AN IMPROVED GAS TESTING COCK
Year: 1875

page_text: LETTERS PATENT to William Thomas Walker, of Highgate, in the
County of Middlesex, for the Invention of "AN IMPROVED GAS
TESTING COCK."-A communication from abroad by John Frederick
Theodore Drory, of Lille, in the Republic of France.
PROVISIONAL SPECIFICATION left by the said William Thomas
Walker at the Office of the Commissioners of Patents, with his
Petition, on the 30th September 1875.
I, WILLIAM THOMAS WALKER, of Highgate, in the County of Mid-
dlesex, do hereby declare the nature of the said Invention for "An
IMPROVED GAS TESTING COCK," to be as follows, that is to say :—
The Invention communicated to me consists in the construction of an
improved gas testing cock for use in gas works for ascertaining the
temperature of the gas and for detecting its impurities at any part of
the works, and in the principal main or apparatus in a more perfect and
simple manner than hitherto, and without escape of gas,

page_text: The improved gas testing cock is constructed of an outer envelope,
consisting of a conical brass tube closed at one end and open at the
other end. The open end of the tube is formed with a flange and a
screw thread for the purpose herein-after described. Two apertures of
suitable dimensions are formed in the tube, such apertures, which are
directly opposite each other, serving for the admission of the gas into
the cock. In the outer envelope fits gas-tight an inner moveable
envelope or slide of brass, having apertures corresponding with those in
the outer envelope. One end of the slide is open for the introduction
of the tester herein-after described, and the other end is closed. At the:
closed end is a hitch or stop working in a transverse slot in the outer
envelope, which allows of the slide being turned so as to open or close
the apertures in the outer envelope; thus the slide only serves to admit
or shut off the gas.
The tester consists of an ordinary thermometer, on the side of which
a spring is fixed for receiving and holding a piece of testing paper. The
thermometer is fixed to a conical plug and handle, so that when the
tester is introduced into the slide the said conical plug shuts it gas-
tight. The tester is made secure by means of a hitch or stop in the
conical plug working in a bayonet joint slot.
To use this improved testing cock a hole (corresponding in size with
the tapped part of the outer envelope) is bored in the principal main
and tapped, and into this hole the outer envelope of the cock is screwed
tight up against the herein-before described flange thereon, the inner
envelope being in the position necessary to close the apertures in the
outer envelope. If the tester be now introduced into the cock and
turned to the right by means of its handle, so as to open the apertures
of the two envelopes, the gas passing through the main will at the same
time pass through the cock and over the testing paper and thermometer;
by being then turned to the left the apertures of the envelopes will be
closed, and the tester can be withdrawn without escape of gas; the
degree on the thermometer can then be read off, and the color of the
testing paper examined.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Thomas Walker in the Great Seal Patent
Office on the 29th March 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
THOMAS WALKER, of Highgate, in the County of Middlesex, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirtieth day of September, in
the year of our Lord One thousand eight hundred and seventy-five, in
the thirty-ninth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said William Thomas Walker,
Her special licence, that I, the said William Thomas Walker, my
executors, administrators, and assigns, or such others as I, the said
William Thomas Walker, 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 "An Improved GAS TESTING Cocx,” a com-
munication to me from abroad by John Frederick Theodore Drory, of
Lille, in the Republic of France, upon the condition (amongst others)
that I, the said William Thomas Walker, 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 Invontion, 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 William Thomas Walker, do
hereby declare the nature of the said Invention, and in what manner
the same is to be performed, to be particularly described and ascertained
in and by the following statement, reference being had to the Drawing
hcreto annexed, and to the figures and letters marked thereon, that is to
say :-
The Invention communicated to me consists in the construction of an

