IMPROVEMENTS IN STEAM BOILERS
Year: 1858

page_text: PROVISIONAL SPECIFICATION left by the said Thomas Ivory, at the
Office of the Commissioners of Patents, with his Petition, on the 21st
January 1858.
I, THOMAS IVORY, of Edinburgh, Advocate, do hereby declare the nature of
the said Invention for "IMPROVEMENTS IN STEAM BOILERS," to be as follows:--
The usual mode of generating steam for working engines, is by employing
the steam directly generated from water in contact with a metallic or other
heating surface to raise or sustain the temperature of a much larger body of
water than is necessary to supply the quantity and pressure of steam required
by an engine.
Now the principle or nature of my Invention is to heat no more water at a
time than is necessary for generating the quantity and pressure of, steam
required by the engine, and to convey as it is generated, all the steam produced
by that body of water immediately into the engine to act; as a moving power,
means being adapted to keep up a continuous supply of fresh water to replace
what is converted into steam, so that the steam-generating body of water shall
preserve always, as nearly as possible, the same level. For this purpose..

page_text: make a separation between the body or quantity of water necessary for
generating the required quantity and pressure of steam, and the other or feed
water, the steam-generating body of water being contained in one vessel or set
of vessels or tubes, and the feed water being contained in a separate vessel
situate above the level of the steam-generating vessel, but having a communi-
cation with it through which the water in the feed vessel may flow, or be
caused to flow to the extent required for supplying the quantity of water
evaporated in the steam-generating vessel.
In order to secure a continuous flow of water from the feed into the steam-
generating vessel, the steam generated is caused to communicate its pressure to
the water in the feed vessel, so as to maintain, as nearly as possible, the same
pressure in both vessels or sets of vessels.
For this purpose, the steam is either admitted directly to the upper surface
of the feed water or is caused to communicate its pressure through a piston.
I do not, however, confine myself to this mode of maintaining an uniform
pressure throughout the water.
In order to regulate the supply of the feed water, an arrangement of slide
or other valves is provided, either self-acting or otherwise, so as to close either
wholly or partially the communication between the feed and the steam-
generating vessels, or the communication between the steam generated and the
upper portion of the feed water or the piston before mentioned.
The fire or other heat-producing agent, is as far as possible made to act only
upon the water contained in the steam-generating vessel, and the whole of
that water is brought as nearly as possible into direct contact with the heating
surface.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
+
by the said Thomas Ivory in the Great Seal Patent Office on the 21st
July 1858.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
IVORY, of Edinburgh, Advocate, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of January, in the year of our Lord
One thousand eight hundred and fifty-eight, in the twenty-first year of Her
reign,did, for Herself, Her heirs and successors, give and grant unto me,
the said Thomas Ivory, Her special license, that I, the said Thomas Ivory,
my executors, administrators, and assigns, or such others as I, the said

page_text: Thomas Ivory, 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 thercin 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 "IMPROVEMENTS IN
STEAM BOILERS;" upon the condition (amongst others) that I, the sail Thomas
Ivory, by an instrument in writing, under my hand and seal, 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 Thomas Ivory, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement (that is to say):-
My Invention of "Improvements in Steam Boilers," consists in constructing
them so as to admit of generating steam therein in the manner herein-after
described. The usual mode of generating steam for working engines is by em-
ploying the steam directly generated from water in contact with a metallic or
other heating surface to raise or sustain the temperature of a much larger
body of water than is necessary to supply the quantity and pressure of steam
required. by an engine. Now the principle or nature of my Invention is to
heat no more water at a time than is necessary for generating the quantity and
pressure of steam required by the engine, and to convey as it is generated all
the steam produced by that body of water immediately into the engine to act
as a moving power, means being adopted to keep up a continuous supply of
fresh water to replace what is converted into steam, so that the steam-gene-
rating body of water shall preserve always, as nearly as possible, the same level.
For this purpose, I make a separation between the body or quantity of
water necessary for generating the required quantity and pressure of steam,
and the other or feed water, the steam-generating body of water being contained
in one vessel or set of vessels or tubes, and the feed water being contained in
a separate vessel, which may be situated above the level of the steam-generating
vessel, but having. a. communication with it through which the water in the
feed vessel may, flow, or be caused to flow, to the extent required for supplying
the quantity of water evaporated in the steam-generating vessel.
In order to secure a continuous flow of water from the feed into, the steam-
generating vessel, the steam generated is caused to communicate its pressure
to the water in the feed vessel, so as to maintain, as nearly as possible, the

page_text: same pressure in both vessels or sets of vessels. For this purpose, the steam
is either admitted to the upper surface of the feed water, or is caused to com.
municate its pressure through a piston, which it is preferred should rest on the
upper surface of the feed. water. I do not, however, confine myself to this
mode of maintaining an uniform pressure throughout the water.
In order to regulate the supply of the feed water, an arrangement of slide
or other valves is provided either self-acting or otherwise, so as to close either
wholly or partially, the communication between the feed and the steam
generating vessels or the communication between the steam generated and the
upper portion of the feed water or the piston before-mentioned.
The fire or other heat-producing agent is as far as possible made to act only.
upon the water contained in the steam-generating vessel, and the whole of that
water is brought as nearly as possible into direct contact with the heating:
surface.
Having thus stated the nature of my Invention, I will proceed to describe.
more particularly the manner of applying it to boilers. Taking the case of a
single flue boiler it is divided longitudinally by means of a vertical partition.
into two compartments, one of which is intended to contain the feed water or
the body of water to be supplied as required to be evaporated; and the other
compartiment is intended to receive a continuous supply of a portion of such
feed water in order that it may be rapidly converted into steam, and passed
from this compartment to the engine. This steam-generating compartment is
placed over the fire-place, and a portion of the flue at the back of the same, so
that the greatest part of the heat from the fire may be applied directly to it
beneath the comparatively thin stratum of water contained in it, the upper part.
of this compartment forming a steam chest, from which the steam is taken in
the usual manner by the ordinary steam pipe leading to the engine. At the
lower part of the feed water compartment there is a channel of communication:
between the two compartments, the feed water being admitted thereinto at the
end farthest from the steam-generating compartment, and allowed to pass
therefrom at the end nearest to the same in regulated quantities through an
opening or passage governed by a valve or cock. This communication is kept
full of water, and is made to surround the flue. It is preferred that the water
above the flue in this communication should not exceed an inch in depth, but
this is not essential, and it is preferred that the opening for the entrance of the
feed water from the main body of water into the communicating passage.
should be underneath the flue, and that the opening for the entrance of the
feed water from the communicating passage into the steam-generating com-
partment should be above the flue. At the upper part of the feed water

