IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF GAS
Year: 1853

page_text: LETTERS PATENT to Alexander Angus Croll, of Howrah House,
East India Road, one of the Sheriff's of London and Middlesex,
for the Invention of "IMPROVEMENTS IN APPARATUS USED IN THE
MANUFACTURE OF GAS."
Scaled the 28th December 1853, and dated the 7th July 1858.
PROVISIONAL SPECIFICATION left by the said Alexander Angus
Croll at the Office of the Commissioners of Patents, with his
Petition, on the 7th July 1853.
I, ALEXANDER ANGUS CROLL, of Hourah House, East India Road,
one of the Sheriff's of London and Middlesex, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN APPARATUS USED IN
THE MANUFACTURE OF GAS" to be as follows:-
The improvements relate, first, to modes of arranging the retorts and
the retort chambers, by causing the heat from the furnace to pass
directly into a chamber containing clay retorts, and thence through
openings into a side chamber or side chambers divided vertically by
open shelves on which other retorts rest, and through which the heated
particles from the first chamber pass down amongst such other retorts

page_text: to a lowermost set of retorts supplied by heat only as it passes off from
the others. The retorts in these side chambers may be of iron or thin
fire clay, or the first chambers containing the clay retorts, and into
which the heat first enters from the furnace used, may be on each side
of a central chamber divided vertically into open shelves, and con-
taining iron or thin clay retorts, heated by the heated particles passing
off from the first chambers.
Secondly, to setting the furnace high up in retort chambers or ovens,
when the heat first acts upon ordinary clay retorts in the usual manner,
and thence descends to let other clay rotorts on each side and below
the level of the furnace, and which retorts I prefer to be made thinner
than those heated by the direct heat. Thence the heat passes to other
iron or thin clay retorts placed immediately under the furnace.
Thirdly, to setting iron retorts to be heated-by direct heat, so that
the heat may pass freely and rapidly away by channels to another
chamber below containing other retorts.
Fourthly, to the use of balls or other weighted valves to the dif-
ferent passages from the retorts to the main, by which, whilst a fresh
charge is being placed in any retort, the passage from such retort to
the main may for the time be closed, in substitution of the hydraulic
main.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alexander Angus Croll in the Great Seal
Patent Office, on the 7th January 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,
ALEXANDER ANGUS CROLL, of Howrah House, East India Road, one of
the Sheriff's of London and Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Seventh day of July, in the year of
our Lord One thousand eight hundred and fifty-three, in the seven-
teenth year of Fler reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Alexander Angus Croll,. Her special
licence that T, the said Alexander Angus Croll, my executors, adminis-

page_text: trators, and assigns, or such others as I, the said Alexander Angus
Croll, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter
luring the term therein expressed, should and lawfully might make,
use, excrcise, and vend, within the United Kingdom of Great Britain
and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN APPARATUS USED IN THE MANUFACTURE OF GAS," upon
the condition (amongst others) that I, the said Alexander Angus Croll,
by an instrument in writing under my hand and seal, should particu-
larly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the sauc 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 Alexander Angus Croll, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascer-
tained in and by the following statement thereof (that is to say):
My improvements relate, first, to modes of arranging the retorts and
the retort chambers, by causing the heat from the furnace used to pass
directly into a chamber containing clay retorts, and thence through
openings in the side walls of such chamber into a side chamber or side
chambers divided vertically by open shelves on which other retorts rest,
and through the spaces between which shelves the heat passes to the
various retorts in such side chambers.
Secondly, my Invention relates to setting the furnace used to heat
retorts employed in generating gas high up in the retort chambers or
ovens, by which other retorts may be placed immediately under such
furnace, the heat first acting upon ordinary clay retorts in the usual
manner; thence descending to heat other clay retorts on each side and
below the level of such furnace, and thence to iron or thin clay retorts
placed immediately under the furnace.
Thirdly, my Invention relates to a mode of setting retorts in chambers
or ovens so that the heat first acts direct upon iron retorts in one
chamber or oven, & then passes freely and rapidly away by channels
to another chamber below containing other retorts.

page_text: And, fourthly, my Invention relates to the use of balls or other
weighted valves to the different passages from the retorts to the main,
by which, whilst a fresh charge is being placed in any retort, the passage
from such retort to the main may for the time be closed, in substitution
of water sealing or "the hydraulic main."
But that the improvements may be fully understood I will proceed
to explain the means pursued by me, reference being had to the
Drawings annexed.
Figure 1, shows a front view, partly in section, of an arrangement
of apparatus according to the first part of the Invention. Figure 2,
is a longitudinal section of the same taken through the centre at 1, 1;
and Figure 3, is a similar section taken through one of the side cham-
bers on the line 2, 2. The retorts shown in these chambers are of
considerable length, and they have mouth pieces for feeding at both
ends thereof. I would, however, state that although I have in cach
case shown my improvements with the use of retorts of considerable
length, having mouth pieces at each end thereof, the retort chambers
being adapted to such length of retorts, I do not confine my improved
arrangements of retort chambers to when using such retorts, as the
several improvements are applicable when short retorts, or retorts of
the ordinary length having mouth pieces at one end only, are used.
The chamber A, is divided into two by a partition wall A', by which it
becomes in eflect two distinct chambers or compartments placed back
to back. Each central chamber or compartment A, is heated by a
furnace a, place at the lower part thereof. b, b, are eight retorts of
fire clay (but this number may be varied), amongst and around which
the heat from fires in the furnaces a, circulates. The retorts b, b, are
supported in the direction of their length by walls c, c, c, through cach
of which are formed passages c', c', in order that the heat may be com-
municated to the different parts of the retorts. The partition wall A',
in the oven or chamber A, whilst it aids to support the centre of the
retorts b, it also prevents heat from one furnace a, communicating with

