IMPROVEMENTS IN UTILIZING LITHOMARGE, AND IN APPARATUS FOR GRINDING IT AND OTHER SUBSTANCES
Year: 1874

page_text: LETTERS PATENT to Jacob Geoghegan Willans, of 9, St. Stephen's
Crescent, Bayswater, in the County of Middlesex, for the Invention
of "IMPROVEMENTS IN UTILIZING LITHOMARGE, AND IN APPARATUS FOR
GRINDING IT AND OTHER SUBSTANCES.”
Sealed the 14th July 1874, and dated the 7th May 1874,
1
PROVISIONAL SPECIFICATION left by the said Jacob Geoghegan
Willans at the Office of the Commissioners of Patents, with his
Petition, on the 7th May 1874.
I, JACOB GEOGHEGAN WILLANS, of 9, St. Stephen's Crescent,
Bayswater, in the County of Middlesex, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN UTILIZING LITHOMARGE, AND
IN APPARATUS FOR GRINDING IT AND OTHER SUBSTANCES," to be as follows:-
Lithomarge is a soft albuminous mineral of various colours, abundant
in Ireland. It is now used in iron blast furnaces.
My Invention consists, firstly, in utilizing it for certain other purposes
as follows; and, secondly, in the construction and use of an improved
apparatus or machine for reducing it to a fine powder, which apparatus.

page_text: is also adapted for grinding other substances, and which forms part of
my Invention.
Firstly. I use finely divided lithomarge as a substitute for fullers'
earth for the purposes and in the manner the latter is applied in manu-
factures. I further use finely divided lithomarge for mixing with pulp
for the manufacture of paper or pasteboard. I also use finely divided
lithomarge in the manufacture of hydraulic cement, mixing it with lime
and burning the mixture.
When applying it instead of fullers' earth I prefer to have it in a
moist or wet state.
When applying it to pulp for paper or pasteboard I prefer to have it
diffused in water and added in the same way as ochre.
1.
When applying it in the manufacture of hydraulic cement I mix the
finely divided lithomarge with burnt lime in suitable proportions (or it
may be with a sufficiency of carbonate of lime), the lime being also in
a fine state of division, or the materials may be ground together to a
fine state. I prefer to mix dry lithomarge powder with slaked lime
powder and then add water to render the mixture moist or plastic; I
temper it well together and leave it in that condition for some time to
further better combination of the lime with the silica and alumina of
the lithomarge. I afterwards dry and burn the mixture at a suitable
heat, and otherwise treat it as clay and chalk mixture is treated in the
manufacture of Portland cement. Instead of mixing up dry lithomarge
with the lime it may be ground with water and mixed in the wet state,
but I prefer to grind the lithomarge in a dry state.
My Invention consists, secondly, in the construction and use of an
apparatus or machine for reducing to a fine state of division dry litho-
marge and other substances, such as carbonaceous matters for dust fuel
and for foundry blacking, as well as those other mineral and vegetable
substances that are used preferably in a finely ground state, such as
mineral paints and some farinaceous substances.
The apparatus or machine which I employ for these purposes is
similar in character to the usual rotating barrels or cylinders, in which
metal rollers.or balls are placed for crushing or grinding the charge;
but instead of its being when at work a closed vessel my Invention is
to have it sufficiently open to allow a current of air or other gaseous

page_text: fluid to pass into and carry off the fine material as ground (continuously.
or occasionally) without necessarily stopping the machine for with-
drawal of the charge.
I prefer to have one or more openings at each end between the axis
and circumference, or I have the axle hollow and opening into the
machine, or the driving power may be applied at its circumference, and
one or more openings may be at or near the centre; these will facilitate
the charging of the unground material and the withdrawal of it finely
ground without stopping the machine for either purpose.
I prefer to draw or force air through the machine by means of a fan;
this air current will carry off suspended in it the finely ground material,
which may afterwards be collected in a large chamber or any convenient
Its removal will facilitate the grinding of the remainder.
manner.
When grinding soft materials, such as lithomarge, coal, or vegetable
substances, I prefer to have (instead of one or two heavy rollers or balls)
twenty or more small balls or other forms of hard material that will
afford more numerous points of contact and friction.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Jacob Geoghegan Willans in the Great Seal
Patent Office on the 6th November 1874.
:
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JACOB.
GEOGHEGAN WILLANS, of No. 9, St. Stephen's Crescent, Bayswater, in
the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of May, in the year of our
Lord One thousand eight hundred and seventy-four, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,.
give and grant unto me, the said Jacob Geoghegan Willans, Her
special license that I, the said Jacob Geoghegan Willans, my executors,
administrators, and assigns, or such others as I, the said Jacob'
Geogliegan Willans, my executors, administrators, and assigns, should
at any time agree with, and no others, from time to time and at all.
times thereafter during the term therein expressed, should and lawfully:

