A NEW AND IMPROVED DRY PRESSURE GAUGE
Year: 1884

page_text: I, THOMAS THORP of Whitefield in the County of Lancaster, Architect do hereby
declare the nature of my invention for A NEW AND IMPROVED DRY PRESSURE
GAUGE to be as follows:-
This Invention relates to gas pressure gauges and the object of the Invention is
to obtain the pressure at which the gas exists without recourse to water or other
liquid now used in ordinary pressure ganges.
The apparatus consists of a tube, a portion of the lower half of which is cut away,
the interior of the upper half being bored or otherwise made slightly taper the
widest part being at the top. A glass tube is fitted airtight in the lower part of
the tube where cut away and at the ends of the tube caps are fitted, the cap at the
lower end having a nipple for attachment to the gas supply the upper cap having
a small perforation through which the gas escapes.
In the taper portion of the tube is loosely fitted a thin metallic or other suitable
disc to which is fastened a slender rod having a disc or pointer of a smaller
diameter than the glass tube, in which it works, attached to it.
Or, instead of a taper tube a perfectly cylindrical tube may be used (or this tube
may be slightly taper also) having a narrow slit cut its whole length in which
works one or more discs or their equivalents carrying a pointer projecting through
the slit.
This alit tube is enclosed in another tube so cut away, but made air-tight by
the opening being covered with glass, as to show the pointer projecting thro
the slit
When the apparatus is connected with the gas supply & in action, the flow of
gas (which varies with the pressure) through the small perforation in the upper
cap causes the disc carrying the pointer to rise & indicate on a scale previously
marked from a standard gauge, the pressure required.

page_text: I, THOMAS THORP of Whitefield in the County of Lancaster Architect do hereby
declare the nature of my invention for A NEW AND IMPROVED DRY PRESSURE
GAUGE and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement :—
This Invention relates to Gas pressure gauges and the object of the Invention is
to obtain the pressure at which the gas exists without having recourse to water or
other liquid now used in ordinary pressure gauges.
The apparatus consists of a tube, a portion of the lower half of which is cut away,
the interior of the upper half being bored or otherwise made slightly taper the
widest part being at the top. A glass tube is fitted airtight in the lower part of
the tube where cut away & at the ends of the tube caps are fitted, the cap at the
lower end having a nipple for attachment to the gas supply the upper cap having
a small perforation through which the gas escapes.
In the taper portion of the tube is loosely fitted a thin metallic or other suitable
disc, somewhat smaller than the narrowest part of the taper tube, to this disc is
suspended a slender rod having a disc or pointer of a smaller diameter than the
glass tube in which it works, attached to it.
Or, instead of a taper tube, a perfectly parallel cylindrical tube may be used (or
this tube may be slightly taper also) having a narrow slit cut its whole length, in
which works one or more discs or their equivalents carrying a pointer projecting
through the slit. This slit tube is enclosed in another tube so cut away but made
air tight by the opening being covered with glass, as to show the pointer through
the slit in a manner perfectly well known in an apparatus at present in use for
testing the comsumption of gas.
When the apparatus is connected with the gas supply and in action the flow of
Gas, which varies with the pressure, through the small perforation in the upper cap
causes the disc carrying the rod and pointer to rise and indicate on a scale
previously marked from a standard gauge the pressure required.
And in order that my Invention may be understood and readily carried into
effect, I will proceed to describe the accompanying sheet of drawings, reference
being had to the figures and letters thereon marked, similar letters referring to
similar parts throughout the several views.
Fig. 1. is a sectional elevation, Fig. 2. an elevation, and Fig. 3. a plan through A A,
of my improved dry pressure gauge.
In figures 1. 2 & 3. a is a metal tube in which is preferably fitted another and
smaller tube b, c is a glass tube fitted airtight between the taper tube b and the
cap d, e and e¹ are washers of yielding material between which the glass tube c
is pressed, fis a small perforation in the cap g which can be removed from the
nipple g¹ when it is desired to use the apparatus for any other purpose as for
instance the testing of burners, h is a thin metallic or other suitable disc attached to
the rod i to which the disc or pointer k, preferably of ebonite is fitted, 7 is the scale
marked from a standard pressure gauge but the figures marked are not to be taken
as the extent of the capability of the apparatus which manifestly varies with the

page_text: taper of the tube b and the weight and size of the discs h and k and rod i.
Plaster of Paris is preferably run between the glass tube and the tube a.
0
Having now particularly described and ascertained the nature of my said
Invention, and in what manner the same is to be performed, I declare that what
I claim is
1. The combination of the perforation f, taper tube b, discs h and k, rod i and
scale 7, as and for the purposes herein shown and described.
2. The application of the cap g having perforation f to apparatus, at present in
use for testing the consumption of gas, having parallel tube and narrow slit in
lieu of the taper tube b, as and for the purposes herein shown and described.