IMPROVE-, MENTS IN THE MANUFACTURE OF IRON AND METALLIC COMPOUNDS
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DAVIE MORRIES STIRLING, of Black Grange, in North Britain, Esquire, send
greeting.
WHEREAS I did by petition represent unto Her most Excellent Majesty
Queen Victoria that I had after much study and expence invented "IMPROVE-,
MENTS IN THE MANUFACTURE OF IRON AND METALLIC COMPOUNDS," and Her said
Majesty, being willing to encourage all useful inventions, did issue Her Letters
Patent under the Great Seal of Great Britain, bearing date at Westminster,
the Twelfth day of October, in the year One thousand eight hundred and
forty-eight, in the twelfth year of Her reign, whereby Her Majesty did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Davie Morries Stirling, my exors, adñiors, and assigns, Her special permission,
license, and full power, sole privelege and authority, that I, the said John
Davie Morries Stirling, my exors, adñiors, and assigns, by ourselves, or any.
other persons to whom I or they should grant permission, and to no others,
during the term of years therein expressed, should and lawfully might make,
use, exercise, and vend the said Invention within that part of the said United,
Kingdom of Great Britain and Ireland called England, Wales, the Town of
Berwick-upon-Tweed, and also in all Her Majesty's Colonies and Plantations
abroad; in which said Letters Patent there is contained a proviso, obliging

page_text: me, the said John Davie Morries Stirling, within the space of six calendar
months from the date of the said grant, by a writing under my hand and
seal, enrolled in Her Majesty's High Court of Chancery, particularly to describe
and ascertain the nature of the said Invention, and in what mode it is to be
performed, otherwise the said Letters Patent should become void, as the said
Letters Patent in themselves more fully bear.
i...
16803
NOW KNOW YE, that in 'co
in compliance with the said proviso, I, the said
John Davie Morries Stirling, do hereby declare the nature of my said Inven-
tion, and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement (that is to
say) -
.
In the Specification of my Letters Patent "for certain new alloys and
metallic compounds, with a methed of welding the same and other metals,"
bearing date and sealed at Westminster the Twenty-ninth day of June, One
thousand eight hundred and forty-six, I have described certain modes of
mixing malleable or wrought iron and cast iron in certain proportions, and my
present Invention consists of improvements in the manufacture of malleable
iron, and of certain combinations of malleable and cast iron, and of certain
alloys of malleable iron with other metals, and of cast iron with other metals,
and of malleable and cast iron with other metals.
My improvements in the manufacture of malleable or wrought iron consists,
first, in the addition of malleable iron serap in certain proportions to pig. iron,
cither in the pig bed or otherwise, and the melting or remelting this compound
of wrought and cast iron in any convenient manner, and thereby either
entirely or in a great measure avoiding the process of refining, and at the
same time improving the quality of the iron so produced, of which improve-
ments I shall describe various methods.
First, to a given weight of white iron I add from one-twentieth to one-fifth,
or even one-fourth of its weight of malleable iron scrap. A convenient mode of
doing this is to place the scrap in the hollows moulded in the pig bed of the
blast furnaces; a partial union is thus effected, and the malleable iron scrap
becomes somewhat altered in its nature, by being enveloped in the hot cast iron,
and in consequence losing much of its tenacity, and becoming wholly or in part
brittle, crystalline, or steely. The pigs composed of this mixture of iron are then
to be boiled and puddled, or puddled in the usual manner, as is well understood,
care being taken that the mixture should be thoroughly melted, as by this
means, when the iron afterwards sets, or begins to show a tendency to become
solid, the resulting malleable iron will be uniform in its texture. In the
making malleable iron as heretofore practised, I am aware that malleable scrap

