CERTAIN IMPROVEMENTS IN THE PRODUCTON OR MANUFACTURE OF Gas
Year: 1824

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HOLT IBBETSON, of Smith Street, Chelsea, in the County of Middlesex, Esquire,
send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Fifteenth day of May, in the fifth year of His reign, did,
for Himself, His heirs and successors, give and grant unto me, the said John
Holt Ibbetson, His especial licence that I, the said John Holt Ibbetson,
my exors, admors, and assigns, or such others as I, the said John Holt
Ibbetson, my exors, admors, and assigns, should at any time agree with,
and no others, from time to time and at all times during the said term therein
expressed, should and lawfully might make, use, exercise, and vend,. within
England, Wales, and the Town of Berwick-upon-Tweed, my Invention of
"CERTAIN IMPROVEMENTS IN THE PRODUCTON OR MANUFACTURE OF Gas;" in
which said Letters Patent there is contained a provisó obliging me, the said
John Holt Ibbetson, by an instrument in writing under my hand and seal,
particularly to describe and ascertain the nature of my said Invention, and in
what manner the same is to be performed, and to cause the same to be
inrolled in His Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters Patent,
reference being thereunto had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
John Holt Ibbetson, do hereby declare that the nature of my said Invention,
and the manner in which the same is to be performed, are particularly described
and ascertained in and by the Drawing hereunto annexed, and the following
description thereof, that is to say :-
I do hereby declare that my Invention of Certain Improvements in the
Production or Manufacture of Gas consists in the following process, which will
be more fully understood by reference to the accompanying Drawing, which
represents a vertical section of what I denominate my decomposing apparatus.
In that Drawing a is an iron frame and door leading into the top part of the
fireplace, and by this entrance the fire is supplied with fuel, 6 is an opening
into the extreme top part of the fireplace for the admission of the air requisite
for the combustion of the fuel. c is an iron frame and door, shewn by dots,
leading to the bottom part of the fireplace, which opening is for the purpose of
lighting the fire. d is an iron frame and door to the ash pit. The flues from
the fireplace are marked j, j,j, j, the entrances to them being below the grating
at the bottom of the fire. The area between the flues and fireplace may be
called the decomposing chamber. h is an iron door opening into it at the top,
through which the coals or other combustible substances are introduced for
decomposition; the frame of this door must be fixed firmly, and the door made
to close air-tight by luting. e, e, are openings into the lower parts of this
chamber for the purpose of withdrawing ashes or such other refuse, and these
openings are fitted with iron frames and doors, as they must be kept closed
when the process of decomposition is going on, and luted air-tight; and the
circular aperture f, on the right hand, the mouth of a pipe (made of retort
earth) opens to convey the steam of water; and at g, on the other side, there
is another opening for the same purpose. The pipe which passes through this
opening (9) reaches to the opposite side of the chamber. It is made of retort
carth, and the steam escapes from it through holes in the sides and bottom part.
i is the mouth of a pipe leading from the bottom part, on the left hand of the
decomposing chamber, for the exit of the gas, and through this pipe the gas is
conveyed into the hydraulic main or other receiver. k, k, are two openings, shewn
by dots in the lower parts of the decomposing chamber, fitted with iron doors,
which must be kept closed air-tight by luting during the process of decom-
position. These openings are for the purpose of withdrawing any portion of
the coak. The spaces at the bottom parts of the decomposing chamber into
which the pipes f, i, and the openings e, e, enter are kept clear from coak by
bars made of retort earth, or any material that will resist the action of the
fire; and these spaces are to be kept clear, in order that the steam may have
7

