IMPROVEMENTS IN THE DISOXYGENATION OF CERTAIN BODIES, AND THE APPLICATION OF THE PRODUCTS. THEREFROM, EITHER SEPARATELY OR SIMULTANEOUSLY, TO VARIOUS USEFUL PURPOSES
Year: 1850

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, GUILLAUME
FERDINAND DE DOUHET, of Clermont Ferrand, in the Republic of France,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of
Great Britain and Ireland, bearing date at Westminster, the First day
of June, One thousand eight hundred and fifty, in the thirteenth year of
Her reign, did give and grant unto me, the said Guillaume Ferdinand
De Douhet, exors, adiñors, and assigns, Her especial licence, full power.
sole privilege and authority, that I, the said Guillaume Ferdinand De
Doulet, my exors, adñors, and assigns, or such others as I, the said
Guillaume Ferdinand De Douhet, my exors, adññiors, or assigns, should at
any time agree with, and no others, from time to time and at all times
hereafter 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, and, the Islands of Guernsey, Jersey, Alderney,
Sark, and Man, and in all Your Majesty's Colonies and Plantations
abroad, my Invention of "IMPROVEMENTS IN THE DISOXYGENATION OF CERTAIN
BODIES, AND THE APPLICATION OF THE PRODUCTS. THEREFROM, EITHER SEPARATELY
OR SIMULTANEOUSLY, TO VARIOUS USEFUL PURPOSES;" in which said Letters
Patent there is contained a proviso requiring that I, the said Guillaume
Ferdinand De Douhet, should particularly describe and ascertain the nature of
my said Invention, and in what manner, the same is to be performed, by
an instrument in writing under my hand and seal, and cause the same to
be enrolled in Her said Majesty's High Court of Chancery within six

page_text: calendar months next and immediately after the date of the said in part
recited Letters Patent, as, reference being thereunto had, will more fully and
at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Guillaume Ferdinand De Douhet, do hereby declare the nature of my
Invention, and the manner in which the same is to be performed, are particu-
larly described and ascertained in and by the following statement thereof,
that is to say:-
The deoxidation or disoxidation, otherwise the loss of oxygen, which is
undergone by certain bodies, imparts to them new properties useful to the
arts and industry. It is this deoxidation, and the applications resulting
therefrom, that form the object of this Patent. The Specification must there-
fore notice and describe, first, the processes for deoxidizing; secondly, the
different applications which result from these processes, whether they are made
by employing one by one (singly) or united together (simultaneously). The
bodies which it is here intended to deoxidize are all sulphates soluble in
water, metallic, or alcaline, and certain insoluble sulphates, such as those
barytes of strontian and of lime. The deoxidation of the first is made by the
I deoxidize
humid method, and that of the second by the dry method.
sulphates by the humid method by placing these sulphates dissolved in water
in contact with sulphurets, also dissolved in water, and which in this state have.
a strong tendency to become again sulphates by receiving oxygen from the
bodies which are being deoxidized..
In order that the operation may give products free from impurity, one of
the two substances which combine must form an insoluble precipitate from
the moment the mixture is made, so that the other remains transformed and
dissolved in the liquid. But sometimes it is more useful for obtaining certain
products to cause the formation of a double precipitate on the part of the two
substances, as I will hereafter explain. In the system of deoxidation, the
deoxidizing body is a soluble sulphuret, the body to, be deoxized or deoxydated
is any sulphate likewise soluble, and the precipitates are obtained. pure or
mixed according as one or both of the two bodies producing this double
decomposition has the property of being precipitated from the liquids which
kept them dissolved before they were placed in contact.
The watery or
aqueous solutions of the sulphurets of barium, strontium, and calcium, other-
wise called hydro-sulphurets of barytes, of strontian, and of lime, are powerful
agents for deoxidizing all soluble sulphates. I place in the first rank for this
object sulphuret of barium, and I show that when two solutions, one of sul-
phuret of barium and the other, of any sulphate (sulphate of soda for instance),

