IMPROVE- MENTS IN THE MANUFACTURE OF IRON
Year: 1837

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
NEALE CLAY, of West Bromwich, in the County of Stafford, Manufacturing
Chemist, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Nineteenth day of December, in the first year of Her reign, did,
for Herself, Her heirs and successors, give and grant unto me, the said
William Neale Clay, Her especial licence, full power, sole privilege and
authority, that I, the said William Neale Clay, my exors, adñors, and
assigns, or such others as I, the said William Neale Clay, my exors,
adors, 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 expressed,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon Tweed, and also in all Her said
Majesty's Colonies and Plantations abroad, my Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF IRON;" in which said Letters Patent is con-
tained a proviso that I, the said William Neale Clay, shall cause a particular
description of the nature of my said Invention, and in what manner the
same is to be performed, to be inrolled in Her said 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 being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Neale Clay, do hereby declare the nature of my Invention, and in
the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, reference being had
to the Drawing hereunto annexed, and to the figures and letters marked
thereon, that is to say :-
There may be said to be three classes of iron ore,-
First, the common argillaceous iron stone, generally used in the manufacture
of iron in Great Britain.
Secondly, the rich carbonates of iron containing little carthy matters, which
when roasted part with their carbonic acid, and absorbing oxygen become
(after roasting) oxides of iron.
Thirdly, native oxides of iron, either pure or combined with silicia and in
very small quantities other carthy matters.
And according to the ordinary means now pursued from making iron from
iron ores, it is well known that that description called argillaceous ores are
commonly employed, such, for instance, as are found in the coal fields of
Staffordshire, Wales, Scotland, and in other places; and in making iron from
such ores, they are in the first instance submitted to the process of roasting,
and the iron stone or ore, thus treated, is called "burnt mine," "ronsted
mine," or "roasted ore;" such burnt mine, roasted mine, or roasted ore,
with suitablo fuel and fluxes, is then submitted to the process of smelting
in large blast furnaces, and run therefrom into what are called pigs, or in
some cases directly used for iron castings. In case such pigs are to be
converted into malleable iron, they are submitted to the processes of the refinery
and puddling furnaces, all which is well known, and in extensive practice in
this country; and in some instances, ironmasters have recourse to the mixture
of certain portions of the red and other rich iron ores of Cumberland, Lancashire,
North Staffordshire, and other places, with the roasted argillaceous iron ores
above mentioned, in order to enrich those poorer ores.
But such is the peculiar property of the rich iron ores referred to under the
heads secondly and thirdly, that they are not capable of being manufactured
into iron by the process above stated when used alone, although, I believe,
that some of the rich Lancashire ores are, for particular purposes, and mixed
with a small portion of poor ore at considerable cost, reduced by means of char-
coal in blast furnaces. Now it is well known that the red and other rich ores
above mentioned contain much more iron in a given quantity of ore than the
argillaceous ores mainly employed, and the veins of such rich ore are, in many
places, in great thickness; but up to this present time, the ores under the heads

page_text: secondly and thirdly have not by themselves been brought into practical
working, but have only been partially used, combined with poorer ores in the
manufacture of iron.
Now the first object of my Invention relates to a mode of working such rich
ores, and producing malleable iron therefrom by a very simple process, and at
a very small cost, compared with processes now employed for making iron from
argillaceous iron stone or iron ore.
I will now proceed to describe the process I have pursued, and found to
answer, and which, in combination with the converting of the richer ores on a
practical' scale, constitute my Invention. I take any quantity of the red
Lancashire br Cumberland ore or other ores of a rich character, and break
the larger lumps by means of a pair of rollers or otherwise, to about the
size of walnuts, which I believe to be the best size for working. With
one hundred parts by weight of such broken ore, I mix twenty parts of
clean dry coal ashes or cinders, or of coke, charcoal, charred peat, anthracite
coal, or other suitable carbonaceous matter, broken so as to pass through
a sieve of a half inch mesh. This mixture is to be put into retorts or vessels,
which I prefer to be of a D shape, about seven feet long and eighteen inches
high, and two feet wide, made of clay, fire-bricks, iron, or other suitable
material capable of sustaining bright red heat by daylight. These retorts I
prefer to be fixed horizontally in a chamber, which may be constructed as in
the Drawing annexed at the end of a puddling or other furnace, so that the
otherwise waste heat of the furnace may be employed for heating such retorts
and their contents to a bright red heat, at which degree of heat the contents
should be kept some time. The chamber for the retorts is built suitable for
containing several retorts (according as the puddling furnace is capable of
supporting the requisite degree of heat) between the end of the puddling
furnace and the chimney, leaving a sufficient space so as not to impair
the draught of the puddling furnace; and I prefer that the ends of the
retorts should be so much above the ground that there may be an iron
barrow run alongside to receive the charges of the retorts as they are dis-
charged. By this arrangement, the flames and heated vapours passing from
the puddling furnace heat the retorts or vessels on the exterior without having
access to the iron ore in the retorts. One end of each of the retorts is stopped
with a door in a similar manner to that adopted in retorts for distilling
coal for gas, so that they may be readily opened to discharge, and may be
immediately charged and again closed; for it is desirable to be constantly
working so long as there is sufficient heat and the retorts and furnace
are in proper repair, the capability for which constant succession of charging

