, the Tenth day of