page_text: compartment there. is a communication with the steam-generating compart- -
ment; an opening or passage governed by a valve or cock being placed
between them so as to allow the steam from the latter to enter the former, and
press upon the surface of water or of a piston or float, in order to keep up the
supply of the feed water to the steam-generating compartment as required.
The communication may be either wholly or partially closed by means of the
valve or cock.
The opening or passage (governed by the valve or.cock) for admitting the
feed water into the steam-generating compartment is placed at such a distance"
from the fire box or furnace, or if gas be used from the gas burning box or
furnace, as may be suitable to contract the limits of the steam-generating
compartment, and to keep its surface exposed to the action of the heat within
the required proximity to the fire or other heating agent.
The mode of generating steam in boilers constructed as above described is:
as follows: Water is to be admitted into the steam-generating compartment"
up to the required level, and both the feed water compartment and the
channel of communication for supplying the feed water to the steam-generating
compartment are to be quite filled with water. The opening or passage of
communication between the two compartments at the lower part (that is the.
feed water supply opening or passage) is to be quite closed by its valve or
cock, and the opening or passage at the upper part (that is the communication
between the steam-generating compartment and the upper part of the feed:
water) is to be made quite open by means of its valve or cock. As soon as
the heat from the fire directly applied to the comparatively thin stratum of
water in the steam-generating compartment situated over it has generated the
required pressure of steam therein, the communication between the lower parts
of the two compartments is to be opened to the extent necessary to let in a :
fresh supply of the feed water to compensate for the quantity evaporated, and :
the steam is passed to the engine in the usual manner. When the feed water.
compartment requires to be refilled, the communication between the two
compartments, both at the lower and at the upper part is closed; an opening is
made by means of a cock or valve in the upper part of the feed water com-
partment, so as to allow the steam to escape into the air, and water may be
supplied to the said compartment through another opening at the top of the
same, with a valve or cock inserted in it, such water entering the compart-
ment at simple atmospheric pressure; or both the communications at top and
bottom may be closed without an opening for escape of the steam.into the :
atmosphere and fresh water supplied to the said compartment through a
communication near the top of the same, the effect of which will be, that the

page_text: vapour in the upper part of the compartment will become condensed, a partial
vacuum will be produced, and the water forced in by atmospheric pressure
until the compartment is again filled.
The boiler may also be constructed similar to that above described, only
without a large feed-water compartment or reservoir forming part of the
boiler, and having its upper surface in direct communication with the steam-
generating compartment, so as to be acted upon as required by the steam, in
order to cause the necessary supply of the feed water; the requisite supply of
water in this case being effected by means of a force pump. In this case, the
only part of the boiler which may be said to act as a feed water compartment,
is that which, in the instance above described, formed the channel of com-
munication between the two compartments. This communication, which may
be called the feed water compartment, is to be kept constantly full of water,
and to surround the flue, and it is to be fed with the requisite amount of water
to compensate for the quantity evaporated, by means of a force pump, so
arranged as to be capable of forcing in the amount of water necessary to
maintain the required level of water in the steam-generating compartment.
The water may be thus forced in at a part of the compartment underneath the
flue, at the chimney end of the boiler, and the supply may be regulated either
by hand or by self-acting means; as for instance, by a pyrometer acting on a
lever in such a manner as to enlarge the orifice of supply when the heat is so
great as to produce a rapid evaporation, and contract the same so as to
diminish the supply when the heat only produces a slow evaporation.
The above description refers to boilers with single fire-places and flues, but
my Invention may also be adapted to boilers in which there are more than one
fire-place, and a corresponding number of flues; also, to multitubular boilers,
the chief necessary arrangement in all cases being, that the main body of water
shall be separated from that limited portion which is, for the time being, to be
converted into steam within such distance from the fire box or furnace as may
be found necessary to insure the direct application of the greatest amount of
heat, and that the supply of fresh water to compensate for that which is
evaporated shall be kept up.
Having thus described the nature of my Invention, and in what manner the
same is to be performed, I would have it understood that what I claim as of
my Invention is the construction of steam boilers in which there is a
separation between the main body of water, (to the whole of which heat is
usually applied in order to convert it into steam, but) which I only employ as
feed water, and the limited portion of such water (necessary for generating the
required quantity and pressure of steam) to which the heat of the fire or other

page_text: eat-producing agent is more directly applied, so as to convert it into steam,
as combined with the means of supplying the required amount of feed water
to the steam-generating compartment, as described.
In witness whereof, I, the said Thomas Ivory, have hereunto set my
hand and seal, the Nineteenth day of July, in the year of our Lord
One thousand eight hundred and fifty-eight.
T. IVORY. (L.S.)
Witness,
JOHN C. CHRISTIE, Witness,
No. 4, Duncan Street, Newington, Edinburgh,
Writer to the Signet.