MAKING FINE LIGHT BLACK, OF VERY SUPERIOR COLOUR, WHICH, FOR DISTINCTION FROM OTHER BLACKS, WE CALL SPIRIT BLACK, AND A NEW APPARATUS FOR PRODUCING THE SAME
Year: 1821

page_text: . TO ALL TO WHOM THESE PRESENTS SHALL COME, we, THOMAS
MARTIN and CHARLES GRAFTON, of Birmingham, in the County of Warwick,
Printing Ink Manufacturers, and Partners in Trade, send greeting..
WHEREAS His most Excellent Majesty King George the Fourth, by. His
Letters Patent under the Great Seal of Great Britain, bearing date at West->
minster, the Twenty-fourth day of October, in the second year of. His reign,..
did give and grant unto us, the said Thomas Martin and Charles. Grafton,
our executors, administrators, and assigns, His especial licence, full power; sole:
privilege and authority, that we, the said Thomas Martin and Charles:
Grafton, our executors, administrators, and assigns, during the term of years:
therein expressed, should and lawfully might make, use, exercise, and .vend;
our Invention of "MAKING FINE LIGHT BLACK, OF VERY SUPERIOR COLOUR,
WHICH, FOR DISTINCTION FROM OTHER BLACKS, WE CALL SPIRIT BLACK, AND A NEW
APPARATUS FOR PRODUCING THE SAME," within that part of His United Kingdom
of Great Britain called England, Wales, and the Town of Berwick-upon-
Tweed, and also in all His Colonies and Plantations abroad; in which Letters
Patent there is contained a proviso obliging us, the said Thomas Martin and.
Charles Grafton, under our hands and seals, or one of us, under his hand and
seal, to cause a particular description of the nature of our said Invention, and;
in what manner the same is to be performed, to be inrolled in His Majesty's
High Court of Chancery within two calendar months next and immediately!
after the date of the said recited Letters Patent, as in and by the same:
(relation being thereunto had) may more fully and at large appear:

page_text: And whereas it has long been known that large quantities of coal tar were
constantly accumulating at the different gas works, of which little or no use
could be made, and being ourselves engaged in a concern of this nature, it
became an object with us to devise some means of using it; and being con-
vinced that it contained a very large quantity of combustible matter, it
occurred to us that it might be advantageously employed in the manufacture
of lamp black and whereas the bringing of this coal tar into a state in
which it can be used for this purpose, and the apparatus employed for the
same, constitute the object and intention of our said Invention.
NOW KNOW YE, that in compliance with the said proviso, we, the said
Thomas Martin and Charles Grafton, do hereby declare that the nature of
our said Invention is fully described and ascertained in the Plan drawn in the
margin hereof, and in manner and form as follows (that is to say):-
For the purpose before stated, we take common coal tar, and divest it as
much as possible of the ammonical liquor and acid held in solution, as follows:-
We take four casks or other vessels, capable of holding one hundred and thirty
gallons, and put into each of them sixty gallons of the rough or impure tar.
We then add to each of them sixty gallons of strong lime water, and agitate
them together by machinery, or any other convenient mode, 'till the said lime
water is completely mixed with the tar. The vessels are then left at rest for
about six hours, when the tar will be settled at the bottom, and the water may
be drawn off; we then fill up the casks again with hot water, pumped from
the hot well of our steam engine, and agitate as before. This operation of
washing with hot water we repeat three times, suffering the tar to subside
each time, and drawing off as before, allowing twelve hours instead of six
before we draw off the last water, that the whole of the water may have got to
the surface, and we may have little but pure tar at the bottom; but as there
will then be a small portion of water remain combined, which would cause the
tar to crackle and fly about instead of burning freely, we have recourse to a
further process to divest it of this. For this purpose, we have erected a still
(similar to the stills used for distilling spirits of turpentine, and, of course,
forming no part of our Invention), capable of holding about one hundred and
twenty gallons; into this we put forty gallons of the prepared tar, and with a
gentle heat drive off the water and other impurities which the tar holds in
solution. As soon as we perceive the whole of the water is come over, and
there begins to run a fine clear spirit, we stop the distillation; and when a
little cooled, the pure tar is drawn off, and reserved for the purpose of black,
to which this Invention has reference. This purified tar, thus obtained, may
be made into black in the apparatus hereafter described, or may be subjected

