CERTAIN IMPROVEMENTS IN GAS METERS
Year: 1820

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
MALAM, of Romney Terrace, Horseferry Road,. Westminster, in the County
of Middlesex, Engineer, send greeting.
WHEREAS His most Excellent Majesty King George the Fourth did, by
His Letters Patent under the Great Seal of that part of the United Kingdom. of
Great Britain and Ireland called England, bearing, date at Westminster, the
Eleventh day of May, in the first year of His reign, give and grant unto me, the
said John Malam, my exors, adiñors, and assigns, His especial licence, full power,
sole privilege and authority, that I, the 'said John Malam, my exors, admors,
and assigns, during the term of years thercin mentioned, should and lawfully
might make, use, exercise, and vend, within England, Wales, and the Town of
Berwick-upon-Tweed, and also in all His Majesty's Colonies and Plantations
abroad, my. Invention of "CERTAIN IMPROVEMENTS IN GAS METERS;" in which
said Letters Patent there is contained a proviso that if I, the said John Malam,
shall not particularly describe and ascertain the nature of my said said Inven-
tion, and in what manner the same is to be performed, by an instrument in
writing under, my hand and seal, and 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 Letters Patent, that then the said
Letters Patent, and all liberties and advantages whatsoever thereby granted,
shall utterly cease, determine, and become void, as in and by the same, rela-
tion 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 Malam, 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 Drawings hereunto annexed, and the following
description thereof (that is to say) :-
:-
In Drawing No. 1, Fig. 1 is a longitudinal section of one of my improved
gas meters, and which I prefer to make of tinned iron, or other fit and proper
material; Fig. 2 is a plan of it; and Fig. 3 an end view and section of
the same, in all of which Figures the same letters refer to the same parts of
the machine.
A, A, &c. is the outer box or case of the measurer, having a tube or pipe
at B to admit the gas from the gasholder or main, and another tube or pipe
at C to suffer it to pass to the burner. In the outer case is enclosed another
case D, D, &c., having a moveable lid or cover E, E, turning upon hinges at
F, F, and made of tinned iron or other proper material. The sides and one
end of the inner case are formed of linen, silk, or other flexible material
doubled, and which are rendered air-tight in the manner to be described
hereafter. The gas passes through the pipe B into the inner case D, D, and
passes into the outer case A, A, through the pipe or orifice G, which is opened
or closed in the following manner :-H is a flat plate of metal supported upon
a stud or rod of wire I, affixed upon the bottom of the outer case A, A, at
such a height as for the end of the pipe or orifice G to come into contact
with it on the descent of the plate or cover E, E, of the inner case and to
close it, which closure is further promoted by the following means:-The
plate H has a socket J underneath it, which fits loosely upon the wire I, so as
to ply or yield a little, and enable the plate H to accommodate itself to the flat
bottom of the pipe G; and to make it more perfectly gas-tight, the top of the
plate H may have an oiled leather or other soft and elastic material affixed
upon it. The gas enters the machine at B and raises the cover E, E, and
the tube or orifice G is then opened, and the gas passes through the machines
to the burners, as indicated by the arrows. In this case the opening or
closing of the orifice at G becomes the measurer of the gas passing through
it, as the same difference of pressure is always maintained by the weight of
the cover E, E, being at all times nearly the same.
It being necessary,
however, to register the quantity of gas passing to the burners through the
orifice at G, I now describe one of the means employed by me to do this;
and first, to mention that the quantity of gas which passes is in proportion to
the size of the orifice at G, and as that orifice cannot be enlarged or con-
tracted but by the rising or falling of the cover E, E, I connect that cover

