IMPROVEMENTS IN OBTAINING ILLU- MINATING GAS AND OIL
Year: 1866

page_text: xu watter of the Letters Patent granted to GEORGE MCKENZIE, of
Glasgow, in the, County of Lanark, North Britain, Cement Manu-.
facturer, for the Invention of "IMPROVEMENTS IN OBTAINING ILLU-
MINATING GAS AND OIL," bearing date the 15th March 1866,
No. 769.
DISCLAIMER proposed to be filed by the Patentee, the said George
M'Kenzie, in the Great Seal Patent Office, with the Specification to
which the same relates, according to the Statute in that case made and
provided.
WHEREAS since the date of the said Letters Patent, and of the filing of
the Specification thereof, I have been advised that a certain part of the said
Invention is not of such public utility as at the time of filing the said
Specification I verily believed it to be, therefore I desire to disclaim some
parts of the title and of the Specification of the said Invention.
NOW KNOW YE, that I, the said George McKenzie, by and with the
leave of Her Majesty's Attorney-General, do hereby disclaim the following
words, "and oil" contained in the title of my said Invention and Specification,
and occurring in the twenty-third line of page two of the said Specification as
printed by Her Majesty's Printers; also the following words, "and oil"
contained in the thirty-fourth line of page two of the said Specification printed
as aforesaid; also the following words, "at various heats" contained in line
two of page three of the said Specification printed as aforesaid; also the words,
"In carrying out my Invention for the purpose of obtaining oil of improved

page_text: "
SE
"
"quality I proceed precisely as herein-before specified in the case of obtaining
illuminating gas, excepting that I effect the distillation at a lower heat.
." I at present believe that for distilling the oil it is best to begin with a
temperature which will melt lead, and to end with the temperature at
" which melted lead will pulverise paper put into it." It is necessary for the
"oil combined with the coal to be as free as possible from water; and
I prefer to use crude mineral oils of comparatively light specific gravity.
"Various kinds of retorts may be used for distilling the improved oil, but
"I prefer to usc such as are commonly employed in distilling mineral oils.
"The quality and quantity of improved oil obtained will of course vary with
"the qualities of the original oil and coal employed. With medium qualities
"I have obtained fifty-two gallons improved oil from a ton of coal combined
"with thirty gallons of oil," contained in lines four to sixteen of page four of
the said Specification, printed as aforesaid; as also the following words,
"and oil," contained in lines twenty-two and twenty-three of page four of the
said Specification printed as aforesaid.
And in order that the effect of the present Disclaimer may be clearly.slown
and understood I will proceed to repeat the said Specification as proposed to
be hereby altered.
"TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
" MCKENZIE; of Glasgow, in the County of Lanark, North Britain, Cement
"Manufacturer, send greeting."
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", WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
"Patent, bearing date the Fifteenth day of March, in the year of our Lord
"One thousand eight hundred and sixty-six, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
"the said George McKenzie, Her special licence that I, the said George
"McKenzie, my executors, administrators, and assigns, or such others as I,
"the said George McKenzie, 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
66
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 OBTAINING ILLUMINATING GAS," upon the condition.
"(amongst others) that I, the said George McKenzie, 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

page_text: My Invention consists in combining coal with shale oil or other mineral oil,
and in subjecting the mixture to distillation or decomposition at various heats.
By the term "coal "I denote the various kinds frequently termed "bituminous
coals," but I do not include under it the mineral "lignite," which is sometimes
called "brown coal," nor the mineral "anthracite," whilst I may remark that
it will probably not be found economically advantageous to employ the varieties
commonly known as "gas coal" (except, perhaps, mixed with inferior coal,)
in working my Invention.
In practically carrying out my Invention for the purpose of obtaining
illuminating gas in the manner which I at present believe to yield the best
results, but to the precise details of which I by no means restrict myself, I com-
bine the coal and oil in the proportions of thirty gallons of oil to one ton of coal;
I prefer to have the oil and coal as free from water as possible, and I prefer
either to take coal already existing in a pulverised state or as separated by
riddling or sifting, or to reduce the coal to a pulverised state by grinding.
I combine the oil and coal by intimately mixing the oil with the pulverised
coal in any convenient way, preferring to make the combination with the oil
or both oil and coal in a heated state. It is not essential, however, that either
oil or coal should be heated when being mixed. The mixing may be effected
in a mixing or grinding mill, such as is used in grinding mortar or loan. I
do not restrict myself to any particular kind of mineral oil, but I prefer to
take crude shale oil or petroleum, and if such oil as purchased or as manu-
factured for the purposes of my Invention contains volatile oils or water I
prefer to remove these by distilling them off or otherwise before combining
the oil with the coal. When the oil is heated for such a purpose, that is to
say, for removing the volatile oil and water, then I at once combine it with
the coal without allowing it to cool. In some cases the residue known as
"bottoms," obtained in treating crude shale oil in the existing processes of
manufacture and which is left in the still after distilling off the "light" and
"lubricating" oil may be mixed with the crude oil employed in carrying out
my Invention with the view of reducing the aggregate cost of the raw
materials.
My improved gas compound prepared in the manner herein-before described
is treated for the obtainment of illuminating gas precisely like the ordinary
gas coal used for that purpose, that is to say, it is put into gas retorts of
iron or fire-clay such as are at present in use, and the distillation or decom-
position is effected in the ordinary way, it being necessary to remark in con-
nection therewith merely that it is advantageous to employ a strong heat,
never less than a bright red heat, but a white heat or nearly so. A

page_text: carbonaceous residue or coke is left in the retort as with ordinary gas coal, and
being of good quality will by its use or sale reduce the cost of the illuminating
gas.
In carrying out my Invention for the purpose of obtaining oil of improved
quality I proceed precisely as herein-before specified in the case of obtaining
illuminating gas, excepting that I effect the distillation at a lower heat. I at
present believe that for distilling the oil it is best to begin with a temperature
which will melt lead, and to end with the temperature at which melted lead
will pulverise paper put into it. It is necessary for the oil combined with the
coal to be as free as possible from water, and I prefer to use crude mineral
oils of comparatively light specific gravity. Various kinds of retorts may
be used for distilling the improved oil, but I prefer to use such as are
commonly employed in distilling mineral oils. The quality and quantity of
improved oil obtained will of course vary with the qualities of the original
oil and coal employed. With medium qualities I have obtained fifty-two
gallons improved oil from a ton of coal combined with thirty gallons of oil..
Having thus particularly described my said Invention, and the manner in
which the same is to be performed, I have to state that I do not restrict
myself to the precise details herein-before specified, but that what I believe
to be novel and original, and claim as the Invention secured to me by.the
herein-before in part recited Letters Patent is, the combining of coal and
mineral oil to form a compound to be used for obtaining illuminating gas and
oil substantially as herein-before described.
In witness whereof, I, the said George McKenzie, have hereunto set
my hand and seal, this Thirteenth day of September, in the year of
our Lord One thousand eight hundred and sixty-six.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
GEORGE MCKENZIE. (L.s.)