page_text: might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN UTILIZING LITHOMARGE, AND IN APPARATUS
FOR GRINDING IT AND OTHER SUBSTANCES," upon the condition (amongst
others) that I, the said Jacob Geoghegan Willans,. my executors or
administrators, by an instrument in writing under my, or their, or one
of their hands and seals, should particularly describe and ascertain the
nature of the said Invention, and in what manner the same was to
be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
.
NOW KNOW YE, that I, the said Jacob Geoghegan Willans, do
hereby declare the nature of the said Invention, and in what manner.
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof, that is to say:
-
Lithomarge is a soft aluminous mineral of various colors abundant in
Ireland. It is now used in iron blast furnaces.
My Invention consists, firstly, in utilizing it for certain other purposes
as follows; and, secondly, in the construction and use of an improved
apparatus or machine for reducing it to a fine powder, which apparatus
is also adapted for grinding other substances and which forms part of
my. Invention.
Firstly. I use finely divided lithomarge as a substitute for fullers'
carth for the purposes and in the manner the latter is applied in manu-
factures. I further use finely divided lithomarge for mixing with pulp
for the manufacture of paper or pasteboard; I also use finely divided
lithomarge in the manufacture of hydraulic cement, mixing it with lime
and burning the mixture.
When applying it instead of fullers' carth I prefer to have it in a
moist or wet state.
When applying it to pulp for paper or pasteboard I prefer to have it
diffused in water and added in same way as ochre.
When applying it in the manufacture of hydraulic cement I use it not
with burnt lime as a pozzuolana or trass but for the same purpose that
certain clays and river muds are now employed in the manufacture of

page_text: Portland cement, mixing it intimately with lime or its carbonate, and
burning the mixture.
My Invention consists, secondly, in the construction and use of an
apparatus or machine for reducing to a fine state of division dry litho-
marge and other substances, such as carbonaceous matter for dust, fuel,
and for foundry blacking, as well as those other mineral and vegetable
substances that are used preferably in a finely ground state, such as
mineral paints and some farinaceous substances.
°
The apparatus or machine which I employ for these purposes is
similar in character to the usual rotating barrels or cylinders in which
"metal rollers or balls are placed for crushing or grinding the charge, but
instead of its being, when at work, a closed vessel my Invention is to
have it sufficiently open to allow a current of air or other gaseous fluid
to pass into and carry off the fine material as ground (continuously or
occasionally) without necessarily stopping the machine for withdrawal of
the charge.
In carrying my Invention into effect the following is the arrangement
I prefer: I construct a cylinder of boiler plate of a size proportioned to
the amount of material required to be ground, one of a size to contain
and work when filled to th of its cubic capacity, several hundredweights
of the substance at one time is to be preferred, for it is in working on a
large scale especially that the use of my improved grinding apparatus
will be found advantageous. The cylinder is supported upon rollers"
with its axis horizontal, and it is rotated by means of a pinion gearing
with a toothed ring upon its periphery, the pinion taking its motion
either direct from a steam or motive-power engine, or it may be driven
by ordinary means from any source of power at a distance. To the
interior of the cylinder angle irons are fixed obliquely to ensure constant
movement of the contents of the cylinder as it revolves, the angle irons
forming ribs which tend to lift or carry the material up the side of the
cylinder, and when the material descends it is directed along the cylinder
towards one or other end, according to the inclination of the ribs with
which it comes in contact and the ribs are inclined opposite ways; those
on one half of the circumference are directed towards one end, and
those on the other half towards the other end. In each end of the
cylinder is a central opening; that at one end serves to receive a trunk
for the introduction of the material and for the admission of air, and
•

