IMPROVEMENTS IN THE TREATMENT AND PURIFICATION OF PLUMBAGO FOR THE MANUFACTURE OF CRUCIBLES AND OTHER FIREPROOP ARTICLES, AND IN APPARATUS EMPLOYED THEREIN
Year: 1863

page_text: LETTERS PATENT to Thomas Vaughan Morgan, of Battersea Works,
in the County of Surrey, Crucible Manufacturer, for the Invention of
"IMPROVEMENTS IN THE TREATMENT AND PURIFICATION OF PLUMBAGO FOR
THE MANUFACTURE OF CRUCIBLES AND OTHER FIREPROOP ARTICLES, AND IN
APPARATUS EMPLOYED THEREIN."
Sealed the 7th June 1864, and dated the 9th December 1863.
PROVISIONAL SPECIFICATION left by the said Thomas Vaughan Morgan
at the Office of the Commissioners of Patents, with his Petition, on the
9th December 1863. .
I, THOMAS VAUGHAN MORGAN, of Battersea Works, in the County of Surrey,
Crucible Manufacturer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN THE TREATMENT AND PURIFICATION OF PLUMBAGO FOR THE
MANUFACTURE OF CRUCIBLES AND OTHER FIREPROOF ARTICLES, AND IN APPARATUS
EMPLOYED THEREIN," to be as follows:-
My Invention relates to improvements in the treatment and purification of
plumbago for the manufacture of crucibles and other fireproof articles, and in
the apparatus employed therein, the object being to remove the various
impurities which are found associated with plumbago, more particularly iron
and lime and their compounds.
In the first place I prepare the plumbago for subsequent operations by
passing it through a mill, by which it is ground into small particles, and then
to remove iron and its compounds one method which I adopt is as follows:-I

page_text: place the granular impure plumbago in a close oven or retort, either alone or
mixed with other carbonaceous matter and bring the charge to a low red heat.
By this means after a short time the various compounds of iron become con-
verted into a magnetic protocarbide of iron, which I afterwards withdraw by
magnetic or electro-magnetic action.
The arrangement of apparatus which I employ for effecting this object is
formed by placing an endless band of cloth of any required dimensions upon
two rollers which work horizontally together, or nearly so. Over this endless
band and near one of its rollers a hopper is fixed, into which the granular
plumbago is placed, whence it passes through a narrow opening at the bottom
in a thin layer upon the moving endless band. Close above this one or
more endless chains of magnets are carried upon drums; these magnets
attract the magnetic impurities and carry them into receivers placed on each
side of the endless band, the pure plumbago passing onward with the band
over one of the drums falls into its receiver.
Another method by which I remove iron and its compounds from the
granular plumbago consists in heating it nearly to redness and then passing the
current of chlorine through it. The chloride of iron thus formed is then
washed away with water.
Of lime and its compounds I remove the sulphate of lime by first bringing
the material to near a red heat, whereby the salt of lime becomes changed
into the sulphuret of calcium, which is then readily washed away in hot water
as hydrosulphuret of lime. Where carbonate of lime is the impurity, I ac
upon it by dilute hydrochloric acid, and wash away the soluble salt.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Vaughan Morgan in the Great Seal Patent Office
on the 9th June 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
VAUGHAN MORGAN, of Battersea Works, in the County of Surrey, Crucible
Manufacturer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of December, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-seventh year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Thomas Vaughan Morgan, Her special licence, that I, the
said Thomas Vaughan Morgan, my executors, administrators, and assigns,

