IMPROVEMENTS IN GAS METERS
Year: 1878

page_text: LETTERS PATENT to Henry Thomas, of Oldham, in the County of Lancaster,
for the Invention of "IMPROVEMENTS IN GAS METERS."
PROVISIONAL SPECIFICATION left by the said Henry Thomas at the
Office of the Commissioners of Patents on the 18th January 1878.
HENRY THOMAS, of Oldham, in the County of Lancaster.
GAS METERS."
"IMPROVEMENTS IN
The object of this Invention is to secure the more correct measurement of gas by
causing the whole surface of the water or other liquid in the meter to remain as
nearly as possible at the same level under varying conditions of pressure and rates
of discharge of the gas; to maintain the same correct level by instant compensation
for any loss of water by evaporation or otherwise, and to provide means whereby
the extraction of unregistered gas is prevented.
These improvements consist in so forming the partition which divides the front
or float chamber from the chamber in which the measuring drum revolves, that the
inlet gas has free access to both, and the placing of a screen or mid-feather in such
a position as to allow the gas to flow more readily towards the openings in the
measuring drum. The measuring drum is retained in the position ordinarily
adopted, but its action is reversed, and a bent tube is attached to the spout by
means of which the gas after entering at the back hoods and passing through the
drum is conveyed to the outlet. This arrangement is applied in combination with a
compensating float of a semi-circular form (to which is attached a valve) with its
axis fixed in such a position that the descent of the float instantly restores the
water level and thus compensates for any loss of water.
In addition to the foregoing the waterline pipe is placed in the front box, and as
the bottom end of it is carried down into the waste water-box and is sealed therein,
the possibility of drawing off unregistered gas through the waste water outlet is
completely prevented.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Henry Thomas in the Great Seal Patent Office on the 17th
July 1878.
HENRY THOMAS, of Oldham, in the County of Lancaster.
GAS METERS."
"IMPROVEMENTS IN
The object of this Invention is to secure the more correct measurement of gas by
causing the whole surface of the water or other liquid in the meter to remain as
nearly as possible at the same level under varying conditions of pressure and rates
of discharge of the gas; to maintain the same correct level by instant compensation
for any loss of water by evaporation or otherwise, and to provide means whereby
the extraction of unregistered gas is prevented.
These improvements consist in so forming the partition which divides the front or
float chamber from the chamber in which the measuring drum revolves, that the
inlet gas has access to both, and the placing of a screen or mid-feather in such
a position as to direct the gas to flow through an opening in the partition into the
drum chamber, and towards the openings in the measuring drum. The measuring
drum is retained in the position ordinarily adopted, but its action is reversed, and a
bent tube may be attached to the spout, by means of which the gas after entering
at the back hoods and passing through the drum is conveyed to the outlet, or, by
preference, as shown on the Drawing, the gas may pass from the spout or spouts
into the upper part of the waste water box, and from thence through a channel or
conduit to the outlet. This arrangement is applied in combination with a compen-
sating float of a semi-circular form (to which is attached a valve) with its axis fixed
in such a position that the descent of the float instantly restores the water level
and thus compensates for any loss of water.
In addition to the foregoing the water-line pipe is placed in the front box, and
as the bottom end of it is carried down into the waste water box and is sealed
therein, the possibility of drawing off unregistered gas through the waste water
outlet is completely prevented.
In order that the foregoing may be more easily understood, Drawings are
attached hereto, of which the following is a description.
Fig. 1 is a front elevation of the meter with the front plate of the case
removed.
Fig. 2 is a vertical section of the outer case, and shows the arrangement of the
various internal parts; and Fig. 3 is a front elevation, with the front plate of the
case and the compensating float removed.
In each of the Figures similar letters of reference relate to the same parts.
A is the case of the meter; B, the inlet, with its valve seat and opening C and
screen D; E is the partition separating the front box from the drum chamber, and
has an orifice F for the admission of gas to the latter; G is the drum or measuring
wheel, and H the hollow cover under which one or more spouts I, I, are placed. By
this spout or spouts the gas is delivered into the upper part of the waste water box
J, and from thence it flows in the direction of the dotted arrows to the channel or
conduit K, and to the outlet L. M is the semi-circular compensating float, with its
valve N; and O is the water-line pipe, the bottom of which is sealed in the syphon
box P; Qrepresents the level of the water line in the front box, and R the water
line in the waste water box, S being the waste water box plug; T is an oval orifice
in the partition for the admission of gas from the drum chamber to the front box,
and U is a flat bar to support one end of the float spindle; V is the water filling
tube, and W the plug for drawing off the water from the body of the meter.
From the foregoing it will be seen that the gas flows from the inlet through the
valve opening C direct into the chamber containing the measuring drum, a portion
subsequently entering the front box by the oval hole or other shaped hole or holes
in the partition. The gas that is in the drum chamber now enters the drum by the
slits in the hoods, is measured, and then passes into the hollow cover, and from

page_text: thence down the spout or spouts to the upper part of the waste water box, and on
to the outlet, as before described;
It will be seen, therefore, that the water in the waste water box is subjected to
the outlet pressure, and consequently it remains undisturbed. The water-line pipe
being placed under the screen loss of water from over-working of the meter is pre-
vented, and being sealed at its other extremity, as shown on the Drawings, it is
impossible to draw off water therefrom by syphoning or otherwise. It will be
observed, too, that the screen D prevents any gas from entering the front box
except by the oval hole T.
Meters made with semi-circular compensating floats are not new, neither is the
reversal of the ordinary action of the drum new, but the combination of a semi-
circular compensating float with a drum that is retained in its ordinary position,
but whose action is reversed, together with the screen before described, and the
arrangement for preventing the abstraction of water or gas from the waste water
box, is new.
Having now described and particularly set forth the nature of this Invention,
and the manner in which the same is or may be used or carried into effect, I would
observe in conclnsion that I do not confine or restrict myself to the precise details
or arrangements which I have described or referred to, as variations may be made
therefrom without deviating from the principles or main features of this Invention,
but what I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent, is the construction
of meters with semi-circular compensating floats in conjunction with drums occu-
pying the ordinary position, but whose action is reversed, and in combination with
screens and an arrangement for the prevention of the abstraction of water or gas
from the waste water box, as herein described and shown on the Drawings.
In witness whereof, I, the said Henry Thomas, have hereunto set my hand
and seal, this Sixteenth day of July, in the year of our Lord One
thousand eight hundred and seventy-eight.
TENDY THOYL
HENRY THOMAS. (LS.)