page_text: with the registering part of the machine in the following manner:-K is a
rod united by the joint L at its lower end to the cover E, E, and by the joint.
M at its upper end to the arm N, turning upon an axis at O as a centre..
This axis O passes through the side of the recess P (which is sunk beneath.
the lid of the case A, A,) in such a manner as to communicate motion within.
it, but at the same time to prevent any gas escaping that way. This is effected
in the following manner-Upon the axis O, and near one extremity of it, is-
formed a cone Q, which is accurately ground air-tight into the conical hole R
made in the side of the recess P, and the cone Q is pressed or kept in the
hole R by the action of the cleft spring S against a shoulder made on the
opposite extremity of the axis O. On the conical end of the axis O, within.
the recess P, is fixed another arm T, having a joint U at the end of it, which
is connected to the lower end of the rod V, V, the upper end of which is.
guided in the eye or loop W, which is fixed in one of the end plates of the
cylindrical case X, which contains the maintaining power which gives motion
to the register, as will be described hereafter. The rod V, V, is composed of:
two parts, united together by the screwed socket Y, having right and left.
threaded female screws within it, which screw upon right and left male screws.
made upon the ends of the pieces which form the ród V, V, and by turning
the socket Y either way the rod V, V, may be lengthened or shortened as
may be necessary for its adjustment. The cylindrical case X of the maintain-
ing power is supported by its feet Z, Z, being affixed upon the top of the.
case A, A, and the maintaining power itself consists of a spring in its barrel,.
with a band or chain acting upon a fuzee, and a train of wheels, pinions, and
a balance wheel, as is usual in timepieces, and need not therefore be described:
here, its office being merely to give an uniform rotatory movement to the
axis a carrying the eccentric wheel b, which operates upon the lever c so as:
to raise or lower it, as hereafter described. The lever c moves upon the axis.
of the wheel d as a fulcrum, and its other end is guided in a slit or groove
made in the piece e, which is screwed to the plate X to steady it. To the
lever c is affixed a stud f, having a slit or cleft in it which holds a slight
spring g, the end of which, on the lever c being depressed, presses upon the
cylindrical rim of the wheel d and turns it more or less, according to the
greater or lesser movement of the lever c, and the wheel is retained in that
situation between each movement by the pressure of another similar spring h
affixed in a stud i rivetted in the plate X. Upon the axis of the wheel dis
a pinion j, which drives a toothed wheel k, the hollow axis or socket of which
upon a stud affixed in the plate X, and carries an index m, which
points out the quantity of gas passed through the machine upon a graduated
turns

page_text: and numbered dial plate n. One end of the axis of the wheel d works in a.
pivot hole made in the plate X, and the other end in a pivot hole made in
the cock o, which is screwed to the plate X. I have found by experiments
that equal quantities of gas pass through a given orifice in equal times if the
same difference of pressure be maintained, and that, consequently, the quan-
tities of gas passed through different-sized orifices under. the same circum-.
stances will be proportioned to those orifices. The orifice G, which is the
measurer of the gas, adapts itself to the supply required, and thus, when only
half open, as here shewn of course only half the quantity of gas passes through
it in a certain time as would do were it quite open. In the rod V, V, is fixed
a projecting arm or stud p, upon which the lever c rests, when not acted upon
by the eccentric wheel b, as is shewn by the dotted line, and its greater.or
lesser degree of motion is governed thereby, and consequently also the action
of the spring y upon the wheel d, which is moved accordingly at each revolution
of the eccentric wheel b; or, in other words, the length of the strokes of the
lever c is in proportion to the size of the orifice G, and the quantity of gas
passed through the machine is registered accordingly. When the supply of
gas to the machine is cut off the cover E, E, will., descend and close the
orifice G, at the same time the rod V, V, will ascend and lift the lever c so
high as to be just out of reach of the eccentric wheel b, and consequently it
cannot be acted upon by it, nor the registering proceed. As, however, it is
not desirable for the maintaining power to waste or expand itself during the
inaction of the register, a second arm q is fixed into the rod V, V, which
works into a groove or slit made in a hook or catch r, turning, upon a stud
affixed in the plate X, and lifts that catch when the rod is raised up to its
greatest height, so as that an arm or stud s, which is fixed in the face of the
eccentric wheel b, lodges in a notch or gap in the hook r, and stops the motion
of the maintaining power. When, however, the gas again begins to pass
through the machine the cover E, E, ascends and lowers the rod V, V, and
the catch connected with it is disengaged from, the studs in the eccentric
wheel, and the maintaining power is again set in motion. To prevent the
passage of gas through the machane when the maintaining power is exhausted
and the movement requires to be wound up, the following contrivance is made
use of to close the orifice G-On the axis t of the fuzee of the maintaining
power is a pinion u, which acts: in a toothed segment or arc v, turning upon
an axis at w, affixed to the top.of the case A, A; on the axis of this segment
is a tooth x, which encounters. or. acts' against another, tooth y upon one end
of the axis z, on the other end of,which axis is an arm or lever 1, which lies
close to the rod V, V, and when the movement of the maintaining: power is

