LIGHTING AND EXTINGUISHING STREET AND OTHER GAS LAMPS AUTOMATICALLY
Year: 1885

page_text: We, JOSEPH JOHN BUTCHER, of 4 St Nicholas' Buildings, and JOHANN HEINRICH
WÜSTER, of 6 Blandford Street, both in the City and County of Newcastle-on-
Tyne, Engineers, do hereby declare the nature of our invention for LIGHTING
AND EXTINGUISHING STREET AND OTHER GAS LAMPS AUTOMATICALLY to be as
follows
Calend
We employ a small permanent flame (called sometimes a bye pass burner or
master light) beside the larger burner which has to be lighted, this small flame
drawing its gas from behind the apparatus by means of which the gas is turned on
and shutt off
This apparatus may be constructed of two concentric cylinders or tubes both
open at the bottom, but joined together by a cover which is common to them
Through the centre of this cover and concentric with the cylinders a small third
tube passes and projects up through the cover plate which extends inwards so as
to join this tube with the two larger concentric rings This latter tube is open
both at the top and at the bottom Thus the three tubes form three concentric rings
(preferably of glass), all open at the bottom but united at the top by a disc or top
plate, and the small tube is open inside through its whole length We usually
make the bottom edges of the inner and outer tubes upon the same level, but make
the other tube (which is of larger diameter than the central tube, but of smaller
diameter than the outside tube) shorter, so that its bottom edge does not project so
far downward. The bottom edges of these tubes all dip into mercury (or other
suitable fluid), but while in the action of the apparatus the bottom edges of the
inner and outer tubes always move within and are thus sealed by the mercury, so
that no gas can pass beneath them, the bottom edge of the other shorter tube, or
middle concentric ring, completely emerges from the mercury when it is lifted by
the pressure of the gas, and thus makes open communication between the annular
space which lies between the inner tube and the shorter middle tube, and between
the latter and the outer tube Round the top of the central tube above the cover
plate we may arrange a cup for shot or other suitable weights
The bottom edges of the tubes dip into mercury, which is contained in three
corresponding annular grooves or ditches in the casing (the main portion of which
is preferably of cast iron), which are united by a radial groove or ditch, so as to

page_text: allow the mercury to flow freely from one to the others, and maintain constantly
the same level thoughout The grooves are made deeper than is required for the
mercury so as to prevent the latter, if jerked, from splashing over the surfaces of
the rings of 11 on which divide them The outer ring of mercury is bounded by the
side of the casing, which rises higher than the dividing rings so as to receive the
cover plate which encloses the apparatus
We prefer to so construct the apparatus that the gas is both supplied to, and
ultimately emerges from, it centrally, or along its (vertical) axis
For this purpose
we form a central boss upon the underside of the casing, which is screwed so as to
receive the gas cock or gas pipe which supplies the gas to it From the space above
the gas cock or pipe one, two, or more holes, or channels, which act as gas pipes,
lead to the space between two of the hanging tubes which dip in the mercury
In cases in which a considerable difference exists between the lighting and
extinguishing pressures, we prefer the gas to be first supplied to the space between
the inner tube and the middle shorter tube, as this enables the areas successively
exposed to be best adjusted to one another, while preserving a convenient distance,
measured radially, between each pair of the tubes (that is between the inner
and the middle, and between the middle and the outer) In cases in which there
18 but a slight difference between the igniting and extinguishing pressures however,
the gas may be first fed between the middle and the outer tubes We will proceed
to describe the apparatus as constructed upon the former method
From the space between the middle and outer tubes a pipe (or pipes) leads
