IMPROVEMENTS IN APPARATUS, OR AN IMPROVED APPARATUS FOR HEATING WATER FOR THE SUPPLY OF STEAM BOILERS, WHICH IMPROVE- MENTS OR APPARATUS ARE ALSO APPLICABLE IN SOME CASES FOR THE PREVENTION OF INCRUSTATION IN STEAM BOILERS
Year: 1859

page_text: LETTERS PATEN to Thomas Holt, of Lower Place, in the
or
Rochdale, and County of Lancaster, Engineer, and John Brown, of
Oxford Street, Well Field, in the same Parish and County, Agent, for the
Invention of "IMPROVEMENTS IN APPARATUS, OR AN IMPROVED APPARATUS
FOR HEATING WATER FOR THE SUPPLY OF STEAM BOILERS, WHICH IMPROVE-
MENTS OR APPARATUS ARE ALSO APPLICABLE IN SOME CASES FOR THE
PREVENTION OF INCRUSTATION IN STEAM BOILERS."
°
Sealed the 8th September 1859, and dated the 26th April 1859.
PROVISIONAL SPECIFICATION left by the said Thomas Holt and John
Brown at the Office of the Commissioners of Patents, with their
Petition, on the 26th April 1859.
We, THOMAS HOLT, of Lower Place, in the Parish of Rochdale, and County
of Lancaster, Engineer, and JOHN BROWN, of Oxford Street, Well Field, in the
same Parish and County, Agent, do hereby declare the nature of the said
Invention of "IMPROVEMENTS IN APPARATUS, OR AN IMPROVED APPARATUS FOR
HEATING WATER FOR THE SUPPLY OF STEAM BOILERS, WHICH IMPROVEMENTS OR
APPARATUS ARE ALSO APPLICABLE IN SOME CASES FOR THE PREVENTION OF INCRUS-
TATION IN STEAM BOILERS," to be as follows:-
Our Invention consists in the use of a vessel or cistern placed in juxta-
position with that end of the boiler which is remote from the furnace, so as to
be impinged upon by the flame and heated products. of combustion issuing.
from the furnace through the flue or flues. This cistern serves as a reservoir,

page_text: through which the feed water before entering the boiler is made to pass and
to have its temperature raised by heat derived from the vapor or flame inter
cepted by the cistern.
It consists further in adapting and using the cistern or vessel before
mentioned for a receptacle of spent tanners' bark, bark knots, or other similar
matters commonly applied to prevent incrustation and scale in boilers, supplied
with water charged with earthy or saline matters, against the detrimental
properties of which the substances named are known to act as antidotes.
The spent bark being deposited from time to time in the cistern in adequate
quantities, yields up to the feed water the beneficial extractive matter. The
cistern may have an extra opening and lid to admit the bark, and may be
furnished with an inner vessel with perforated sides to contain it, but this is
not essential.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Holt and John Brown in the Great Seal Patent
Office on the 17th October 1859.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, THOMAS
HOLT, of Lower Place, in the Parish of Rochdale, and County of Lancaster,
Engineer, and JOHN BROWN, of Oxford Street, Well Field, in the same Parish
and County, Agent, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-sixth day of April, in the year of our Lord
One thousand eight hundred and fifty-nine, in the twenty-second year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us, the
said Thomas Holt and John Brown, Her special license that we, the said
Thomas Holt and John Brown, our executors, administrators, and assigns, or
such others as we, the said Thomas Holt and John Brown, our executors,
administrators, or assigns, should at any time agree with, and no others, from
time to time and at all times thereafter during the term of years 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 of "IMPROVEMENTS IN APPARATUS, OR AN
IMPROVED APPARATUS FOR HEATING WATER FOR THE SUPPLY OF STEAM BOILERS,
WHICH IMPROVEMENTS OR APPARATUS ARE ALSO APPLICABLE IN SOME CASES FOR THE
PREVENTION OF INCRUSTATION IN STEAM BOILERS," upon the condition (amongst
others) that we, the said Thomas Holt and John Brown, our executors or

