Henry Bessemer.

Sir Henry Bessemer, F. R. S. An autobiography online

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pure iron, mixed with manganese and carbon.

Richard A. Brooman, A.D. 1853. "Producing Castings in Malleable Iron." Manganese
is used with wrought scrap in crucibles with carbon.

J. Leon Talabot, A.D. 1853. "Manufacture of Cast Steel." Blister steel is melted
with oxide of manganese.

John D. M. Stirling, A.D. 1854. "Manufacture of Steel." Cast iron is repeatedly
melted with iron oxides containing manganese.

C. A. B. Chenot, A.D. 1854. "Manufacture of Steel, Iron, and different Alloys." Iron
ore is roasted, pulverised, and converted into a "sponge." s lt is then mixed with manganese,
and fused.

Auguste E. L. Bellford, A.D. 1854. "Manufacture of Steel and Wrought Iron directly
from the Ore." Iron ore is mixed with manganese and other substances, and is roasted. It is
then melted in crucibles.

Charles Sanderson, A.D. 1855. "Manufacture of Iron." Sulphate of iron and manganese
are added to molten iron.

Abraham Pope, A.D. 1856. "Manufacture of Iron." Iron ore, boghead coke, and oxide
of manganese are melted in a reverberatory furnace.

Richard Brooman, A.D. 1856. "Manufacture of Cast Steel." Manganese and other
materials are added to wrought iron to make steel.

John D. M. Stirling, A.D. 1856. "Manufacture of Steel." Manganese is used in the
manufacture of steel from cast iron and iron ore.


Joseph Gilbert Martien, A.D. 1856. "Manufacture of Iron." Manganese is blown into
molten iron.

"William Clay, A.D. 1856. "Manufacture of Wrought or Bar Iron." Uses manganese.

Abraham Pope, A.D. 1856. "Manufacture of Steel." Manganese is used in the
cementation process.

From the foregoing long list of claimants to the use of manganese
in various ways in steel making, it must be evident that a knowledge of
of its beneficial effect was widely known and highly appreciated nearly a
century ago ; but the most prominent, and the most practically
successful, of all these patentees was a Mr. Josiah Marshall Heath, a
civil servant under the Indian Government, who, noticing in the native
Wootz steel -making of India the marvellous effect of manganese,
conceived the idea of producing steel of superior quality from
inferior brands of British iron by its use in the cast-steel process then
extensively carried on in Sheffield. Heath came over to this country,
and obtained a patent, bearing date the 15th of April, 1839, for the
employment of carburet of manganese (that is, manganese in the metallic
state) in the manufacture of cast steel : an invention of very great
utility, as by its use cast steel of excellent quality could be produced
from British iron that had been smelted with mineral fuel. Such steel
possessed the property of welding either to itself or to malleable iron.
The Sheffield cutlers were thus enabled to weld iron tangs on to the
cast-steel blades of table - knives, and also to weld many other similar
articles : a process which was not successfully carried on previous to
the use of metallic, or carburet of, manganese under Heath's patent.

Mr. Heath, in his specification, does not confine his claim to the
use of carburet of manganese in crucible steel melting, but distinctly
claims "the use of carburet of manganese in any process whereby iron
is converted into cast steel." All that Heath claimed lapsed and
became public property when his patent expired, and the right to use
carburet of manganese " in any process whereby iron is converted into
cast steel" became common property by this publication, even if the
patent were invalid. Heath was fully justified in making this general
claim, because the results obtained depended on an inevitable chemical


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law, viz. : whenever metallic manganese, with its powerful affinity for
oxygen, is put into molten iron containing disseminated or occluded
oxygen, a union of the oxygen and the manganese follows as an
inevitable consequence of their strong affinity for each other, wholly
irrespective of the process employed in the manufacture of the iron or
steel so treated.

