IMPROVEMENTS IN THE MANUFACTURE OF COMPOUNDS TO BE USED AS FUEL
Year: 1873

page_text: LETTERS PATENT to The Reverend Granville Hamilton Forbes, of
Broughton Rectory, in the County of Northampton, for the Inven-
tion of "IMPROVEMENTS IN THE MANUFACTURE OF COMPOUNDS TO BE USED
AS FUEL."
Sealed the 13th March 1874, and dated the 23rd September 1873.
PROVISIONAL SPECIFICATION left by the Rev. Granville Hamilton
Forbes at the Office of the Commissioners of Patents, with his
Petition, on the 23rd September 1873.
I, The Reverend GRANVILLE HAMILTON FORBES, of Broughton
Rectory, in the County of Northampton, do hereby declare the nature
of the said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF COM-
POUNDS TO BE USED AS FUEL," to be as follows:-
My said Invention is designed to effect a further developement of the
Inventions described in the Specifications of former Letters Patent
granted to me, namely, Nos. 835, 1191, 1204, 1816, and 1832, A.D.
1873.

page_text: The said former Specifications describe compounds of various sub-
stances with tar, pitch, or bituminous matter, which compounds when
burned form a substitute for coal and other fuel; and this use of the
said compounds as fuel may be either the primary or the secondary
object of burning them, the ultimate object being sometimes the manu-
facture of lime or cement, as will be understood by referring to the said
former Specifications.
But according to my present Invention when the said compounds have
not been sufficiently burned to convert them into lime or cement I mix
the unconsumed. portions thereof, with a fresh. quantity of tar or
bituminous matter, so that they may again serve as fuel. I may effect
this second mixture or combination of the aforesaid substances with the
tar or bituminous matter by causing the partially burned bricks, blocks,
or pieces to absorb the same, or I may reduce them to powder and mix
them and the tar or bituminous matter together, and afterwards form
the compound thus made into blocks or balls or the like.
According to the Inventions described in the Provisional Specifications
of Nos. 1816 and 1832 I use coal tar or the tar produced in the
distillation of a mixture of certain quantities of bitumen and common
coal; but according to my present Invention I use either the bituminous
substances above specified or pitch or any similar bituminous substance
or a combination of any or all of them. I also use in certain cases a
small quantity of animal or vegetable oil or fat or fatty matter, in:
combination with these bituminous substances, and the other ingredients
described in the two Specifications aforesaid, namely, No. 1816 and
1832.
'
Another part of my present Invention, relates to the production of
compounds. for use as fuel or in, the manufacture of lime and cement
and other like substances by the addition of peat to the ingredients of
the compounds described in the four last mentioned of the said former
Specifications.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the Rev. Granville Hamilton Forbes in the Great Seal
Patent Office on the 20th March 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, The
Reverend GRANVILLE HAMILTON FORBES, of Broughton Rectory, in the
County of Northampton, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-third day of September, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, 'Her heirs and successors, give
and grant unto me, the said Granville Hamilton Forbes, Her special licence
that I, the said Granville Hamilton Forbes, my executors, administrators,
and assigns, or such others as I, the said Granville Hamilton Forbes, 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 MANUFACTURE OF COMPOUNDS TO BE USED AS FUEL," upon the con-
dition (amongst others) that I, the said Granville Hamilton Forbes,
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 imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Granville Hamilton Forbes, 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:-
My said Invention is designed to effect a further developement of the
Inventions described in the Specifications of former Letters Patent
granted to me, bearing date the 8th day of March, A.D. 1873, No. 835,
the 19th day of May, A.D. 1873, No. 1816, and the 20th day of May,
A.D. 1873, No. 1832.

page_text: The said former Specifications describe a compound or compounds of
various substances with tar, pitch, or bituminous matter, which com-
pounds when burned form a substitute for coal and other fuel, and this
use of the said compounds as fuel may be either the primary or the
secondary object of burning them, the ultimate object being sometimes
the manufacture of lime or cement, as will be understood by referring to
the said former Specifications.
But according to my present Invention when the said compounds have
not been sufficiently burned to convert them into lime or cement I mix
the unconsumed portions thereof with a fresh quantity of tar or
bituminous matter, so that they may again serve as fuel. I effect this
second mixture or combination of the aforesaid substances with the tar
or bituminous matter by causing the partially burned bricks or pieces to
absorb the same, as herein-after more fully described.
The first part of my present Invention relates to improvements upon
the Invention for which Letters Patent, No. 835, March 8th 1873, were
granted to me. In that Invention I have for my object the production
of an article which is at once a good fuel and a source of quicklime. I
thus utilize the heat ordinarily lost in the burning of the material from
which lime is made. This object I effect by combining with this
material enough combustible matter to make a good fuel of the com-
pound, which may be used either as fuel or for the manufacture of
lime.
In carrying out this Invention I mix coal tar, or wood tar, or peat
tar, or mineral tar, or pitch, or other similar bituminous substance or a
combination of two or more of them with chalk, and in some cases with
a small quantity of naphtha or mineral oil. I effect this mixture of the
chalk with the tar, pitch, or other similar bituminous substances by the
process of absorption. In this process I avail myself of the absorbent
nature of chalk to effect a combination of the tar or pitch with the
chalk without reducing it to a powder. I break the chalk into pieces of
a convenient size by hand or machinery. I prefer that no piece should
be more than three or four inches in thickness, but this is not absolutely
essential. I then heat the chalk by means of an oven or in any other
convenient manner to such a degree that the moisture is expelled from
the chalk. It is then put while hot into the tar or other bituminous
substance, and allowed to soak there until it has absorbed a sufficient