page_text: administrators, by an instrument in writing under our, or their, or one of
our or 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 we, the said Thomas Holt and John Brown, do
hereby declare the nature of our said Invention, and the manner in which
the same is to be performed, are particularly described and ascertained in
and by this present instrument in writing, with the aid of the annexed
Drawing, to which reference is made by means of alphabetical and numerical
characters marked thereon, similar parts or things being marked and referred
to by similar characters (that is to say):-
The said Invention applies to boilers in which steam is generated for the
supply of stationary land engines, and has for its objects, firstly, the saving of
fuel in the process of evaporation by raising the temperature of the feed water
before the same passes into the boiler by means of heat, which under ordinary
arrangements is lost or wasted; and, secondly, the prevention of scale or
incrustation on the internal surface of the boiler, by the purification of the
feed water before the injection of the same into the boiler, from certain saline
or earthy impurities, by the deposition of which within the boiler scale would
be formed.
According to the arrangements of furnaces and flues most generally adopted
in heating steam boilers, the vapors and products of combustion issuing from
the furnace are first made to traverse a flue or flues leading through or under
the boiler to the damper end thereof, or that remote from the furnace; on
reaching which the current of vapor has its direction reversed, and is made to
return along a second flue in contact with some part of the heating surface of
the boiler to the furnace or firing end, from which it is again made to resume
its original direction through a third flue, in contact with fresh heating
surface; and after traversing the length of the boiler a third time, is ultimately
allowed to pass through the damper to its final outlet by the chimney. There
is also a form of boiler well known as the tubular or multitubular, in which
the smoke or vapor, divided or distributed through a number of small tubes,
makes only one passage or traverse along the boiler's length internally, and.
then passes through the damper without any reverberation of its current or
renewal of contact with the boiler.
All the varieties of arrangement have, however, one feature in commen,
namely, that the stream of vapor from the furnace, after traversing the first

page_text: flue or flues or tubes, as the case may be, is on reaching the damper end of
the boiler impelled forcibly against the masonry of the containing wall of a
cross or transverse flue adjacent to the end of the boiler, or in multitubular
boilers against the external side or end of the smoke box. In either case the
necessary consequence is the dissipation of a portion of the heat of the
gaseous current and its diffusion through the obstructing body thus encountered,
which heat is thus not only lost or wasted, but operates with absolute detriment
by burning away the material of the flue wall or the plates of which the
smoke box is composed.
Our Invention aims at the conversion of this heat, so injuriously lost and
wasted, to the useful purpose of heating the feed water, thereby saving the
cxpenditure of so much fuel as would be required to raise the whole of the
water evaporated from its ordinary temperature to the same degree of heat as
the feed water thus treated attains before entering the boiler. And the said
Invention consists in the mode of availing ourselves, for the purpose specified,
of this heretofore injuriously wasted heat, that is to say, in the use, adaptation,
and application of a vessel, tank, or cistern placed in juxtaposition with that
end of the boiler which is remote from the furnace, in such a position as to be
impinged upon by the flame, vapor, and heated products of combustion pro-
ceeding from the furnace, and issuing from the said end of the boiler through
the mouth or opening of the first flue (or flues), the said tank serving as a
reservoir, through which the feed water before entering the boiler is made to
pass, and to have its temperature raised by the heat derived from the vapor or
flame intercepted by the said tank, or passing in contact therewith. The
capacity of the said tank should be somewhat more than is sufficient to contain
such a quantity of water as will supply the demands of the boiler for a length
of time equal to that required to raise the feed water in the tank to the
temperature at which it is proposed to allow it to enter the boiler, which we
may suppose to be from 200° to 230° Fahrenheit. The tank is to be con-
structed of rivetted boiler plate, and both as respects form and construction, as
well as material, must be made strong enough to withstand the same pressure
as the boiler. In shape it should be adapted to occupy its destined position at
the end of the boiler, and at the same time to present the largest practicable
extent of heating surface to the currents of vapor to which it is exposed.
That the Invention, and also the construction and application of the apparatus
for carrying the same into effect, may be more certainly understood, we shall
further elucidate and exemplify them by a description and explanation of an
apparatus represented in Figures 1, 2, 3, and 4 of the accompanying Drawing
as applied to a boiler of an ordinary construction.

