AN IMPROVED ARTIFICIAL MATERIAL SAD DRAR HARDAL MATERIAL FOR PRODUCING GAS TO BE USED FOR ILLUMINATING PURPOSES
Year: 1867

page_text: LETTERS PATENT to John Hamilton, of Glasgow, in the County of Lanark,
North Britain, for the Invention of "AN IMPROVED ARTIFICIAL MATERIAL
SAD DRAR
HARD
Y
Sealed the 10th September 1867, and dated the 18th March 1867.
PROVISIONAL SPECIFICATION left by the said John Hamilton at the
Office of the Commissioners of Patents, with his Petition, on the
13th March 1867.
I, JOHN HAMILTON, of Glasgow, in the County of Lanark, North Britain,
do hereby declare the nature of the said Invention of "AN IMPROVED ARTIFICIAL
MATERIAL FOR PRODUCING GAS TO BE USED FOR ILLUMINATING PURPOSES," to be as
follows, that is to say:-
This Invention consists in combining and admixing finely and minutely
ground or screened bituminous coal with the tar or pitch resulting from the
manufacture of stearine or other residues of palm oil or lard or other vegetable
distillations, which mixture or compound is to be used for the production of
illuminating gas. These residues may be used either separately or together in
the following proportions, viz., from 20 to 40 gallons of residue to one ton or
twenty hundredweights of finely ground or pulverized bituminous coal, but the
Invention is not limited to these proportions, and a small proportion of
peat may or may not be added. The admixture is intimately combined either in
a hot or cold state in a pug mill or other suitable commingling machine, and it
is advantageous to allow the compound after being inixed to remain undis-

page_text: turbed for 24 hours or thereabouts before being placed in the retorts for
distillation, as by being allowed to settle a more complete mixture of the
ingredients will result.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Hamilton in the Great Seal Patent Office on the
10th September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HAMILTON, of Glasgow, in the County of Lanark, North Britain, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Thirteenth day of March, in the year of our Lord
One thousand eight hundred and sixty-seven, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Hamilton, Her special license that I, the said John Hamilton,
my executors, administrators, and assigns, or such others as I, the said
John Hamilton, my executors, administrators, or assigns, should at any
time agree with, and no others, from time to time and at all times there-
after 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 "AN IMPROVED
ARTIFICIAL MATERIAL FOR PRODUCING GAS TO BE USED FOR ILLUMINATING PURPOSES,"
upon the condition (amongst others) that I, the said John Hamilton, by
an instrument in writing under my hand and seal, 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 John Hamilton, 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 state-
ment, that is to say :-
My said Invention consists in combining and admixing ground or screened
bituminous coal with tar or pitch resulting from the manufacture of stearine
or other residua of palm oil or lard or other vegetable distillations, which
mixture or compound is to be used for the production of illuminating gas.
These residua may be used either separately or together in the following pro-

page_text: portions, viz., from 20 to 40 gallons of residua to one ton or 20 cwt. of finely
ground or pulverized bituminous coal. The admixture is ultimately combined
either in a hot or cold state in a pug mill or other suitable commingling machine,
and it is advantageous to allow the compound after being mixed to remain
undisturbed for twenty-four hours or thereabouts before being placed in the
retorts for distillation, as by being allowed to settle a more complete mixture
of the ingredients will result.
And in order that my said Invention may be properly understood I now
proceed to more particularly specify a system or mode under which I carry
the same into practical effect in manner following, that is to say:-
In producing material for the manufacture of illuminating gas under this
Invention I use a portion of ground or pulverized bituminous coal, which I
admix with a portion of one or more of the residua remaining in stills after
distillation has been effected, the residua I prefer to employ being those known
as palm oil, pitch, stearine pitch, and animal pitch, such as the residua from
the manufacture of lard, or I use other similar vegetable and animal residua.
The intimate admixture or combination of these substances I effect in a pug
or pan mill or other suitable mixing machine in the following manner :-The
ground or pulverized coal is placed in the mill or mixing machine, and the
residua are added thereto by pouring them over it, after which the action of
the machine is continued for a sufficient length of time to effect their complete
admixture. It will generally be found necessary to heat the residua before
mixing it with the coal so as to make it as liquid as may be necessary, and, if
desired, both the coal and the residua may be heated to any extent required.
The proportions of coal and residua may be varied according to the bitu-
minous nature of the coal used, as well as the volume and quality of the
gas desired to be produced. In my experiments I have found the admixture
of from 20 to 30 gallons of residua to 20 cwt. of coal yield high and economical
results. I do not, however, limit myself to these proportions, and I prefer not
to admix more than 60 gallons of residua to the 20 cwt. of coal. I sometimes
make use of my Invention for mixing with ordinary coal from which illumi-
nating gas is made, my object in so doing being to improve the illuminating
quality of ordinary coal gas, and I have also found that the addition of ten
per cent. of ground rosin or fusel oil to the residua to improve the result.
The distillation of the admixture herein specified is best effected in a fire-clay
retort at a white heat or thereabouts, the gas being driven off and treated as
ordinary coal gas.
Having now described the nature of my said Invention, and the manner in
or under which the same is or may be used or practically carried into effect,

page_text: I would observe in conclusion that what I consider novel and original and
therefore claim as the Invention secured to me by the herein-before in part
recited Letters Patent is, the combination or admixture of animal and
vegetable residua with pulverized bituminous coal to be used for the production
of illuminating gas.
In witness whereof, I, the said John Hamilton, have hereunto set my
hand and seal, this Thirty-first day of August, One thousand eight
hundred and sixty-seven.
JOHN HAMILTON. (L.S.)