downwards into the metal casing, then bends horizontally and takes a radial
direction, and then bends upwards and takes a vertical direction, this latter portion
of the pipe being in the centre of the apparatus, and first forming the inner wall
of the central groove or ditch containing the mercury, then passing upwards right
through the inner of the three concentric hanging tubes, which work within the
mercury (the latter tube being an easy working fit over the former, which thus acts
as a guide to the working portion of the apparatus) and then passing upwards
through a hole in the cover plate, above which it is screwed to receive the gas
governor pipe or coupling, which is in connection with the main gas burner oi
burners. This latter may thus be made to act as a nut which retains the cover
plate firmly in its position
We may effect this purpose by bending an iron gas pipe into the form described,
and then casting the bottom portion of this pipe into the metal casing, which thus
holds it down firmly
When, in the action of the apparatus, the gas is turned on to the main gas burner,
a distinct diminution of pressure within the apparatus is the result, so that, unless
a considerable extra area is exposed to the lifting pressure of the gas, the shorter
tube would fall back to the surface of the mercury, and bubbling and flickering of
the light would result. This defect is however effectually checked by exposing a
large new area to the lifting power of the gas, so as to compensate for the
diminished pressure due to the sudden outflow
As it is often the practice in towns lit with gas to carry a low pressure during
the day, and gradually increase it as the shop and household jets are being lighted,
until it reaches a maximum when the street lamps are required, this maximum
pressure may be required to be the lighting pressure, and this end may be attained
by making the lifting area first exposed to the pressure of the gas such that it will
allow the apparatus to lift and turn on the gas only when the town pressure
reaches its maximum As however the shop and household lights are put out late
in the evening, the pressure is frequently turned down low during the rest of the
night and dark hours of the morning, so that to keep the street lamps lighted the
second area exposed to the gaseous pressure must be of such size that it, together
with the first, will sustain the apparatus open while the pressure is low
When
however the pressure is still further reduced the bottom edge of the short tube
touches the mercury, and an instant diminution of gaseous pressure taking place in
the second area, sudden olosure and shutting off of the gas results.

page_text: The pipe leading to the small flame may be screwed into the boss at the
bottom of the apparatus so as to be fed by the gas before it enters the apparatus
for turning it on and off to the main jet As this flame has to burn constantly,
and during the day when no light is required, it is of great importance that it
should be as small, and burn as little gas, as practicable Such small flames
require special protection from draughts within the lamp We may effect this
purpose by means of surrounding the small flame by one, two, or more small cones
formed of thin sheet metal or other suitable material These cones are placed
base downwards, and the small flame is placed axially with regard to them. The
apices of the cones are removed so that they are open at the top, where the holes
are just sufficiently large to allow the flame to burn freely through them
The
The top aperture of the lower cone is so placed as to surround the flame just
above its base, so that, if the part of the flame which emerges from the hole is
blown out, the base of the flame will still remain lighted The base of this cone is
continued downwards as a cylinder surrounding the small gas burner, so as to
allow sufficient room for the free circulation of air required for combustion
bottom edges of this cylinder may be bent inwards and downwards so as to form
a very short inverted cone (or rather frustum of a cone) the aperture in the
bottom of which is sufficiently large to admit the air for combustion quite freely.
