A NEW METHOD OF EXTRACTING IRON FROM ORE
Year: 1819

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
THOMPSON, formerly of Ley Hall, in the County of Salop, and afterwards
of Stanley Castle, Worcestershire, Iron Master and Coal Miner, late of the
King's Bench, Southwark, but now of Charlotte Terrace, Lambeth, Surrey,
send greeting.
WHEREAS His late most Excellent Majesty King George the Third did,
by His Royal Letters Patent under the Great Seal of the United Kingdom
of Great Britain and Ireland, bearing date at Westminster, the Twentieth day
of September, in the fifty-ninth year of His reign, give and grant unto me,
the said John Thompson, my executors, administrators, and assigns, His
especial licence, full power, sole privilege and authority, that I, the said John
Thompson, my executors, administrators, and assigns, during the term of years
therein expressed, should and lawfully might make, use, exercise, and vend
my Invention of "A NEW METHOD OF EXTRACTING IRON FROM ORE," within
England, Wales, and the Town of Berwick-upon-Tweed, in such manner as
to me, the said John Thompson, my executors, administrators, and assigns,
should in our discretion seem meet; in which said Letters Patent is contained
a proviso that if I, the said John Thompson, should not particularly describe
and ascertain the nature of my said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal,
and cause the same to be inrolled in His Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
Letters Patent, that then the said Letters Patent, and all liberties and advan-
tages whatsoever thereby granted, should utterly cease, determine, and become

page_text: void, as in and by the said recited Letters Patent, relation being thereunto
had, may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Thompson, do hereby declare that the nature of my said Invention, and
in what manner the same is to be performed, are particularly described and
ascertained in manner following (that is to say):-
My said Invention consists in adopting an improved method or methods of
extracting and producing iron from iron ore or stone for various manufacturing
purposes, without the intervention of the process of the regular blast or smelting
furnace, and by avoiding the use of which a great saving of fuel, among other
expenses, is effected and produced, and the nature and particulars of my improved
method or methods are as follow:-
The iron ore or stone, either in its raw or calcined state (the latter of which
I prefer), may be pulverized in any convenient way, either by an ordinary
crushing mill, or by two or more pairs of cast-iron rollers worked horizontally,
and placed in a parallel perpendicular direction to each other, so that the
pieces of iron ore or stone that are made to pass between the first pair of
rollers may fall on the second pair of rollers for the purpose of passing between
them, or any greater number of rollers, until the iron ore or stone shall be
sufficiently pulverized, but which I do not consider to be properly effected
while any of the pieces of iron ore or stone shall remain larger than an ordinary
sized hazel nut. The iron ore or stone, so pulverized or crushed, may be sub-
jected to washing or other process, by which the whole metallic parts of the
iron ore or stone may, as far as possible, be collected and separated from the
other particles of which it is composed, but this separation may or may not be
adopted, as the operator shall determine. The iron ore or stone being properly
pulverized, either immediately from a raw or calcined state, I then mix it
either with unburnt or slaked lime, and in the following proportions:-If I use
limestone before it is burnt, about one fourth in weight of such stone to three
fourths in weight of the pulverized iron ore or stone; but if slaked lime shall be
used, then about one sixth in weight of such lime will only be necessary to five
sixths in weight of iron ore or stone. I have also used with effect, and strongly
recommend the introduction of the oxide of manganese as a great auxiliary in
fusion, having, moreover, an affinity to the earthy, flinty, and calcareous parts
of the ore, and tending much to vitrification, but particularly in improving the
quality of the iron, as it is well known to have been thoroughly proved long
ago at iron works in Germany, and I believe this ingredient has already been
made use of with success in the blast furnace in England, but it will be found
much more efficacious in the air furnace. Manganese (the black oxide- of

page_text: which is reckoned the best) I mix with the iron ore, and either with or without
lime, but the former I prefer, about one twentieth or twenty-fifth part in
weight to the aforesaid mixture of the ore and lime. When the foregoing
proportions shall be made and mixed, then I place this mixture of iron ore and
lime (or those together with the manganese, equally well mixed) into an
ordinary air or puddling furnace, observing that these materials are placed on
a layer of coke or charcoal, consisting of one twelfth or one fourteenth part,
or thereabouts, of the united weight of the iron ore and lime previously
described; and every succeeding quantity or layer of mixed iron ore and lime
must be placed on and covered with a like and sufficient layer of coke or char-
coal, excepting the last layer of mixed iron ore and lime, which need not be so
covered with a layer of coke or charcoal. It will be obvious, as the carbonic
quality of both coke and charcoal varies essentially, therefore the proportions
of quantity should vary according. to such quality. I do not confine myself
entirely to the use of coke or charcoal, because any other substance or material
which will produce carbone as advantageously will answer the primary object
for which these materials are to be employed. An air or puddling furnace so
charged with the before-mentioned materials for the purpose of fusing or
melting, it will be advisable to agitate or stir them occasionally with an iron
bar or other proper instrument, not only while the operation of fusing is going
on, but after it is performed, that the whole may be properly fused and sepa-
rated. When the iron is thus fused, the bottom of the furnace must be tapped
to admit the fluid iron to quit the furnace for the purpose of being run or cast.
into any required shape or form; and the scoria or slag may either follow the
fluid iron, or it may be previously removed or disengaged from the fluid iron
by an aperture in the furnace, made immediately above the upper surface of
the fluid iron. But if such fluid iron is required to be left in the furnace for
the purpose of being puddled and prepared for the hammer or rollers, then it
will be improper to tap the furnace at the bottom, but simply at the upper
aperture for carrying off the slag or scoria. I have found great benefit to
result from forming the before-mentioned proportions of pulverized iron ore
and slaked lime, and by the assistance of water, into cakes or balls, previous to
placing them in an air or puddling furnace with layers of coke or charcoal,
instead of placing the mixed pulverized iron ore and lime in loose and less
connected parcels in such furnace for fusion.
From the nature of my Invention it is obvious that the proportions of
the materials must be chiefly governed by the experience of the peculiar
character and qualities of the ores employed, which vary so greatly that
scarcely any two are exactly alike. The same thing likewise applies, in

page_text: perhaps fully an equal degree, to coals, their qualities differing most materially,
so that the proprietor of an iron work, desirous of practising the method of
this Patent, will have at first to vary the proportions of each accordingly, until
he finds the result answer his wishes. The substantial part of my Invention,
or improved method of making iron from ore, therefore, does not consist either
in the materials I use, or in the precise proportions of those materials, as before
described, for the making of iron from iron ore or stone, but in totally avoiding
the use of the common blast and smelting furnace, and substituting the air,
reverberatory, or puddling furnace in its stead, for the making of iron from
iron ore or stone for various manufacturing purposes.
By the application of my improved method or methods, a most important
saving of fuel, and a very considerable reduction of the various expenses
(uavoidably attendant on the old and common method of making, smelting, or
extracting iron) are essentially accomplished.
In witness whereof, I, the said John Thompson, have hereunto set my
hand and seal, this Twentieth day of March, in the year of our Lord
One thousand eight hundred and twenty.`