CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF FUEL
Year: 1844

page_text: DOBREE'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SANUEL
DOBREE, of Putney, in the County of Surrey, Esquire, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent, under the Great Seal of Great Britain, bearing date at
Westminster the Seventeenth day of February (One thousand eight hundred
and forty-four), in the seventh year of Her reign, did, for Herself, Her heirs
and successors, give and grant unto me, the said Samuel Dobree, my exe-
cutors, administrators, and assigns, Her especial licence, full power, sole
privilege and authority, that I, the said Samuel Dobree, my executors, admi-
nistrators, and assigns, and such others as I the said Samuel Dobree, my
executors, administrators, and assigns, should at any time agree with and no
others, from time to time and at all times hereafter during the term of years
therein mentioned, should and lawfully might make, use, exercise, and vend,
within that part of Her said Majesty's United Kingdom of Great Britain,
and Ireland called England, Her Dominion of Wales, and Town of Berwick-
upon-Tweed, in the Islands of Jersey, Guernsey, Alderney, Sark, and Man,
and in all Her said Majesty's Colonies and Plantations abroad, the Invention
of "CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF FUEL;" communicated to

page_text: me by my son Cartaret Prianlx Dobree, lately deceased; in which said Letters
Patent there is contained a proviso, obliging me, the said Samuel Dobree,
to particularly describe and ascertain the nature of the said Invention, and
in what manner the same is to be performed, by an instrument in writing
under my hand and seal, and to cause the same to be inrolled in Her said
Majesty's High Court of Chancery, within six calendar months next and imme-
diately after the date of the said in part recited Letters Patent, as in and by the
same, reference being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I the said
Samuel Dobree, do hereby declare the said Invention to consist in a new and
peculiar mode of heating a mixture of coal dust, breeze, cinders, or other matter
of similar nature with pitch or other bituminous substance. Such heating
being performed by means of the following apparatus:-I provide a vessel of
iron or other metal, such vessel being in its conformation and mode of con-
struction capable of containing steam of high pressure. This vessel is
surrounded by an outer vessel, forming what is commonly called a steam
jacket, and this also must be capable of bearing high-pressure steam, and
both the inner and outer vessel must be provided with safety valves and be
formed with a manhole at the top, and also another manhole at the bottom,
and such manholes must have close covers. I provide a steam cock to the
outer vessel or steam jacket, by which high-pressure steam may be admitted
from a suitable boiler, and I form a communication between the outer vessel
or steam jacket and the inner vessel, by means of a cock opening into the
latter from the former which may be opened at pleasure. The outer vessel
is provided with a discharge cock at its lower end or side, for the purpose of
taking off the condensed water of the steam. The operation of the Invention
I describe in manner following (that is to say):-
I take the dust of coal of any description, or breeze, or cinders, or other
matter of similar nature, and I mix such dust or matter with pitch or other
bituminous substance, in the following proportions, or in such proportions as
the combustible character of the dust of coal, breeze, or cinders, and of the
pitch or bituminous may be found to render necessary to form a compound
possessing the best combustible qualities. In general I find the following
proportions of such ingredients to be fitting for the purpose, and useful in
practice; I take for steam fuel from seven-eighth parts, to eleven-twelfth parts
of coal in dust, and this I mix intimately with pitch powdered finely, or other
bituminous matter in the proportion of from one-eighth part to one-twelfth

page_text: part, and I make as perfect a mechanical mixture of these materials as possible
I generate high-pressure steam of a pressure equal to about sixty pounds on
the square inch in the boiler connected with the apparatus, and opening the
cock of communication between such boiler, and the outer vessel or steam
jacket, I admit such steam of high-pressure thereto. The outer vessel or steam
jacket being thus supplied with high pressure steam, the inner vessel being
closed becomes thereby heated; the mixture of ingredients above described is
then thrown into the inner vessel, and the manhole closed down. Slightly
damping the mixture will facilitate the heating; I then open the cock of com-
munication between the inner and outer vessels, and so admit high-pressure
steam to pass from the outer into the inner vessel, and I allow such steam to
pass until a pressure of about six pounds to the square inch is obtained in the
inner vessel; the cock of communication between the inner and the outer vessel
is then shut off, and the steam contained in the inner véssel is allowed to
escape freely; the substances composing the mixture will then be found to be
heated, the pitch or bituminous matter melted or softened, and the entire mass
of the ingredients so amalgamated with each other, that the compound can be
formed into small blocks or portions by pressure, in moulds of such figure as
it may be found expedient to give to such blocks or portions in order to fit
them for convenient application to the purposes of fuel. The said blocks or
forms so produced as above described must then be placed in a hot closet until
the moisture they may still retain shall be evaporated and dried off, when it
is fit for use.
I declare that I claim as the said Invention, the process of heating mixtures
of combustible matters and substances in the proportions herein-above stated,
or in any other suitable proportions by high-pressure steam generally, but
more particularly in a double vessel of such general form and construction, and
of such subordinate arrangements as herein-above described, and the conducting
and aiding such process by the application to it of high-pressure steam, the
particular geometrical form or figure of such vessels being such as shall be
found suitable to the due performance of the said process, and convenient of
construction in practice.
In witness whereof, I, the said Samuel Dobree, have hereunto set my
hand and seal this Eighth day of August, in the year of our Lord
One thousand eight hundred and forty-four.
SAM (L.S.) DOBREE.

page_text: AND BE IT REMEMBERED, that on the Eighth day of August, in the
eighth year of the reign of Her Majesty Queen Victoria, the said Samuel
Dobree came before our said Lady the Queen in Her Chancery and
acknowledged the instrument aforesaid, and all and every thing therein con-
tained and specified, in form above written. And also the indenture aforesaid
was stamped according to the tenor of the Statute made in the fifty-fifth year
of the reign of His late Majesty King George the Third.