AN IMPROVED STRAM AND VACUUM GAUGE
Year: 1867

page_text: LETTERS PATENT to George Davies, of No. 1, Serle Street, Lincoln's Inn,
in the County of Middlesex, and No. 87, St. Vincent Street, in the City
of Glasgow, Civil Engineer and Patent Agent, for the Invention of
"AN IMPROVED STRAM AND VACUUM GAUGE."-A communication from
abroad by Emmett Quinn, of Washington, Columbia, in the United
States of America.
Sealed the 27th August 1867, and dated the 26th March 1867.
PROVISIONAL SPECIFICATION left by the said George Davies at the
Office of the Commissioners of Patents, with his Petition, on the
26th March 1867.
I, GEORGE DAVIES, of No. 1, Serle Street, Lincoln's Inn, in the County of
Middlesex, and No. 87, St. Vincent Street, in the City of Glasgow, Civil
Engineer and Patent Agent, do hereby declare the nature of the said
Invention for "AN IMPROVED STEAM AND VACUUM GAUGE," (a communication
to me.. from abroad by Emmett Quinn, of Washington, Columbia, in the
United States of America,) to be as follows:-
This gauge is composed of a number of vertical tubes arranged in rows as
close as practicable to each other, the ends of all being inserted in plates of
the proper dimensions, one at the top and the other at the bottom. On the.-

page_text: outside or face of each plate are cut channels or grooves, beginning at the
bottom between the first and second tube, then at the top between the
second and third, and so on alternately through the whole series. The faces of
these tube plates with their channels are covered with another plate or cap
firmly secured thereto, rendering the channels perfectly tight, the whole
constituting what may be termed a compound siphon, the two outer or end
tubes of which are open at top. All the lower halves of the tubes are filled
with mercury, and the upper halves, except of the two outer or end tubes, are
filled with fluid of a less specific gravity. To the first tube in the series is
attached the tube through which steam or other pressure is intended to be
communicated, and the last is a compound one, the lower portion being iron,
the upper half or index tube being formed of a back piece of hard wood,
vulcanite, or other suitable material, with a wide shallow longitudinal
channel or groove of a little less calibre than the other tubes in its front
covered with plate glass, and all cemented and clamped firmly together;
between this and the lower or iron portion, and attached to and communicating
with both, is an elastic reservoir capable of expansion and contraction for the
purpose of raising or lowering the surface of the mercury to the zero point of
the scale when caused to vary therefrom by changes of temperature., The
tubes are always so arranged that the last or index tube is in the middle of
the front of the series, and shows its glass face between the scales or index
plates of the gauge. There are also elastic diaphragms actuated by screws
for controlling the movements of the fluids, to prevent those in one tube from
mingling with those in another, as well as from escaping from the end tubes
whilst the gauge is being transferred or handled, and without which the
accuracy and usefulness of the instrument would be in constant danger
of being destroyed.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by. the said George Davies in the Great Seal Patent Office on the
26th September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
DAVIES, of No. 1, Serle Street, Lincoln's Inn, in the County of Middlesex,
and No. 87, Saint Vincent Street, in the City of Glasgow, Civil Engineer and
Patent Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of March, in the year of our Lord

page_text: One thousand eight hundred and sixty-seven, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said George Davies, Her special licence that I, the said George
Davies, my executors, administrators, and assigns, or such others as I, the said
George Davies, 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 STEAM
AND VACUUM GAUGE," a communication to me from abroad by Emmett
Quinn, of Washington, Columbia, in the United States of America, upon
the condition (amongst others) that I, the said George Davies, my exe-.
cutors 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 immediately after the date of the said Letters
Patent.
NOW KNOW YE, that I, the said George Davies, 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 in writing, and on reference to the accompanying Sheet of
Drawings, that is to say :-
This gauge is composed of a number of vertical tubes arranged in rows as
close as practicable to each other, the ends of all being inserted in plates of
the proper dimensions, one at the top and the other at the bottom. On the
outside or face of each plate are cut channels or grooves, beginning at the
bottom between the first and second tube, then at top between the second and
third, and so on alternately through the whole series. The faces of these tube
plates with their channels are covered with another plate or cap firmly secured
thereto, rendering the channels perfectly tight, the whole constituting what
may be termed a compound syphon, the two outer or end tubes of which are
open at top. All the lower halves of the tubes are filled with mercury, and
the upper halves, except of the two outer or end tubes, are filled with fluid of
a less specific gravity. To the first tube in the series is attached the tube
through which steam or other pressure is intended to be communicated, and
the last is a compound one, the lower portion being iron, the upper half or
index tube being formed of a back piece of hard wood, vulcanite, or other
suitable material, with a wide, shallow, longitudinal channel or groove (of a

