IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL FUEL
Year: 1873

page_text: LETTERS PATENT to Henry Preston Thorp, of Elstree, in the County
of Herts, Gentleman, for the Invention of "IMPROVEMENTS IN THE
MANUFACTURE OF ARTIFICIAL FUEL."
Sealed the 15th July 1873, and dated the 29th March 1873.
PROVISIONAL SPECIFICATION left by the said Henry Preston Thorp
at the Office of the Commissioners of Patents, with his Petition, on
the 29th March 1878.
I, HENRY PRESTON THORP, of Elstree, in the County of Herts,
Gentleman, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL FUEL," to be as follows:-
The artificial fuel which forms the subject of my Invention consists
mainly of shale, schist, coal toppings, or other analogous combustible
substances which are found in the neighbourhood of true coal, but differ
in many important particulars from that useful mineral. These sub-
stances are capable of being burnt and giving out a considerable amount
of heat, but for various reasons they have not hitherto been utilized to

page_text: any considerable extent, and they are in fact considered almost a waste
product of coal mining, and mounds or heaps containing thousands of
tons of such substances lie useless in the neighbourhood of many coal
mines.
In carrying out my Invention the shale, schist, or other combustible
substance is ground to a fine powder, and to about 14 parts of this
powder is added from 2 to 3 parts of sawdust or wood chippings. These
materials are mixed with lime water, and the whole is agglomerated into
a pasty mass (capable of being moulded) by the addition of about 4 parts
of pitch or tar. When all the ingredients are well mixed the mass may
be run into moulds, and, if desired, subjected to pressure so as to form it
into blocks or bricks of convenient shape and dimensions for use.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Preston Thorp in the Great Seal Patent
Office on the 27th September 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
PRESTON THORP, of Elstree, in the County of Herts, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-ninth day of March, in the
year of our Lord One thousand eight hundred and seventy-three, in the
thirty-sixth year of Her reign, did, for Herself, Her heirs and successors
give and grant unto me, the said Henry Preston Thorp, Her special
licence that I, the said Henry Preston Thorp, my executors, adminis-
trators, and assigns, or such others as I, the said Henry Preston Thorp,
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 ARTIFICIAL FUEL," upon the condition (amongst
others) that I, the said Henry Preston Thorp, 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

page_text: 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 Henry Preston Thorp, 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 (that is to say) :-
=
The artificial fuel which forms the subject of my Invention consists
mainly of shale, schist, coal toppings, or other analogous combustible
substances which are found in the neighbourhood of true coal, but differ
in many important particulars from that useful mineral. These sub-
stances are capable of being burnt and giving out a considerable amount
of heat; but for various reasons they have not hitherto been utilized to
any considerable extent, and they are in fact considered almost a waste
product of coal mining, and mounds or heaps containing thousands of
tons of such substances lie useless in the neighbourhood of many coal
mines.
In carrying out my Invention, the shale, schist, or other combustible
substance is reduced to a granulated form by being passed between
corrugated rollers, or by crushing in some well known stone crusher,
such as Blake's or Newall's, or it may be reduced to a powder by means
of a Carr's disintegrator. This substance forms the basis of my patent
fuel, and it is by varying the proportions of this powder with the other
ingredients I employ that I obtain fuel suitable for different purposes.
If I desire a quick burning and flaming fuel I take fourteen parts of
shale dust, and add thereto two or three parts of sawdust, wood chippings,
or similar material, and four parts of pitch or tar in a hot state. These
ingredients I mix together in a pug mill, finally adding milk of lime for
the purpose of agglomerating the whole into a pasty mass, in which
form it issues from the pug mill, and is run into moulds and dried, or is
cut up into bricks and subjected to pressure, or formed into blocks of
convenient dimensions and shape as may be most suitable for transport
or for the market.

page_text: parts of wood chippings or small coal, and four parts of pitch, mixed
with milk of lime, as above described.
For a dull red heat, ten parts of shale, six parts of peat, small coal, or
wood chippings, and four parts of clay. In fuel prepared in this manner
the milk of lime is not required.
An excellent fuel for gas making may be prepared by combining
eleven parts shale, five parts peat or small coal, and four parts of pitch
and gas tar in a hot state, and mixed as above described with milk of
lime.
In places where ashes, peat, small coal, or combustible refuse of any 1
kind is more easily obtainable than wood chippings or sawdust, the
former materials may be found preferable to the latter in improving the
quality of the fuel.
Having now described this Invention of "Improvements in the Manu-
facture of Artificial Fuel," and having explained the manner of carrying 1
the same into effect, I claim as the Invention secured to me by Letters
Patent as aforesaid, the combination of shale, schist, coal toppings, or
other analogous combustible substance with sawdust, wood chippings,
ashes, peat, small coal, combustible refuse, tar, pitch, clay, lime, and
chalk, and forming the same into artificial fuel, in the manner herein 2
set forth.
In witness whereof, I, the said Henry Preston Thorp, have here-
unto set my hand and seal, the Twenty-seventh day of September,
in the year of our Lord One thousand eight hundred and seventy-
three.
2