IMPROVEMENTS IN SAFETY ATTACHMENTS FOR STEAM GENERATORS
Year: 1870

page_text: LETTERS PATENT to Benjamin Joseph Barnard Mills, of 35, Southampton
Buildings, in the County of Middlesex, Patent Agent, for the
Invention of "IMPROVEMENTS IN SAFETY ATTACHMENTS FOR STEAM
GENERATORS." -A communication from abroad by Hiram Kimball,
of Randolph, in the County of Orange, and State of Vermont, United
States of America, Mechanical Engineer.
1
Sealed the 9th August 1870 and dated the 27th May 1870.
COMPLETE SPECIFICATION filed by the said Benjamin Joseph Barnard
Mills at the Office of the Commissioners of Patents, with his Petition
and Declaration, on the 27th May 1870, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
5 TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BENJAMIN
JOSEPH BARNARD MILLS, of 35, Southampton Buildings, in the County
of Middlesex, Patent Agent, send greeting.
WHEREAS I am in possession of an Invention for "IMPROVEMENTS IN
SAFETY ATTACHMENTS FOR STEAM GENERATORS," and have petitioned Her
and Declaration, on the 27th May 1870, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, BENJAMIN
JOSEPH BARNARD MILLS, of 35, Southampton Buildings, in the County
of Middlesex, Patent Agent, send greeting.

page_text: Majesty to grant unto me, my executors, administrators, and assigns,
Her Royal Letters Patent for the same, and have made solemn Declaration
that it has been communicated to me from abroad by Hiram Kimball,
of Randolph, in the County of Orange, and State of Vermont, United
States of America, Mechanical Engineer.
NOW KNOW YE, that I, the said Benjamin Joseph Barnard Mills,
do hereby declare that the following Complete Specification, under my
hand and seal, fully describes and ascertains the nature of the said
Invention, and in what manner the same is to be performed, in and
by the following statement thereof, that is to say :—
The Invention relates in part to improvements on an Invention for
which Letters Patent were granted to me, dated June 2nd, 1869, No. 1701,
which consists essentially of a water chamber or reservoir located
externally of the boiler above the water line, and communicating with
the interior of the boiler through a pipe at the lowest level to which the
water in the boiler is desired to fall before an alarm is sounded. The
elevated chamber contains a buoy, to the upper part of which is attached
a valve closing a port communicating with the atmosphere, so that so
long as the water in the boiler is at a proper height, the pressure of
steam keeping the clevated chamber or reservoir full of water will cause
the valve to be pressed against its seat, but the instant the water descends
below the mouth of the pipe leading from the reservoir into the boiler
the water will run from the elevated reservoir, its place being supplied
with steam and permitting the buoy to descend by its gravity so that
the port will be opened and steam discharged therethrough, sounding
a whistle or other alarm until the boiler receives a proper supply of

page_text: Figure 1 is a vertical longitudinal section of the improved apparatus;
Figure 2 is a horizontal section on the line w, w, Figure 1; Figure 3 is
a vertical section on the line x, x, Figure 1; Figure 4 is a horizontal
section on the line y, y, Figures 1 and 3; Figure 5 is a horizontal section
at z, z, Figures 1 and 3; Figure 6 is an axial section of the valve
chamber shewing the valve partly in section and illustrating the manner
of grinding it into its seat.
The elevated reservoir A, buoy B, valve E, connection II, and whistle
are employed as before referred to, but according to the present Invention
the upper part of said elevated reservoir A is connected with the steam
dome or any part of the boiler, which being above the water level is
always occupied by steam, by means of a small pipe F provided with a
stop cock or valve I which ordinarily remains closed.
Now it will be readily seen that on the stop cock or valve I being
opened steam will enter the upper part of the reservoir, produce an
equilibrium of pressure and allow the water in the reservoir to fall to
the same level as in the boiler, and produce the same action of the buoy B
and valve E as though the water in the boiler had fallen so low as to
allow the elevated reservoir to be filled with steam through the main
pipe H. This device thus affords an almost instantaneous test of the
action of the indicator.
The pipe F serves not only as a test pipe but also to keep the indicator
in order by allowing the water in the elevated reservoir to fall quickly
and, if necessary, frequently, whereby any scale or other refuse which
might otherwise lodge in the indicator will be washed out, and in case of
anything lodging between the valve E and seat S so as to prevent the
valve E from closing, by opening the "test pipe" F, the valve E will be
caused to fall and thereby allow the impediment to drop or pass out with
the steam, whereas without the "test pipe" this action can only be
produced by allowing the water in the boiler to fall below the mouth
of the pipe H.

page_text: Third. The removable valve chamber Q constructed and arranged to
admit of grinding of the valve into its seat, substantially as herein set
forth.
In witness whereof, I, the said Benjamin Joseph Barnard Mills,
have hereunto set my hand and seal, this Twenty-seventh day of
May, in the year of our Lord One thousand eight hundred and
seventy.