IMPROVEMENTS IN GAS METERS
Year: 1859

page_text: LETTERS PATENT to James Farquhar, of the City and County of
Aberdeen, North Britain, Clerk, for the Invention of "IMPROVEMENTS IN
GAS METERS."
PROVISIONAL SPECIFICATION left by the said James Farquhar at the
Office of the Commissioners of Patents, with his Petition, on the 10th
December 1859.
I, JAMES FARQUHAR, of the City and County of Aberdeen, North Britain,
Clerk, do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN GAS METERS," to be as follows, that is to say:-
This Invention relates to various mechanical arrangements and means
applicable in the construction and working of wet gas meters for the purpose
especially of maintaining the liquid level in such meters, and for securing other
advantages in the practical operation of the meters. Under the first head of
this Invention the improvements consist in the adaptation of the principle of
what is generally known as the "Fountain lamp," or such lamp as is arranged
with the oil above the light for the maintenance of a constant or nearly.
constant water level in wet gas meters, and by which adaptation all or nearly all
the space above the water level in the chamber formed against the drum case
usually termed the front of the meter, may be used as a fountain to contain
water to maintain a constant or nearly constant water level in the drum case.

page_text: The communication between the front and the drum case is of the same nature
as in the fountain lamp, that is to say, the upper edge of the passage or
passages is made at the level or nearly at the level at which the water in the
drum case is to bo maintained. The action is the same as in the lamp;
whenever the water in the drum case descends below the true water level a
few bubbles of air or gas pass through from the drum case to the fountain,
and displace water therein, which water passes into the drum case, and restores
the level. The fountain is filled at the usual feed pipe in meters, and when
the fountain is filling the air is carried off by a passage commencing with the
top of the inside of the fountain, and with the atmosphere outside the meter.
After filling the meter in the usual way, the manner of filling the fountain is
as follows:-All ingress or egress to and from the meter is closed except the
feed pipe, and the passage by which the air is carried off whilst the fountain is
filling, after the fountain is filled the passage for carrying off the air is made
air-tight, a cock or two at the burners opened, the waste water plug taken
out, the waste water run off; the meter is then ready for action.
The second part of the Invention consists in using a vessel open at one end,
and of any shape, as a float to open and shut the inlet valve. The third part
of the Invention consists in a bent pipe connected with the pipe which intro-
duces the gas into the drum, and carried upwards to the top of the interior of
the fountain; and connected with the former a little below the level at wbich
the gas enters the drum is another bent pipe, which is carried to the outside
of the meter also at a point a little below the level at which the gas enters the
drum; through this pipe the waste water flows. The bends in the pipes form
such a depth of hydraulic seal that the water cannot be forced out by the
pressure of the gas, and if suction be applied the waste pipe is only partly
emptied, as there is no pressure in the fountain in that direction, and conse-
quently no gas can be extracted from the meter in that way. In these
improved wet gas meters the waste water box is dispensed with, and the front
is carried down as low or nearly as low, or below the lower part of the drum
case, and the entire space, or nearly the entire space below the water level is
then made an open communication between the front and the drum case. To
prevent tilting, the pipe which introduces the gas to the drum is placed as far
as is convenient in front of the drum, in a horizontal or nearly horizontal
position, so that when the meter is tilted water flows into it (at the open
mouth which is inside the drum), and stops the
passage
of
the gas.