IMPROVEMENTS IN GAUGES FOR SHEWING THE WATER LEVEL IN STEAM BOILERS AND FOR OTHER LIKE USES
Year: 1880

page_text: LETTERS PATENT to John Dewrance, of 176, Great Dover Street, Borough, in
the County of Surrey, for an Invention of "IMPROVEMENTS IN GAUGES FOR
SHEWING THE WATER LEVEL IN STEAM BOILERS AND FOR OTHER LIKE USES."
PROVISIONAL SPECIFICATION left by the said John Dewrance at the Office
of the Commissioners of Patents on the 14th January 1880.
JOHN DEWRANCE, of 176, Great Dover Street, Borough, in the County of Surrey.
"IMPROVEMENTS IN GAUGES FOR SHEWING THE WATER LEVEL IN STEAM BOILERS
AND FOR OTHER LIKE USES."
This Invention has for its object improvements in gauges for shewing the water
level in steam boilers and for other like uses.
In the water gauges commonly in use the water level is shewn in a glass tube.
This tube is found in practice to be very liable to fracture, which renders the gauge
useless. Besides it is necessary to provide stop cocks by which the connection
with the boiler may be immediately shut off when fracture of the glass occurs.
My improved gauge consists of a metal tube open at the front and adapted to
receive a strip of stout plate glass. This open tube is cast with passages and
flanged connections at its ends for the purpose of making direct connection with
the boiler at the top and bottom of the tube. It is not necessary to provide stop
cocks between the gauge and the boiler, for they are not required when a flat glass
is used, applied in the peculiar manner which I shall describe. In such gauge a
breakage such as to permit water to escape never occurs. The edges of the opening
in the metal tube are made of considerable thickness, and they are grooved to
receive a narrow strip several inches long cut from stout plate glass. The glass
slides end wise into the grooves; it is able to enter freely between the lips or con-
trolling edges of the grooves, so that there is no risk of the metal binding on the
glass. Within the lips the groove is enlarged into a cavity to receive packing, thus
permitting the packing to overlap the edges of the glass strip. The packing I
employ is asbestos, and the process of packing is as follows:-Before the glass is
inserted a small quantity of the packing is pressed evenly into the further end o
the groove to form a bed for the end of the glass to abut upon. The glass being
then put in is held in place by means of a firm pressure maintained upon it at the
further end. Also a temporary filling piece is inserted along one edge of the strip

page_text: of glass; it fills the cavity of the groove, so that the glass may not shift during the
process of packing the groove on the other side. The packing material is inserted
into the groove little by little, and is condensed by pressure with a tool which is
able to pass down within the cavity. The groove being thus filled the edges of the
glass become thoroughly embedded in the packing. When the packing of one side
is completed the filling strip is withdrawn and the groove on the other side is
packed in a similar manner. Lastly a small bed of packing is laid over the upper
or outer end of the glass and a covering strip of metal is laid on the packing, it
just enters the outer end of the groove. The groove terminates within a socket
formed at the top of the gauge, and a screw plug being inserted into the socket and
screwed up keeps everything in its place. I provide a blow off cock at the lower
end of the gauge, as usual; I employ an asbestos packed cock for this purpose.
Two glasses may be used if desired.
In order that the water line may be more easily seen a white or reflecting surface
can with advantage be placed behind the glass.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John Dewrance in the Great Seal Patent Office on the 14th July
1880.
JOHN DEWRANCE, of 176, Great Dover Street, Borough, in the County of Surrey.
"IMPROVEMENTS IN GAUGES FOR SHEWING THE WATER LEVEL IN STEAM BOILERS
AND FOR OTHER LIKE USES."
This Invention has for its object improvements in gauges for shewing the water
level in steam boilers and for other like uses.
In the water gauges commonly in use the water level is shown in a glass tube.
This tube is found in practice to be very liable to fracture, which renders the gauge
useless. Besides, it is necessary to provide stop cocks by which the connection with
the boiler may immediately shut off when fracture of the glass occurs. My improved
gauge consists of a metal tube open at the front and adapted to receive a strip of
stout plate glass. This open tube is cast with passages and flanged connections at
its ends for the purpose of making direct connection with the boiler at the top and
bottom of the tube. It is not necessary to provide stop cocks between the gauge
and the boiler, for they are not required when a flat glass is used applied in the
peculiar manner which I shall describe. In such gauge a breakage such as to permit
water to escape never occurs. The edges of the opening in the metal tube are made
of considerable thickness, and they are grooved to receive a narrow strip several
several inches long cut from stout plate glass. The glass slides endwise into the
grooves; it is able to enter freely between the lips or controlling edges of the grooves,
so that there is no risk of the metal binding on the glass. Within the lips the
groove is enlarged into a cavity to receive packing, thus permitting the packing to
overlap the edges of the glass strip. The packing I employ is asbestos, and the
process of packing is as follows:-Before the glass is inserted a small quantity of
the packing is pressed evenly into the further end of the groove to form a bed for
the end of the glass to abut upon. The glass being then put in is held in place by
means of a firm pressure maintained upon it at the end. Also a temporary filling
piece is inserted along one edge of the strip of glass; it fills the cavity of the groove,
so that the glass may not shift during the process of packing the groove on the
other side. The packing material is inserted into the groove little by little and is
condensed by pressure with a tool which is able to pass down within the cavity.
The groove being thus filled the edges of the glass become thoroughly embedded in
the packing.
It is convenient to employ packing tools of such a form that they also serve as
filling pieces; two such tools are used, one on either side. A short length of one groove
is packed and the tool is left in its place whilst a similar length is packed in the
groove on the other side, and so on alternately. Lastly a small bed of packing is
laid over the upper or outer end of the glass and a covering strip of metal is laid on
the packing, it just enters the outer end of the groove. The groove terminates
within a socket formed at the top of the guage, and a screw plug being inserted into
the socket and screwed up keeps everything in its place. I provide a blow off cock
at the lower end of the gauge as usual. I employ an asbestos packed cock for this
purpose; two glasses may be used if desired.
In order that the water line may be more easily seen a white or reflecting surface
can with advantage be placed behind the glass.
In order that my said Invention may be most fully understood and readily carried
into effect, I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figure 1 is a front elevation, and Figure 2 is a vertical section of a water gauge
constructed according to my Invention; this gauge is not provided with cocks for
cutting off communication with the boiler, and it is a feature of my Invention that