page_text: the other furnace placed in the other compartment A, of the same
chamber.
The heat from cach chamber or compartment A, thence passes
through openings e, e, to chambers B, B, one on each side of a chamber
or compartment A. In these chambers B, are formed arches f, which
with the tiles f, form shelves upon which rest the retorts g, which may
be formed of iron, or they may be thin clay retorts, and by the retorts
being thus supported upon shelves which are independent of each other
offers great facility for removal and replacement of the retorts when
any one or more of them becomes unfit for use without interfering with
the remaining retorts.
The heat having circulated around the retorts in the chambers B.
passes away by the passages h, h, to passages i, formed under each of
the lowermost retorts, and thence by the openings j, to the flue k. 1, are
tiles which may be slided more or less over the openings into the main
flue by means of rods passed through openings m. When using
arrangements of retorts as shown I employ a moveable stage, which
may be used to facilitate the clearing and feeding of the upper rows of
retorts, and moved out of the way when clearing and feeding the lower
rows of retorts. An end view of a stage which I employ for this pur-
pose is shown at C, C, in connection with Figure 3; and Figure 4, is
a plan of the stage. The frame of the stage C, is supported upon
wheels D, and E, which run upon the rails D', and E¹, to enable the
attendants readily to shift it from one part of the house to the other.
But when a fewer number or fewer rows of retorts are used in the
chambers A, or B, the use of a stage will be unnecessary. When
using short retorts with one end permanently closed in settings accord-
ing to my improvements, I prefer that they be so set that the open
ends or mouth pieces with the ascending pipes of the upper rows be on
one side of the settings, and the open ends or mouth pieces with the
ascending pipes of the lower rows be on the opposite side of the settings,
with a raised stage on one side to facilitate access to the mouths of the
upper retorts. The row of ascending pipes at each side may open
into the same or to separate mains.
Another arrangement according to this part of the Invention is

page_text: shown by Figure 5. In this case there are two chambers A, to each
chamber B, and the heat, after acting upon the retorts in the chambers
A, passes through openings e, e, into the centre chamber B. But as the
mode of arranging and supporting the retorts in the chambers A, B,
and the mode of conducting away the heat from the chamber B, arc
similar to what has been above described in respect of Figures 1, 2,
and 3, I have thought it unnecessary to shew other views of this
arrangement, and have simply applied similar letters to each of the like
parts. Figure 6, shows a cross section, and Figure 7, a longitudinal
section of a setting according to the second part of my Invention. In
this case the furnaces a, are set high up in each compartment of the
chamber or oven, and the heat first acts upon the clay retorts b, b, b, b,
thence upon the retorts 61, 61, 62, 62, 62, b², arranged on each side of the
furnace, and thence upon the iron or thin clay retorts 6, placed imme-
mediately under the furnaces a. i, i, are passages under the lower
retort to the main flues k. c, c, are supporting walls for the retorts,
with openings c', for the passage of the heat, and openings c², that the
walls c, may not be in contact with the retorts b³. The furnaces a, are
supported on piers o, o, between which there are openings p, p, for the
free passage of heat to the retorts 6, the heat thence passes through
openings h, h, to the passages i, under the lower retort b", thence by the
openings, to the main flues k, ke. And it is this arrangement and
mode of working which constitutes the peculiarity of this part of the
Invention. Figure 8, shows a cross section; and Figure 9, a longitu-
dinal section of a setting according to the third part of my Invention.
The heat from the furnaces a, in this case, acts directly upon the iron
retorts m, n, in the chamber A, and thence it passes by the channels
9, 9, into the separate chamber B, containing iron or thin clay retorts
s, s', beneath the chamber A. The heat thence passes by the
passages i,
formed under the lower of the retorts s, s¹, in the chamber B, to the
main flues.
The retorts n, n, are supported upon shelves n¹, n¹, formed of fire
tile. ff are arches for supporting the retorts 8, 8. And it is this
arrangement and mode of working whereby the heat, after acting upon
iron retorts in one chamber, passes away to heat other iron or thin clay

page_text: retorts in another chamber below, which constitutes the peculiarity of
this part of the Invention.
I will now describe the fourth part of my Invention. Heretofore in
the manufacture of gas it has been usual to employ what are called
"hydraulic mains," which are partly filled with water, to receive and
thus seal the ends of the pipes or channels which conduct the gas
generated from the separate retorts, to prevent the return of the gas
produced through any of such passages again to the retorts which, for
the time, are being recharged. But water thus employed is objection-
able, inasmuch as it increases the pressure on the retorts. I therefore
employ a separate ball or valve to each pipe from the retorts capable
of closing the passage from the retort to the main when desired. The
arrangement which I adopt is shown applied at Figure 2. q, is the
weighted valve which is supported by a small rod q', passing through
a stuffing box 1, in the pipe leading from each end of a retort. To the
small rod q, is attached the band or chains, which passes over the
roller, to lift the valve and open the passage to the main when
working. When a fresh charge is being applied the valve q, is allowed
to fall and close the passage from such retort to the main. I have only
shown the arrangement of valve applied to retorts such as used by me,
and open at both ends, but it will be evident that the same is equally
applicable when the gas generated passes away from one end only.
Having thus described the nature of my said Invention, I would
have it understood that what I claim is, the modes of arranging and
combining apparatus used in the manufacture of gas as herein ex-
plained.
In witness whereof, 1, the said Alexander Angus Croll, have
hereunto set my hand and scal, this Seventh day of January,
in the year of our Lord One thousand eight hundred and
...
A. ANGUS CROLL. (L.S.)
Witness, WILLIAM BROOKES,
73, Chancery Lane.