page_text: nearly stopped, or the spring unwound, the pinion u on the axis of the fuzee
will have moved the segment or arc v sufficiently far for the tooth a to act
upon the tooth y, and raise up the lever or arm 1 until it rests against or
comes into contact with.a stud 2, which is fixed upon the screwed socket Y
of the rod V, V, thereby raising that rod and closing the orifice G. On wind-
ing up the movement of the maintaining power the tooth is released from
contact with the tooth y by the pinion u moving the arc v in the contrary
direction.
I shall now proceed to describe the manner in which I render the union of
the flexible material forming the sides and ends of the inner case D, D, with
the top or cover E, E, and with the bottom of the outer case A, A, air-tight.
Around the edges of the cover E, E, is made, of metal or other proper material,
a horizontal groove 3, 3, &c., and likewise upon the bottom of the outer case
A, A, is made a vertical groove 4, 4, &c., at- the end near the hinges F, F,
the grooves 4, 4, are carried up vertically, and a horizontal one is carried
across the end, close to the hinges; into these grooves the edges of the
flexible material are introduced, they being previously coated with pitch, wax,
rosin, or a composition of these matters in a softened state; and the edges of
the grooves are to be closed upon them by pressing or hammering them
together, and when the cement is become hard the union is effected. I
render the flexible material itself air-tight by saturating it either. with the
essential oil obtained from the distillation of coal tar, or with animal or
vegetable oil mixed with coal tar, so as not to be liable to injury from the gas.
in passing through the inachine.
Fig. 4 is a view of the top of the case containing the spring movement of
the maintaining power, and of the wheelwork and levers affixed to it, the same
letters referring to the same parts as in Figs. 1, 2, and 3.
F
Fig. 5 is a representation of the pinion u and toothed arc v.
I
Fig. 6 is an edge view of the eccentric wheel band its stud s.
Fig. 7 an edge view of the guide piece e for the lever c to move in; and.
Fig. 8 an edge view of the rod V, V, with its screwed socket Y and stud 2,.
and its two other arms p and q.
In Drawing No. 2, Fig. 9 is a longitudinal section of another of my
improved gas meters, Fig. 10 a plan of it, and Fig. 11 a transverse section
thereof, the same letters and figures referring to the same parts of the
machine in this Drawing, as well as to those parts of it which are also similar
to the machine described in the references to Figs. 1, 2, and 3 of Drawing
No. 1. It will therefore now only be necessary to describe those parts of the

page_text: machine shewn in Figs. 9, 10, and 11 of Drawing No. 2 which differ from
the former one shewn in Figs. 1, 2, and 3 of the Drawing No. 1, and in the
first place, to state that I close the sides and ends of the inner vessel D, D, by
means of the method commonly known by the name of the water joint.
5, 5, &c. is the groove or channel, to be filled with water, alcohol, mercury, or
other fit and proper fluid. This groove is made around the inside of the
bottom of the vessel A, A, leaving, however, a space 6, 6, at the end C for the
passage of the gas to the pipe C. From the lid or cover of the inner vessel
E, E, descends a border, rim, or ledge of metal 7, 7, &c., which dips beneath
the surface of the fluid in the groove 5, 5, &c., and renders the inner vessel
D, D, air-tight, allowing the lid of it E, E, also to rise or fall freely upon its
hinges E, F. I also substitute as a maintaining power for the movement of
the register in this machine, in place of that before described, an instrument of
my invention, which has hitherto been used as a gas meter, and described 'and
published as such in the 37th volume of the Transactions of the Society insti-
tuted in London for the Encouragement of Arts, Manufactures, and Commerce,
and also in a work entitled "The Theory and Practice of Gas Lighting," by
Thomas Snowden Peckston, published in the year One thousand eight hundred
and nineteen, and to which works I refer for a particular description of that
machine. I do not however mean or intend to use it for that purpose in the
machine now specified, but merely, as above stated, as a maintaining power for
the register. As there is in this machine, as well as in that before described,
a greater pressure of gas within the inner vessel D, D, than of that in the outer
case A, A, occasioned by the weight of the lid E, E, which is constantly uniform,
as before described, the gas will pass up a pipe 8, 8, which leads from the inner
vessel D, D, and will enter the inner cylinder 9 of the revolving wheel of the
maintaining power or mover of the register, as indicated by the arrows, and
will enter into the compartments 10, 10, &c. in that wheel in succession, as
the openings into them rise above the surface of the water, alcohol, or other
fluid 11, 11, in the upper vessel, and thus gives motion to the wheel in the
direction shewn by the arrows, the gas escaping from each compartment
through openings in the periphery of the wheel into the case surrounding the
wheel, and from thence down the pipe 12, 12, into the outer case A, A, of the
measurer, where it mixes with the other gas, which passes through the pipe C
to the burners, the motion of the wheel being rendered uniform by the constant
pressure of the lid E, E, upon the gas in the inner vessel D, D. The axis a
of the revolving wheel passes through a stuffing box 13, which is fixed in the
side plate X of the wheel case, and upon this axis is fixed the excentric wheel

