IMPROVEMENTS RECORDING THE AMOUNT OF SALT IN FOR INDICATING AND RECORDING THE PRESSURE FOR OTHER PURPOSES IN APPARATUS FOR INDICATING AND THE WATER OF STEAM BOILERS AND DENSITY OF SOLUTIONS BOILING UNDER PROVISIONAL SPECIFICATION
Year: 1882

page_text: LETTERS PATENT to The Honorable John William Plunkett of Dunstall Priory
in the County of Kent and of Park Square in the County of Middlesex for
an Invention of "IMPROVEMENTS
RECORDING THE AMOUNT OF SALT IN
FOR INDICATING AND RECORDING THE
PRESSURE FOR OTHER PURPOSES
IN APPARATUS FOR INDICATING AND
THE WATER OF STEAM BOILERS AND
DENSITY OF SOLUTIONS BOILING UNDER
PROVISIONAL SPECIFICATION left by the said John William Plunkett at
the Office of the Commissioners of Patents on the 9th September 1882.
The Honorable JOHN WILLIAM PLUNKETT of Dunstall Priory in the County of
Kent and of Park Square in the County of Middlesex "IMPROVEMENTS IN
APPARATUS FOR INDICATING AND RECORDING THE AMOUNT OF SALT IN THE WATER
OF STEAM BOILERS AND FOR INDICATING AND RECORDING THE DENSITY OF
SOLUTIONS BOILING UNDER PRESSURE FOR OTHER PURPOSES
"
My Invention has for its object to provide an instrument affording a ready
means of indicating and recording the amount of salt in the water of Marine
boilers and for indicating and recording the density of solutions boiling under
pressure for other purposes by the difference between the pressure and the
temperature of the water.
As is well known in the case of pure water a certain rise of temperature occurs
as the pressure increases but any undue increment of temperature disproportionate
to the pressure would indicate the amount of salt or other matter in solution.
According to my Invention I provide an instrument or apparatus connected
with or affixed to and in communication with the interior of the boiler or vessel
and subjected to the pressure and temperature therein in which instrument or
apparatus a pressure gauge and a pyrometer (or other temperature indicator which
will record accurately under pressure) are so combined in one instrument that their
Pies 21

page_text: differences of record will shew the amount of salt or other matter in solution.
The moving parts of the gauge and pyrometer will act upon discs or devices
which will by their conjoint movements give and record the indication necessary
to enable the amount of Salt or other matter in solution to be readily ascertained
in the manner hereinbefore mentioned. The apparatus may also if desired be
provided with an attachment or connection with the scum or brine cocks so as to
automatically open the same when necessary.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said John William Plunkett in the Great Seal Patent Office on the
9th March 1883.
The Honorable JOHN WILLIAM PLUNKETT of Dunstall Priory in the County of
Kent and of Park Square in the County of Middlesex
< IMPROVEMENTS IN
APPARATUS FOR INDICATING AND RECORDING THE AMOUNT OF SALT IN THE WATER
OF STEAM BOILERS AND FOR INDICATING AND RECORDING THE DENSITY OF
SOLUTIONS BOILING UNDER PRESSURE FOR OTHER PURPOSES
"
My said Invention has for its object to provide an instrument or apparatus
capable of affording a ready and efficient means of indicating and if necessary
recording the amount of salt in the water of marine boilers or for indicating and
recording the density of similar solutions boiling under pressure for other purposes
in a constant manner and without requiring manipulation or calculation The
principle on which the said instrument or apparatus is actuated or operated is by
virtue of the variations or differences between the pressure and the temperature of
such water or solutions-It is well known in the case of boiling pure water that
a certain or determinable rise of temperature occurs as the pressure definitely
increases from confined ebullition or other similar causes but any undue increment
or rise of temperature disproportionate to such pressure would indicate the amount
of saline or other foreign matter held in solution.
According to my said Invention I provide an instrument or apparatus connected
with or affixed to and in communication with the interior of the boiler or vessel
and subject to the pressures and temperatures existing and varying therein and in
which instrument or apparatus a pressure guage and a pyrometer of any known con-
venient form (or other temperature instruments which will accurately indicate and
record under pressure) are so combined in one instrument that their differences of
indication and record will shew the amount of salt or other matter held in solution.
The moving parts of the guage and pyrometer may act upon discs or devices
which will by their conjoint movements give and record the indications necessary
to enable the amount of salt or other matter held in solution to be readily ascer-
tained in the manner herein before mentioned The apparatus may also if desired