In consequence of this successful invention of Heath's, no British
iron that has been smelted with mineral fuel is ever made into cast
steel in Sheffield without the employment of carburet of manganese.
In the early days of Heath's invention, he supplied the carburet
in small packages to his licensees ; he made this by the deoxyda-
tion of black oxide of manganese mixed with coal-tar, or other carbon-
aceous matter, in crucibles heated in an ordinary air furnace. This
was a costly process, and as the demand increased he suggested to his
licensees that it would be cheaper to put a given quantity of oxide of
manganese and charcoal powder into their crucibles, along with the
cold pieces of bar iron or steel to be melted. These materials would,
when sufficiently heated, chemically react on each other, and produce
the requisite quantity of carburet of manganese in readiness to unite
with the steel as soon as the latter passed into the fluid state. But
Heath's licensees said, " This is not precisely your patent, Mr. Heath,"
and they claimed the right to carry out this suggestion without
paying him any royalty. This was the cause of some eight or nine
years of litigation, by which poor Heath was ultimately ruined, although
his patent was established by a final decision of the House of Lords
alas ! only too late ; for Heath died a broken-hearted, ruined man,
wholly unrewarded for his valuable invention.

Thus we see that both in the use of a carburet, and also by the use
a mixed powder, consisting of oxide of manganese and carbon, Heath's
process has been successfully and commercially carried on from the date
of his patent, in 1839, up to the present hour.

Now, as my converting process was specially intended to deal with
iron that had been smelted with mineral fuel, it will be readily under-
stood how disastrous it would have been to me, if, by the action of
another patentee, I had been prevented from using manganese ; for


if manganese, in some form or other, were absolutely necessary for the
production of steel of good quality from iron smelted with mineral
fuel, it would follow that if the use of manganese, in all its known
forms and combinations when applied to the Bessemer process, could
be patented, thus becoming the exclusive property of some other persons,
then I should have been rendered utterly powerless, and my invention
could not have been worked without the permission of the holders of
these patents, and I should consequently have been wholly at their mercy.
This part of my narrative turns upon a patent obtained by Mr.
Joseph Gilbert Martien, on September 15th, 1855, about a month before
I took out my first steel patents. Mr. Martien's invention referred to
improvements in the manufacture of iron and steel. He was at that
time engaged at the Ebbw Vale Works, either on the staff of that
company or as an independent experimenter. There would have been
no need for me to refer to Mr. Martien's patent of 1855, but for subse-
quent events with which it was associated. It was really a valueless
patent, and one which found no practical application ; nevertheless, I
must describe it briefly here, and I cannot do better than reprint some
passages from Mr. Martien's specification.

Specification. A.D. 1855. No. 2082.

Martien's Improvements in the Manufacture of Iron and Steel.

This Invention has for its object the purifying iron when in the liquid state from
a blast furnace, or from a refinery furnace, by means of atmospheric air, or of steam, or
vapour of water applied below, and so that it may rise up amongst and completely penetrate
and search every part of the metal prior to the congelation, or before such liquid metal is
allowed to set, or prior to its being run into a reverberatory furnace in order to its being
subjected to puddling, by which means the manufacture of wrought iron by puddling
such purified cast iron, and also the manufacture of steel therefrom in the ordinary manner,
are improved.

In carrying out my Invention, in place of allowing the melted iron from a blast furnace
simply to flow in the ordinary gutter or channel to the bed or moulds, or to refinery or
puddling furnaces, in the ordinary manner, I employ channels or gutters, so arranged that
numerous streams of air, or of steam, or vapour of water may be passed through and amongst
the melted metal as it flows from a blast furnace.

Thus we are distinctly told that the crude metal, after treatment
in the gutter, is made into malleable iron or steel, by puddling in the


ordinary manner, and not by the action of the steam, air, or vapour of
water blown through it. In evidence of this I give another quotation
from Mr. Martien's printed specification.

In treating the liquid or melted metal as stated, either as it directly comes from a blast

furnace or from a finery fire, it is left in the form of pigs, plates, or in a granulated state,

' as may be desired ; or it may be conducted after such treatment directly and without material

loss of heat to a reverbatory or other furnace or furnaces, and there subjected to intense

heat and manipulation, and speedily converted into balls of malleable metal of iron and steel.

Martien was under the impression that he could, in part, supersede
the ordinary finery fire, and render the crude iron more suitable for
puddling, there being no new method or process of making malleable
iron or steel described, or even in the most remote manner suggested,
in this patent. In fact, in the last quotation, he tells us "the metal
is left in the form of pigs, plates (that is, I presume, finer's plate metal),
or in a granulated state, and if it be desired to make it into malleable
iron or steel, the old process of puddling must be resorted to.

