A CERTAIN IMPROVEMENT OR IMPROVE- MENTS IN THE MANUFACTURE OF IRON
Year: 1848

page_text: ATTWOOD'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
ATTWOOD, of Wolsingham, in the County of Durham, Esquire, send greeting.
WHEREAS IIer present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eighteenth day of April, in the eleventh year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Charles Attwood, Her especial license, full power, sole privilege and authority,
that I, the said Charles Attwood, my executors, administrators, and assigns,
and such others as I, the said Charles Attwood, my executors, administrators,
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 "A CERTAIN IMPROVEMENT OR IMPROVE-
MENTS IN THE MANUFACTURE OF IRON;" in which said Letters Patent is con-
tained a proviso, obliging me, the said Charles Attwood, by an instrument
in writing under my hand and seal, particularly to describe and ascertain
the nature of my said Invention, and in what manner the same is to be per-
formed, 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.boing
thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles Attwood, 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 (that is to say):-

page_text: My Invention consists in the method herein-described of treating and pre-
paring for smelting, and in afterwards smelting in blast furnaces, such iron ore
as, by reason of its being in a more or less broken, small, comminuted, or pul-
verulent condition, is liable, if smelted in the ordinary way without such treat-
ment or preparation, to slip or run down through the fuel to the bottom of the
blast furnace before it has been properly reduced or duly cemented and com-
bined with carbon; such Invention and method being also applicable to the
bencficial treatment of the kinds of slag or cinder usually smelted for obtaining
the iron which they contain, such as forge cinder, mill cinder, and finery
cinder. The way in which I effect these objects is the following:-I mix such
broken, small, comminuted, or pulverulent iron ore, or cinder, with the coal
required for the purpose of supplying the coke intended to be used in the blast
furnace, and then proceed to coke such coal so mixed with such ore or cinder,
by any known, usual, or convenient method, in order or to the effect that such
ore may become involved in the substance of such coke, and may thereby be
rendered unable to so slip through the fuel in the way above mentioned, or
to descend through the furnace faster than the coke itself, whilst, from being in
such close and continuous contact with it, its reduction and cementation become
much more complete.
But it is necessary to observe, that it is only with such bituminous or caking
kinds of coal as soften, melt, agglutinate, or run together in the process of
burning into coke that such ore, slag, or cinder can be mixed so as to produce
the same effect, seeing that they would not adhere to or remain involved in
the coke produced by any other sort of coal; and also, that in proportion as
the coal employed may possess in a greater degree such bituminous or caking
quality, it is capable of so involving and retaining a greater proportion of such
ore, slag, or cinder, and of still preserving in the coke produced the due degree
of hardness or strength required for blast furnace use. And I would mention,
by way of illustration of this matter, that I have found that such bituminous or
caking coal as is commonly employed in Northumberland and Durham for
making coke will yield a coke of sufficient strength when such coal has been
mixed with from one-fourth to one-third of its own weight of such iron or slag
or cinder, and that in such proportions it will produce very good results in the
blast furnace, the proportion of coke or fuel which the mixture in such cases
contains being found capable of reducing, in addition to the ore so mixed with
it, as much or as large a burden of iron ore, or slag, or cinder, added thereto in
the blast furnace, in pieces of the sizes used in the ordinary method of charging,
as the weight of coke or fuel contained in such mixture would have done
if not so mixed, so that the fuel becomes by being used in my method
improved in the extent of its reducing capability in a very important degree.

page_text: With regard to the degree of comminution, or the size of the particles of the
small iron ore, to which my process may be usefully applied, it extends from
pieces of anywhere about the size of an hen's egg or large walnut down to the
finest dust or powder, but is not of much service in regard to lumps or pieces
bigger or materially bigger than those above mentioned. And with regard to
the size of the pieces or particles of slag or cinder, the same rule is applicable;
but forasmuch as it is not generally to be met with as consisting in any great
proportion of pieces of such small size, it becomes a question of convenience
and economy alone in what circumstances or how far it may be profitable to
break it purposely down to such or near such size, and to adopt cheap and
simple methods of obtaining it in smaller fragments in the process of its pro-
duction. And forasmuch as such slag or cinder cannot be used in large
proportion to the orc employed in the charge or burden of the blast furnace in
the usual mode of working without injurious effects to the quality of the iron,
which do not happen from the use by such usual mode of working of iron ore,
such expense and trouble in reducing the size of such slag or cinder, in order
to employ it according to my method, in which it is less injurious, may be to a
considerable extent profitable.. I have also found that it is advantageous to
crush or otherwise reduce the size of iron ore for the same purpose of using it
by my method in cases where a sufficient supply or proportion of small ore
may not be otherwise obtainable; and as, in proportion to the greater specific
gravity of the iron ore, or slag, or cinder employed, it is in picces of any given
size more disposed to descend too rapidly through the fuel to the bottom of the
furnace, my process is more beneficially applied to such than to ore or cinder of
less specific gravity, such ores as the red hæmatite in particular, which is both
heavy and for the most part small, being such as it is especially suitable to.
The same proportion of lime or flux will be required for any given quantity
of ore or cinder in the blast furnace, where the ore or cider which forms the
burden of the furnace may be in part or altogether treated by my method, as
when the customary method is alone employed, but it need not, and indeed
had better not, be mixed with the coal previous to coking it, seeing that it would
weaken the hardness or strength of the coke, increase the labor, and impede
the process of coking without adequate advantage.
In witness whereof, I, the said Charles Attwood, have hereunto set my
hand and seal, this Thirteenth day of October, in the year of our
Lord One thousand eight hundred and forty-eight.
CHAS (L.s.) ATTWOOD.

page_text: AND BE IT REMEMBERED, that on the same Thirteenth day of October,
in the year above mentioned, the aforesaid Charles Attwood came before, our
Lady the Queen in Her Chancery, and acknowledged the Specification afore-
isaid, and all and every thing therein contained, in form above written. And also
the Specification aforesaid was stamped. according to the tenor of the Statute
in that case made and provided.