page_text: has been thrown into the puddling furnace both to use up small scrap and (on
the part of the workmen) to hurry solidification, and occasionally also with a view
to improve the character of the iron, but the mixtures after such addition are
not thoroughly incorporated by being melted together. The addition of a
small portion of malleable scrap improves the character of the malleable iron,
which results, and a progressive improvement takes place by increasing such
addition. From the very varying character of cast iron it is impossible to state
a maximum, but I have found that with cast iron of most inferior quality the
addition of somewhat less than a fourth part of its weight of malleable scrap-
has rendered the malleable iron produced therefrom, according to my Invention,
superior to the malleable iron made from the like cast iron refined. Another
mode of making the mixture of malleable and cast iron for conversion into
malleable iron (and one which I prefer where it can be done conveniently) is
to melt the malleable and cast iron in a suitable furnace (air or reverberatory
furnaces answer well) in the proper proportions, according to the nature of the
iron employed, and to run this mixture when melted into the puddling
furnaces in proper charges, or to run the mixture into pigs, slabs, or other
convenient forms. I would remark here that the most convenient and least.
costly mode of making such mixture of malleable and cast iron for any
purpose is to run the hot metal direct from the blast furnace on to the.
malleable scrap contained in a reverberatory or other suitable furnace in which
the malleable scrap may previously be heated, but not to such a degree as to
cause the scrap to adhere together, by which adhesion its solubility in the
cast iron is impeded.) The heat is then to be raised and continued till the
mixed metal has become entirely fluid or is quite melted, and till no solid.
scraps can be felt or observed; such mixed metal is then ready for being at
once run into the puddling or boiling furnace, or into any convenient form,
and I recommend this mode of proceeding, as great economy of fuel results,.
and as the mixed metal is more thoroughly incorporated. I am aware that
puddling furnaces and refining furnaces have been connected with blast
furnaces so as to économise heat, by having the melted metal run into them,
and the connecting suitable furnaces with the blast or other furnace (in which.
iron is made) will be found peculiarly advantageous in obtaining these com-
binations or mixtures of wrought and cast iron.
When a better quality of cast iron than white iron is used I recommend
the addition of a larger proportion of malleable iron, and a tenth may be.
considered in most cases a minimum proportion, and I do not usually add
more than from one-fourth to one-third of the weight of the cast iron
employed. I have found that the nature of the iron should regulate the

page_text: proportion, the richer iron or higher numbers of iron, or that known by the
iame of foundry iron, requiring a greater addition of scrap than the lower
numbers or poorer qualities of iron, or that known as forge iron; but it will
be found that malleable iron made from Nos. 1, 2, 3, and 4 pig, with the
proportion of scrap, is superior to malleable iron generally in most essential
points, ductility, fibrousness, strength, &c., and in the working qualities in the
forge or smithy. Malleable iron so made will also be found to harden more
easily and with more certainty if suddenly quenched when hot than common
malleable iron.
Refined iron may in some instances be combined with malleable iron scrap
for the manufacture of malleable iron therefrom, but the higher price of this
iron and other circumstances (I have found) do not render such combinations
so advisable as those already mentioned. I do not confine myself to any of
the proportions above named. Those I have mentioned I have found to answer
well in the generality of cases; but, as already stated, from the difference in
the cast iron of different districts and of different makes, cases will occur where
a smaller proportion than a twentieth of malleable scrap may be useful, and
where a larger proportion than a third may be found serviceable.
When steel scrap can be easily obtained, the addition of such scrap, either
alone or with malleable iron scrap, will be found to improve the qualities of
malleable iron for certain purposes.
Malleable iron so made is particularly well adapted for such uses as the
upper surface of railway bars, tyres of wheels; &c., and where it is desirable
to have a surface harder than that of common iron, or where it is intended to
have a metal which will harden well by quenching.
To produce malleable iron, or rather an alloy of malleable iron, which is
very much less fibrous and at the same time harder than common malleable
iron, I add to any of the above mixtures for producing malleable iron a
portion of tin, preferring block or grain tin. Such addition may be most
advantageously made in the puddling furnace. I have found that the addition
of tin, in the proportion of a two-hundreth part of the weight of the cast and
wrought iron, produces a marked change in the appearances and qualities of
the resulting malleable iron; but the quantity of tin may be varied, and I have
found that the addition of a one-hundredth part produces a metal which breaks
with a crystalline fracture, but which I have found to work well while hot
under the hammer, in the squeezer, in the rolls, and in the smithy, being close
and fine grained, and having a smooth surface. This compound I particularly
recommend for the upper surface or top bars of rails, and for all purposes
where a metal not liable to laminate is desirable. Bismuth, antimony, and