page_text: quantity of the tar or pitch for my purpose. If the chalk be heated red
hot, or nearly so, the effect of putting a sufficient quantity of it into the
tar will be to make the latter boil. This will render the tar more liquid,
and will facilitate the operation of absorption very much. The chalk
should be allowed to soak in the liquid until it is sufficiently
penetrated by the latter. I prefer to leave it in the tar some little time
after both are cool, but the length of time it should remain will depend
upon circumstances.
Sometimes the process of absorption will be more rapid than at other
times owing to the varying absorbent power of different kinds of chalk.
The best fuel will of course be made by allowing the chalk to remain in
the liquid until it has become thoroughly saturated by the latter. I do
not restrict myself however to this thorough saturation though I greatly
prefer it. An inferior kind of fuel may be produced by removing the
chalk from the tar before it is thoroughly saturated, or even completely
penetrated by the tar. The hotter the chalk the more tar it will absorb
in a given time. If red hot when put into the tar it will become
thoroughly saturated in the conrse of a few hours.
I sometimes use the above method of absorption, or instead of it I use
the following-The heating of the chalk is omitted, and it is placed in
the tar after having been allowed to dry without artificial heat. If
sufficiently dry it will in time absorb enough tar to make an inferior
fuel, and even when not completely dried the chalk will absorb a
certain amount of the tar.
Another method of effecting the process of absorption which I some-
times use is to place the chalk when sufficiently dry in boiling tar or
pitch without previously heating the chalk, or having heated it only
enough to dry it sufficiently for my purpose.
Another method which I employ is to boil the chalk in the tar or
pitch. After boiling the chalk in the tar or pitch a sufficient time I
allow the chalk to remain in the liquid until it has absorbed enough tar
or pitch for my purpose.
I prefer to use the chalk thoroughly dry, but I do not restrict myself
to the use of it in that state.
I use any of the above methods of absorption, according to the quantity
of the fuel or lime which I wish to produce. When pitch is used.

page_text: instead of tar for the process of absorption it must be rendered liquid by
heat.
In some cases I mix a small quantity of naphtha or petroleum or
other mineral oil, or a mixture of any two or more of them, with the tar
or pitch from one part to four parts of the oil or oils to sixteen parts tar
or pitch before placing the chalk in it, as in the various methods above
described. The effect of the naphtha or mineral oil is to render the tar
or pitch more liquid, and the resulting compound more valuable. But
if the chalk be put into this mixture when red hot there will be danger
of setting the mixture on fire, or if the mixture be heated too much
some portion of the oil will be wasted. It is therefore more desirable
to use the naphtha or mineral oil in the cool process than in the hot
process, but I do not restrict myself only to its use in the former case.
In those cases where limestone is found to be sufficiently porous for
the purpose I sometimes employ the process of absorption in dealing :
with it, but not having the absorbent power of chalk limestone is not
suitable for this purpose.
After removing the chalk from the tar or similar bituminous substance
I leave it exposed to the air for a time in order to dry and season it.
It is then used as fuel or for making lime. When the compound has 2
been burnt, but not sufficiently to convert it into lime, I place the
partially burnt pieces in the tar or similar bituminous substances a
second time and allow them to remain until they have absorbed sufficient
of the liquid for my purpose. For this purpose I use any of the methods
of absorption before specified, and afterwards proceed in the manner 2
above described. I then use the compound a second time as fuel, or I
use it simply for making lime. If necessary I repeat the process of
absorption after burning the fuel a second time.
The second part of my present Invention relates to improvements
upon the Inventions for which Letters Patent, Nos. 1816, May 19th, 3
and 1832, May 20th, A.D. 1873, were granted to me.
In carrying out this part of my Invention I proceed in the first
instance in the manner fully described in the Specifications of the above
named Letters Patent. When the compounds thus described are taken

page_text: chalk or limestone, or a combination of the two, with peat and tar for
the purpose above specified.
In witness whereof, I, the said Granville Hamilton Forbes, have
hereunto set my hand and seal, this Nineteenth day of March, in
the year of our Lord One thousand eight hundred and seventy- &
four
GRANVILLE HAMILTON FORBES. (L.s.)
Witness,
RICHARD PERKINS,
Farmer,
Broughton,
Northamptonshire.