Placed below this conical termination to the cylinder, and at a sufficient distance
from it to allow of ample air way, is a guard attached to the gas pipe so as to
prevent any draught from entering vertically into the aperture in the inverted
cone, and this guard may have its edges beveled inwards and upwards If then the
arrangement is otherwise such that any draught passing the annular air way must
take a vertical direction (upwards or downwards), the edges will so deflect it as to
tend to prevent its entering the cylinder below the cone surrounding the little
flame, which will thus remain unaffected thereby
The cone surrounding the flame deflects draughts which come diagonally
downwards, so that they do not enter the aperture in which the base of the flame
is burning Another or other similar cones may be placed above this one, but
must be left open at the base instead of being continued downwards by a cylinder
This allows of the escape outwards of the deflected air currents or draughts
These cones are surrounded by, and attached to (by supports so arranged as not to
interfere with the air way), an outer cylindrical casing, which 18 curved inwards
and downwards at its lower termination below the guard upon the gas pipe to
another circular aperture for the entry of the air for combustion, and the escape
of draughts Space must be allowed between the cones and internal cylinder and
this outer casing for the free passage of any draughts which may be deflected by
the cones, or otherwise enter, into it It will be seen that this guard is so arranged
that no draughts can attack the flame except those approaching it from a direction
immediately above it, and these latter may be readily guarded against in the
construction of the gas lamps
The action of the apparatus is as follows The gas entering the apparatus from
the main during the day at low pressure constantly tends to lift the inverted cup
or valve whose edges dip into the mercury, but this valve is so weighted by shot,
or otherwise, as to resist the pressure of the gas until a higher pressure is attained
This pressure is turned on at the gas works (or elsewhere if convenient) when the
street lamps require to be lighted, and the valve then rises so that the shorter
cylinder emerges from the mercury, and the second area of the valve is exposed
to the gaseous pressure, the gas at the same time being turned on to the main gas
burner or burners, the jets from which are ignited by the small permanent flame
When this is doue the gas may be turned down to a lower pressure without closing
the mercurial valve, provided it is not diminished to the extinguishing pressure
When it is desired to extinguish the gas lamps the gas pressure is lowered still
more to this extinguishing pressure, after which it may be raised if desired to any
pressure below the lighting pressure without opening the mercurial valve,

page_text: In cases in which it is desired to light some of the gas lamps earlier than others
(as alternate lamps as it grows dusk, and the rest of the gas lamps when it
becomes still darker) we construct one set of mercurial valves so that they will
open earlier than the rest This may be done either by arranging the areas to
suit these conditions or more readily by a different weighting of the valves
A pressure governor may be conveniently combined with the apparatus described
above If a light rod is suspended from the mercurial valve over the gas inlet
port (there being in this case preferably only one such inlet port or passage), and
pisses down through the latter and is made to carry on its bottom end a valve
closing upwards, but so arranged that it does not begin to throttle the inlet
passage until after the gas is turned on to the burner by the shorter tube rising
out of the mercury, then as the mercurial valve rises higher and higher after the
second surface is exposed to the pressure, this valve gradually diminishes the inlet
opening until the outflow of the gas to the burner (or burners) so reduces the
pressure within the bell of the mercurial valve that the weight of the latter is
only just sustained by the gas. Thus the pressure in the bell will never
appreciably exceed the sustaining pressure, and as the pressure in the mains falls,
the small valve will open wider so as to keep up the pressure within the bell until
the pressure in the mains falls to the extinguishing pressure Thus a uniform low
pressure is maintained within the apparatus, and, if it is desired to reduce the
pressure still further at the burner, this may be effected by simply throttling the
passage by any ordinary device such as an adjustable screw partially closing it.

page_text: We JOSEPH JOHN BUTCHER, of 4 St Nicholas' Buildings, and JOHANN HEINRICH
WUSTER, late of 6 Blandford Street, both in the City and County of Newcastle-'
on-Tyne, Engineers (the aforesaid Johann Heinrich Wuster, being now of Ybbs,
% Donan, Nieder-Oesterreich, Austria) do hereby declare the nature of our
invention for LIGHTING AND EXTINGUISHING STREET AND OTHER GAS LAMPS
AUTOMATICALLY and in what manner the same 18 to be performed, to be
particularly described and ascertained in and by the following statement
-
We employ a small permanent flame (called sometimes a bye pass burner or
master light) beside the larger burner which has to be lighted, this small flame
drawing its gas from behind the apparatus by means of which the gas is turned on
and shut off
This apparatus may be constructed of two concentric cylinders or tubes both
open at the bottom but joined together by a cover which is common to them
Through the centre of this cover and concentric with the cylinders a small third
tube passes and projects up through the cover plate which extends inwards so as
to join this tube with the two larger concentric rings. This latter tube is open
both at the top and at the bottom-Thus the three tubes form three concentric
rings (preferably of glass) all open at the bottom but united at the top by a disc
or top plate, and the small tube is open inside through its whole length We
usually make the bottom edges of the inner and outer tubes upon the same level,
but make the other tube (which is of larger diameter than the central tube, but of
smaller diameter than the outside tube) shorter, so that its bottom edge does not
project so far downwards. The bottom edges of these tubes all dip into mercury
(or other suitable fluid), but while in the action of the apparatus the bottom edges
of the inner and outer tubes always move within and are thus sealed by the
mercury, so that no gas can pass beneath them, the bottom edge of the other
shorter tube, or middle concentric ring, completely emerges from the mercury when
it is lifted by the pressure of the gas, and thus makes open communication between
the annular space which lies between the inner tube and the shorter middle tube,
and between the latter and the outer tube Round the top of the central tube
above the cover plate we may arrange a cup for shot or other suitable weights.