page_text: Figure 1 is a vertical and longitudinal section of part of a boiler with the
apparatus; Figure 2 is a plan view; Figure 3 is a transverse vertical section
on an intersecting plane at the dotted lines 1, 2, (Figures 1 and 2); and
Figure 4 is a like section at the dotted lines 3, 4. A is the boiler; B is one of
two flues traversing the interior of the same lengthwise; C is the transverse flue
at the end of the boiler, into which the flues B previously mentioned issue, and
through which the smoke which they convey finds a passage into the external
side flues D, D. The latter return to the furnace end of the boiler, where
they converge and unite in a third external flue E, which passes under the
middle of the boiler, and thence away to the chimney. F is the damper;
G, G, is the boiler seating, forming also the separation between the side flues
and the middle flue; a is the tank or reservoir for containing the feed water
to be heated. It is a narrow oblong vessel composed of boiler plates rivetted
together in the usual manner, and it is curved at its summit towards the end
of the boiler against which its overhanging extremity rests, so as to cover in
the transverse flue C. The details of its configuration will be easily gathered
from the Drawing. b is the pipe through which the cold feed water is injected'
by the force pump, or in the case of a low-pressure boiler, it may be supposed
to represent the stand pipe. It is provided with a stop-cock 6, by which the
supply from the pump may be suspended or regulated. c is a pipe through
which the heated feed water passes from the tank into the boiler under the
pressure exerted by the force pump or by the column of water in the stand
pipe; d is a pipe furnished with a stop-cock d¹, and forming a communication
between the interior of the boiler and the feed pump when the stop-cocks b¹, d¹,
are both open, and between the boiler and the tank when the cock b¹ is closed
and the cock d opened; e is a man-hole, affording access to the interior of
the tank; f is a safety valve; g is a mud pipe for clearing the tank of
sediment. It has its outlet in an adjacent sewer or other convenient place;
its valve g' is opened or closed by means of a vertical rod passing through a
stuffing box on the roof of the tank, and caused to ascend or descend upon its
handle being turned by a screwed bush in which it works with a corresponding
screw at g. It will be seen that the inner vertical side of the tank a occupies
nearly the same position as the inner face of an ordinary flue wall, and is
presented towards the mouths of the internal flues of the boiler so as to
intercept the stream of flame and vapor emanating from the furnaces. A-
portion of the bottom of the tank is also exposed to the flue E, which passes
under it. Heat will, therefore, necessarily be imparted to the contained water,
and the cold water entering by the pipe 6 having to traverse the whole breadth

page_text: of the tank to reach the feed pipe c, no portion of it can pass without receiving
its due proportion of such heat.
The foregoing description will suffice to make our Invention and the method
of applying and carrying the same into effect intelligible to any person
reasonably conversant with the subject to which it relates. It must, however,
be understood that although we have here described and delineated a particular
arrangement as being to the best of our knowledge the most eligible, in the
case supposed, we have done so by way of example merely, and that we do not
restrict ourselves as to the form and dimensions, nor as to the exact position
of the tank or reservoir, nor to the special arrangements for connecting the
same with the supply pipe on the one hand, or with the boiler on the other;
all which must necessarily be in a great measure arbitrary, and from their very
nature subject to modification and variation according to the requirements of
each individual case, and controlled by the skill and judgment of the engineer
or workman under whose direction the apparatus is constructed. It is obvious
that the tank might be attached to and formed as a continuation or as a
compartment of the boiler itself, especially in the case of a multitubular
boiler, to which it might be applied in the form of a circular chest imme-
diately behind the smoke box, and also that one tank of sufficient length
might be made to serve two or more boilers arranged side by side.
In the Diagrams, Figures 5 and 6, we have suggested two variations of the
form of the tank, such as appear to us judicious in the supposed cases of
boilers set in the manner there represented. Figure 5 shews a boiler set with
what is termed a circulating draught, that is, one in which the smoke is first
conducted in the direction indicated by the arrow 5, returning as shewn by the
arrow 6, thence in the direction 7, then under the boiler at the furnace end
as at 8, and finally along the direction 9, 10, 10, 11, to the chimney. The
tank is shewn at a of a somewhat modified horizontal configuration, sufficiently
explained by the Drawing, and which will be at once seen to be adapted to
the arrangement of the boiler flues. Again, in Figure 6, we have sketched a
boiler set with what is called a split draught, dividing at the front, in which
the course of the smoke is as indicated by the arrow 12 taken downwards at
the end, as shewn by the twisted arrow 13, returning under the boiler in the
line of the dotted arrows 14, 14, dividing at the front, as shewn at 15, 15, and
then reaching the chimney by separate flues, as at 16, 16, 17, 17, which
ultimately converge at 18, 18. The horizontal configuration which we prefer
for the tank in this case is shewn at y.
We have stated the second object of our Invention to be the prevention of

