IMPROVEMENTS IN GAS METERS
Year: 1866

page_text: LETTERS PATENT to William Willmer Pocock, of Craven Street, in the
City of Westminster, Architect, for the Invention of "IMPROVEMENTS
IN GAS METERS."
Sealed the 24th July 1866, and dated the 27th January 1866.
PROVISIONAL SPECIFICATION left by the said William Willmer Pocock
at the Office of the Commissioners of Patents, with his Petition, on the
27th January 1866.
I, WILLIAM WILLMER POCOCK, of Craven Street, in the City of West-
minster, Architect, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN GAS METERS," to be as follows:-
My Invention consists in constructing gas meters as hereafter described..
Inside an outer cylinder or case, closed at all parts except to inlet and outlet
pipes, I fit another concentric cylinder so that a space is left between the two
cylinders; the inner cylinder is soldered or connected at the bottom to the
end of the outer cylinder, while its upper end which reaches to about the
middle of the height of the outer cylinder is open. I admit liquid into the
space between the cylinders. Over the inner cylinder and within the outer
cylinder is a third cylinder acting as a piston; it is of larger diameter than
the inner cylinder, it is closed at the top and open at the bottom, and is free

page_text: to move up and down in the space before mentioned. The space between
the top of this third cylinder and the outer cylinder forms one gas chamber,
while the space within and below the third cylinder forms a second gas
chamber, the two chambers being hermetically sealed from each other by the
liquid in the liquid space. The gas is allowed to enter into each of these
chambers alternately, and its pressure causes the movable cylinder alternately
to rise and fall, the gas contained in the chambers being alternately supplied
to the pipes. The number of up-and-down motions of the movable cylinder
is registered, and the quantity of gas passed through the meter can therefore
be ascertained. The movable cylinder has connected thereto a cord or string
passing through the top of the outer cylinder and over one or more wheels to
a counterweight, to one of which wheels the registering apparatus may be
connected. To prevent escape of gas through the aperture in the outer
cylinder, through which this cord passes, I carry a tube down from this
aperture into another tube in the movable cylinder containing liquid to form
a liquid seal. Instead of cylinders any other convenient shaped cases may
be employed. The meter is fitted with any suitable arrangement for admitting
the gas alternately into. the two chambers.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Willmer Pocock in the Great Seal Patent Office on 2
the 27th July 1866.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
WILLMER POCOCK, of Craven Street, in the City of Westminster, Architect,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-seventh day of January, in the year of our Lord
One thousand eight hundred and sixty-six, in the twenty-ninth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Willmer Pocock, Her special licence that I, the said Williami
Willmer Pocock, my executors, administrators, and assigns, or such others'
as the said William Willmer Pocock, my executors, administrators, and
assigns, should at any time agree 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 GAS METERS," upon the condition (amongst

page_text: others) that I, the said William Willmer Pocock, my executors, or
administrators, by an instrument in writing under my, or their, or one
of their hands and seals, 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 inmediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said William Willmer Pocock, my do hereby.
declare the nature of my said Invention, and in what manner the same
is to be performed, to be particularly described and ascertained in and by the
following statement thereof, reference being had to the Drawings hereunto
annexed, that is to say:
My Invention consists in constructing gas meters as hereafter described.
Inside an outer cylinder or case closed at all parts except to inlet and outlet
pipes I fit another concentric cylinder, so that' a space is left between the two
cylinders; the inner cylinder is soldered or connected at the bottom to the end
of the outer cylinder, while its upper end which reaches to about the middle
of the height of the outer cylinder is open. I admit liquid into the space
between the cylinders. Over the inner cylinder and within the outer cylinder
is a third cylinder acting as a piston'; it is of larger diameter than the inner
cylinder, is closed at the top and open at the bottom, and is free to move up
and down in the space before mentioned. The space between the top of this
third cylinder and the outer cylinder forms one gas chamber, while the space
within and below the third cylinder forms a second gas chamber, the two
chambers being hermetically sealed from each other by the liquid in the liquid
space.
The gas is allowed to enter into each of these chambers alternately,
and its pressure causes the movable cylinder alternately to riso an fall, the
gas contained in the chambers being alternately supplied to the pipes. The
number of up-and-down motions of the movable cylinder is registered and
the quantity of gas passed through the meter can therefore be ascertained.
The movable cylinder has connected thereto a cord or string passing through
the top of the outer cylinder and over one or more wheels to a counterweight,
to one of which wheels the registering apparatus may be connected...To
prevent escape of gas through the aperture in the outer cylinder through
which this cord passes I carry a tube down from this aperture into another
tube in the movable cylinder containing liquid to form a liquid seal. Instead
of cylinders any other convenient shaped cases may be employed. The meter
is fitted with any suitable arrangement for admitting the gas alternately into.
the two chambers..