The bottom edges of the tubes dip into mercury which is contained in three
concentric annular grooves or ditches in the casing (the main portion of which is
preferably of cast iron) which are united by a radial groove or ditch, so as to allow
the mercury to flow freely from one to the others, and maintain constantly the
same level throughout. The grooves are made deeper than is required for the
mercury so as to prevent the latter, if jerked, from splashing over the surface of
the rings of iron which divide them The outer ring of mercury is bounded by
the side of the casing which rises higher than the dividing rings so as to recarve
the cover plate which encloses the apparatus.
We prefer to so construct the apparatus that the gas is both supplied to, and
ultimately emerges from, it centrally,or along its (vertical) axis. For this purpose

page_text: we form a central boss upon the underside of the casing, which is screwed so as
to receive the gas cock or gas pipe which supplies the gas to it
From the space
above the gas cock or pipe one, two, or more holes, or channels, which act as gas
pipes, lead to the space between two of the hanging tubes, which dip in the
mercury In cases in which a considerable difference exists between the lighting
and extinguishing pressures, we prefer the gas to be first supplied to the space
between the inner tube and the middle shorter tube, as this enables the areas
successively exposed to be best adjusted to one another, while preserving a
convenient distance, measured radially, between each pair of the tubes (that is
between the inner and the middle, and between the middle and the outer) In cases
in which there is but a slight difference between the igniting and extinguishing
pressures however, the gas may be first fed between the middle and the outer
tubes. We will proceed to describe the apparatus as constructed upon the former
method
From the space between the middle and outer tubes a pipe (or pipes) leads
downwards into the metal casing, then bends horizontally and takes a radial
direction, and then bends upwards and takes a vertical direction, this latter portion
of the pipe being in the centre of the apparatus, and first forming the inner wall
of the central groove or ditch containing the mercury, then passing upwards right
through the inner of the three concentric hanging tubes, which work within the
mercury (the latter tube being an easy working fit over the former, which thus
acts as a guide to the working portion of the apparatus) and then passing upwards
through a hole in the cover plate, above which it is screwed to receive the gas
governor pipe or coupling, which is in connection with the main gas burner or
burners This latter may thus be made to act as a nut which retains the cover
plate firmly in its position.
We may effect this purpose by bending an iron gas pipe into the form described,
and then casting the bottom portion of this pipe into the metal casing, which thus
holds it down firmly
When, in the action of the apparatus, the gas is turned on to the main gas
burner, a distinct diminution of pressure within the apparatus is the result, so that,
unless a considerable extra area is exposed to the lifting pressure of the gas, the
shorter tube would fall back to the surface of the mercury, and bubbling and
flickering of the light would result. This defect is however effectually checked by
exposing a large new area to the lifting power of the gas, so as to compensate for
the diminished pressure due to the sudden outflow
As it is often the practice in towns lit with gas to carry a low pressure during
the day and gradually increase it as the shop and household jets are being lighted
until it reaches a maximum when the street lamps are required, this maximum
pressure may be required to be the lighting pressure, and this end may be attained
by making the lifting area, first exposed to the pressure of the gas such that it
will allow the apparatus to lift and turn on the gas only when the town pressure
reaches its maximum As however the shop and household lights are put out late
in the evening, the pressure is frequently turned down low during the rest of the
night and dark hours of the morning, so that to keep the street lamps lighted the
second area exposed to the gaseous pressure must be of such size that it, together
with the first, will sustain the apparatus open while the pressure is low
however the pressure is still further reduced, the bottom edge of the short tube
touches the mercury, and an instant diminution of gaseous pressure taking place
in the second area, sudden closure and shutting off of the gas results.