page_text: b, which operates upon the lever c in the same manner as in the machine
before described. It will not be necessary, however, to employ the means
there used for stopping the movement of the wheel, as when the gas ceases to
pass through the machine the wheel stops of itself.
Fig. 12 is a view of the end plate X of the case of the maintaining power
of the register, and of the parts connected with it.
Fig. 13 shews a different form given to the orifice G in the lid E, E, and
also a parabolic solid 14, which is substituted in place of the plate H, as it
will allow of a greater degree of motion in the lid E, E, to close or open the
orifice G than where the plate H is used.
Fig. 14 is another method of constructing the orifice G in the lid E, E, the
tube G, G, having a slit 15 in one side of it, and being made to dip into a
cup 16 containing water, alcopol, mercury, or other proper fluid, and which
said cup is fixed upon the bottom of the case A, A, the orifice or slit 15 being
enlarged or contracted by the ascent or descent of the lid E, E.
In Drawing No. 3; Fig. 15 a section of another contrivance for giving
motion to the register, and Figure 16 is a transverse section thereof. In this
machine the lid E, E, of the inner vessel D, D, is also rendered air-tight by
the flexible material described in the references to the Figures of Drawing
No. 1; but instead of the orifice G and plate H a passage through the
joint substituted for the hinges F, F, is here employed, and which joint is
formed in the following manner: To the end F of the lid E, E, is affixed the
metal cylinder 17, 17, having pivots 18, 18, at each end thereof, turning in
sockets 19, 19, affixed to each side of the case A, A. The cylinder 17, 17,
has a slit or opening in and through the middle of it at 20, 20, which is made
wide above, and narrow below. There is also affixed to the end of the outer,
case A, A, a piece of metal 21, 21, the inside of which is made a portion of a
hollow cylinder, corresponding in diameter with the cylinder 17, 17; and so
placed as that when the lid E, E, is depressed the piece of metal 21, 21,
presents itself before the smaller part of the slit 20, 20, in the cylinder
17, 17, and closes it, so as to prevent the passage of gas through it; but
when the lid E, E, is raised more or less the orifice or slit 20, 20, is opened
accordingly, and becomes the measurer of the gas passing through it. Motion
is given to the register of this machine in the following manner :-The gas
passes up the pipe 8, 8, as shewn by the arrows, and enters through the
opening 22 made in the side of the vertical elbow 23 into one of the passages
leading into the six pairs of bellows 24, 25, 26, 27, 28, and 29, which are
affixed upon an axis 30, which is made hollow, and fits upon the elbow 23 of

page_text: the pipe 8, 8, the end of it being made. a little conical, as well as the hollow
end of the axis 30, and ground so as to fit together air-tight.
The passages
or slits in the axis 30 are long enough to cover the opening 22 in the elbow
pipe 23, already described, and another opening 31, made in the opposite side
of the elbow pipe, but between the openings 22 and 31; the elbow pipe is
closed by a partition plate 32 within it, so that the gas is entering into that
pair of bellows, the opening into which is passing over the orifice 22, and at
the same time is escaping out of the opposite pair by the other opening 31
through the hollow axis 30, as indicated by the arrows, and mixes with the
other gas passing through the machine. to the burners. The six pairs of
bellows have each loose metal plates 33, 33, &c., and which are connected
with other plates 34, 34, &c.; affixed upon the axis 30 by similar flexible
materials to those already described, and which are also united to the
end and side edges of the plates 33 and 34 by metal grooves, in the
manner already described, so as to be air-tight, and the wheel thus formed
of bellows revolves upon its axis in the direction shewn by the arrows
around its periphery, in consequence of its equilibrium being destroyed,
in the following manner:-The gas is shewn in Figure 15 as entering
the bellows 24, and causing its moveable plate 33 to quit its vertical position;
and assume an inclined one, which throws it out of its centre of gravity,
and causes the wheel to turn in order to restore the equilibrium. In
like manner the gas next enters the bellows 29, and the others in succes-
sion, and thus an uniform motion of the wheel is produced, the bellows
emptying themselves constantly on the opposite side of the centre to that at
which they are filled, and which effect is promoted by the weight of the
moveable plates 38, 33, &c. pressing out the gas through the opening 31, as
already described. The axis of the bellows wheel passes through a stuffing
-box in the plate X, and carries the eccentric wheel 6 upon it, which effects the
registering of the gas, in the manner already described.
b
Figure 18 is an end view of the hollow axis of the bellows wheel, shewing
its pivot, fixed in the centre of four arms, so as to leave a passage for
the gas.
:
In witness whereof, I, the said John Malam, have hereunto set my hand
and seal, this Eleventh day of November, in the year of our Lord
One thousand eight hundred and twenty.
JOHN (L.S.) MALAM.

page_text: AND BE IT REMEMBERED, that on the Eleventh day of November,
in the year of our Lord 1820, the aforesaid John Malam came before our
said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Specification aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Eleventh day of November, in the year of our Lord One
thousand eight hundred and twenty.