page_text: little less calibre than. the other. tubes) in its front covered with plate glass,
and all:cemented and clamped firmly together; between. this and, the lower
or iron portion, and attached to and communicating with both, is an elastic
reservoir. capable of expansion and contraction for the purpose of raising.or
lowering the surface of the mercury to the zero point of the scale when caused
to vary. therefrom by changes of temperature. The tubes are always, so
arranged that the last or index. tube is in. the middle of the-front, of the series,
and shows its glass face. between the scales, or index plates of the gauge.
There are also. elastic diaphragms actuated: by, screws, for. controlling the
movements of the fluids, to prevent those in one tube from: mingling, with
those in another, as well as from escaping from the end tubes whilst the gauge
is being transferred or handled, and without which the accuracy and usefulness.
of the instrument would be in constant danger of being destroyed.
Such being the nature and object of the said. Invention for "An Improved.
Steam and Vacuum Gauge," I will now proceed to describe more in detail
the manner in which the same is to be or may be performed; or carried into
practical effect; and in order that the same may, be distinctly understood. I
have annexed hereunto a Sheet of Drawings illustrative thereof, and have
marked the same with figures and letters of reference corresponding with those
in the following explanation, that is to say:
The construction and operation of the instrument will be better understood,
by reference to the annexed. Drawings, in which the same letters, indicate,
corresponding parts in the different Drawings.
Figures 1 and 2 are sectional elevations of the gauge; Figures, 3 and 4, are
top and bottom views of the top and bottom tube. plates respectively, shewing.
the position and arrangement of the channels or grooves in each; Figure 5,
transverse section of the index. tube near to where it joins, the reservoir;
Figure:6, a face.view of the same.end; Figure 7; a face view. of the case of
the instrument.
A, A, A, Figure 1, are the tubes; B, B, the tube plates; and C, C, the
auter or. cap.plates with the packing b, b; between them; the portions of this
packing. over the channels or passages between the tubes, serve as elastic
diaphragms by. which to close said, channels by tightening the screws d,.d,
upon the plates e, e, which force the plungers f, f, against the diaphragms,
causing the latter to, sink, into and close the channels c, c.
The plate e
Figure 2, at top also presses the elastic cushion m upon the top of the index
plate and closes it, when communication is severed between the other tubes.
By dispensing with the packing and making the channels in the face of the
outer, plates and causing said, plates to slide upon the others, as in the case of

page_text: The
ordinary slide valves, the communication between the tubes may be severed,
but this is not considered practicable on account of the difficulty of making
and keeping them perfectly tight, which would be absolutely necessary.
elastic reservoir D, between the lower section A and the index tube E, is of
india-rubber tubing, sufficiently elastic to expand' and contract to the requisite
extent. Instead of an elastic tube a metallic reservoir of any convenient size
and shape with a flexible diaphragm, against which the pressure screw p can
operate, might be employed; but as the pressure in the reservoir is never over
eight or ten pounds to the square inch an india-rubber tube is sufficiently
strong and durable; it is of slightly greater calibre, than. the others;. which
confine it on three sides; and by Compressing or relieving it by means of the
set screw p and the pressure plate r the mercury is: raised tor: lowered to the
zero point of the scale.. The same result may be obtained by making
the scale n to slide up or down, or by raising or lowering the index tube.
The Figures 5 and 6 are views, of sections of the tube E, shewing the
wooden or vulcanite back; the glass. face n, the clamps o, and the channel or
groove i.
A gauge constructed substantially the same as the within described, but
with some modifications and improvements, answers admirably as a vacuum
gauge, but as the Inventor intends making a separate application for Letters
Patent for such modifications and improvements no description thereof will
herein be given.
Having now described the nature and object of the said Invention for "An
Improved Steam and Vacuum Gauge," together with the manner in which
the same is to be or may be performed or carried into practical effect, I would
remark, in conclusion, that I claim as the Invention communicated to me by
the above-named Emmett Quinn,―
Firstly, the tubes inserted in plates, as described, with the channels eut
therein from one tube to another, and with a cap or outer plate covering the
channels and ends of the tubes, as and for the purpose described.
Secondly, the packing and diaphragms between the plates with the
plungers for the purpose of cutting off communication between the tubes, as
described.
Thirdly, adjusting the mercury in the final or index tube to the zero point
on the scale in the manner described.
Fourthly, constructing the index tube by a combination of a back piece
containing a groove of a suitable calibre with a glass face cemented to or
clamped thereon in a manner substantially as described.

page_text: Fifthly, the channels between the tubes when the same are contracted,
substantially as and for the purpose described.
Sixthly, a series of tubes arranged to communicate with each other,
substantially as described, in combination with cocks or devices, whereby the
communication between the tubes may be closed for the purpose specified.
And, seventhly, the combination of the said tubes and the within-described
plates, or their equivalents, which may be so adjusted as to cover the tops of
the tubes, or may be detached to permit the fluids to be introduced into the
tubes.
In witness whereof, I, the said George Davies, have hereunto set my
band and seal, this Twenty-sixth day of September, in the year of
our Lord One thousand eight hundred and sixty-seven.
GEORGE DAVIES. (L.B.)