Possibly I think probably we should never have heard any more
of Mr. Martien's invention had it not been for my Cheltenham paper
of August, 1856. This paper, as we have seen, was fertile in suggestions
to many would-be inventors. Amongst them in the records of the
Patent Office we find, on September 16th, 1856, the applications for two
patents connected with the manufacture of steel ; one of them was taken
out in the name of Robert Mushet and the other by Joseph Gilbert
Martien. Six days later that is, on September 22nd two other patents
were applied for by Robert Mushet, all four of the patents named being for
the use of manganese in the manufacture of steel ; and therefore they were,
intentionally or otherwise, obstructive patents from my point of view. It
must be remembered that these patents were applied for in the fourth
and fifth weeks immediately following the reading of my paper at
Cheltenham, at which period the whole iron trade of this country
was in a state of extreme agitation and excitement in reference to my
invention, which, at that moment, it was believed would effect a complete
revolution in the iron industry.

Now, at this period, hundreds of men in Sheffield knew perfectly
well that cast steel made from iron that had been smelted with mineral


fuel was so much improved in quality by being alloyed with manganese,
that such iron was never made into cast steel in Sheffield without the
addition thereto of oxide of manganese and carbonaceous matter in the
form of powder, which was put into the crucible or vessel in which cast
steel was made. I have, however, already dwelt at length on Heath's
invention, and have shown that his patents, which had expired long years
before, had given to the world the free use of manganese in steel-making,
and that its general application was a matter of universal knowledge.

Mr. Mushet's specification commences, " Now know ye that I, the
said Robert Mushet, do hereby declare the nature of my said invention,
and in what manner the same is to be performed to be particularly
described in and by the following statement. When cast iron, including
grey and white pig iron and refined metal, has been decarburised or
purified by forcing air through or amongst its particles, either in the
manner described in the specification of Letters Patent, dated the 15th
day of September, 1855, granted to Joseph Gilbert Martien, or in any
other convenient manner, with a view to convert it into malleable iron,
etc." Now, it is clear that Martien did not blow air through molten
iron, in order to convert it into malleable iron, but simply in order to
prepare such cast iron for the after-process of puddling, by which
process, and not by the air blown through it, it was to be converted into
malleable iron. Further, any addition of pitch and oxide of manganese
could not possibly convert into steel iron treated in the manner
described in this patent of Martien so specifically referred to. There
was at that time no commercially-known process of converting pig
iron direct into malleable iron or steel, while still retaining its fluidity,
except that patented by me, to which alone Mr. Mushet's patent could
possibly be applied.

Any attempt to carry into practice Mr. Mushet's process, in the
manner described in his patent of September 16th, 1856, would have been
attended with great danger, and failure must have inevitably followed.
In the manipulation of cast steel a small quantity of oxide of manganese
and charcoal in the form of powder is put into the bottom of covered
crucibles, nearly filled with cold broken-up steel bars. In such crucibles
only a very small amount of atmospheric air is present, consequently the


charcoal at the bottom of the covered crucible is not consumed. But as
soon as a very high temperature is attained the carbon present gradually
deoxydises the manganese, producing a fluid carburet of that metal,
which unites with the steel as soon as the latter is fused. Now, Mr.
Mushet proposed a somewhat different method of procedure. In this
first patent for improvements in the manufacture of steel he stated
that he preferred to use pitch as the carbon element, and having melted
it, to put into the fluid pitch an equal weight of oxide of manganese
in the form of powder, and to stir them well together. This mixture was
to be allowed to cool, after which the brittle mass was to be reduced to
a state of powder, and a quantity equal to one-fifth, or to one-tenth, the
weight of the converted metal was to be used before, during, or after
the conversion. Now, I have found on testing the specific gravity of
this fine powder that a cubic foot of it weighs, as near as may be,
62J Ib. (the same as water) ; hence the minimum charge of one-tenth of
the weight of the contents of an ordinary 5 -ton converter, or 10 cwt.,
would have a bulk of 13.9, or nearly 14, bushels we may call it 13 bushels
while the maximum charge would be 26 bushels. Let us see how such
an addition would behave if put into a Bessemer converter : a vessel
with an interior lining brilliantly red-hot, and containing about 90 to
100 cubic feet of atmospheric air, at a temperature of about 1000 deg.
Fahr. Certainly the first shovelful of such a highly-combustible powder
thrown into this red-hot chamber filled with heated air would result in a
dangerous gas explosion, and the instant rejection of the unreduced
manganese powder present in the mixture. How, then, were the 13
bushels, or the 26 bushels, of this explosive powder to be got into the
red-hot vessel ? For even if it were possible to put in only the smaller
quantity of 13 bushels, of this powder, it would form for a few minutes
a huge bath of molten pitch, and it would require a very bold man to
pour into it 5 tons of molten iron. The whole proposition is so abso-
lutely unpractical that it requires no further comment.

