IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL FUEL
Year: 1869

page_text: LETTERS PATENT to James Dewar, Doctor of Medicine, residing at
Kirkcaldy, in the County of Fife, North Britain, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL FUEL."
Sealed the 1st January 1870, and dated the 1st November 1869.
PROVISIONAL SPECIFICATION left by the said James Dewar at the
Office of the Commissioners of Patents, with his Petition, on the
1st November 1869.
I, JAMES DEWAR, Doctor of Medicine, residing at Kirkcaldy, in the
County of Fife, North Britain, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN THE MANUFACTURE OF ARTIFICIAL FUEL,"
to be as follows:-
I take the refuse or waste of rags, esparto grass, and other fibrous
substances used in the manufacture of paper called paper waste, also
certain varieties of the marine algae, and of the littoral grasses and
other natural grasses, bark of trees, refuse sugar cane, or other fibrous
vegetable substances after reducing them into a more or less pulped
condition separately or in combination, and mix them with coal tar,

page_text: Archangel tar or pitch, coal dross, coal culm, coal, or shale waste,
sawdust, or other refuse of wood, pent, or refuse of peat either separately
or in combination, and I find the product of such combination makes a
useful artificial fuel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Dewar in the Great Seal Patent Office on
the 30th April 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
DEWAR, Doctor of Medicine, residing at Kirkcaldy, in the County of
Fife, North Britain, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the First day of November, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said James Dewar, Her special licence that I, the
said James Dewar, my executors, administrators, and assigns, or such
others as I, the said James Dewar, 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 James
Dewar, 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 James Dewar, do hereby declare
the nature of the said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in aud by the
following statement, that is to say :-
It has long been thought of importance to utilize the large quantities
of coal dross, coal dust (or culm), and other waste coal or shale, and

page_text: sawdust, and other refuse. of wood, peat, and refuse of peat, for the
purpose of artificial fuel, and many plans have been proposed for doing
so and overcoming the difficulties of making the various materials
cohere, and form well into cakes or lumps of artificial fuel, and of
making such artificial fuel retain its form until combustion is completo,
instead of breaking down and running away in a comparatively
powdered or dissolved state, and so to a great extent being lost for
fuel. It has also been desired to find some mode of treatment of the
refuse of rags,, esparto grass, and other fibrous.vegetable substances.used
in and remaining as waste from the manufacture of papar, whereby the
same may be usefully employed. This refuse or waste is at present very
often not only treated as useless, but becomes affensive and injurious.
It however contains a large quantity of pulped fibrous vegetable matter
which may be usefully employed and utilized, as herein-after mentioned..
There is also used in the manufacture of paper, and also in the various.
processes. of bleaching by lime, a considerable quantity of chloride of
lime, from which there. results a proportion of lime waste, which may
also be usefully employed and utilized as herein-after mentioned.
My Invention consists in combining fibrous. vegetable substances in.
a pulped condition with coal tar, Archangel tar, or pitch, coal dross, coal
dust (or culm), coal or shale waste, sawdust, or other refuse of wood, peat,
or refuse of peat, whether separately or mixed, in which combined con-
dition I find that the fibrous vegetable substances cause the tar, coal,
and, other combustible matters. above-mentioned to cohere and retain
their form sufficiently during the process of combustion to make the
artificial fuel which they afford useful and convenient.
When it is desired, to prevent the artificial fuel from burning away
too rapidly, and more particularly in cases in which tar or pitch is used,
the refuse lime waste may be usefully mixed with the other substances
above described.. By mixing the waste lime in this manner combustion
of the fuel is somewhat retarded, and the ashes of the fuel are rendered
more useful and valuable for the purposes of manure and otherwise. The
ashes of paper waste fuel are valuable as manure and otherwise, though
waste lime may not be mixed with the substances above-mentioned.
China clay or other earthy matter employed in the manufacture of
paper may be recovered in the ash of the fuel from paper waste.
The manner in which my Invention is to be performed is as follows:
-I take the refuse of cotton and linen rags, esparto grass, and other