When
The pipe leading to the small flame may be screwed into the boss at the bottom
of the apparatus so as to be fed by the gas before it enters the apparatus for
turning it on and off to the main jet As this flame has to burn constantly, and
during the day when no light is required, it is of great importance that it should
be as small, and burn as little gas, as practicable Such small flames require special
protection from draughts within the lamp We may effect this purpose by means
of surrounding the small flame by one, two, or more small cones formed of thin

page_text: sheet metal or other suitable material These cones are placed base downwards,
and the small flame is placed axially with regard to them The apices of the
cones are removed so that they are open at the top, where the holes are just
sufficiently large to allow the flame to burn freely through them The top aperture
of the lower cone is so placed as to surround the flame just above its base, so that, if
the part of the flame which emerges from the hole is blown out, the base of the flame
will still remain lighted The base of this cone is continued downwards as a cylinder
surrounding the gas burner, so as to allow sufficient room for the free circulation of
air required for combustion The bottom edges of this cylinder may be bent
inwards and downwards so as to form a very short inverted cone (or rather frustum
of a cone) the aperture in the bottom of which is sufficiently large to admit the
air for combustion quite freely Placed below this conical termination to the
cylinder, and at a sufficient distance from it to allow of ample air way, is a guard
attached to the gas pipe so as to prevent any draught from entering vertically into
the aperture in the inverted cone, and this guard may have its edges bevelled
inwards and upwards. If then the arrangement is otherwise such that any draught
passing the annular air way must take a vertical direction (upwards or downwards)
the edges will so deflect it as to tend to prevent its entering the cylinder below
the cone surrounding the little flame, which will thus remain unaffected thereby.
The cone surrounding the flame deflects draughts which come diagonally down-
wards, so that they do not enter the aperture in which the base of the flame is
burning Another or other similar cones may be placed above this one, but must
be left open at the base instead of being continued downwards by a cylinder This
allows of the escape outwards of the deflected air currents or draughts These
cones are surrounded by, 'and attached to (by supports so arranged as not to
interfere with the air way), an outer cylindrical casing, which is curved inwards
and downwards at its lower termination below the guard upon the gas pipe to
another circular aperture for the entry of the air for combustion, and the escape of
draughts Space must be allowed between the cones and internal cylinder and
this outer casing for the free passage of any draughts which may be deflected by
the cones, or otherwise enter, into it. It will be seen that this guard is so arranged
that no draughts can attack the flame except those approaching it from a direction
immediately above it, and these latter may be readily guarded against in the
construction of the gas lamps
The action of the apparatus is as follows. The gas entering the apparatus from
the main during the day at low pressure constantly tends to lift the inverted cup
or valve whose edges dip into the mercury, but this valve is so weighted by shot,
or otherwise, as to resist the pressure of the gas until a higher pressure 18 attained.
This pressure is turned on at the gas works (or elsewhere if convenient) when the
street lamps require to be lighted, and the valve then rises so that the shorter
cylinder emerges from the mercury, and the second area of the valve is exposed to
the gaseous pressure, the gas at the same time being turned on to the main gas
burner or burners, the jets from which are ignited by the small permanent flame
When this is done the gas may be turned down to a lower pressure without closing
the mercurial valve, provided it is not diminished to the extinguishing pressure.
When it is desired to extinguish the gas lamps the gas pressure is lowered still
more to this extinguishing pressure, after which it may be raised if desired to any
pressure below the lighting pressure without opening the mercurial valve.