page_text: Figure 1 of the accompanying Drawings is a vertical section of a gas
meter constructed according to my Invention, Figure 2 is half a horizontal
section, and Figure 8 half a plan of the same.
A, A, A,, A,, is an outer cylinder closed at all parts except to inlet and
outlet pipes as before stated; B, B₁, B, B,, is an inner concentric cylinder
soldered or connected at the bottom to the outer cylinder, that is to say, from
B₁ to B, but it is open at the top from B to B,; I admit liquid into the
annular space between these two cylinders up to a convenient height as shown;
C, C₁, C,, C, is a third cylinder which acts as a piston; it is as before
mentioned of larger diameter than the inner cylinder; it is closed at the top
from C to C, and open at the bottom from C₁ to C, and it is free to move up.
and down in the annular space above mentioned; D, D₁, D₂, D., is a fourth
cylinder connected to the cylinder C, C₁, C₂, C,; this fourth cylinder may
however be dispensed with. The space above C, C,, when the piston
cylinder is down forms one gas chamber, and the space below C, C,, (or below
D₁, D₂, if the fourth cylinder be employed) forms a second gas chamber, and.
as the lower edge C₁, C₂, of the piston cylinder never rises so high as the
surface of the liquid in the annular space the gas cannot pass from one,
chamber to another. S, S₁, is a cord or string connected at one end to the
piston cylinder at S, and carried through the top of the outer cylinder over
two wheels, as shown, to a counterweight W, to which its other end is con-
nected; N, N1, N2, N,, is a tube carried down from the aperture in the outer,
cylinder, through which the cord passes; the lower end of this tube dips into
liquid contained in a larger tube T, T₁, T, T,, in the centre of the piston
cylinder, so that escape of gas through the aperture is prevented. The gas is
allowed to enter the two chambers before mentioned alternately by suitable
inlet pipes, and its pressure causes the piston cylinder alternately to rise and
fall, the gas contained in the two chambers being alternately supplied through
suitable outlets to the pipes. The number of up-and-down motions of the
piston cylinder is registered by apparatus connected either to one of the wheels
above mentioned or to other convenient part, and the quantity of gas passed
through the meter thereby ascertained. The gas inlets and outlets may
be arranged as seen in Figures 4, 5, and 6, or in any other convenient
manner.
Figure 4 is a plan; Figure 5 a section, one half through A, B, and the
other half through C, D, of Figure 6, and Figure 6 is a vertical section of
what may be termed a double gas meter, that is to say, two gas meters con-
structed as before described and placed side by side, so that the piston of one
meter is in full work while that of the other meter is reversing its movement,

page_text: In these Figures instead of the parts being cylindrical they are of the forms
shown, but any other convenient form may be adopted. P, P₁, P, P. and
P P P P are the two pistons which are free to move up and down when
acted upon by the gas as before explained.
The inner cases are in the arrangement shewn open at the bottom from
B to B and from 6 to 6', and are fitted with a top or cover C, C¹, and c, c¹.
S, S1, S2, and 3, 81, 82, are the cords or strings connected to the pistons carried
over wheels as shewn, and attached at their other ends to counterweights W
and w, which are in this instance placed
tubes through which the cords S and
these tubes are supplied with liquid to
is the crank connecting the pistons P and p with the valves which are
contained in the box X. a, a, are unions or sockets to receive pipes, one of
which is the inlet and the other the ontlet pipe for the gas.
within the inner case; T, T, are half
are carried to the counterweights;
prevent escape of gas; K, Figure 4,
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that I claim constructing gas
meters in which a piston is arranged and acts substantially as herein-before
described and represented in the accompanying Drawings, the lower end
of such piston being immersed in liquid, as and for the purpose described.
In witness whereof, I, the said William Willmer Pocock, have hereunto
set my hand and seal, this Twentieth day of July, One thousand eight
hundred and sixty-six.
WN. WILLMER POCOCK. (LS.)