CERTAIN IMPROVEMENTS IN THE TREATMENT OF METALLIC OXIDES AND THEIR COMPOUNDS, AND IN APPARATUS FOR THE SAME
Year: 1846

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ADRIEN
CHENOT, of Clichy la Garenne, near Paris, in the Kingdom of France,
formerly a Student in the Royal School of Mines in France, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the Thirty-first day of December, in the tenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Adrien Chénot, Her especial licence, full power, sole privilege and
authority, that I, the said Adrien Chénot, my executors, administrators, and
assigns, and such others as I, the said Adrien Chénot, my executors, adminis-
trators, 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 mentioned, should
and lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS
IN THE TREATMENT OF METALLIC OXIDES AND THEIR COMPOUNDS, AND IN APPARATUS
FOR THE SAME;" in which said Letters Patent is contained a proviso, obliging me,
the said Adrien Chénot, by an instrument in writing under my hand and seal,
particularly to describe and acertain the nature of my said Invention, and in
what manner the same is to be performed, and to cause the same to be inrolled
in Her 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.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Adrien Chénot, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, is particularly described
and ascertained in and by the following description thereof, reference being
had to the Drawings hereunto annexed, and to the letters and figures marked
thereon (that is to say):-
My Invention of "Certain Improvements in the Treatment of Metallic
Oxides and their Compounds, and in Apparatus for the same," relates,-
First, to the manufacture of iron, steel, and cast iron, and in treating or
operating upon the latter for certain purposes, also the manufacture of zinc
and copper, as well as to the preparation or production of spongy or porous
masses of metal applicable to various useful purposes; and, lastly, to the
application of the apparatus hereafter described to the processes or manu--
factures above mentioned, as well as to the other purposes which will be here-
after set forth, and particularly the distillation of mineral substances, baking or
burning earth or pottery ware, the cementation or preparation of iron for steel,
the re-melting of cast iron and glass in different mixtures, in order to decom-
pose them.
I will now proceed to point out in succession, first, the theory; second, the
means I employ, and the application of my Invention or improvements. The
theory will vary according to the physical quality or characteristics of the metals
.or matters to be treated, that is, whether they are or are not volatile, and also
whether they are more or less fusible than their gangues. This will constitute
four classes, viz:-First, fixed or non-volatile metals less fusible than
their gangues; second, intermediate metals; third, metals more fusible
than their gangues; fourth, volatile metals. Now, the oxides of iron, lead,
zinc, and tin are reducible by carbon, by hydrogen, and also by carbu̟-
retted gases. It is also known as a theoretical truth, that carbon and the
carburetted gases carbonize after reducing the mass, and that hydrogen reduces
without carbonizing the mass also; it therefore follows that if the operation of
reducing with carbon is prolonged, the following results will necessarily take
place, viz: After the soft iron has been obtained, hard iron, steel, and cast
iron will be produced, but these successive changes can never take place if
hydrogen only is used. On the other hand pure or carburetted hydrogen
possess the power which carbon does not of facilitating volatilization. These
points being understood, I will now proceed to explain in order the different
classes.
First class. Fixed or non-volatile metals less fusible than their gangues.
The manufacture of iron.--In taking iron for an example of this class, my

page_text: theory is that if the oxide of iron be brought in contact with coal or carbon in a
close vessel, it will be reduced at a red heat in a shorter or longer time, accor
ding to the degree of heat employed. The reduced oxides constitutes a spongy
metallic mass containing the gangues. If this spongy mass is highly heated
the gangues will separate and melt out, the infusible iron remaining isolated.
This is the abstract theory, but it is necessary to add to it a theory derive.l
from observation and experience, which is, that the gangues will always meet
with some oxide of iron in an ore only partially reduced, and consequently
they form a very fusible ferruginous compound, which may be easily brought
into a liquid state, either by the addition of oxide or by incomplete reduction.
This theory differs from the opinions of chemists, who have generally con-
sidered the gangues as a great obsticle, admitting, however, at the same time
that the direct treatment of the ore by a preliminary reduction is correct and
true, and founded upon reason; but they were not aware of any other means of
melting the gangues except by other gangues, whereas my improved plan or
principle is to melt them principally by means of the oxide of the metal to be
operated upon.
The Manufacture of Steel.-It is easy to obtain iron from its ores;
but in order to make steel it is necessary after the reducing process to con-
tinue the operation until cementation takes place, and the sponge mass will
be composed of slightly fusible steel and a gangue, the liquation or melting
of which is a more delicate operation, for two reasons, first, because steel is"
fusible, and also because the oxide of iron will destroy the steel that is
formed; it is therefore necessary to avoid adding the oxide, and it is also ad-
visable to make choice of very pure ores, so as to obtain a perfectly metallic
spongy mass for the manufacture of steel; it will therefore always be pre-
ferable to employ the richest kind of ore, so that hydrogen only can be
employed to reduce them.
The Manufacture of Cast Steel.-After steel obtained without fusing the
ore or the spongy mass comes a different quality of steel, produced by melting
the highly carbonized spongy mass; this constitutes cast steel obtained direct,
and belongs to the next class. It is mentioned here as being the transition
state, and merely to observe that as this steel requires fusing, the gangues
liquate or melt out, and that consequently they do not absolutely prevent the
employment of ore of moderate richness; and they may be fused or melted
by the addition of earths and alkalies, and even a small quantity of oxide may
be employed to vary the hardness of the steel, which will cause it to approxi-
mate to cast iron.

