IMPROVEMENTS IN THE MANUFACTURE OF ILLUMINATING GAS, AND IN THE PROVISIONAL SPECIFICATION: IN THE APPARATUS EMPLOYED THEREFOR
Year: 1874

page_text: LETTERS PATENT to James Keith, of Arbroath, in the County of
Forfar, North Britain, Gas and Water Engineer, for the Invention
of "IMPROVEMENTS IN THE MANUFACTURE OF ILLUMINATING GAS, AND IN THE
PROVISIONAL SPECIFICATION left by the said James Keith at tho
Office of the Commissioners of Patents, with his Petition, on the
27th March 1874.
•
I, JAMES. KEITH, of Arbroath, in the County of Forfar, North Britain,.
Gas and Water Engineer, do hereby declare the nature of the said.
Invention for "IMPROVEMENTS IN THE MANUFACTURE OF ILLUMINATING GAS, AND:
IN THE APPARATUS EMPLOYED THEREFOR," to be as follows, that is to say:-
This Invention relates to the manufacture of illuminating gas from
crude mineral oils, such as shale, American petroleum, or other similar
oils, whereby the gas is more thoroughly extracted from such oils than
hitherto.

page_text: The apparatus employed in carrying out this invention consists of an
improved arrangement of furnace, retort, "retort setting," and "washer,"
constructed and connected as herein-after described.
The furnace is of circular form, constructed of brickwork and fire-clay,
and is provided with a heavy circular metal grate and water pan of
brick built into the masonry beneath, and the fuel for the furnace is fed
into it by means of a slanting shaft entering the furnace at the bottom
side of the fire instead of at the top, in order to prevent the ingress of
cold air and consequent cooling of the retort or lining, as by this
arrangement of the feeding shaft any air getting in while the furnace
door is open has to pass upwards through the whole body of the fire
before it reaches the "retort setting," by which time it has become
sufficiently heated or burned in its passage through the fire..
The retort is made of metal of an equal thickness throughout, and is
flat bottomed, with circular or rounded sides and top, its outline being
in the form of an inverted bowl. The retort may also be constructed if
desired of fire-clay. It has a perforated partition in the centre dividing
it into an upper and lower division, both of which may when desired be
filled with coke or charcoal to give greater heating and distilling surface.
Two slanting shafts are cast one on each side of the retort, one sloping
into the lower division and the other from off the upper division.
When the retort is properly heated the oil is run in in a thin continuous
stream from a contiguous metal cistern through a "pipe trap" into the
lower shaft, and passes off in the form of gas through the upper shaft,
from which it drops through a pipe into the “"washer," from whence it
may be passed direct by suitable connections into the gas holder without
purification; or if desired for greater purity it may be passed through
an intermediate vessel of any desired form containing a layer of coke or
charcoal for the purpose of clarifying it. This retort can very casily be
cleaned, being provided with suitable doors, clamps, and scrows fixed on
the extremities of the slanting branches or shafts before referred to;
doors are also arranged round the "setting" of the retort to enable the
attendant to watch the heating operation. The retort being itself flat
bottomed rests upon an arch with flat roof, thus ensuring great durability
as in no part is the heat of the furnace allowed to impinge directly upon
the retort.
.

page_text: flow and discharge pipe, and is also fitted with a "cleaning-out door "
and plugs on top. The connections or pipes between the retort and
washer are fixed and pass from the retort directly through the top of
the washer, no "lutings" or movable connections being required.
The retort, furnace, and "setting" are enclosed in a metal casing, and
are surmounted or covered with a metal top plate, through which the
smoke pipe passes to the chimney or other exit. This arrangement of
apparatus is peculiarly adapted for manufacturing gas on board ship,
and when so used the only alteration necessary is the application of a
swinging instead of a fixed "washer."
It will be obvious that when desired a series of the different apparatus
herein described may be arranged side by side where increased pro
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Keith in the Great Scal Patent Office on
the 25th September 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
KEITH, of Arbroath, in the County of Forfar, North Britain, Gas and
Water Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of March, in tho
year of our Lord One thousand eight hundred and seventy-four, in the
thirty-seventh year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said James Keith, Her special
licence that I, the said James Keith, my executors, administrators,
and assigns, or such others as I, the said James Keith, 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 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 THE MANU-
FACTURE OF ILLUMINATING GAS, AND IN THE APPARATUS EMPLOYED THEREFOR,” upon
'
.