page_text: to a further rectification to divest it of the mineral pitch or asphaltum which is
combined with the pure oil and spirit. We prefer the latter process, as the
mineral pitch or asphaltum is only inflamable at a high temperature, which
renders it more troublesome to use, the apparatus requiring frequent cleaning
from the carbonised pitch falling to the bottom and choaking it up. This will
be more fully described when we speak of the apparatus itself. In order to
get rid of the aforesaid mineral pitch or asphaltum, we proceed as follows:→
Having the forty gallons of tar in the still, as before described, instead of
stopping the operation when the spirit begins to come over, we continue the
distillation with a strong heat, and force over the whole of the oil and spirit
contained therein, leaving the residue asphaltum in the still. As the mode of
doing this is well known to every person acquainted with distillation, the
particulars need not here to be described, as they form no part of our Inven-
tion, and may be done in any still capable of bearing a strong heat, to which
a refrigerater or worm tub is. affixed, this Patent being solely for the appli-
cation of these two products, namely, the refined coal tar and coal tar spirits,
to the purpose of black making, which, together with the apparatus employed,
we claim as our exclusive Invention, and which is to be performed as hereafter
described and more fully explained by the Drawings in the margin hereof.
The brickwork A, A, is eighteen feet nine inches long, and three feet wide.
The use of it is to support the main pipe B, B, which rests on the back part of
it and the bonnets C, C, C, in the front. The fireplace seen at the end dis
for the purpose of making a small fire to heat the main pipe B, B, when
burning the purified tar, the fluc running in a direct line underneath, the said
pipe, and so constructed as to heat it to the boiling point, or two hundred and
twelve degrees. The more immediate use of this will be described hereafter.
The main pipe B, B, the end of which is shewn at the back of the orickwork
Figure 1, and the whole in Figure 2, is a cast-iron pipe six inches diameter.
inside, nineteen feet long. The projecting pipes a, a, a, a, the ends of which
are seen in front of the brickwork, and also in Figure 2, are curved pipes,
with the ends turned upwards, as more distinctly shewn in Figure 3. These
pipes project one foot from the main pipe B, B, into which each of them has
a communication by means of a hole drilled through the pipe, and to which
pipe B, B, they are firmly fixed by screws (as shewn in Figure 3 at 6), so as
to form a water-tight joint; the diameter of the hole in these pipes is one inch
and three quarters. To each of these pipes there is a small cup of three
inches in depth to drop into the inside; the cup may be made of strong sheet
iron or copper, with a broad flanch thrown out so as to rest on the top of the
pipe at a.
The diameter of the inside of the cup is one inch and a quarter.