page_text: or such others as I, the said Thomas Vaughan Morgan, 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 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 THE TREATMENT AND
PURIFICATION OF PLUMBAGO FOR THE MANUFACTURE OF CRUCIBLES AND OTHER
FIREPROOF ARTICLES, AND IN APPARATUS EMPLOYED THEREIN,' upon the condition
(amongst others) that I, the said Thomas Vaughan Morgan, 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 Thomas Vaughan Morgan, do hereby
declare the nature of my said Invention, and in what manner the same is
to be performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the Drawings hereunto
annexed, that is to say:-
My Invention relates to improvements in the treatment and purification of
plumbago for the manufacture of crucibles and other fireproof articles, and
in the apparatus employed therein, the object being to remove the various
impurities which are found associated with plumbago, more particularly iron
and lime and their compounds.
In the first place I prepare the plumbago for subsequent operations by
passing it through a mill, by which it is ground into small particles, and then
to remove iron and its compounds one method which I adopt is as follows:-
I place the granular impure plumbago in a close oven or retort, either alone or
mixed with other carbonaceous matter, and bring the charge to a low red heat.
By this means after a short time the various compounds of iron become con-
verted into a magnetic protocarbide of iron, which I afterwards withdraw by
magnetic or electro-magnetic action.
The arrangement of apparatus which I employ for effecting this object is
formed by placing an endless band of cloth of any required dimensions upon
two rollers, which work horizontally together, or nearly so, over this. endless
band, and near one of its rollers a hopper is fixed, into which the granular
plumbago is placed, whence it passes through a narrow opening at the bottom
Close above this one or more
in a thin layer upon the moving endless band.

page_text: endless chains of magnets are carried upon drums; these magnets attract the
magnetic impurities and carry them into receivers placed on each side of the
endless band, the pure plumbago passing onward with the band over one of
the drums, falls into its receiver.
Figure 1 of the accompanying Drawings is a sectional elevation, and
Figure 2 a plan, of a magnetic machine or apparatus by which that part of my
Invention relating to the removal of iron impurities from plumbago after they-
have been rendered magnetic or susceptible of receiving magnetism. The
same letters refer to like parts in each Figure.
a is a strap by which motion is conveyed from any suitable source to the
driving pulley b fixed on a shaft carried by the bracket g; c and d are bevelled
cogged wheels which gear into each other and carry round the upright shafts
e, e, supported in the brackets g. On the top of these shafts are secured
horizontally the polygonal wheels q, q, which, as they revolve, give motion to
the endess chain of magnets f; these pass between brass flanges r, r, and are
thereby held in their proper positions; h is a strap passing round a pulley on
the driving shaft, and giving rotation to the roller i at one end of the frame;
another similar roller i¹ is fixed at the other end of the frame. Around these
rollers an endless web of cloth k is placed; this traverses in the direction of
the arrows beneath the slit or opening 7 in the bottom of the hopper m, which
is supported by the standards n, n, fixed on the frame u, u. The granulated
plumbago being placed in the hopper, is carried therefrom in a thin layer, and
passes under the chain of magnets; the iron impurities are withdrawn by
attraction and conveyed to the brushes t, t, which sweep them off into the
boxes 8, 8.
The pure plumbago is carried on by the cloth over the roller i,
under which the scraper o causes it to fall into the box p.
Figure 3 shews a mode in which the chain of magnets is made by means of
the intermediate brass connections w and bolts a, a, N being the north pole
of one magnet and S the south pole of the other, a similar arrangement being
continued throughout the series. In place of permanent magnets, electro-
magnets may be used by forming suitable connections with any convenient
source of electricity.
Another method by which I remove iron and its compounds from the
granular plumbago consists in heating it nearly to redness and then passing a
current of chlorine through it. The chloride of iron thus formed is then
washed away with water.
Of lime and its compounds I remove the sulphate of lime by first bringing
the material to near a red heat, whereby the salt of lime becomes changed
into the sulphuret of calcium, which is then readily washed away in hot water

page_text: as hydrosulphuret of lime.
Where carbonate of lime is the impurity, I
act upon it by immersion in dilute bydrochloric acid and wash away the
soluble salt.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim,-
First, treating and purifying plumbago by means of magnetic or electro-
magnetic apparatus, arranged in manner herein-before described.
Second, the mode described of treating plumbago in order to render the
iron impurities contained in or mixed with it susceptible of magnetism.
Third, the purification of plumbago by a current of chlorine.
And, fourth, the method herein-before described for the removal of sulphate
of lime or carbonate of lime from plumbago.
In witness whereof, I, the said Thomas Vaughan Morgan, have hereunto
set my hand and seal, this Eighth day of June, One thousand
eight hundred and sixty-four.
THO. VAUGHAN MORGAN. (L.B.)