page_text: scale or incrustation in steam boilers by the previous purification of the feed
water. It is well known that some of the salts of lime and magnesia remain
in solution and suspended in water at low temperatures, but are precipitated in
a solid form upon the water acquiring a temperature more nearly approaching
the boiling point. It is this peculiar property of the substances mentioned
which causes them after entering the boiler in solution to be deposited therein,
and to adhere to the internal surface in the form of that scale or incrustation,
which intervening between the metal and the water, impedes the due trans-
mission of heat, thereby occasioning a greatly increased consumption of fuel,
and at the same time rapidly wearing out the boiler by allowing the plates to
be burnt. Now, it is obvious that the use of our apparatus is simply, and of
itself to a great extent, a preventive of this evil by causing the impurities of
the feed water to be separated and deposited in the tank before the water
passes into the boiler. But besides the agency of heat, there are certain
known substances which experience has shewn to be efficacious aids against
this mischief by causing the deposit of saline or earthy matter to take place in
the shape of a powder which does not adhere to the surface of the boiler, and
is consequently easily removable by blowing off. Tanners' bark and spent
bark or bark knots have this property in an eminent degree when brought into
contact with some of the contaminating matters most frequently present in
water. That further part of our Invention, therefore, which has reference to
this object consists in using the tank or heating vessel herein-before described
as a receptacle for tanners' bark, spent bark, bark knots, or other similar
matters applicable to prevent incrustation and scale in boilers supplied with
water charged with earthy or saline matters against the detrimental properties
of which the substances named have been found to be antidotes.
or bark knots may be thrown into the tank either loose or in a bag, and
renewed from time to time as their beneficial extractive matter becomes
exhausted; but the most convenient mode is to suspend them within the tank
in a receptacle of netted wire or in a sheet iron vessel closely perforated with
moderately large holes. The quantity of bark requisite will of course be
variable according to its own quality, and according to, the state of the water
used, so that no rule can be laid down on that head.
The bark
Having now set forth the nature of our Invention and explained the
manner of carrying the same into effect, we finally declare and desire it to be
understood that we do not claim as of our Invention the use of bark knots or
of any other substance as a preventive of incrustation in steam boilers, but
only the manner of using and applying the same to purify the water before it
enters the boiler by means of the apparatus herein-before described; and that

page_text: what we do claim as new and of our Invention, and the subject of the Letters
Patent herein-before mentioned, is,
Firstly, the use of a tank, vessel, or cistern, in juxtaposition with the
boiler at the end thereof remote from the furnace, for the purpose of receiving
and beating the feed water in its passage to the boiler in manner herein-before
described, however the construction, form, or position of the said vessel or tank
may be modified or varied, so long as the essential character of the apparatus
is retained.
And, secondly, the use and application of the said heating tank as a 'receptacle
for tanners' bark, spent bark, bark knots, or other similar matters applicable
for the prevention of scale or incrustation left or deposited by feed water
charged with any earthy or saline matters against the mischievous effects of
which the substances named operate as antidotes or preventives.
In witness whereof, we, the said Thomas Holt and John Brown, have
hereunto set our hands and seals, this Fifteenth day of October, in
the year of our Lord One thousand eight hundred and fifty-nine.
L.S.)
Signed and sealed by the said Thomas
Holt and John Brown, in the pre-
sence of
JNO. TAYLER, Patent Agent,
Manchester.
JOHN BROWN. (L.S.)