page_text: and discharging is an important feature of utility in my process, for it does
not require that the retorts should ever be cooled down, but, as above explained,
so soon as one charge has undergone the process and is discharged, a fresh
charge is to be put into the retort, and there are to be pipes connected with
the retorts to carry off the vapours evolved in the process similarly to gas
retorts in making coal gas, which may be conveyed to the chimney or else-
where, and as is shown in the Drawing hereunto annexed. In charging these
retorts I fill them with the mixture of iron ore and cinder, coke or coal,
above described, until it reaches to the boundary line of the flues which heat
the retorts; I then add two or three shovels full of cinder, coke, &c., and
close the door so as to prevent the ingress of any atmospheric air. In this
condition the retorts are to remain for twelve hours or upwards, the duration
depending on the degree of heat applied; but the completeness of the process
may at any time be ascertained by taking out some of the pieces of ore from
the retorts by means of tongs, and with a file filing the surface of such ore to
ascertain whether it has arrived at the metallic state; a very little practice will
suffice to enable the workman to judge accurately of the process. The
charge, on being drawn from the retorts, may (when the product is to be
made into malleable iron) be immediately conveyed into a puddling or balling
furnace; and if the product appears not to be generally in a metallic state, five
per cent. or more of small anthracite coal, or other carbon, is to be put into
the puddling furnace with it. The prepared iron or product from the retorts
is to be balled in a furnace of the customary description, as if treating
"refined iron" of the ordinary process of manufacture, and it will "come to
nature" very readily, and may be said to be a welding of the many parts into
balls rather than puddling; and after the cinder is well worked out it may be
balled or looped (or by whatever other name the process is called), and taken
to the hammer or rolled according to the will of the operator.
I have here described the retorts as being set in a chamber applied to n
puddling furnace, in order to use the otherwise waste heat; at the same time
I do not confine myself thereto, as a chamber with retorts may be heated by
other furnaces; and although I have mentioned twenty parts of cinder, coke,
charcoal, anthracite coal, or other suitable carbonaceous matter, to one hundred
parts of ore, I do not confine myself thereto. The object is to have sufficient.
I have found that a larger quantity than is really necessary for the process, at
the degree of heat above mentioned, is not prejudicial, but it has fully effected
the object of my Invention. And I would further remark, that although I
have mentioned particular sized and shaped retorts, and their being set in a
horizontal position, I do not confine myself thereto, as the same may be varied,

page_text: provided the character of my Invention, as above explained, is otherwise
retained; and altho' I prefer the using of retorts such as are herein de-
scribed, having the requisite heat applied to the external surface thereof, I
do not confine myself thereto, as large masses of iron ore may be treated
according to my Invention, and a furnace similar to a conical lime kiln may
be employed. In pursuing this mode of carrying out my Invention, I place a
mixture of one hundred parts of ore with sixty parts of coal, coke, or other
suitable carbonaceous matters, or thereabouts, in the kiln, and having fired and
raised the kiln to a very bright red heat as equally as possible, I then prevent
all further ingress of atmospheric air at the lower parts of the kiln by stopping
up the apertures; having thus stopped all admission of air from below, I put
five or six inches of anthracite coal, coke, or other suitable carbonaceous
matter on the surface; by this mode of treatment, the fuel in the ignited kiln,
being deprived of all further supply of atmospheric air, will so act upon the
iron ore as to reduce it into the metallic state; and the progress of such working
may be ascertained by taking out portions from time to time, as explained in
respect to the retorts, and when it is judged that the iron ore has become deoxy-
dized, the charge may be drawn and a fresh one immediately supplied to the
kiln or furnace.
I would, in conclusion, further state, that when it is desired to make
cast iron according to my Invention, I charge the retorts with thirty parts by
weight of the carbonaceous matter or matters above named to one hundred
parts of the rich iron ore, and continue the application of heat for a longer
time, say for half as long again, than for simply reducing the iron to a metallic
state; for in order to make cast iron it is necessary to impregnate it with
carbon to that extent that it will readily melt when taken to the cupola furnace
of an ironfounder, who may then use it as he would the broken pig. iron of
the old process. I would remark, that I am aware that it was several years
back proposed to melt such rich iron ores in pots or crucibles with charcoal or
other carbon in order to produce steel by such process. I do not, therefore,
claim any process of retorts or vessels, or kilns for treating such rich ores with
carbon where smelting is performed. And I am aware that as a chemical fact
it is known that iron may be obtained by cementation from burned argillaceous
ores; and further, it has been proposed to submit "burnt mine,"
mine," or "roast ore," in a practical form according to a system of tests, to the
well-known process of cementation like that pursued in converting iron into
steel in closely cemented vessels, such process of tests requiring the heat to be
gradually raised to the proper high degree of temperature, then retaining the
same to that heat for many hours, and then gradually cooling down the same
" roast

page_text: before drawing the charge by which it was proposed to produce steel and iron
from roasted mine, such process being the subject of a Patent in the name of
John Isaac Hawkins, dated the Fourth day of July, One thousand eight
hundred and thirty-six, but such process of test and cementation would pro-
bably be at much greater cost than reducing the like roast or burnt mine or
ore by the ordinary blast furnace which, as is well known, is the usual mode of
making iron from like materials; and I have mentioned these processes to state
that I lay no claim thereto, for my Invention relates only to the working of
the richer ores, and such as are not reducible by the ordinary means of blast
furnace, and does not relate to the roasted argillaceous ores commonly employed
in the manufacture of iron; and moreover it is not necessary previously to
roast such rich ores as I have above mentioned, and it would only bo an
unnecessary expence so to treat such ores.
In witness whereof, I, the said William Neale Clay, have hereunto set
my hand and seal this 15th day of June One thousand eight