page_text: are mixed, the sulphuret of barium, receiving oxygen from the sulphate of
soda, becomes again sulphate of barytes, and is precipitated, while the deoxi-
dized sulphate of soda is transformed into hydro-sulphuret and remains
dissolved in the liquid. The deoxidation of the sulphate is complete if the
two terms of the double decomposition be mixed proportionably to their
respective equivalents, while it is partial if the sulphuretted solution is
employed in less quantity than the sulphate. The same principles-are applicable
to the sulphate of potash and of ammonia, but they are modified as to the
metallic sulphates of zinc, of copper, and of iron. Thus the sulphurets pro-
ceeding from the deoxidation of these different sulphates are themselves
insoluble in the water, and hence it is easy to conceive that they tend to
precipitate at the moment of their formation; but as it is the same with the
deoxidizing body, the sulphuret of barium, it happens then that the two terms
of the mixture are precipitated simultaneously; leaving the waters exhausted.
However, it would not be thus if, instead of sulphurets of barium, of stron-
tium, or of calcium, the sulphurets of sodium, potassium, or ammonium bo
employed as deoxidizing agents; for in regaining oxygen from the metallic
sulphates, these sulphurets are again converted into sulphates, but they would
nevertheless remain dissolved in the liquid, while the metallic bases united
with the sulphur would precipitate alone and pure from all alloy. The deoxi-
dation of the bodies thus specified by the humid process thus gives rise to
two orders of products. The first liquids, they are the alcaline sulphurets
which remain in the solutions; the second solids, they are the precipitates of
sulphate of barytės, strontian, or lime, and the hydrated metallic sulphurets,
which are formed alone or mixed according as the sulphate proceeding from
the deoxidizing bodies is soluble or insoluble. Now all are applicable to
different useful purposes in industry, whether they be used separately, simul-
taneously mixed together, as I will now explain. As to the deoxidation by the
dry process, it applies to insoluble sulphates of barytes, of strontian, and of
lime, which, brought back to the state of sulphurets, are valuable agents
(especially the sulphuret of barium, for the transformations I have just spoken
of.
The deoxidation of these various bodies by their calcination with
carbonaceous substances in crucibles and furnaces has been long known. I
will say nothing further in this process, but I must, however, make
the remark, that if it were intended to manufacture the sulphurets of
barium, strontium, or calcium in large quantities, it would be better to use
the following method:-I calcine in any furnace, but better in a reverberatory
furnace, blocks or cakes composed in volume of, for instance, of half sulphates
of barytes in powder, and the other half of coal or charcoal likewise in

page_text: powder, and a sufficient quantity of fine clay mixed with water, or, still 'better,
tar or asphalte, to bind and spread over the whole. These blocks or bricks,
dried till they have acquired sufficient firmness, are placed in the furnace, and
1 take care during their calcination, which ought to be intense and carried
on at a red heat during several hours, to direct upon them the greatest i
quantity of carbonated hydrogen gas that can be obtained from the com-
bustion of the coal in the furnace. For this purpose the part containing the
fire which throws the heat upon the sole on which the bricks are placed 'mušt
have a sufficient depth to allow a thick layer of coals to be kept constantly
ignited in it, so that a part of the hydrogen of the fiel may in this
manner be projected upon the incandescent bricks of sulphate of barytes.
The calcination ended, these bricks or cakes having become pulverizeable, are
washed in hot water; a portion of the sulphate of baryte deoxidized by the
coal and the hydrogen, and converted into sulphuret of barium, dissolves in
the water used for washing, forming hydro-sulphuret of barytes. This portion
varies from a fourth to three fourths of the weight of the raw sulphate
used, according as the operation has been more or less well conducted, and
whether a reverberatory furnace, which is the best, has been employed, or an
ordinary potery or limekiln, which, though very practicable, is less suitable.
The surplus remains insoluble in the water in the form of an earthy and
carbonaceous residue, and is an excellent manure. There is again another
method less generally used, but which in certain cases may be employed with
advantage, and which is carried out in the following manner: I place the
sulphate of barytes, broken into bits, in cylinders of cast iron, open at both
ends, communicating by one of the two ends with an apparatus evolving
hydrogen, and at the other end, by means of a curved tube, with a tub full of
These cylinders are placed in a furnace in such a manner as to bo
easily brought to a red heat, and during the operation it is necessary that the
stream of hydrogen from the apparatus in communication should constantly
play on the sulphate kept incandescent at the same degree of heat. If these
précautions be carefully observed sulphuret of barium is obtained after several
hours of calcination, and if the operation be sufficiently prolonged caustic
baryte fit for the humid purposes, for which it is obtained, for in this case
the hydrogen, after having deoxidized the sulphate, finishes by desulphurizing
it. This last mode of deoxidation and of preparation of barytes is, moreover,
applicable to many other sulphates and oxids, but in certain cases when the
sulphate of barytes is silicious, or when it is wished to accelerate its deoxida-
tion, it is well to add to and mix with the sulphate of barytes in the cylinders
a quantity of coal or of powdered charcoal in proportions varying according to
water.