page_text: such cocks are not required in consequence of the great safety from breakage of
these gauges having flat glasses packed in the manner described; nevertheless as
shut off cocks may be employed, and perhaps will be demanded by some users of
gauges, I also represent by the Figures 3, 4, 5, and 6, a gauge so provided; Figure 3
is a front elevation; Figure 4 is a vertical section: Figure 5 is a transverse section,
and Figure 6 is a plan of such a gauge. a is a brass casting in the form of an
open tube or chamber open in front; a', a¹, are connecting passages at the top and
bottom forming two communications with the interior of the boiler or vessel, the
water level within which the gauge is to indicate, As is usual with water gauges
one of the passages a¹ opens into the boiler or vessel at some distance below the
water line and the other above it; indeed the upper passage is continued by means
of a copper pipe b within the boiler, so that only steam may enter by this passage.
Around the passages a', a', flanges are formed for bolting to the exterior of the
boiler; c is the flat glass with which the opening or window in the front of the
chamber a is glazed. The way in which the grooves for receiving the glass are
formed is clearly indicated by the sectional views; the side grooves all are enlarged,
as is seen in Figure 5, so that the packing may overlap the edges of the glass. The
packing material which I employ is asbestos in a finely divided fibrous state firmly
pressed together. The method of packing has already been fully described;
d is a
covering strip of metal which is laid upon the top of the packing, and e is a screw
plug entering a socket provided to receive it upon the chamber a and serving to
keep the packing in place; f is a strip of enamelled metal or porcelain screwed
against the back of the chamber a to render the water line more easily visible;
g is a screw plug opposite the lower passage a¹, by removing the plug the passage
can readily be reached to remove an obstruction; h is the blow off cock, and in
Figures 3, 4, and 5, i, i, are cocks for shutting off the communication with the
boiler.
Having thus described the nature of my said Invention and the manner of
performing the same, I would have it understood that I claim,-
First. My improved water gauge for sbewing the water level in steam boilers
and for other like uses, and which consists of an open tube or chamber a having
connections a¹, a¹, at its upper and lower ends by which to communicate with the
boiler or other vessel in which the water level is to be ascertained; and haying also
a window in front glazed with a flat glass c, which is packed around its edges with
packing applied substantially as herein described.
Second. The method of forming the packing cavities al illustrated by Figure 5,
so that the packing may overlap the edges of the glass, whereby the risk of
fracture there would be if the packing were at the edges only of the glass is
avoided.
Third. My improved asbestos packed gauges, substantially as described and
represented in the annexed Drawings.
In witness whereof, I, the said John Dewrance, have hereunto set my hand
and seal, this Twelfth day of July, in the year of our Lord One thousand
eight hundred and eighty.
JOHN DEWRANCE. (L.S.)