page_text: fibrous vegetable substances which have been used in the manufacture
of paper, and which have been reduced to a pulp in that process, and
which I call "paper waste," or otherwise I tako cotton and linen rags,
esparto grass, littoral, and other grasses, and such varieties of the marine
algae as are of a fibrous character, bark of trees, refuse sugar cane, and
any other fibrous vegetable substances either separately or together and
reduce them into a pulped condition. I next mix the paper waste or
other pulped substances in a moist state (cither separately or together)
with coal tar, Archangel tar or pitch, coal dross, coal dust (or culm),
coal or shale waste, sawdust, or other refuse of wood, peat, or refuse of
peat (either separately or together), and then dry the combination, and
I find that the pulped fibrous vegetable substances cause the other
substances to cohere, and form a valuable artificial fuel, which when
exposed to heat retains its form for a sufficiently long time to admit of
effectual combustion. If the paper waste or other pulped substances
(before being mixed with the other substances) have become dry I bring
the same again into a moist state by mixing the said paper waste or other
pulped substances with water. I further sometimes find it convenient
and useful to dry the foresaid paper waste or other pulped substances for
facility of transport in that state and thereafter by moistening them
as aforesaid I wonder them fit for being mixed with the other substances

page_text: which may be found most convenient.
When I substitute pitch for tar
I pulverize or break down the pitch and mix the pitch to the extent of
about one-fourth of the weight of the other substances used (excepting
the pulped matter) with those other substances, and then proceed as before
mentioned. In either case, that is whether tar or pitch has been used, I
take the combined dough-like product, and dry the same in any of the
manners usually employed by bakers, brickmakers, or potters for drying
dough or clay. By omitting the coal tar or Archangel tar or pitch from
the above combination, or by reducing the quantity thereof, a useful fucl
will be obtained, but of less rapid combustion. I also find that the
pulped fibrous vegetable substances used in combination with coal dross
or coal waste alone makes a useful fuel. I further find that the pulped
fibrous vegetable substances used in combination with sawdust or peat
waste or other refuse of wood alone makes a useful fuel. In either of
the last two cases the pulped fibrous vegetable substance is to be mixed
with the base of coal waste or refuse of wood so as to form a mass
casily workable like dough or clay as aforesaid.
I also mix the refuse of lime or lime waste herein-before mentioned
with the other substances (or some of them) used in forming the fuel in
manner above described, but when I use the lime I prefer to retain a
portion of the tar or pitch in the compound. The proportion of lime to
be used may be varied according as it is desired to produce a fuel
capable of more or less rapid combustion, but I find that one-fourth
part by bulk of the foresaid lime waste added to the pultaceous or
dough-like combined substances produce a convenient and economical
fuel. After the lime waste has been so added I treat the resulting
combination as above-mentioned so as to dry the same, and bring it
into a condition for use as fuel in manner before described. For the
purpose of mixing the various substances used in forming the fuel I
find it convenient to employ a mill or gin ordinarily employed for
mixing brick, earth, or lime. I prefer in every case having the fuel
in a dry condition to facilitate transport, and better to retain for a length
of time its heating qualities, but when it can conveniently be used
immediately or shortly after being made I find it can be usefully
employed for heating purposes even though not dry provided the
cakes or lumps are sufficiently dry to retain their form when used as
fuel.
Having now described the nature of my said Invention, and in what

page_text: manner the same is to be performed, I wish it to be understood that I
do not claim the exclusive use of the said substances except when
employed for the purposes of my Invention, which I hereby declare to
be, the combination of paper or other waste from, the manufacture of
paper and other fibrous vegetable substances in a pulped condition
with coal tar, Archangel tar or pitch, coal dross, coal dust (or culm),
coal or shalo waste, sawdust, and other refuse of wood, peat, and refuse
of peat, whether separately or mixed one with the other, or with all or
any of the other substances in the manner herein-before specified, for
the purposes of artificial fuel.
In witness whereof, I, the said James Dewar, have hereunto sct
my hand and seal, this Twenty-eighth day of April, in, the year
of our Lord One thousand eight hundred and seventy.