page_text: 0
that at the other end communicates with another trunk leading into a
depositing room with which an exhaust fan is connected to maintain a
current of air through the apparatus; and the force of this current I
regulate by adjusting the speed of the fan and by dampers or slides in
the air channels, according to the degree of fineness to which I desire
the material to be ground. The feeding trunk enters the cylinder and
passes down with an inclination towards the deepest part of the charge
but not so far down as to touch it or to interfere with the charging of
fresh material or the admission of the air current. The trunk terminates
in a long and comparatively narrow mouth so that the incoming air may
sweep over the whole extent of the surface of the material. The mouth
however must not be so narrow that the pieces of material to be ground
would be liable to stick in it, for it is through this air trunk that the
material is fed in. The material may be shovelled in by a labourer as it
is required, taking care that the cylinder be never filled so far as to
cover the mouth of the trunk so as injuriously to check the entrance
of air.
In addition to the material to be ground the cylinder contains balls
or lumps of iron or steel, or other hard substance, which being agitated
with the material to be ground reduce it to powder. The sizes of these
lumps or pieces I vary according to the hardness of the material under
treatment; if like lithomarge it be comparatively soft the hard balls
or lumps should be numerous and small (say about from lb. to 2lb.
each), preferring some larger than others, and say, together of about the
bulk of the charge of material in operation. As soon as the material
is reduced sufficiently fine by the friction of the hard balls or lumps
upon it the current of air carries it away into the depositing chamber
where it settles, and it is removed from time to time.
I sometimes have a longitudinal opening in the upper part of the
feeding trunk (outside the machine) communicating by means of a
closed channel with the outlet of the fan, so that any fine dust drawn
through the settling chamber by means of the fan will again pass
through the grinding apparatus. In this way the same air may be
used over and over again, which is of importance in case the ground
material might suffer from an excess of moisture or impurity contained
in the air. The feeding opening may be provided with a door.
In place of supporting the cylinder upon rollers it may be mounted

page_text: to revolve upon an axle, and have openings at each end around the axle,
or the axle may be hollow and open into the machine.
In place of exhausting the air from the depositing chamber the air
may be forced through the apparatus, for example, the air may be blown
into the machine through one of the trunks or openings, and find its exit
through the other.
The cylinder may be situate in a chamber into which air is forced
by a fan or other apparatus. Instead of a continuous current of air being
passed through the machine it may be applied occasionally.
:
In place of agitating the materials to be ground with the hard balls
or lumps by rotating the cylinder containing them, they may be agitated
(the cylinder being stationary) by arms upon a revolving axis, but the
other arrangement is the more advantageous.
When lithomarge is ground fine, as it conveniently can be by the
means which I have described, it is suitable for use in place of fullers,
earth for scouring woollen fabrics in the process of manufacture to
remove grease. The ground lithomarge is employed in all respects as
fullers' earth is now employed.
I also, as already mentioned, apply finely ground lithomarge in the
manufacture of paper and pasteboard; I employ it to give body in the
same way that ochre, sulphate of baryta, and other minerals are
employed.
When employing lithomarge in the manufacture of hydraulic cement
I prefer to proceed as follows:-I mix the finely divided lithomarge
with burnt lime (or it may be with a sufficiency of finely divided car-
bonate of lime) in the proportion adopted when river mud is employed
with chalk, the proportions of each being estimated by the dry standard.
The lime also being in the proportion it exists in the chalk in pro-
portions commonly used. The lime I employ also in a fine state of
division; or the materials may be ground together to a fine state. I
prefer to mix dry lithomarge powder with slaked lime powder, and
then add water to render the mixture moist or plastic. I temper it well.
together and leave it in that condition for some time (4 weeks or longer)
to further better combination of the lime with the silica and alumina
of the lithomarge; I afterwards dry and burn the mixture at a suitable
heat (i.e., enough to produce incipient fusion), and I otherwise treat it