page_text: arsenic may mike manner be used, and will produce a somewhat similar
effect.
The addition of zinc in the form of metallic zinc, its oxides, carbonates, or
other suitable forms, in a similar manner, as above described, for combining
tin with mixed malleable and cast iron, improves the quality of the resulting
malleable iron made from such mixtures, rendering it brighter in color, cleaner
in surface, and yet retaining its ductility and fibrousness. I find the addition
of calamine (which I believe is the best and most economical form in which
to introduce the zinc) in the proportion of a one-hundredth part of the weight
of the mixed iron employed to be a good proportion, but I do not confino
myself thereto.
The addition of copper to any of the above mixtures of malleable iron and
cast iron for the production of malleable iron hardens the resulting malleable
iron. The quantity of such addition may vary, but I do not recommend a
larger quantity to be added than from a two-hundredth to a one-hundreth part
of the weight of the mixed iron.
.
And I would state, in respect to the use of tin, zine, copper, bismuth, anti-
mony, and arsenic, in addition to their employment when making malleablo
from mixtures of cast and malleable iron, as above explained, I have found
that tin, zinc, copper, bismuth, antimony, and arsenic may be similarly
employed when making malleable iron in the ordinary manner.
The addition of manganese, its oxides, or other compounds, reducible by
heat, when in contact with cast iron, gives the malleable iron made by any of
the above-described methods a more steely character, and will in such instances
be found useful. Such addition of manganese in the form of the black oxide
of commerce, in the proportion of one per cent. of the weight of the mixed
iron employed, renders the puddling process more rapid and hardens the iron
so made. I am aware that manganese has in various forms been added to
iron in the puddling process, I therefore only here point out its addition as
advantageous to the above mixtures of iron when it is desired to obtain the
particular character of malleable iron above mentioned.
The various descriptions of malleable iron made by the above processes
being found to harden more easily and certainly than common iron does when
quenched, I recommend that for many purposes, where a hard surface external
coat or layer is wanted, such iron should be used for that part of the pile or
piles previous to the bar, rail plates, or other forms being rolled, and that the
interior of the pile should be made of common malleable iron, which does not
harden so well by quenching, and which does not lose so much of its fibrous
texture by being quenched as most of the mixtures above described do. By

page_text: this means bars, rails, plates, &c. will be produced, which when quenched
will have a hard exterior surface without having entirely lost the fibrous
structure throughout their whole thickness. Where the object is to have a
bar hard, granular, and crystalline throughout, the pile may be mado entirely
of one or more of the sorts of iron made as above described.
I have stated that iron made from Nos. 1, 2, 3, or 4 pig should not contain
Jess than a tenth of its weight of malleable iron scrap, and my reason for
making this statement is, that such iron as Nos. 1, 2, and 3 pig iron (especially)
when boiled and puddled or puddled alone, or with a small proportion of
malleable scrap, wear out the furnace bottoms more quickly than refined or
white iron.
In all instances where it can be done (that is) where price and other circum-
stances permit), I would recommend the addition of malleable iron scrap, in
the proportion of at least a tenth part of the weight of the cast iron, and
a larger addition will in almost all cases insure a superior iron for most
purposes.
To produce an alloy of zinc and iron I proceed as follows:-Where a
cupola furnace has been used for the melting of either wrought iron or cast
iron, or the mixture of cast and wrought iron, when the charge of the furnace
has been run out I put into the furnace (and I recommend that the blast be
then stopped) a quantity of zinc (depending on the size of the cupola), which
easily melts, and in its melted state passing through the cokes or other fuel
and coming in contact with the sides of the furnace, to which portions of the
previously melted or still melting iron usually adhere, a compound of zinc and
iron is formed, suitable for the purposes to which I apply it. I do not recom-
mend that it should contain less than four or more than seven per cent. of
iron for most purposes, and if it be found on examination to contain more
than about seven per cent. of iron, a quantity of zinc should be added to it to
bring it to about that percentage; or if it should be found to contain less
than four per cent. a proper quantity of an alloy richer in iron is to be added
to bring it to the required proportion. The alloy of zinc and iron so pro-
duced may be advantageously used instead of zinc in the formation of alloys
applicable to many of the purposes for which brass, gun metal, and other
alloys of copper, tin, zinc, and lead are now employed.
To produce an alloy having much the appearance of gold, and having many
of its properties, as relate to the working and engraving of it, and such like, I
take the alloy of zinc and iron, as above described, and add it in the pro-
portion of from one-sixth to one-fourth to an alloy of copper and manganese
(to be hereafter described) when it (that is the latter) is in a melted state, or