page_text: Second class. Metals equally fusible with their gangues.
Manufacture of cast iron.-By carrying on the reducing process beyond
producing the spongy mass of cast steel, cast iron is obtained. During fusion
cast iron separates from its gangue, in consequence of its difference in
density, it may therefore be obtained by continuing the reducing cementation
and fusing processes; but as far as the gangues are concerned complete
fusion does not take place, as an unmelted refuse or slag will float upon the
surface. Nearly the same observations may be made of copper. This is the
theory for cast iron, and it is characterized by the fact that the gangues do
not require to be entirely melted.
Third class. Lead, antimony, tin, and metals more fusible than their
gangues. In this case the temperature required for the reduction of the oxide
being higher than that at which the metal melts, the result will be that the
metal will fuse and liquefy in proportion to and as the reduction proceeds.
This is the case with lead, antimony, tin, and substances very rich with zinc ;
and as the gangues are inert and not injurious they need not be melted, but
may be allowed to remain separate or in a state of sponge. This is the theory
for these substances, and I may add that the gases are particularly applicable
to this class.
Fourth class. Zinc, arsenic, mercury, and other volatile metals.-Antimony
has not been classed among the volatile metals, because in the metallic state
it is the least volatile, while, on the contrary, it is in this state that the above-
mentioned metals are the most so; therefore, as regards the reducing state,
antimony is the least volatile. For an example of this class I will take zinc.
The practical difficulties that are incidental to the reducing and condensing
processes, and also those arising from any irregularities in the operations as
well as supplying the pots, and also the non-conductibility of a mixture of coal
and pulverized substances, are well known. Now the oxide of zinc is perfectly
reducible by hydrogen and the carbonized gases, and may be conducted by
these gases wherever it may be required to be condensed and run into moulds.
By reducing it by means of hydrogen, pulverization and mixture with coal
would be dispensed with. There are no pots to fill and empty, and the
operation is rendered continuous and speedy, and the result very economical.
The gangue remains inert in the state of a spongy mass, and as the sulphurets
of lead or the carbonates of this metal which adulterate the orcs of zinc
are, on the one hand, but slightly volatile at the temperature at which the
zinc is vaporized and carried over by the gases, it follows that the zinc
obtained in this manner is infinitely purer than when obtained in the ordinary