In cases in which it is desired to light some of the gas lamps earlier than others
(as alternate lamps as it grows dusk, and the rest of the gas lamps when it
becomes still darker) we construct one set of mercurial valves so that they will
open earlier than the rest This may be done either by arranging the areas to
suit these conditions, or more readily by a different weighting of the valves.
A pressure governor may be conveniently combined with the apparatus described
above. If a light rod is suspended from the mercurial valve over the gas inlet port
(there being in this case preferably only one such inlet port or passage), and passes

page_text: down through the latter and is made to carry on its bottom end a valve closing
upwards, but so arranged that it does not begin to throttle the inlet passage until
after the gas is turned on to the burner by the shorter tube rising out of the
mercury, then as the mercurial valve rises higher and higher after the second
surface is exposed to the pressure, this valve gradually diminishes the inlet opening
until the outflow of the gas to the burner (or burners) so reduces the pressure
within the bell of the mercurial valve that the weight of the latter is only just
sustained by the gas. Thus the pressure in the bell will never appreciably exceed
the sustaining pressure, and, as the pressure in the mains falls, the small valve will
open wider so as to keep up the pressure within the bell until the pressure in the
mains falls to the extinguishing pressure Thus a uniform low pressure 19 main-
tained within the apparatus, and, if it is desired to reduce the pressure still further,
at the burner, this may be effected by simply throttling the passage by any ordinary
device, such as an adjustable screw partially closing it
Figure 1 is a sectional elevation, figure 2 is a plan, and figure 3 is a sectional
plan, of the automatic valve and casing of our apparatus, figure 4 is a sectional
elevation, and figure 5 a sectional plan of the higher end of the pipe K figure 1,
figure 6 18 a side view of the apparatus complete, which is also shewn on a smaller
scale in figure 7 attached to a lamp post, figure 8 is a sectional elevation and
figure 9 is a sectional plan of the draught guard with which we surround the small
permanent flame
The boss B upon the bottom of the casing C is tapped so as to screw on to the
service pipe of the lamp post as shown in figure 7 The gas enters at A and it
ascends through the passage G into the valve D. This valve is divided internally
by the cylindrical wall M into two annular compartments E and F Of these E
may be called the lifting compartment and F the sustaining compartment The
pipe K is preferably of wrought non or steel and is cast into the casing C It
leads from F through the casing to the main burner L figure 6 M is the cover
plate of the valve Ď and the tube A passing through its centre forms the inner
wall of E N forms the outer wall of the valve and A and N extend downwards
to a lower level than M J is a cup for weighting the valve and O is the cover of
the casing C The central portion of the pipe K forms a guide upon which the
tube A and valve D work The bottom edges of a M and N dip into annular
grooves or ditches in the casing C which are shown in figures 1 and 3 These
grooves contain mercury (shown in horizontal section lines in figure 1) and are
Joined by the radial channels q figure 3 so that the mercury can flow freely from
one to the other The shorter end of K and the upper end of G rise into and
through these radial channels, M not being so deep as N and a has a shallower
groove to work into
7 18 a cap screwed or otherwise fitted upon G, and it 18 80
formed as to act as a seat against which the small pressure governing valve 6
closes when the valve D rises and carries 6 up with it The valve spindle which
carries 6 is made so long that no throttling action takes place until the edge H has
risen quite clear of the mercury
The action of D is as follows The gas enters the compartment E at all times, but
when the valve 18 in the position shewn in figure 1 the mercury seals the edge H,
and thus prevents it from entering F The cup J is weighted so that D will not
rise sufficiently to unseal H until the gas pressure has been increased to the
pressure at which it is intended that lighting should take place When this
pressure is attained H emerges from the mercury and the compartment F is
exposed to gaseous pressure so that a much increased lifting force is exerted upon
the valve which then rises rapidly until the small valve 6 approaches its seat and
so throttles the inlet as to reduce the pressure within E and F until the force
exerted will only just sustain the weight of D and its appurtenances, this reduction
of pressure taking place because of the outflow of gas to the burner L figure 6
10 is a guide pin for preventing the valve from turning and thus altering the
position of the small valve 6 with regard to the centre of the pipe G.