page_text: be provided with an attachment or connection with the scum or brine cocks so as
to automatically open the same when necessary or the said apparatus may be
arranged to give an audible alarm when any unsafe degree of saturation has been
reached.
From the accompanying diagram it will be readily understood how the com-
parative movements of a pressure guage and pyrometer needle may be so utilised
as to indicate and record their resultant differences as herein before mentioned so
as to present a constant simple and efficient salinometer or densimeter independent
of manipulation or calculation.
A represents the needle or pointer of any suitable pressure guage which constantly
indicates any variations of pressure by causing the said needle to advance or recede
along a conveniently graduated scale D drawn or formed to any desired units of
linear measurement so as to indicate the fractional and integral variations in pounds
pressure per square inch,
In combination with such ordinary pressure guage I may provide any suitable
known thermometer or pyrometer which will act under pressure and communicate
its movements resulting from variable temperatures to a shaft or spindle 6 carrying
a second index or pointer B and working through a tubular shaft a which carries
the pressure needle A before referred to the one needle being arranged to pass
beneath the other so as to allow each independent motion.
The pinions, racks, connections and gearing for transmitting the aforesaid
movements may be of any known kind as will be readily understood by those
fairly versed in the construction and operation of such instruments. The second
needle B which moves according to the fluctuations of the temperature of the fluid
within the boiler may also travel over a suitably corresponding graduated
temperature scale C to that of D (arranged according to tabulated comparative
relations well understood) so as to indicate a proportionate corresponding variation
of temperature It will be understood that in the case of pure water the variations
of pressure and temperature will correspond so that both the needles A and B will
be similarly simultaneously influenced and keep one beneath the other but imme-
diately the density of the boiling fluid under pressure increases the temperature
proportionately rises and thus causes the needle B to travel in advance of needle A
and so indicate such increase in density.
In order to conveniently indicate the degrees or limits of increasing density that
under any circumstances should be allowed I may provide a colored graduated
shield or fan E attached to the temperature needle B which under normal circum-
stances is hidden beneath a large white screen F carried by and moving with the
pressure needle A as represented at Y but which when the density of the water
increases moves out from underneath the latter as at Z thus exhibiting the degrees
or excess of such saline or other saturation or similar increase of density.
In practice it may be found convenient to so arrange the pyrometer that its
expanding or varying movement is not communicated to the temperature needle B
below or until 212 degrees Fahrenheit of heat has been attained within the boiler
so as to prevent the said needle continuing its retrograde movement after the
pressure needle A has returned to Zero
It will however be understood that mechanical detaching and driving or con-
trolling mechanism may be substituted for the arrangement above referred to
according to any well known manner.
Although I have described my Invention with reference to the accompanying
diagram I would have it understood that I do not limit myself to any precise
method of carrying it into effect as the details of the instrument or apparatus
may be considerably varied without departing from the essence of my said
Invention.
The essential features of my said Invention are the use of one instrument or
apparatus which indicates constantly in any usual manner the pressure and the
temperature to which a fluid in a boiler or similar receptacle is at any moment
subjected and by graduating the spaces representing respectively pounds of pressure

page_text: and degrees of temperature I cause these two indicators under normal circumstances
to move over such spaces at the same uniform rate as the pressure and temperature
may vary.
When however the fluid by evaporation or other similar causes contains an excess
of salts or matters in solution the density increases and the temperature indicator
will advance or move at a different or abnormal speed to the pressure indicator
which variation or divergence will constantly show mechanically measure and if
necessary record fluctuations of density within the boiler or receptacle.
It will further be easily understood that any variation of the movements of the
two. needles as aforesaid can be arranged to be permanently recorded as well as
only indicated for the time being Thus the second or temperature needle B could
be arranged to work a tell tale index or recording scale as represented at ƒ (pre-
ferably carried by the aforesaid needle screen F) forward to its maximum advance
but be incapable of returning the same so that at any time when the instrument is
inspected there may be a fixed record of the maximum density that has been attained
within the boiler or vessel.
Having now described and particularly ascertained the nature of my said
Invention and the manner in which the same is or may be used or carried into effect
I wish it to be understood that I am aware that it has heretofore been proposed to
ascertain the density of fluids by measuring its specific gravity or its boiling point
or both and therefore to these means in themselves I lay no claim but what I
consider to be novel and original and therefore claim as the Invention secured to
me by the herein before in part recited Letters Patent is.
An instrument or apparatus for indicating or indicating and recording the
density of liquids or solutions whilst boiling under pressure the said apparatus con-
sisting of means for indicating pressure and means for indicating temperature so
combined and in communication with the pressure and temperature in the boiler or
other vessel as by their conjoint action to give a constant indication or indication
and record of the density of the liquid in the said boiler or vessel substantially as
herein before described.
In witness whereof I the said John William Plunkett have to this my
Specification set my hand and seal this eighth day of March One thousand
eight hundred and eighty three.
JOHN. W. PLUNKETT. (L.S.)