page_text: entirely new, and is applicable to mercury, arsenic, and other volatile metals.
I would merely observe that by introducing a current of air an oxide of
arsenic may be at once formed and condensed wherever it may be found
desirable, and by introducing a stream or current of sulphurous vapor sulphurets
will be produced. Mercury may be treated in the same manner, and if it
will be required to obtain it in any other than the metallic state, it will only
be necessary to employ vapours or gases of different kinds, as may be required.
THEORETICAL SUMMARY.
First class. It is in the liquid state that metals combine most readily
with sulphur, phosphorus, arsenic, silica, alumina, and such matters. When
the mass liquefies it is not so much the metals that become liquid or melt as
the gangues, and these latter attract from the metal a great proportion of
the foreign matters, the result of which is that the metal will not be altered
by the operation by the fuel or by the gases; in fact, that all these are matters
of but slight importance to the metal, and that the only agent which acts upon
it is heat, and that, consequently, the metal will be of good quality if the ore
is good, whatever fuel may be employed.
Second and third classes.-As regards cast steel and cast iron obtained
from the ore by the processes of reduction or super-cementation, the quality
of the metal depends upon the gangues alone, the nature of the fuel being
unimportant, as it acts only as a calorific agent.
Fourth class. In relation to zinc, tin, lead, antimony, mercury, and arsenic,
it has been clearly shewn that under the influence of a pure gas they will be.
as pure as they can possibly be made, for the gas forms fixed or determinate
compounds with sulphur, phosphorus, and such like substances. Metals of
the first class treated wholly or partially with a pure gas ought then to be
considered as having been obtained of the greatest possible purity; I consider,
therefore, that purifying metals by remelting them under the influence of
hydrogen, for the purpose of improving their quality, is a novel application.
By the employment of the gases I am enabled to produce metallic salts at
temperatures at which they are not decomposable, or under the influence of
which they are formed or exist, such, for instance, as the chlorurizing, the
sulphurizing, the nitrifation of metals unencumbered or not arranged by the
interruptions in the process or the operation of injurious matters.
Means of application.-The means employed have for their principal object
rendering the process continuous, and gradual heating and cooling, for the
purpose of utilizing all the heat. One kind of apparatus consists of a cru-.

page_text: sible containing a mixture of ore and fuel, and placed in a furnace, but it is
necessary to heat it with care, and when the ore is reduced to withdraw and
allow it gradually to cool; the crucible must then be emptied and the opera-
tion recommenced. It will be easily understood that this mode of operation
cannot be usefully employed. My means of application are based upon the
experience obtained by trying a variety of plans, and those which answer the
purpose and effect my object in the best manner may be divided into four
classes, as follows:-First, stationary apparatus, the operation of which is not
continuous; second, stationary apparatus, the operation of which is uninter-
rupted; third, moveable apparatus; fourth, apparatus in which the vessels
or crucibles are moveable. The first class consist either of a pottery or porce-
lain furnace filled with crucibles previously charged with layers of fuel and
orc, or an ordinary cementation furnace with vessels. made of carth, bricks,
or cast iron, and previously charged with layers of fuel and ore reduced to a
coarse powder. These two plans may be rendered in some degree continuous
by arranging them in sets of threes and heating thom by a moveable furnace,
which may successively be brought before cach. This furnace may be em
ployed for welding during the reducing process, and the waste heat may be
employed for reducing. The operation will be as follows:-While one furnace
is being heated the second is cooling, and the third is being charged; the
reverberating furnace or forge fire, which is intended to heat the ore is
withdrawn from before the furnace that has been heated, when the process of
reduction is complete, and is placed before that which has just been charged.
The operation or process of reduction by this means is upon the whole
apparatus made continuous, but as regards each separate furnace, which must
be first heated, then cooled, and then heated again, the operation will of
course be an interrupted one, and a considerable consumption of fuel will be
the result. This system, moreover, is only applicable to the first class of ores,
and when carbon is employed as the reducing matter. In order to facilitate the
charging, emptying, and cooling of the apparatus, it is as well to furnish
the chambers with lids or moveable covers, whereby any necessary operations
or repairs are rendered more casy. It will be unnecessary to give any
drawings of the above described apparatus, as the explanation above given
will be already understood without them.
Second class. One or more vessels, cylinders, or retorts are placed ver-
tically in a furnace, and the upper and lower ends thereof are made respec-
tively to pass through the upper part or roof and lower part or sole of the
furnace, so that the said vessels, cylinders, or retorts may be charged at the
upper end and emptied from below, and heated by the waste heat of the