page_text: The reduced pressure obtainable in the bell of this form of valve being always a
little greater than within it at the moment of closure may be required to be still
further reduced for economical consumption at the gas burner As the reduced
pressure within the bell is practically uniform this may be done simply by
throttling as shewn in figures 4 and 5 K figure 4 is the top of the pipe K
figure 1, and is screwed internally to receive the plug 8 in the side of which is a
wedge shaped slot 9 By screwing this plug in and out, the aperture given by the
slot at its point of emergence from the pipe can be adjusted, and the pressure thus
throttled as required
The governor shewn in figures 1, 4 and 5 may sometimes be wholly omitted
and one of the governors now ordinarily used screwed upon the top of the pipe K
so as to form a nut to retain the cover O in place as is shown in figures 6 and 7
The pipe $ figures 1, 2, 3, and 6, screwed into the boss B conducts the gas
from A to the small flame as in figures 6 to 9 In figures 8 and 9 r is the
permanent flame surrounded by the cylindrical casing 4 coned at top and bottom
as shewn Beneath the bottom is the boss 11 which prevents the direct entry of
draughts The top is further protected by the cone 12 13 is the outer casing
through a hole in the top of which the main gas jet is ignited as shewn in figure 6
14, 14, 14, are three radial ribs to which the cones 12 and 4, and boss 11, are
firmly attached by hard solder or other suitable means
And having now particularly described and ascertained the nature of our said
invention, and in what manner the same is to be performed, we declare that what
we claim 19
(1) In an automatic gas lighting apparatus in which the gas is turned on to the
burner by means of its pressure opening a valve, the use of an additional surface
(or surfaces) which becomes exposed to the gas pressure when the valve opens, and
which is of such a size as to enable the gas to sustain the valve in its open position
while the gas pressure is reduced as such reduction is usual in practice.
(2) The prevention of fluctuations of the flame during lighting and extinguishing
by means of so constructing the apparatus that sudden opening and closure of the
valve is effected by means of a second surface, which is exposed to the pressure of
the gas upon the first opening of the valve and relieved of the pressure of the gas
on the first closure of the valve, and which is substantially larger than would be
required to cover the end of the gas outlet pipe
(3) The method of constructing the valve of an apparatus substantially similar
to that described herein of three concentric cylinders or rings united by a cover
plate substantially as hereinbefore described and illustrated in the accompanying
drawings
(4) The method of constructing an apparatus substantially similar to that
described herein, so that the gas enters at its bottom centre and emerges from it
at its top centre, substantially as herein before described and illustrated in the
accompanying drawings.
(5) The method of guiding the working parts of an apparatus substantially
similar to that described herein by means of a gas pipe passing through it
substantially as hereinbefore described and illustrated in the accompanying
drawings
(6) The method of forming the gas outlet passage in an apparatus substantially
similar to that described herein by means of casting a bent pipe into the body of
the apparatus, and also the employment of the delivery end of this pipe as a bolt
for securing the cover to its place substantially as herein before described and
shewn in the accompanying drawings
(7) Arranging the channels for the mercury or other suitable fluid in annular
concentric rings joined by a duct or passage (or ducts or passages) so that while
they require a minimum of mercury to fill them, they always maintain the same
level of surface throughout, substantially as hereinbefore described and illustrated
in the accompanying drawings

page_text: (8) The combination of a pressure governor similar to that shewn at 6 figure 1,
with the valve of an automatic gas lighting apparatus, substantially as hereinbefore
described and illustrated in the accompanying drawings
(9) The manner of producing a constant lower pressure than that within the
bell of an apparatus fitted with a governor of the kind described by means of
throttling the gas between the outlet from the bell and the burner, all substantially
as herein before described and illustrated in the accompanying drawings
(10) The method of guarding the small permanent flame of such an apparatus
by means of a casing substantially similar to that illustrated in figures 8 and 9 of
the accompanying drawings.