page_text: they may be melted together; but in consequence of the volatility of the
zinc I prefer the former mode.
The color and quality of the alloy, which I denominate "British gold,"
may be varied according to the quantity of the alloy of zinc and iron which is
added to the alloy of copper and manganese, herein-after described; and I
find that when about four parts of the alloy of manganese, and copper are
added to one part of the alloy of zinc and iron a metal nearly approaching in
appearance to standard gold is produced. A variation in the above quantities
produces a variation in color, in hardness, and tenacity, and as the iron and
manganese each have the same tendency to harden the compound metal, the
quantity of either or both of these may be varied to suit the several purposes
to which this alloy is to be applied. For instance, for rolling purposes a
smaller quantity of the iron or manganese, or of both, should be used. From
experience I have found the adding the above proportions of the alloy of zinc
and iron to the alloy of copper and manganese, to produce an easily workable
and fine colored metal, possessing both malleability and ductility in an eminent
degree, and capable of taking a fine polish. A very good colored metal may
be obtained by substituting zinc alone for the alloy of zinc and iron, on the
one hand, and on the other, by substituting copper alone for the alloy of
copper and manganese.
To produce an alloy of copper and manganese, I either first melt the
copper, and to the melted copper I add from one two-hundredth part to onc
fiftieth part of its weight of the black oxide of manganese, or an equivalent
quantity of manganese, or of either of its oxides, or of its carburet, or of such of
the salts of manganeses as are susceptible of decomposition and reduction at a
high temperature when in contact with the copper or with carbonaceous
matter, keeping at the same time the surface of the metal covered with a
suitable reducing flux, as is well understood, in order to reduce the oxide or
other compound of manganese to the metallic state, and also to prevent the
access of air to the metal; or I put the copper and the manganese or
compound of manganese, as above described, in the crucible or furnace with
the copper, and raise a sufficient heat to insure their perfect combination by
fusion. The above proportions may be varied.
In all these alloys of copper, zinc, and iron, or of copper, manganese, and
zinc, or of zinc, and iron, with them so small a quantity as one two-hundredth
part of their weight of tin produces an increased degree of hardness, and I
occasionally use as mucli as from two to four per cent. Even a larger addi-
tion of tin may in some cases be, employed with advantage. For some
purposes, as for bearings, and for those parts of machinery exposed to friction

page_text: where gun metal, brass, and other metals and alloys of metals are now used, the
addition of lead to the alloy of iron, zinc and copper, or copper and manganese,
either with or without the addition of tin, has a tendency to prevent the
rubbing surfaces from becoming hot, or at least of diminishing their liability
to heat, and I have found from one to three per cent. useful for this purpose.
The alloy of copper and manganese will be found useful in similar propor-
tions to the required quantity of copper alone, and when this alloy is used
the addition of tin becomes less necessary, and the quantity of iron in the zinc
and iron alloy may be reduced. Bismuth and some other metals have a
tendency to harden alloys of copper, zinc, and iron, and may be used instead of
tin, but I prefer tin, as already specified.
To produce an alloy having the color and many of the properties of silver,
and superior in color, brilliancy of surface; and susceptibility of polish to
other imitations of silver, I employ the alloy of zinc and iron as above
described (instead of zinc) in various proportions with copper and nickel, and
with copper and manganese and nickel, and I find by experience the following
proportions to answer for a variety of purposes:-Ten parts of copper, two
parts of nickel; six parts of the zinc and iron alloy, as above, or eight parts of
copper, two part of nickel, four parts of the zinc and iron alloy. These pro-
portions will be found to answer well for various purposes, and they may be
varied. A much larger proportion of the zinc and iron alloy renders the
compound too hard for rolling in the ordinary manner, but is suitable for
castings where a fine white brilliant metal is wanted. Too much copper
injures the color of the metal, rendering it yellowish, and an excess of nickel
renders it more costly.
For rolling I find the above proportions to answer well, and a metal of even
superior quality is produced by melting together six parts of copper, two parts
of nickel, and four parts of zinc and iron alloy. The nickel and copper
should in all cases be first melted and the zinc and iron alloy added, a suitable
material for covering the mixture (or a reducing flux), as is well understood,
being used. The alloy of copper and manganese may occasionally be substi-
tuted for copper, and the observations above made regarding the alloys of
copper and manganese and of zinc and iron (when treating of British gold)
apply here.
In witness whereof, I, tlie said John Davie Morries Stirling,. have
hereunto set my hand and seal, the Twelfth day of April, One thousand
eight hundred and forty-nine.
J. D. MORRIES STIRLING. (L.S.).

page_text: AND BE IT REMEMBERED, that on the Twelfth day of April, in the
year of our Lord 1849, the aforesaid John Davie Morries Stirling came
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification aforesaid, and all and every thing therein contained and specified,
in form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute made for that purpose.
Enrolled the Twelfth day of April, in the year of our Lord One thousand
eight hundred and forty ning