page_text: welding fire.
This constitutes a second system, and being continuous is
applicable for the employment of carbon or gases, and for operating upon all
classes of minerals. This construction of apparatus is shewn in Figs. 1, 2, 3,
and 4 of the accompanying Drawings, in which Fig. 1 represents an elevation
of the apparatus. It will be seen that the upper ends of the cylinders or
retorts project above the roof for the convenience of charging them, and the
lower ends thereof descend below the level of the fire-grate, so that their
contents may be discharged with facility. This latter operation is effected by
means of a cylindrical discharging barrel or cock, shewn detached upon an
enlarged scale at Fig. 5. The internal barrel of this cock is furnished with
one opening only, while the case or external drum which encloses it is
furnished with two openings, so so that the internal drum or barrel of the cock
may be brought into communication with the cylinder or retort, and filled by
bringing its aperture into coincidence with the upper opening of the external
drum, and by turning the internal barrel half-way round, the communication
with the cylinder or retort is closed, and the barrel will be emptied of it's
contents by its opening coming opposite to the lower aperture of the external
drum. This arrangement answers the purpose exceedingly well, but it requires
power and care in working it; and in order to make the charge descend
regularly it will be necessary to turn the cock or barrel alternately in opposite
directions. Instead of the plan just described a slide valve may be employed,
or a piston may be used, which may be raised and lowered by means of a lever
or a rack and pinion. By lowering the piston the charge descends, then by
raising the piston the whole of the ore will be lifted up.
Fig. 1, it will be seen that on the left-hand side of the
moveable reverberatory furnace mounted on wheels, and on the right-hand
side there is a forge fire with a moveable roof, either of which plans may be
employed to collect the flames which serve to heat the reducing cylinders.
Fig. 2 is a horizontal section of the apparatus, taken just about the level of
the fire-grates. The fire-grate of the large furnace is represented, in case the
reverberatory furnace should not be employed; if, however, the latter is made
use of, the former is closed. Fig. 3 represents a section in the line C, D, of
Fig. 2.
0, 0, 0, 0, are seven apertures made through each side of the central
space where the supplementary or additional fire-grate is placed; these open-
ings are made for the purpose of distributing the flame and heat around the
cylinders or retorts. Fig. 4 is a section in the line A, B, of Fig. 2. It will be
seen that the furnace is divided into two parts by an upright partition of
masonry m, m, m, m, which may also assist in supporting the roof if required,
but this partition acts principally as a regulator of the heat which accumulates
Upon referring to
furnace there is a

page_text: and is stored up in its body; but if gas is produced, retorts may be placed in
the space V, V, which is cut out of the mass.
If retorts are heated in this
space V, V, the flames and heat may be brought back from the upper part of
the furnace and made to pass through flues communicating with this space at
the point of contact with the exterior of the roof of the additional fire-grate.
Third class. A stationary furnace suitable for welding or melting is elongated
by the addition of a series of moveable receptacles, chambers, or ovens mounted
on wheels like waggons, and furnished at each end with apertures, whereby a
communication with the furnace may be opened at one end, and a communi-
cation with a second chaniber at the other. These receptacles, chambers, or
ovens contain crucibles or small vessels made either of earth or cast iron, and
are heated and cooled gradually. When one oven or chamber with its con-
tents has been heated sufficiently, and it is considered that the reduction of its
contents is complete or finished, it is moved out of the way of the welding
furnace, the flame or heat from which has been employed for heating it,
and its two openings, one at each end, are closed, and a second oven or
chamber is brought up to the furnace and made to occupy the place from
which the former one was removed, and all the other ovens being brought up
in succession the operation is made continuous. For volatile minerals the
chamber contains horizontal or vertical cylinders, arranged in such a manner
as to cause the reducing gas-to enter at one end of the cylinders and the
products to be collected and carried off by the other, taking care in operation
to employ the gas in proper quantities according as the chambers arrive at the
most convenient temperature for reducing or distilling each mineral.
Fig. 1, Sheet II., is a longitudinal section (taken in the line A, B, of Fig. 2)
of the whole apparatus, with the moveable receptacles or chambers. The flame of
the reverberatory furnace R, after having been employed for cementing the ore
on the floor S, passes successively through the five or more chambers or ovens
C, and gradually heats the cylinders, retorts, or crucibles which have been
placed therein, and then passes off through the chimney G. These ovens or
chambers are placed on wheels, and move along a railway. Upon referring to
the plan view, Fig. 2, it will be seen that there are two lines of rails, having at
each end thereof a turntable T, by means of which the moveable ovens or cham-
bers may be moved along, or transferred from one line to the other, as may be
required. The ovens are charged on the side line of rail, and then transferred
by means of the turntable at the end to the other line behind the chimney,
under which they are made to pass in succession as the operation of heating
at the other end proceeds. The chimney is furnished with a moveable frame
or box Z, forming a sliding shutter, which may be raised or lowered to allow

