CERTAIN IMPROVE- MENTS IN MANUFACTURING STEEL AND CAST STEEL
Year: 1857

page_text: LETTERS PATENT to Charles Pauvert, of Chatellerault, Town in the
French Empire, Ecclesiastic, for the Invention of "CERTAIN IMPROVE-
MENTS IN MANUFACTURING STEEL AND CAST STEEL."
Sealed the 28th July 1857, and dated the 2nd March 1857.
PROVISIONAL SPECIFICATION left by the said Charles Pauvert at the
Office of the Commissioners of Patents, with his Petition, on the 2nd
March 1857.
I, CHARLES PAUVERT, of Chatellerault, Town in the French Empire,
Ecclesiastic, do hereby declare the nature of the said Invention for "CERTAIN
IMPROVEMENTS IN MANUFACTURING STEEL AND CAST STEEL," to be as follows:-
The object of this Invention is, 1st, to purify iron, and to combine it
chemically with carbon by cementation.
2nd, to convert it into first class cast steel of superior qualities whatever
the nature of the iron first employed; I make use of a cement composed of
the materials, and in or about the proportions following:-33 parts by weight
of finely divided charcoal; 33 parts by weight of highly aluminous clay; 33
parts (by weight carbonate of lime or wood ashes, 1 part (by weight) carbonate
of soda, 1 part by weight carbonate of potash. I stratify the iron with this
cement in an ordinary cementing furnace, and heat it in the same manner as
is now generally followed.
I thus obtain a steel possessing all the qualities of that known as German
or "Rives," or shear steel (acier d'Allemagne ou de Rives); the successive

page_text: heats and firings do not cause it to part with the carbon which is intimately
combined with it as in cast or in shear steel. And for this reason carbon,
having but a small affinity for iron, requires, in order to enter into intimate
combination with it, 1st, to be added in an incipient state, 2nd, to be
assisted in its combination by numerous electric currents.
Now these conditions are fulfilled by my process; for 1st, the mutual
reaction of the carbon and the carbonates cause the greater part of the
carbon to assume a molecular state; 2nd, this change of the carbon and of the
carbonates, the action of the red hot iron upon the oxides of aluminium, of
calcium, of potassium, of sodium, with the carbon in the molecular state,
produce or generate numerous sources or currents of electricity. Further,
the earthy and alcaline metals, appearing in an incipient state, greedily absorb
sulphur, phosphorus and the other metalloids. Thus prepared, this steel may
be used as shear steel or German steel (acier d'Allemagne), the properties of
which it possesses.
In order to convert this steel into cast steel, the ordinary processes of fusing
in pots is followed, but with the addition to the metal in the pots from five to
six per cent. by weight of the following mixture, which as far as possible
must be kept from contact with the atmosphere:-4 parts (by weight) dry.
carbonate of soda; 4 parts dry carbonate of potash; 3 parts wood ashes;
2 parts borax; 3 parts oxide of manganese; 4 to 7 parts hydrogenated
charcoal, soot, lamp black, &c. The four parts of carbonate of potash may
have substituted for them two parts of caustic potash. The mixture of these
substances should be effected with care, and their number and proportions
may be varied to suit the nature of the products to be obtained. The reactions
of these substances produce the following effects:-
1st, electric currents.
2nd, complete reduction of the manganese which unites with the steel.
3rd, reduction of the carthy and alcaline metals, and of the borax, which
absorb the metalloids.
4th, disengagement and disappearance of the azoted gases, because potas-
sium, sodium, and calcium, reduced in presence of the steel and of the carbon
in its incipient state, absorb azote to form cyanides of potassium of sodium and
of calcium.
•
5th, formation in steel of crystals larger or of greater volume than by the
ordinary processes of manufacture.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Charles Pauvert in the Great Seal Patent Office on the
1st September 1857.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
PAUVERT, of Chatellerault, Town in the French Empire, Ecclesiastic, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of March, in the year of our Lord
One thousand eight hundred and fifty-seven, in the twentieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Charles Pauvert, Her special licence, that I, the said Charles Pauvert,
my executors, administrators, and assigns, or such others as I, the said Charles
Pauvert, 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 Isle of Man, an Invention for "CERTAIN IMPROVEMENTS
IN MANUFACTURING STEEL AND CAST STEEL," upon the condition (amongst others)
that I, the said Charles Pauvert, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals, should
particularly 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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Charles Pauvert, do hereby declare tho
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement thereof, that is to say:-
The object of this Invention is first, to purify iron, and to combine it
chemically with carbon by cementation. Second, to convert it into cast steel
of superior quality whatever the nature of the iron first employed.
I make use of a cement composed of the materials, and in or about the
proportions following:-33 parts (by weight) of finely divided charcoal; 33
parts (by weight) of highly aluminous clay; 33 parts (by weight) carbonato
of lime or wood ashes; 1 part (by weight) carbonate of soda; 1 part, (by
weight) carbonate of potash. I stratify the iron with this cement in an ordi-
nary cementing furnace, and heat it in the same manner as is now generally
followed. I thus obtain a steel possessing all the qualities of that 'known as

page_text: German or "Rives," or shear steel (acier d'Allemagne ou de Rives). The
successive heats and firings do not cause it to part with the carbon, which is
intimately combined with it as in cast or in shear steel. And for this reason
carbon having but a small affinity for iron requires, in order to enter into
intimate combination with it, first, to be added in an incipient state, second,
to be assisted in its combination by numerous electric currents.
Now these conditions are fulfilled by my process; for first, the mutual
reaction of the carbon and the carbonates causes the greater part of the
carbon to assume a molecular state; second, this change of the carbon and
of the carbonates, the action of the red hot iron upon the oxides of alu-
minium, of calcium, of potassium, of sodium, with the carbon in the mole-
cular state, produce or generate numerous (sources) or currents of electricity.
Further, the earthy and alkaline metals, appearing in an incipient state,
greedily absorb sulphur, phosphorus, and the other metalloids. Thus
prepared, this steel may be used as shear steel or German steel (acier
d'Allemagne), the properties of which it possesses.
In order to convert this steel into cast steel, the ordinary processes of
fusing in pots is followed, but with the addition to the metal in the pots from
five to six per cent. (by weight) of the following mixture, which as far as
possible must be kept from contact with the atmosphere:-4 parts (by weight)
dry carbonate of soda; 4 parts dry carbonate of potash; 3 parts wood ashes;
2 parts borax; 3 parts oxide of manganese; 4 to 7 parts hydrogenated
charcoal, soot, lamp black, &c. The four parts of carbonate of potash may
have substituted for them two parts of caustic potash. The mixture of these
substances should be effected with care, and their number and proportions
may be varied to suit the nature of the products to be obtained. The
reactions of these substances produce the following effects :-
1°. The generation of numerous electric currents.
2°. Complete reduction of the manganese, which unites with the steel.
3°. Reduction of the earthy and alkaline metals, and of the borax, which
absorb the metalloids.
4°. Disengagement and disappearance of the azoted gases, because potas-
sium, sodium, and calcium reduced in presence of the steel, and of the carbon
in its incipient state, absorb azote to form cyanides of potassium, of sodium,
and of calcium.
5°. Formation in steel of crystals larger or of greater volume than by the
ordinary processes of manufacture.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim,-

page_text: First, the manufacture of steel by the means and in manner herein-before
described.
And second, the manufacture of cast steel by the means and in manner
herein-before described.
In witness whereof, I, the said Charles Pauvert, have hereunto set my
hand and seal, this Twenty-seventh day of August, One thousand eight
hundred and fifty-seven.
C. PAUVERT. (L.S.)