page_text: a free
passage into the bottom part of the decomposing chamber on one side,
and the gas a free passage out of the decomposing chamber on the other side.
The fireplace and decomposing, chamber may be made of any material that
will resist the action of fire and remain air-tight; and the bars at the bottom
of the fireplace are to be considered as being, supplied by fire-bricks laid
crossways at about two inches apart. "The decomposing chamber, when in
operation, is supposed to be always kept full of ignited coak or other carbona-
ceous matter within the space from the bars at bottom to about the height
represented in the Drawing; and the coak, requisite to keep it in that state is
supplied by the coal, which is introduced into the decomposing chamber
through the door h, as the process of carbonization goes on. By placing the
furnace or fireplace within the area of the decomposing chamber, little heat is
lost, and the chamber being thereby divided into two parts, the steam which
passes in at the opening f is caused to circulate through the ignited coak to
the top of the chamber, where the results proceeding from this part of tho
process meet and mingle with the volatile results proceeding from the decom-
position of the coals or other material under distillation, and together pass
down through the ignited coak on the other side of the chamber, meeting in
their passage with the steam or with the nascent results from the decom-
position of the steam admitted, at g. The solution of the coak will always be
in proportion to the quantity of steam passed through it; and the quantity of
steam applied must therefore be regulated by the greater or less extent of
solution intended. If it be not intended completely to dissolve the coak,
then, as the conk accumulates, a portion of it must be withdrawn from time
to time at the bottom of the decomposing chamber through the apertures k, k.
The process of the combustion of the fuel in the fireplace or furnace goes on
thus: The fuel is supplied at the top of the fire through the door a; the
air requisite to the combustion of the fuel is admitted into the fireplace above
the fuel at the opening 6; and the entrance into the flues is from the bottom
of the fireplace underneath the grating. Supposing, then, the doors a,c, and d
to be closed, the smoke and other volatile results proceeding from the
combustion of the 'fuel are forced by the current of air entering by the
aperture 6 through the whole body of ignited matter composing the fire. By
this apparatus coals, and also, tar and oil, may be decomposed at the same
time. The tar or oil must be admitted into the decomposing chamber by
means of tubes (made of retort earth) passing through the top of the chamber
on the right hand-side. of the fireplace; and the admission of these materials
must be regulated by stopcocks, and never be in greater quantities than will
become decomposed by circulating through the ignited coak, and without

page_text: reaching the bottom. The tar and oil will meet in their passage through tho
ignited coak with the steam or the nascent results from the decomposition of
the steam admitted at f, and being themselves thereby decomposed, will rise
to the top of the chamber in the state of gas. The steam of water may be
obtained by affixing thin cast-iron boilers at the back of the flues, or in any
other convenient situation or manner, and the pipes which convey the
steam must be provided with stopcocks to regulate their supply. It is
also recommended that the coals, before they are submitted to the process
of decomposition, should be broken into pieces not excceding the size of
walnuts, and that the charges should take place from time to time as the
coals get into a state of red hot ignition, in strata not exceeding an inch and
half in thickness.
The apparatus I have now described will explain the objects of this
Patent, and shew the means by which my process may be carried into
effect; but as the principles of it may be variously extended and modified,
as the shape and dimensions of it may be altered without injury to my
process, and as the furnace or fireplace and the interior sides or surfaces
between the flues and furnace (which are the parts of the apparatus most to
be attended to) may be construct 1 in any manner and of any material that
will resist the action of the fir and remain air-tight, I do not claim this
apparatus, but such parts of it only as are hereafter particularized. Such an
apparatus, moreover, is not only available in the manner explained by the
Drawing, but may be resorted to on a principle of economy where retorts are
used. In such case the retorts would bo bedded in the ignited coak which
occupies the sides and top of the fireplace, and by keeping all the openings
into the chamber closed, so as to prevent any air or steam having access to the
coak, the coak may be kept up to any degree of ignition without being consumed.
I do therefore declare that my Invention of Certain Improvements in the
Production or Manufacture of Gas consists,—
First, in the application or employment of the decomposition of water under
the process of passing steam through ignited coak or other carbonaceous
matter as an auxiliary in the production or manufacture of inflammable gas
from coals, peat, oil, tar, or other combustible substance.
Secondly, in causing the volatile results which proceed from the decompo-
sition of water, or from the decomposition of coals, peat, oil, tar, or other
combustible matters in their nascent state, or in the state in which they rise,
and before they undergo any process of cooling, to pass through ignited coak
or other carbonaceous matter, and this I claim as an auxiliary process in
the production or manufacture of inflammable gas from such materials.

page_text: Thirdly, in that particular contrivance or any other construction of apparatus
which provides for the coals being delivered for decomposition into the upper
part of the decomposing chamber, whilst the coak resulting therefrom is
withdrawn at the bottom part of the decomposing chamber from time to time
as it becomes necessary to make room at top for a fresh supply of coals.
Fourthly, in that particular contrivance, or any other construction of the
furnace and flues, which provides for the admission of the air. required for the
combustion of the fuel into the upper part of the furnace at or above the top
of the fuel, whilst the entrances into the flues are at the bottom part of the
furnace underneath the grating on which the fuel rests, by which arrangement
the smoke is caused to pass through the whole body of the fire before it can
get vent.
Fifthly, in that particular contrivance, or any other construction of the
apparatus, which places the furnace within the area of the decomposing
chamber, by which arrangement the greater part, if not the whole, of the heat
radiated from the sides of the furnace becomes available.
In witness whereof, I, the said John Holt Ibbetson, have hereunto
set my hand and seal, this Fifteenth day of November, in the year
of our Lord One thousand eight hundred and twenty-four.