page_text: the oven C to be pushed through. When the contents of the first oven that
is in direct communication with the furnaces has been brought to a proper
state, the oven is removed to the other line to be discharged of its contents,
and the other ovens are pushed forward. It will be evident to any person
conversant with the subject, that the same effect may be produced in a different
manner. I do not therefore intend to confine myself to the arrangement shown
in the Drawing. For instance, the same object may be effected by arranging
the ovens on a circular track, and jointing them to each other, the furnace
being on one side of the track and the chimney at another point.
Fourth class. A stationary welding or melting furnace.is elongated or
prolonged by the addition of a stationary oven, the sole or floor of which is
formed of several sets of cylinders or rollers, which are connected to each other
by gearing, and may be actuated in sets. Each set of rollers or cylinders is
made to support and carry earthen slabs or plates of metal about the same
length as that occupied by the set of rollers, and upon these plates or slabs are
placed the pots, crucibles, or vessels containing the matters to be operated
upon, and which vessels are made gradually and successively to advance
from the lowest to the highest temperature required, and vice versâ, exactly
as in an oven for annealing glass.
The Figure in Sheet III. of the accompanying Drawings represents a longi-
tudinal vertical section of an apparatus constructed on the principle above re-
ferred to; F, F, are two reverberatory furnaces, one being used for melting and
the other for reheating, welding, or other purposes. The flame and heat from
these furnaces enters at C, and passes into the series of reverberatory furnaces
or ovens 1, 2, 3, 4, 5, and after passing through them and entering all the inter-
stices between the pots or vessels o, o, o, which are placed therein, finally escapes
through the chimney; r,, r, r, are registers placed between each set of cylinders
or rollers C, C, and suspended from chains which pass round and are attached
to pullies m, m, on the long shaft n, which is provided at one end with a winch,
in order to actuate the same when required. The operation of the apparatus
is as follows:-The pots or vessels o, o, o, are filled or charged at the right-
hand end of the apparatus near the chimney, and the proper number of pots
being placed on the slab or plate P¹, the register is raised up and the plate P
with its pots is pushed into the furnace on the rollers C. A series of plates is
thus filled with pots until the furnace is quite full, and when the first lot (that
is, those that are in the compartment 1) have been sufficiently heated, the
register in front is raised, and the plate with the pots thereon is pushed out of
the furnace, and the second plate takes the place of the first. This movement

page_text: forward of the plates is effected by actuating the rollers by means of toothed
gear, but various other plans may be devised for effecting the same object.
SUMMARY OF THE VARIOUS MEANS OF APPLYING MY METHODS ACCORDING TO
PARTICULAR CIRCUMSTANCES, WHICH MAY PRESENT THEMSELVES IN PRACTICE,-
SOLUTION OF EACH OF THE QUESTIONS PROPOSED, EXPRESSING THE DESIGN,
INTENTION, AND THE CHARACTER OF THE PATENT APPLIED FOR, -REDUCTION
OT THE OXIDES OF IRON, OR OF ITS COMPOUNDS BROUGHT INTO THAT STATE.
If it be intended to reduce our oxide of iron, having regard to its ultimate
employment, the reduction is effected in a special furnace, without smelting,
and the substance thus reduced may be employed for the following purposes,
which form a part of this Invention, that is to say, the novel application:-
First, it is well known that in the manufacture of lead, antimony, copper;
&c., &c., a pretty considerable quantity of old iron is used for the purpose of
desulphurizing the ores; iron ores reduced at the time may be advantageously
substituted for the same. In ordinary refining of cast iron, the reduced ore
may be substituted with advantage for the old iron usually employed, as it
will expedite the refining operation and improve the quality of the product.
The ore thus reduced may be obtained very cheap, and may be employed
in various branches of manufactures, as a desulphuretting, dephosphoretting,
and dechloridizing agent, as well as to decompose the alkaline or metallic
sulphurets, phosphates, and chlorides.
Second, the reduced ore or metallic sponge may be treated with acids to
obtain various salts of iron, and employed as a substitute for the old iron
usually made use of to obtain sulphates, acetates, phosphates, and chlorides, or
other salts of iron; and also in the manufacture of hydrogen gas.
Third, the metallic dust produced by pulverizing; the sponge may be very
economically employed for making galvanic batteries, which would be of im-
mense power, owing to the great extent of surface exposed to chemical action.
Fourth, it is well known that iron filings have been hitherto used for
hydraulic works, terraces, roofing, joints, &c. The high price of this substance
has restricted its use and prevented its general adoption. The metallic
powder may be advantageously substituted for iron filings; the low price at
which it may be produced, and the unlimited quantity which may be manu-
factured, renders the reduced ore a most valuable substance for public and
private works, particularly as a substitute for or in addition to bitumens;
hydraulic lime or cement, &c. This reduced ore may be mixed in various pro-
portions with silica, in order to form silicates without the application of heat