page_text: The bonnets C, C, C, which are for the purpose of receiving the smoke, are
twelve inches diameter at the bottom, fifteen inches in the swell, and tapering
up to six inches at top, where they terminate by a short pipe and elbow to
connect them with the pipe D, D, as shewn at Figure 5. The pipe D,.D. is
the whole length of the brickwork, and tapers from twelve inches dianieter at
the end to eighteen inches in the centre, where it is joined to another
pipe.E, E, of the same size. This pipe may be of any form which suits the
building in which the work is erected, so that there is a distance of about
twenty feet between the pipe D, D, and the box F, F, which box is four feet
square. From the box F, F, there is another pipe G, G, eighteen inches
diameter and thirty feet long, opening into the box H, of the same size as F, F.
From the box H a pipe I rises to, carry the smoke into an upper room, where
the principal part of the apparatus for collecting the black is, and to which it
is connected at the elbow é. The whole of the piping and boxes C, D; E;
F, G, H, and I, should be made of. strong sheet iron or copper; we prefer the
latter, as not being liable to oxidize, which makes it wear considerably longer,
and the black collected is free from scale. The piping is made to part in con-
venient lengths, or to open at the ends, as shewn at fif, f, in order to take
out the black when necessary, and the boxes have the front side to take off for
the same purpose. See g, g, g. The remaining part of the apparatus K, K, K, K,
is of strong canvas formed. into bags three feet diameter and six yards long
each; these bags are nailed at the tops h, h, h, to wood frames, so formed as to
convey the smoke from the mouth of the one into the other, and are again
connected within three feet of the bottom by arms or tubes i, i, i,-i, twelve
inches diameter, formed of canvas, and sewn into the bags so as to unite them
together. k, 'k, k, k, are pieces of wood grooved into the boards 1, 1, 1, 1, to
take out so as to introduce a brush to clean the black from the inside of the
frames.
Having thus laid down the forin and dimensions of the principal part of the
apparatus, it now only remains to describe the mode of producing the fine
black, here called spirit black, from the refined coal tar, and coal tar spirits
before named. In the first instance the pipe B, B, must be placed on an
exact level upon the brickwork, and filled with the purified tar by pouring
into the pipe c, until the tar rises within half an inch of the top of the
pipes a, a, a, a. A fire is then to be made in the fireplace d, and the pipe
At this heat, by holding a lighted stick on the surface
of the tar in the pipes a, a, a, a, it will become ignited, and will in a few
minutes burn freely. The fire may be then withdrawn, as the burning tar
will generally heat the pipe sufficiently to keep up the combustion in the
heated to about 140%.

page_text: whole twenty-four burners, and little more will be wanted than to supply the
pipe regularly with cold tar. This may either be done by a pipe brought from
the tar vessel with a cock placed over the pipe c, or it may be poured in; by
the person employed when wanted, as suits the convenience of the workman.
The pipes a, a, a, a, where the tar is burning, will require frequently to be
stirred round with a strong wire. to clear off the black which will form on the
edges, and to drive down the carbonised tar which forms itself on-the-surface.
By these means the burners may be kept at work for any length of time, or
until the piping is sufficiently full of black to want cleaning. The pipe B, B,
will also require to be emptied out every five or six days, to clear it of the
black and other thick pitchy matter which will subside from the burners.
This is done by taking off the plates m, m (which are screwed tight by means
of four pins and burrs through the flanches, and heating the pipe as before
described, when the whole will run out. The plate may be replaced, and the
whole process repeated; but in order to save this loss of time, and cleaning
the pipe and the fire requisite to heat the tar, at the commencement of each
operation, we prefer using the coal tar spirit obtained as before directed. In
this case we take the small iron cup (see Figure 4), and fill it with coarse
cotton so as to form a wick for each of the pipes a, a, a, a; these being 'put
in their places, the pipe B, B, is filled with the tar spirits as before directed
for the purified tar, only there is no fire necessary, for the wicks, as soon as
properly soaked, will light instantly by applying a candle to them, and will in
a very short time burn freely, giving out a large volume of smoke. The
bonnets C, C, C, C, are placed immediately over these burners, and convey the
smoke into the pipes D and E, and from thence into the box: F. Here a
portion of the coarsest and heaviest black is deposited, and the smoke is again
forced on through the pipe G into the box H, where a second deposit of the
heavier black also remains. It then ascends up the pipe I into the canvas
bagging K, K, K, K, where it continues to pass on according to the direction
of the arrows in the Drawing until it is driven through the whole apparatus.
Here it may be necessary to observe, that the whole of the bags K, K, K,
are not perceptible in the Drawing, as from the very great distance requisite
to carry the smoke, in order to collect the lighter particles of black, it is
necessary to have at least from seventy to eighty of these bags, and if more
the better. The last bag must be left open, or have a pipe affixed to it to
carry off the remaining smoke from the room into the open air. These bags
to be shaken occasionally; and when a sufficient quantity of black is collected
at the bottoms, the bags to be untied and the black taken out for use.

page_text: We do not wish to be understood that the dimensions and arrangement of
these bags, as here laid down, is essential to our Invention; on the contrary,
they may be of any length, and arranged in any form to suit the building in
which they are to be used, so that the smoke is made to pass through them,
and it will pass advantageously for the distance of four hundred yards and
upwards; but at the same time we think this the most eligible form, and, as
such, we have adopted it.