page_text: L
Keith's Improvements in the Manufacture of Gas.
the condition (amongst others) that I, the said James Keith, 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 5
Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said James Keith, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the 10
following statement in writing, reference being had to the accompanying
Sheet of Drawings and to the letters and figures marked thereon, that
is to say:-
-
My said Invention relates to the manufacture of illuminating gas
from crude mineral oils, such as shale, American petroleum, or other 15
similar oils by means of certain new or improved constructions of
apparatus, whereby the gas is more thoroughly extracted from such oils
than hitherto.
And in order that the nature and mode of performing my said Inven.
tion may be properly understood, I now procced to describe the several 20
Figures on the Sheet of Drawings which I have hereunto appended for
that purpose; the same letters of reference indicating the same parts in
all the Figures where seen.
0
The apparatus employed in carrying out the said Invention consists of
a new or improved construction, arrangement, and combination of 25
furnace, retort, retort setting, and washer, all as herein-after more
particularly described.
Figures 1 and 2 are respectively a longitudinal vertical section, and a
plan of one construction and arrangement of the parts of my new or
improved apparatus complete for producing or distilling, and "washing" 30
or cleaning gas from the said crude mineral oils for illuminating purposes,
all illustrative of and in accordance with the nature and objects of my
said Invention.
Figures 3 and 4 are respectively a right and a left hand side elevation
of the oil distilling or gas producing furnace and retort shown in and at gå
right angles to Figures 1 and 2; while Figures 5 and 6 are respectively.
°

page_text: a horizontal and a transverse vertical section of the furnace, part taken
on the lines 1-1, and 2-2, in and corresponding to Figures 2
and 3, to show the construction of the arch I, and flat circular fire-brick
part I above the furnace H for the retort A to rest on, and the
openings H¹ in the same for the flame and heated products of combustion
to pass up through.
The furnace H is of a circular form constructed of brickwork s and
fire-clay, and is provided with a heavy circular metal grate J, and water
pan or recess of brick K built into the masonry beneath which keeps the
ash-pit cool, and prevents the fire-grate or bars from being burned,
shown at Figures 1, 3, and 6; the furnace H being surmounted by a
cross brick arch I with circular flat centre I' carrying the retort resting
on it, and having openings H through or between the arches for tho
heated products of combustion to pass up into the annular space or
chamber R round the retort A. The fuel for the furnace is fed into it
by means of the slanting shaft p entering the furnace at the bottom side
of the fire, as shown in section Figure 6, instead of at the top, in order to
prevent the ingress of cold air and consequent cooling of the retort or
lining; as by this arrangement of the feeding shaft any air getting in
while the furnace door o is open has to pass upwards through the whole
body of the fire before it reaches the retort setting, by which time it has
become either sufficiently heated or burned in its passage through the
fire to assist combustion.
The retort A is preferably made of cast iron, as shown (but it may be
made of other metal, or of fire-clay or other suitable material), of an
equal thickness throughout, to provide for the contraction and expansion
of metal, and is flat bottomed with circular or rounded sides and top,
its outline being in the form of an inverted bowl. The retort A. may
have a horizontal perforated partition in the centre, dividing it into an
upper and lower division either or both of which may when desired be filled
with coke or charcoal to give greater heating and distilling surface. Or
otherwise and by preference the retort A may have a flue or pipe
division carried down through its centre, by which the flame and smoke
pass directly through the centre of the retort, as shown at C in
Figures 1 and 2, thus giving a double heating surface, that is, a heating
surface inside as well as outside of the retort. This flue or pipe arrange-
ment through the centre of the retort divides it, as it were, into an
upper and lower annular space or division, both of which when desired

page_text: may be filled with coke or charcoal to give greater heating and distilling
surface. Two slanting shafts or door pipes are cast one on each side of
the retort, one marked B sloping into the lower part or division, and the
other D from off the upper part of the said annular internal distilling
Брасс.
When the retort A is properly heated the oil which is contained in
the metal cistern i is run in by a brass valvej to the filler k, and through
the syphon trap pipe into the mouth of the retort shaft B at L, and
passes off around the hot flue division C in the form of gas through the
upper shaft D into the upright pipe P, where the gas gets "fixed" and
partly condensed, after which it passes along the pipe V, and finally
enters the washer Z at X, where any tarry matter held in solution is
washed out of it. The gas now passes off thoroughly pure and cool into
the gas holder direct by the pipe t, shown in Figure 2. This oil gas
requires no purification, but if desired it may be passed through an
.intermediate vessel before entering the gas holder containing a layer of
coke or charcoal for the purpose of clarifying the gas still more.
In making gas from the said mineral oils with this retort A no
charging or drawing in the ordinary sense is required, there being little
or no residue, but at considerable intervals after making the gas the retort
can very easily. be cleaned out through the doors M and O provided for
that purpose at the extremity of each shaft B and D; and improved
movable clamps and screws g and are also fixed on the mouth-
'pieces B' and D' of the slanting branches or shafts B and D for properly
fastening the doors M. and O hung on pins in front, and the joints of
which are made gas-tight by luting with a mixture of fire-clay and salt,
or other cement suitable for that purpose.
Doors n, n, are also arranged
in the settings or flue R round the retort to enable the attendant to
watch and regulate the heating operation.
The retort A being itself flat bottomed rests upon an arch I with flat ¿
roof I', and shown in plan and sections, Figures 1, 5, and 6, the pieces
of fire-brick marked Q fitting into spaces of the arch I, and thoroughly
protect the bottom of the retort A. This mode of setting ensures great
durability, as in no part is the heat of the furnace allowed to impinge
directly upon the retort, so that its bottom cannot get burned or out of 3
shape, and the arched part of the heating chamber R round it rever-
berates the flame or heat back on to the upper surface of the retort.
:

page_text: The washer Z is of a circular or cylindrical. form with flat top Z' and
bottom Z, and is composed of metal and provided with both an overflow
pipe a and discharge pipe b. and cap.,. and is fitted with a cleaning out
door and plugs a in pipe a. A cooler.c is fixed on the top of the
washer around the pipe V, and is kept full of water up to the level line d
and top of the overflow pipe Y, which acts as a filler to pour or run in
cold water occasionally into the washer Z, the lower end of thic pipe Y
dipping down under the level of the water line e in the washer Z.
The connections or pipes P and V between the retort. A and washer Z
are fixtures, and made extra large to prevent chokage, and pass from
the top of the shaft D directly through the top of the washer Z, 'to
which the pipe V, X, is fixed by the flange forming the bottom of the
cooler c, no lutings or movable joints or connections being required.
These pipes or connections are furnished with movable doors and
clamps U and W for cleaning out purposes.
}
The retort, furnace, and setting are enclosed in a metal casing v, and
are surrounded or covered with a metal top plate. N. The smoke pipe
or chimney T is fitted by a spigot or metal connection at F of the branch
or mouth-piece E, the connection of the retort flue with this metal
branch E being at C³, and is formed inside the fire-brick lining 8. A
hollow cylindrical damper S is fitted inside the branch connection E,
like the key of a cock, the flame and smoke as it were coming up the
inside of the key, so that by simply turning the handle S', fitted on the
outside or end of the damper S, the draft is either shut off or put on as
required, giving great power of controlling this; and, as a consequence,
the regulation of the heat of the retort. These furnaces H will burn
coke, coal, charcoal, or wood equally well as fuel for heating the retorts.
This combined arrangement of apparatus is peculiarly adapted for the
manufacture of gas on board ship; and when so used the only alteration
required being the hanging of the outer vessel or case of the washer
containing the water on a set of jimbles in the same manner as a ship's
compass or lamp, so that the water would always maintain or keep the
same level above the lower end of the dip pipe V, X, notwithstanding
the rolling of the ship.
For transportation, or other special purposes, these gas producers can
be made, built, and bolted together with tie rods completely self-con-

page_text: necessary or desirable; and it will be obvious that when desired a series
of the different apparatus, herein-before described, may be arranged side
-by side when increased production of gas is required.
Although the retort A with its slanting shafts B and D and flue
division C have been more particularly described for the production of
illuminating gas from crude mineral oils, it is to be understood, and will
be apparent to the practical gas engineer, that it is equally applicable
for the production of gas from coal, shale, or other bituminous sub-
stances with slight modifications to admit of the charging of such
.material, and the withdrawal of the coke, ash, or other residues, in which
case the retorts may be made of various sizes to suit the particular
mineral or material being distilled in them.
Having now described the nature of my said Invention, and the
manner in which the same is or may be used or practically carried into
effect, I would observe in conclusion that what I consider novel and
original, and therefore claim as the Invention secured to me by the
herein-before in part recited Letters Patent is,—
11
First. The production of illuminating gas from or by the distillation
of crude mineral oils, either for use on land or on board ship, and in the
apparatus (or furnace, retort, retort setting, and gas cleaner or washer
'combined) of the construction and arrangement, all substantially in the
new or improved manner herein described and shown in the accom-
panying Drawings, or any mere modification thereof.
Second. The construction and use of furnaces and fittings for the
heating of retorts for producing illuminating gas from crude mineral
oils, all substantially as herein-before described and shown in the accom.
panying Drawings, or any merè modification thereof.
Third. The construction and use of retorts with domed upper and flat
bottomed ends, and either with a perforated partition or a central heating
division flue for the production of illuminating gas from crude mineral
oils, all substantially as herein-before described and shown in the accom-
panying Drawings, or any mere modification thereof.
Fourth. The construction and use of a washer or cleaner for illumi-
nating gas produced from crude mineral oils, substantially as herein.
+

page_text: before described and shown in the accompanying Drawings, or any mero
modification thereof.
In witness whercof, I, the said James Keith, have hereunto set
my hand and seal, this Eighteenth day of September, in the year
of our Lord One thousand eight hundred and seventy-four.
JAMES KEITH. (L.S.)