page_text: with lime, silica, alumina, and sulphur, and to form hard bodies for various
purposes; also in various proportions with earth and powder of reduced metals
to make marbles and stuccoes, which may be colored by oxidation.
Lastly, in order to make an alloy or mixture of various kinds of iron or
steel, or of these two metals with others, it is sufficient to mix the powders and
weld them together. Inlaid work may. thus be produced of as many metals as
may be desired, and the metals may be mixed in such a manner as to produce
a striped design, either straight or curved, or of any other character.
Fifth, the furnaces which I employ for the second, third, and fourth classes
may also be economically employed for burning lime, baking earthenware
and porcelain, for distilling and for the carbonization of vegetable or mineral
substances; they render these operations continuous, and they are also suitable
for manufacturing steel by cementation, and for all melting or baking opera-
tions, as by the continuity of their action considerable economy is effected.
These novel applications constitute a part of my Invention intended to be pro-
tected under this Patent, as in none of the branches of industry above men-
tioned have these means of utilizing heat been employed, neither has the
means of regulating at will the degree of heat required, nor the utilization of
the products obtained by the reduction of metallic substances.
METHOD OF REDUCING AND TREATING VARIOUS SUBSTANCES.
Manufacture of iron.-As a consequence of my methods, I suppose
every substance converted into an oxide, the result either of prolonged
operation in the furnace or of slow oxidation. I attach great importance
to this oxidation, and will now give an example, which will serve to
explain all other cases:-I will take, for example, the treatment of cast
iron by my method, supposing ore of the richest kind to be employed,
an ore which by the ordinary method is refined by remelting. One of the
principles of this Invention is not to melt the ore, the cast metal is there-
fore not smelted by my method, but treated in the same manner as an
ordinary ore. For this purpose, whether the substance be presented to
me in the form of iron filings or cuttings, or whether I pulverize it
whilst hot near the furnace to granulate it, I make up these substances
in a divided state into bricks, which I oxidate by continued exposure to the
air and sprinkling with water; or after leaving them for some time to harden
I oxidate them in a furnace by means of steam or nitrous vapour. In order
'to solidify the pulverulent matters they are made into bricks composed of
about four-fifths of raw matters and one-fifth of matters reduced or in the
metallic state. Take, for instance, a case in which iron scales may be em-

page_text: ployed. A rich ore is thus reproduced, which may be treated in the manner
hereafter described, observing that by this treatment the sulphur, phosphorus,
silicium, and aluminium, &c., are acidified, and may disappear in the reduc-
tion, particularly that by gases, as the temperature is not sufficiently high to
revivify the silicium and aluminium, whilst the phosphorus and sulphur form
permanent compounds with the reducing gases, or more particularly with their
hydrogen. These bricks being put into an oven or furnace, and either ope-
rated upon by means of layers of coal, or by a reducing gas, the result is a
metallic sponge of the greatest richness. It is iron, which only requires to be
submitted to a sufficiently high temperature to agglomerate its particles, when
the oxides, silicates, and ferruginous earthy matter may be driven out by
forging. The metal is here treated as an elementary substance, which fully
explains the superior quality, and also the difference of the improved process
compared with the old one, as it will be seen that the metal is first converted
into the state of ore in order to treat it.
These flames are
above described,
I will now enquire, with respect to an ore of moderate richness, into the
question of liquation of the gangues. As has been above explained, all my
apparatus are composed of two distinct parts. In the one which I call the
the liquefying or smelting furnace the temperature is raised as high as possible,
either on the sole of the furnace or through the fuel. The excess of tempera-
ture shews itself by the flames escaping from the flues.
employed to reduce the ores in suitable apparatus, such as
and which constitute the reducing ovens or furnaces. From these the ore is
taken in the state of metallic sponge, containing the gangues, and constitutes
a body of which one of the elements, the iron, is infusible, whilst the gangues
in the presence of a small quantity of oxide of iron are all very fusible. The
result of this is, that by placing the substance on the sole of a liquefying or
smelting furnace, or in the fire, and heating it, and working it the same as old
iron, the result will be merely, from the simple fact of the nature of the
operation of smelting at a high temperature that the gangues will be elimi-
nated. The mass of metal is in some degree purified by the addition of
certain portions of oxide during the operation. By operating in this manner
the ore is never melted, and consequently does not combine with any other
substances. The quality of the product may therefore be calculated from
that of the ore, without being influenced by the quality of the fuel, which only
requires to give out a good heat. The flame and gases lost in ordinary fur-
naces may be employed when they are abundant for reducing and smelting, or
merely for reducing, either wholly or partially.
Manufacture of steel.-It will be conceived from what has been said that