page_text: .
circumstances. Here is now the specification of the products which the
.deoxidation of certain bodies by the humid way, and by the dry way give rise
to when they are made to react upon each other, some being in the state of
sulphates, the others in that of bydro-sulphates, and the applications they are
susceptible of in industry.
First, the sulphates of soda and of potash, deoxidized by contact with the
hydro-sulphuret of barytes, as has been explained, are fit for the washing and
whitening of wools or woven cloths, as well as the spun tissues of cotton; and
even of linen. These hydro-sulphurets are employed according to the means
used in washing, whether hot or cold, and sufficiently diluted to deaden their
caustic power. They are, moreover, fit for the purposes to which the hydrates
of soda and of potash are applied by soap makers, and form, when made into soap,
using oil and other ordinary materials, a good ordinary soap, having soda or potash
for its basis. They may, moreover, serve for the fabrication of artificial soda
or potash, for it is only requisite to extract the sulphur by exposing them very
concentrated and crystallized to the action of a stream of carbonic gas to obtain
soda or potash in the state of carbonate. But this manufacture can only be
advantageous if it is desirable to obtain a large quantity of artificial sulphate
of barytes, which, as has been before stated, forms the residue of this
dcoxydation.
Secondly, the hydrated metallic sulphurets or hydro-sulphurets of zinc,
copper, and iron, otherwise termed oxides of these different metals, mixed
with sulphur, which, as aforesaid, are precipitated when their different
sulphates are attacked by an alcaline hydro-sulphuret whose, sulphate is
soluble in water, such as soda and potash, form white, black, greenish, and
ochre-coloured precipitates..which, dried and calcined, become good colours to
use in oil and varnish painting. These same metallic precipitates, prepared
on the contrary by the deoxidation of their sulphates by means of an alcaline
hydro-sulphuret whose sulphate is insoluble, such as barytes, strontian, and
even linie, form, according to the principles above specified, double precipitates
of hydrated sulphurets of zinc, copper, and iron, and sulphate of barytes, of
strontian, or of lime, mixed together. These double precipitates which form
colours fit for oil or varnish printing, or for water colours, are susceptible of
important applications, and thus deserve a special mention with respect to
their fabrication and to their use. One mixes together two aqueous solutions,
the one of sulphate either of zinc, copper, or iron, the other of hydro-
sulphuret of barytes, both about equal in density; immediately the solutions
yield up their respective bases, which precipitate together in the form of an
abundant pap, composed of sulphate of barytes and of the metallic bases united