Six days later (September 22nd, 1856), Mr. Mushet applied for
another patent, which did not differ from the use of carburet of
manganese as patented by Josiah Marshall Heath in 1839, for years used

by Sheffield steel manufacturers, and in which patent Mr. Heath claims,



fourthly, " the use of carburet of manganese, in any process whereby
iron is converted into cast steel," to which I have previously referred.
Now, it is obvious that this use of carburet of manganese, even if it
could not have been claimed by Heath in his patent of 1839, had as I
have already stated become, by mere publication, common property
for a period of no less than sixteen years prior to Mr. Mushet's
patent of September, 1856. The only plea that could possibly be
advanced to justify Mushet's claim to a long-ago expired patent,
which had been extensively used, was that the steel into which
this carburet of manganese was to be put had been made by a
different process. Now, let us see to what a deadlock all improved
manufactures would be reduced if once we admit such a claim. Let
us take an example which is strictly analogous. Some fifty or more
years ago a great discovery was made by Mr. Pattinson, of Newcastle,
who invented a most ingenious mode of extracting metallic silver from
ordinary commercial pigs of argentiferous lead. Previous to this, silver
had been almost exclusively obtained from silver ore, amalgamated with
mercury, and afterwards refined, melted, and cast into ingots. There
was no analogy whatever between the old process of extracting silver
and that discovered by Mr. Pattinson. It had long previously been
found that silver, though a very beautiful metal in appearance, was
almost useless, either for the manufacture of utensils or for current
coin, on account of its extreme softness ; articles made from pure silver
being easily bent or misshapen, and coins losing their impression by
wear and abrasion. But it was fortunately discovered that an addition
of 10 Ib. of copper to every 90 Ib. of silver, so hardened and strengthened
the silver as to render it eminently adapted both for the manufacture
of utensils, and also for current coin. This valuable alloy of copper and
silver was accepted by all European Governments as a standard alloy to
be stamped as " silver" and it has been in universal use for many years,
just as steel alloyed with carburet of manganese passes current as steel,
the alloy having also been in public use for many years. But the
silver obtained from lead pigs by Mr. Pattinson's new process, like that
obtained from silver ore, was, of course, too soft to be used in that
state. Now, if some speculative patentee had, on the first announcement


to the world of Mr. Pattinson's great discovery, rushed to the Patent
Office to claim the sole right to put 10 per cent, of copper into silver
obtained by Pattinson's process, under the plea that this silver had been
produced by a new method, it is self-evident that the claim could not
here be substantiated. To admit it would have been simply to destroy
all future great inventions ; the whole idea is too absurd to require
further argument.

On September 22nd, 1856, Mr. Mushet took out yet another patent,
claiming the employment of one of nature's compounds : a compound
which steel - makers have used for the production of steel as far back
as the history of steel-making extends, and which consists of iron found
in the mine associated, or combined, with manganese and oxygen. Such
ore, when smelted, produces a pig iron which contains iron, carbon,
manganese, silicon, and generally phosphorus, sulphur, and other matters
in small quantities, in combination with the iron. In his third patent
Mr. Mushet did not mention my name, or designate any patent of mine,
as the invention which he proposed to improve by the use of spiegeleisen ;
and again the Crown and the public were told that, for the purposes
of his invention, " the iron may be purified by the action of air in the
manner invented by Joseph Gilbert Martien," as will be seen by the
following quotation, reproduced from a printed copy of Mushet's
specification, published by the Commissioners of Patents :

The iron may be purified by the action of air, in the manner invented by Joseph
Gilbert Martien, or in any other convenient manner. The triple compound or material which
I prefer to use is pig or cast iron made from spathose ore, such ore and the pig or cast iron
made from it containing a proportion of manganese, as well as the iron and carbon of which
cast iron is usually composed.

