IMPROVEMENTS IN THE CON- STRUCTION OF WET GAS METERS
Year: 1860

page_text: LETTERS PATENT to Edward Bridgman, of Tarragona, in the Kingdom
of Spain, Gentleman, for the Invention of "IMPROVEMENTS IN THE CON-
STRUCTION OF WET GAS METERS."
Sealed the 12th February 1861, and dated the 20th August 1860.
PROVISIONAL SPECIFICATION left by the said Edward Bridgman at the
Office of the Commissioners of Patents, with his Petition, on the
20th August 1860.
I, EDWARD BRIDGMAN,. of Tarragona, in the Kingdom of Spain, Gentle-
man, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN THE CONSTRUCTION OF WET GAS METERS," to be as follows:-
The object of this Invention is to ensure a more accurate measurement of
gas than is commonly attained in wet gas meters, and also to prevent such
meters from being tampered with for fraudulent purposes. The inlet tube for
the gas is fitted with a valve, which is carried by a rock lever, to the inner end
of which a saddle-shaped float is attached. This float is made saddle-shaped
that it may override the horizontal bend of the spout by which the water is
supplied to the meter. Within this spout, or close adjacent thereto, is a small
pipe which gauges the height of the water line in the meter, and this pipe is
so situate that it stands up within the measuring drum midway, or nearly so,
between its sides, the object being to get this pipe so near the middle of the

page_text: meter case that the tipping of the meter in any direction will not materially
change the relative positions of the water level and the top of the pipe. The
outlet tube for the gas is fitted like the inlet tube with a cut-off valve carried
by a rock lever, which is fitted with a saddle-shaped float. This float rides
over the drum axle, one end of which has its bearing in a cross piece at the
back of the meter, and the other end in a support near the centre of the meter.
The drum consists of an inner and outer periphery, the space between which
is divided into four measuring chambers by diagonal partitions, and closed in
by side plates overlapping each other as usual. The central space of the drum
is divided by a central vertical division plate, and on either side of this plate is
an opening into each measuring chamber for the admittance of the gas to be
measured, and its exit when measured. In order effectually to seal these open-
ings, hoods are applied over them, so that the inlet openings in leaving the water
remain sealed until the side entrance to the chamber is also uncovered, and the
sealing of the exit openings in the bottom and side of the measuring chamber
will also by this means take place simultaneously, or nearly so. Instead of
hoods for sealing the openings the lips of the openings may be continued in
the line of direction of the partitions, towards the centre of the drum, leaving
sufficient space for the entrance and exit of the gas, and the free circulation of
the water through the chambers. The vertical division plate may also, if
thought desirable, be removed, and the openings into the chambers from the
centre of the drum extended across the inner periphery. The openings must,
however, be sealed by the means above indicated.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Bridgman in the Great Seal Patent Office on the 2
20th February 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
BRIDGMAN, of Tarragona, in the Kingdom of Spain, Gentleman, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters 3
Patent, bearing date the Twentieth day of August, in the year of our Lord
One thousand eight hundred and sixty, in the twenty-fourth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
Edward Bridgman, Her special license that I, the said Edward Bridgman, my
executors, administrators, and assigns, or such others as I, the said Edward 3
Bridgman, my executors, administrators, and assigns, should at any time agree.

page_text: with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN THE CON-
STRUCTION OF WET GAS METERS," upon the condition (amongst others) that I,
the said Edward Bridgman, by an instrument in writing under my hand and
seal, 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 Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Edward Bridgman, do hereby declare
the nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Drawings hereunto annexed, and to the
letters and figures marked thereon (that is to say) :-
.
The object of this Invention is to ensure a more accurate measurement of
gas than is commonly attained in wet gas meters, and also to prevent such
meters from being tampered with for fraudulent purposes. These results I
obtain, first, by the use of certain improvements in the construction of the
measuring drum; and, secondly, by causing the water gauge pipe to stand up
within the measuring drumn midway, or nearly so, between its sides; this pipe
will thus be so near the middle of the meter case that the tipping of the
meter in any direction will not materially change the relative positions of the
water level and the top of the pipe.
In Sheet I. of the Drawings I have shewn an arrangement of meter, by
which both the above named, results may be attained.
Fig. 1 is a vertical section of the meter, taken in the line of the axis of the
drum; Fig. 2 is a. side view of the same, with the end casing cut away to
shew the arrangement for supplying and cutting off the gas, and regulating the
height of the water in the meter; Fig. 3 is a plan view of the apparatus for
regulating the supply of gas to the meter, and determining the height of the
water line; and Fig. 4 is a view of the measuring drum with the cover
removed.
.I will first describe the means whereby I maintain the level of the water in
the meter, and I will then explain the nature of my improvements in mea-
suring drums.
a (Figures 1 and 2) is the inlet tube for supplying gas to the meter. In
this tube is a valve seat fitted to receive an inverted valve b, which is carried
by a bent rock lever, c, shewn best at Fig. 3, and having its fulcrum ou a