page_text: to obtain steel it is sufficient to prolong the reduction, and to cement the
sponge, which is afterwards welded in the same way as iron.
Manufacture of cast steel.-By pushing the cementation still further a very
hard sponge is obtained, the particles of which are closely agglomerated. By
melting this in the same manner as cemented steel, cast steel will be produced
with the scum or scoria floating at the op, whence it may be run off.
Manufacture of cast iron.-By pushing the cementation to the highest
point blistered steel will first be obtained, and afterwards a sponge of cast iron
containing its gangues. These latter may be separated by melting this sponge
on the bed of a reverberatory furnace, or in a cupola furnace, or even in
a blast furnace. The welding furnaces will then become melting furnaces.
It will be scen from this final result that of all ferruginous substances cast iron
is the most expensive by my processes, and that the refining of it is only
advantageous from the richness of the ore, which is called cast metal, and that
otherwise a rich ore is for my purposes of greater value than this latter.
METALS OF THE SECOND CLASS.
Transition. I here choose copper as an example of transition above all other
metals, either fixed or volatile, because the temperature of reduction of copper
is less than that of the fusion of the gangues, and that this latter is more fusible
than the gangues. Having reduced a copper ore converted into an oxide, it
is treated in the manner already described for cast iron; the gangue is melted
or floats on the top. For antimony, as its regulus is more fusible than the
gangues, and runs off at the time of its reduction, the operation is confined to
reduction, the object of which is to detach the regulus. On being run off, the
Volatile metals.-These are zinc, arsenic, mercury, &c. To obtain these
metals the method is divided into reduction and condensation. I refer to
what I have already said in a general sense of these metals, and will
enter into some details for zinc. By the means now employed the ore is
pulverized and mixed with powdered coal. In this state it is introduced into
earthen vessels at a white heat. These latter being cooled by this contract,
are a long time before they regain their heat, and are thus rendered liable to
break. On the other hand, the mixture of pulverized substances, in which
half the quantity of coal is interposed, constitutes a very imperfect conductor,
so that the outside of the vessel is at a white heat while the interior remains
comparatively cool. The oxide of zinc is thus reduced, but gradually; and to

page_text: produce the condensation it must pass through and come in contact with a
very large quantity of foreign matter, which retains or holds back the metal,
the result of which is a great loss of this latter, and a very slow and tedious
operation, as the subliming vessel must be emptied of the matter scarcely
exhausted of zinc, and this latter, on coming into contact with the air, escapes
in the form of vapour, which occasions loss and danger. I introduce the
ziuc ore in the upper part of a cylinder, hydrogen being admitted at the lower
part. When the ore is exhausted a certain quantity is made to escape at
bottom, which is replaced at the top. The gas carries off the reduced zinc,
and the metal follows the gas as long as the temperature is sufficiently high,
and ceases to do so as soon as it is lowered, the result of which is that the
condensation of any series of cylinders may be effected in the same space. The
operation is therefore perfectly continuous; the matters operated upon are
good conductors, and easily heated, although gradually, consequently the
operation is accompanied by great economy of fuel, a larger product, great
rapidity with small apparatus, and the metal obtained is of better quality.
This results from the action of the gas.
In witness whereof, I, the said Adrien Chénot, have hereunto set my
hand and seal, this Nineteenth day of June, in the year of our Lord
One thousand eight hundred and forty-seven.
ADRIEN (L.S.) CHÉNOT.
Taken and acknowledged by Adrien Chénot
(party hereto), at Paris, in the Kingdom
of France, the Nineteenth day of June,
One thousand eight hundred and forty-
seven before me.
seven. before me.
THOMAS PICKFORD,
Her Britannic Majesty's Consul at Paris.
AND BE IT REMEMBERED, that the instrument aforesaid was stamped
according to the tenor of the Statute made in the fifty-fifth year of the reign 3
of His late Majesty King George the Third.