If Mr. Mushet had taken the trouble to examine my early patents
for the manufacture of steel, he would have found that the re-carbura-
tion of converted metal by the addition thereto of molten pig iron, was
perfectly well understood, and had been patented by me more than a
year prior to the date of either of his three manganese patents.
Mr. Mushet also appears to have entirely overlooked my description
of the several modes of making alloys in my process, as set forth in
my patent, dated May 13th, 1856, sixteen weeks prior to the date


of either of his three patents. This description was not given for the
purpose of claiming any such alloys, but, on the contrary, its object
was to disclaim the right to make alloys in my converter of any
metals previously used in the trade to form an alloy with steel, and
by such disclaimer and publication to prevent anyone from obstructing
me in the free use of all such well-known alloys. In order to show
what I really did say in my patent, I give a copy of the paragraph from
my specification.

When employing fluid metal for alloying with malleable iron or steel, I pour it through
an opening in the converting vessel, so that it may fall direct into the fluid mass below;
but when employing metal in a solid form, I put it into the upper chamber through the
door g, and allow it to acquire a high temperature, after which it may be pushed with a
rod, through the opening d, into fluid iron or steel ; and when using salts or oxides of
metals for the purpose of producing an alloy or mixture with the iron or steel, I prefer to
introduce such salts or oxides in the form of powder at the tuytres, or to put them into the
vessel previous to running in the fluid metal. I would observe, that I am aware that zinc,
copper, silver, and other metals have before been combined with iron and steel otherwise
manufactured, I therefore make no general claim thereto.

This paragraph clearly points out how such alloys are to be made,
and I mention as examples, silver alloys, once used and greatly esteemed
as " silver steel "; also alloys of zinc, patented as a detergent to carry
off phosphorus from steel ; I also mention copper as used in stereo
metal for the manufacture of guns in Austria, and other metals
heretofore used in steel-making. Surely, after I had thus published
and disclaimed the use of any alloys previously used, no one could
obtain a valid patent for alloying steel in my process with metals used
to alloy steel then in common use.

The result of my early experiments in re-carburising confirmed the
view I had taken from the first, viz., that it was best to stop the
process as soon as steel of the proper quality was arrived at, for the
continuation of the blowing process until malleable iron was obtained,
had the disadvantage of consuming from 2 to 3 per cent, more
iron than when steel was made ; and, what was still worse, the metal
got very much overcharged with oxygen, causing violent ebullition in
the mould. I had an idea that this occluded oxygen could be got
rid of without any addition to the metal. I had noticed that when super-


oxydised molten malleable iron came in contact with the cold-iron mould, it
boiled and threw off large quantities of gas, as its temperature was reduced,
the action being similar to that which takes place in the cooling of large
masses of molten silver, which sputter and make a sort of little volcanic
mound on the top of the ingot, owing to the spontaneous disengagement
of occluded oxygen. In the case of steel, this throwing off of carbonic
acid, or carbonic oxide, gas was a source of great unsoundness in ingots,
and appeared to be a very important subject for investigation. I
consequently had a small apparatus constructed, with a view of seeing
how far this gaseous matter could be prevented from escaping in the
form of bubbles by being surrounded with a dense atmosphere, to
suppress ebullition ; and also how far it could be removed by con-
siderably lowering the pressure of the surrounding atmosphere, thus
favouring ebullition and the removal of the gas from the metal.

I may here mention, incidentally, that these experiments were the
starting-point of my patents for casting under gaseous pressure, and

Online LibraryHenry BessemerSir Henry Bessemer, F. R. S. An autobiography → online text (page 26 of 38)