IMPROVEMENTS IN THE MANUFACTURE OR VERMARLE CHARCOAT
Year: 1854

page_text: LETTERS PATENT to William Longmaid and John Longmaid, both of
Beaumont Square, in the County of Middlesex, for the Invention of
"IMPROVEMENTS IN THE MANUFACTURE OR VERMARLE CHARCOAT"
Sealed the 21st July 1854, and dated the 3rd February 1854.
PROVISIONAL SPECIFICATION left by the said William Longmaid and
John Longmaid at the Office of the Commissioners of Patents, with their
Petition, on the 3rd February 1854.
We, WILLIAM LONGMAID and JOHN LONGMAID, both of Beaumont Square,
in the County of Middlesex, do hereby declare the nature of our said Inven-
tion for "IMPROVEMENTS IN THE MANUFACTURE OF VEGETABLE CHARCOAL " to be as
follows:-
Heretofore vegetable charcoal has been manufactured by the heat of fire.
when the wood or ligneous matter is in suitable retorts or ovens.
Now our Invention consists of employing wood sawdust or vegetable
matter in a state of dust or subdivision, and in acting on the same with
sulphuric acid with water. The liquid is filtered off or removed, and the
charred dust or powder dried, and, if required, ground to a finer powder.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Longmaid and John Longmaid in the Great Seal
Patent Office on the 3rd August 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
LONGMAID and JOHN LONGMAID, both of Beaumont Square, in the County of
Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria; by Her Letters
Patent, bearing date the Third day of February, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said William Longmaid and John Longmaid, Her special licence,
that we, the said William Longmaid and John Longmaid, our executors,
administrators, and assigns, or such others as we, the said William Long-
maid and John Longmaid, our 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 "IMPROVE-
MENTS IN THE MANUFACTURE OF VEGETABLE CHARCOAL," upon the condition (amongst
others) that we, the said William Longmaid and John Longmaid, by an
instrument in writing under our hands and seals, or under the hand and seal
of one of us, 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 William Longmaid, on behalf of myself
and the said John Longmaid, do hereby declare the nature of the said Inven-
tion, and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement thereof, that is to say :-
Heretofore vegetable charcoal has been manufactured by the heat of fire
when the wood or ligneous matter is in suitable retorts or ovens.
Now our
Invention consists of employing wood sawdust or vegetable matter in a state
of dust or subdivision, and in acting on the same with sulphuric acid with
water. The liquid is filtered off or removed, and the charred dust or powder
dried, and, if required, ground to a finer powder.
Having thus stated the nature of our said Invention, we will proceed to
describe the manner of performing the same.

page_text: We prefer to use sawdust and chips of wood, and we place the same in
vats, and run on dilute acid so as to cover the wood. When the wood is well
saturated, we draw off the acid, and place the wood in a drying chamber,
heated to a temperature of about two hundred and fifty degrees of Fahrenheit's
thermometer, and in this manner the operation is completed. When desired
we grind the charcoal thus produced into a fine powder, and where uniformity
of grain is desired we separate the charcoal by sieves into different degrees of
fineness. The strength of dilute acid we have employed is such as indicates
five degrees of Twaddle's hydrometer, and is the strength we prefer, but we
do not confine ourselves to that strength of acid. We would remark that
although we ordinarily use wood sawdust, vegetable matters in other states
may be employed, but it is convenient that the vegetable substance used should
be in a state of division.
Having thus described the nature of our said Invention, and the manner of
performing the same, we would have it understood that what we claim is, the
manufacture of vegetable charcoal herein described.
In witness whereof, I, the said William Longmaid, have hereunto set my
hand and seal, this Twenty-ninth day of July, in the year of our
Lord One thousand eight hundred and fifty-four.
5
Witness,
S. CARPMAEL.
WILLIAM LONGMAID. (L.S.)