page_text: bracket attached to the casing A of the meter. This rock lever carries a
saddle-shaped float d, which overrides the horizontal portion of a bent gas and
water supply pipe or spout e, which is connected to the pipe a by a branch a¹,
thus avoiding the necessity for the usual front chamber. Into the spout e
enters a syphon pipe f (Fig. 2) connected to the water supply pipe g. The
spout e is made duplex in one part by the addition of a pipe e, which dips
into the syphon pipe f, and reaches upwards to the height required for the
water level, and serves to gauge the water to that level, the overflow passing
into the syphon pipe f, and thence through the open mouth of the tube g out
of the meter. The tube g is then closed with a screw plug as usual. The
pipe e extends somewhat higher than the pipe e', so as to secure a free passage
upwards for the gas. The mouth of the pipe e', it will be seen, is by this
arrangement brought so near the centre of the meter case as to prevent any
appreciable change being effected in the level of the water as respects the
mouth of the pipe e¹ by the tipping of the meter. Over the spindle B of the
measuring drum C, and within a central chamber formed therein, a saildle-
shaped float h rides. To this float is attached a rock lever i, which carries an
inverted valve; k, l, is the gas exit pipe, fitted with a sent to receive the
valve k. It will now be understood that when by reason of an undue supply
of water to the meter the measuring space for the gas is contracted, a ten-
dency will be imparted to the floats d and h to rise, and in so rising they will
close both the inlet and exit gas pipes and stop the action of the meter.
I will now describe the mode of constructing the drums of meters so as to
ensure a steady even movement, and a correct measurement of the gas passed
through the meter. The spindle B of the drum C is mounted in bearings, the
one attached to the end casing of the meter and the other to the spout e. The
drum consists of an outer periphery 1, and an inner periphery 2, which are
connected together by the usual overlapping side covers 3, 3. The inner peri-
phery 2 forms à central chamber, which is divided by a vertical partition 4,
which prevents the gas entering the back division until it has passed through
the measuring chambers in the drum. These chambers are shewn as four in
number, and they are separated from each other by cross partitions 5, 5, which
extend diagonally across the drum. The inner periphery 2 is pierced with
holes, as shewn best at Figures 5 and 6, Fig. 5 shewing the plate used to form
the periphery as laid out flat, and at half the size of Figures 1 and 3; and
Fig. 6 shewing it in plan, as coiled into a cylinder. From these views it will
be seen that there are two openings 6, 6 into each chaniber from the centre of
the drum, the opening on one side of the partition 4 being for the admission
of "gas to the chamber, and that on the other side of the partition for the exit

page_text: of the measured gas.
These openings are severally covered by an open-.
mouthed hood 7, the lips of which terminate in a line with the open lips of the.
adjacent side covers of their respective chambers. Thus these openings will
remain sealed until the moment the drum by its rotation brings up the lip of
the lateral inlet or outlet opening of each successive chamber.
At Fig. 4. I have shewn the extent of one chamber by red colour. Into.this
chamber the gas is now passing both by the lateral opening at 3* leading.
thereto, as shewn by the arrow, and also. by the.hood 7. When by the con-
tinued rotation of the drum this line 3*, 7* is brought under the water line,
the chamber will be closed and the gas contained therein will be confined until
the line 3*7** comes above the water. As soon as this happens the water
will enter the chamber through the openings 3*, 7*, and force out the gas at the
opening 6 on the other side of the central partition. The same action will take
place with respect to all the measuring chambers in succession, the inlet pas-
sages receiving gas as they emerge from the water and the outlet passages,
giving off the measured gas. The rotation of the drum sets the counting
apparatus in action by means of a worm and worm wheel m, n, Fig. 1. The
hollow cover 8 of the drum is formed with a cylindrical recess to receive the
float d, and a hole is made as usual in the cover for the spout e to pass through
to the centre of the drum; o is a stay stretching across the interior of the drum
for the purpose of strengthening it.
In Sheet II. I have shewn some modifications of the measuring drum.
Fig. 7 is a side view of an arrangement with the side covers removed; and
Fig. 8 is an edge view of the same, with a part of the periphery broken away
to shew the openings in the inner periphery. The reference numbers in this
Sheet represent corresponding parts in Sheet I. In this arrangement there is
the central division plate 8; but the openings in the inner periphery, instead of
being covered by hoods, are surrounded by lips 7, 7, formed of flat plates,
which are set parallel, or nearly so, with the adjacent sides and ends of their
respective measuring chambers. These lips project into the water and keep
these openings always sealed; their use is therefore confined to admitting
water into the measuring chambers to expel the measured gas. In other
respects the drum is constructed and operates precisely as that described with
reference to Sheet I. The opening 6 may, however, be extended across the
drum, as shewn in partial section, Fig. 9, where the central partition is
removed.
. A further modification is shewn at Figures 10 and 11; Fig. 10 being a side
view. of the drum, with the side plates removed; and Fig. 11 an edge view,
with a portion of the periphery broken away. The openings 6 in the inner
=

page_text: periphery extend across the drum, and they are sealed by means of lips 7, 7,
the longitudinal plates of which are curved, as shewn at Fig. 10, to facilitate
the flow of the water into and out of the measuring chambers. The diagonal
plates which divide the space between the outer and inner peripheries of the
drum are continued to near the centre of the drum, so that they divide also the
space formed by the sealing lips 7, thus making each set of lip plates 7 answer
for two adjacent openings in the periphery 2.
⚫ Having now set forth the nature of my Invention of." Improvements in
the Construction of Wet Gas Meters," and explained the manner of carrying
the same into effect, I wish it to be understood that under the above in
part recited Letters Patent, I claim,-
First, the arrangement above described for securing wet meters from being
fraudulently tampered with..
And, secondly, constructing the measuring drums of wet meters in the
manner above described.
In witness whereof, I, the said Edward Bridgman, have hereunto set my
hand and seal, the Fifteenth day of February, in the year of our
Lord One thousand eight hundred and sixty-one.
EDWARD BRIDGMAN. (L.S.)