page_text: temperature of the gas and for detecting its impurities at any part of
the works, and in the principal mains or apparatus in a more perfect and
simple manner than hitherto, and without escape of gas.
Gas testing cocks as hitherto employed have been constructed of a
pocket or envelope formed with a flange or rim and screw thread at ono
end, by which it is screwed into a corresponding hole in the principal
main. Into this pocket or envelope was placed a thermometer fitted to
a conical plug and handle, but as no means were provided to allow of
the gas coming into contact with the thermometer the temperature of
the gas could not be correctly ascertained, and this construction of cock
did not admit of testing the quality or degree of purity of the gas.
According to this Invention the improved gas testing cock is con-
structed as hitherto of an outer envelope or pocket, consisting of a tube
of iron, brass, or other metal or alloy closed at one end and open at the
other end, and formed with a flange or rim and a screw thread, but I 1
make the pocket of a conical shape, and form two apertures of suitable
dimensions therein, such apertures, which are directly opposite each
other, serving for the admission of the gas into the cock. In the outer
envelope I fit, so as to work gas-tight, an inner moveable envelope or
slide of iron, brass, or other suitable metal or alloy, having apertures 2
corresponding with those in the outer envelope or pocket. One end of
the slide or plug is open for the introduction of the tester herein-after
described, and the other end may be open or closed. At the lower end
is a hitch or stop working in a transverse slot in the outer envelope or
pocket, which allows of the slide or plug being turned, so as to open or 2
close the apertures in the outer envelope or pocket; this slide or plug
has for object to admit or shut off the gas.
The tester consists of an ordinary thermometer fixed to a conical
plug and handle as usual, so that when the tester is introduced into the
slide or plug the said conical plug shuts it gas-tight. On the side or 3
other suitable part of the thermometer I fix a metal spring for receiving
and holding a piece of test paper or other testing material, and tho
tester is made secure by means of a hitch or stop in the conical plug
working in a bayonet joint slot.
To make the Invention communicated to me better understood I will 8
now proceed to describe the same by reference to the accompanying
Drawing, in which Figure 1 is a front clovation of the improved gas

page_text: testing cock drawn full size, the cock being shewn closed; Figure 2
is a detached view of the slide or plug; and Figure 3 is a detached view
of the tester.
Similar letters in all the Figures represent similar parts.
a is the outer envelope or pocket formed of a conical shape as shewn,
and closed at the lower end; b is the flange or rim, and c, the screw
thread of the same; d is one of the apertures of the pocket for the
admission of the gas; and e is the inner envelope or plug formed with
apertures corresponding with the apertures in the pocket a; is the
hitch or stop of the slide working in the transverse slot in the pocket;
i is the thermometer of the tester shewn in Figure 3; j is the conical
plug, to which the thermometer is fixed, such plug fitting gas-tight in
the slide e; is the handle; and is the spring fixed to the side (or
other suitable part) of the thermometer; m is the hitch or stop in the
plugj; and ⁄ is the bayonet joint slot in the upper end of the slide or
plug e.
To use this improved testing cock a hole (corresponding in size with
the tapped part of the outer envelope) is bored in the principal main,
and tapped as heretofore, and into this hole the outer envelope a of the
cock is screwed tight up against the herein-before described flange or
rim 6 thereon, the inner envelope or plug e being in the position
necessary to close the apertures d in the outer envelope a, as shewn in
Figure 1. If the tester shewn on Figure 3 be now introduced into the
cock and placed in the position shown in Figure 1 it will be understood
that by turning the same to the right by means of its handle k the slide
or plug e will be turned, and the apertures & and f of the two envelopes a
and e respectively will be brought opposite one another, and the cock
will be opened. The gas passing through the main will thus be allowed
to pass through the cock, and will come in contact with the thermometer
and the testing paper or other testing material. If the handle & be now
turned to the left the apertures of the envelopes a and e will be closed,
and the tester can be withdrawn without escape of gas. The degree on
the thermometer can then be read off, and the color of the testing paper
or other testing material be examined.
Having thus described the Invention communicated to me, and the
best means with which I am acquainted for carrying the same into
effect, I wish it to be understood that what is claimed and intended to

page_text: be protected by the herein-before in part recited Letters Patent is, the
improved gas testing cock constructed and operating substantially as
herein-before described and represented in the accompanying Drawing.
In witness whereof, I, the said William Thomas Walker, have
hereunto set my hand and seal, this Twenty-eighth day of March, t
in the year of our Lord One thousand eight hundred and
seventy-six.
Witness,
G. F. REDFERN,
4, South Street,
Finsbury,
E.C.
WILLIAM THOMAS WALKER. (L.S.)