page_text: with sulphur in proportion to the equivalents of the two terms of this double
decomposition, The shade of colour of this double precipitate depends upon
the various metals that have been used. The essential point is, that the
double precipitation may take place, to the thorough exhaustion of the barytes
and of the metal, zinc, copper, or iron contained in the liquid, and this result
is arrived at either by trial or by mixing the two terms of the combination
proportionally to their equivalents. This double precipitate well washed,
decanted, and dried, is afterwards calcined at a red heat on the sole of a muffle
furnace or reverberating furnace, then thrown whilst incandescent into cold
water, by which it gains opacity, a valuable quality in painting. For water
colours the process is more simple; the double precipitate is made use of imme-
diately after its formation and subsequent washing, and to surfaces with water it
adheres without any other preparation; and when the painting is dry, it is sufli-
cient to pass over it a single coat of varnish, to preserve it from dampness
and to render it durable. These various precipitates, treated as has been
described, constitute: that with the zinc base a white colour fit to replace
ceruse; that with the copper or iron base other fast colours of various shades.
In lieu of hydro-sulphurets of barytes, strontian, or lime, prepared by the dry
process, and especially in place of the first, I sometimes use as a deoxidizing
agent, for metallic sulphates, a solution of poly-sulphuret of lime prepared
by the humid method by boiling together sulphur and lime in water. The
double precipitate which results from its mixture with the soluble metallic
sulphates is not complete, for the lime has not the same power to produce
precipitation as barytes and strontian, but the operation can be finished by
adding one of these hydro-sulphurets to the liquid, in order to precipitate what
had resisted the action of the lime. The colour obtained by this process,
though inferior to that described above, can be substituted for it in certain
cases. The hydrates of barytes and strontian prepared by known means
have also the same property of precipitating the bases of the soluble metallic
sulphates. To obtain by their use colours fit for painting it is sufficient
to mix a solution of hydrate of barytes, for instance, with a solution of a
metallic sulphate, either zinc, copper, or iron, after the above-described way of
manufacture; the double precipitates which result from it is fit for all uses
in painting, and for those already above described. The artificial sulphates of
barytes or of strontian, which precipitate separately, during the deoxidation
above specified, from the sulphates of soda or of potash, are susceptible of a
new application. It is known that the objection generally made to the white
oxid of zinc is the want of body and its bubbling the brush. To do away with
these defects the artificial sulphate of barytes is excellent when it is employed

page_text: in the following manner:-From 60 to 70 per cent. of its weight of white zinc
is incorporated with the sulphate of baryte when yet in the state of a paste;
the two substances being thoroughly mixed are then dried in small cakes,
afterwards calcinated and thrown at a red heat into cold water, as before
described. This is the only new application of this sulphate that I have
imagined or found.
First, the fabrication of the alcaline bydro-sulphurets by means of the
deoxidation of their various suphates by the humid and dry processes above
specified.
Secondly, the application of the hydro-sulphurets of soda, of potash, and of
ammonia to the cleansing and washing of woollens, cottons, and tissues, as
well as the application of the first two to the fabrication of soaps and of
artificial soda and potash.
Thirdly, the manufacture, according to the processes described above, of
new colours fit for oil, varnish, and spirits of turpentine painting, by means of
the deoxydation of the soluble metallic sulphates of zinc, copper, iron, and other
metals, and the precipitation of their bases either by alcaline hydro-sulphurets
whose sulphates are soluble, such as those of soda, potash, and ammonia,
if I wish to obtain colours with a single metallic base, or, on the contrary, if I
wish to have colours containing a double base, a half metallic and half alcaline
sulphate, by the alcaline hydro-sulphurets whose sulphates are insoluble, such
as those of barytes, of strontian, and of lime, and even by the hydrated
sulphurets and poly-sulphurets of lime prepared directly as well by the hydrates
of barytes and of strontium.
Fourthly, the application of a process in painting in water colours by the
colours above specified, with double metallic and alcaline base.
Fifthly, the employment of the artificial sulphates of barytes, of strontian, and
even of lime, formed during the deoxidation of the soluble alcaline sulphates
by the reaction of the hydro-sulphurets of barytes, of strontian, and of lime
in the white oxide of zinc, so as to improve it for being applied to painting.

page_text: I, Auguste Loradoux, of 10, Bedford Street, Strand, maketh oath and sayeth,
that the signature of Thomas Pickford, British Consul in Paris, and which is
attached to the Specification of Guillaume Ferdinand De Douhet's Patent for
Improvements in the Deoxygenation of certain Bodies, and the Application
of the Products therefrom, either separately or simultaneously, to various
Useful Purposes," is in the handwriting of the said Thomas Pickford.
T
AND BE IT REMEMBERED, that on the oath of Auguste Loradoux, the
Specification aforesaid was enrolled word for word as above written. And
also the Specification aforesaid was stamped according to the tenor of the
Statuté made for that purpose.