A NEW OR INPROVED BOILER AND FURNACE COMBINED FOR HEATING AND CIRCULATING WATER OR OTHER LIQUIDS, RAISING STEAM, AND FOR OTHER SIMILAR PURPOSES
Year: 1875

page_text: LETTERS PATENT to James Keith, of Arbroath, in the County of
Forfar, North Britain, Gas and Water Engineer, for the Invention
of "A NEW OR INPROVED BOILER AND FURNACE COMBINED FOR HEATING AND
CIRCULATING WATER OR OTHER LIQUIDS, RAISING STEAM, AND FOR OTHER
SIMILAR PURPOSES."
Scaled the 20th June 1876, and dated the 27th December 1875.
PROVISIONAL SPECIFICATION left by the said James Keith at
the Office of the Commissioners of Patents, with his Petition, on
the 27th December 1875.
I, JAMES KEITH, of Arbroath, in the County of Forfar, North
Britain, Gas and Water Engineer, do hereby declare the nature of the
said Invention for “A New OR IMPROVED BOILER and Furnace COMBINED FOR
HEATING AND CIRCULATING WATER OR OTHER LIQUIDS, RAISING STEAM, AND FOR
OTHER SIMILAR PURPOSES," to be as follows:-
:-
This Invention relates more especially to the heating of greenhouses,
conservatories, and other buildings or structures by hot-water circulation,

page_text: through pipes, tanks, or other appliance, whereby the water is heated
much more rapidly and with much less fuel than by the boilers here-
toforc in use. The boiler is also applicable for heating water and other
liquids for domestic, sanitary, and commercial purposes.
The apparatus employed in carrying out this Invention consists of a
new or improved arrangement of boiler and inside heater, with down
centre flue, boiler casing, furnace and grate attachments, constructed
and connected as herein-after described, and which the Inventor pro-
poses to call "the rapid circulator and fuel economiser."
The boiler is of circular, oval, oblong, or square form, and circular
domed or flat on top, or with corrugated sides and top, with rounded or
square corners, and is constructed of either malleable or welded iron or
steel, cast iron, or any other metal capable of withstanding the heat.
The body and top of the boiler are composed of two shells, between
which the water circulates, and connected to the inside shell is a heater
or other shell having a flue or pipe carried down through its centre and
out at the side of the boiler, by which the flame and smoke pass directly
through the centre of the heater. The flames having to turn round and
down when at the top of the above fiue give an intense heating power,
and the draught is very strong and equal, being all drawn to the centre
of the heater before descending.
The above heater is properly connected to the inside shell or body of
the boiler both at its lowest and its upper part, thus causing a constant
and rapid circulation in the boiler itself whenever the least heat is
applied to it; all parts of the boiler expand, being surrounded or covered
with water. The heater has a flat or raised bottom, which is carried
down to within a short distance of top, and covers nearly the whole
surface of the fire, thus "frying" over the fire as it were, and allowing
the heat and flames to escape up between the outside edge of it and the
sides of the inside shell of the boiler, and after which passing up between
the said heater and the said inside shell on arriving at the top they turn
down through the centre of the heater again (as already described) and
pass through the side of the boiler, entering into the space between the
outside casing and the outside shell of the boiler, and after passing once,
twice, or more times round the outside and over the top of boiler they
enter into the funnel or chimney attached to the top plate of casing.
Suitable dampers and soot and cleaning doors are provided at proper
places in the funnel, boiler, and casing.

page_text: This new or improved boiler may also be used without the casing if
necessary, and have the funnel and Keith's patent gaswork damper
attached to the boiler on the side where the centre flue leads out, or the
boiler can be set and built in brickwork in an ordinary fashion.
The furnace is inside the boiler, the furnace door being in the side of
the boiler; the fire is therefore surrounded on all sides by a thin lining
of water constantly circulating. The boiler extends to within a few
inches of the furnace bar plate, and the space between the bottom
of the boiler and top of the bar plate is filled in with a thin lining of
fire-bricks moulded to suit to keep life in the fire when it is damped
down.
The whole apparatus stands on a metal frame provided with hinged
damping grate and ash pan and damper door arrangements complete.
No building work whatever is therefore required about the boiler, and
standing by itself it takes up very little room, and is very easily heated
up, having no surrounding brickwork to absorb the heat.
The flow or heat-circulating pipe or pipes are led from the very top of
the boiler, and the return or cold pipes from the lowest part, and are
connected to the boiler by suitable collars or sockets cast, welded, or
bolted on to the outside shell.
.
All the shells and heater can either be welded together in one picce,
or rivetted or bolted and jointed properly together, or otherwise con..
nected in separate parts.
When the boiler is used for steam raising purposes everything as
regards the bottom part of the boiler up to the top of the inside shell is
the same as already described, but the top part or steam portion is much
enlarged, and is constructed in every way the same as a large dome of
an ordinary steam boiler with man-hole, door, and other ordinary
appliances. The great advantages in the down centre flue for steam
raising purposes is that its being all under water no portion of the boiler
or flue is exposed to the fire or flames, but is surrounded or covered with
water, thus preventing burning and consequent danger, at the same time
giving intense circulating and heating power.
The said boiler, either for steam or hot water raising and circulating
purposes, owing to its peculiar construction has more direct and indirect
superficial heating surface than other boilers of the same size in use, while

page_text: its great heating powers, coupled with the minimum consumption of fuel,
renders it greatly superior to boilers at present in use for the purposes
specified. Instead of the central flue through the heater this fiue may
be dispensed with and a central heater hung down from the top or dome
of the boiler to give similar effects.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Keith in the Great Seal Patent Office on
the 27th June 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
KEITH, of Arbroath, in the County of Forfar, North Britain, Gas and
Water Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-seventh day of December, in
the year of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto me, the said James Keith, Her special
licence that I, the said James Keith, my executors, administrators,
and assigns, or such others as I, the said James Keith, 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
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 for "A NEW OR
IMPROVED BOILER AND FURNACE COMBINED FOR HEATING AND CIRCULATING WATER
OR OTHER LIQUIDS, RAISING STEAM, AND FOR OTHER SIMILAR PURPOSES," upon the
condition (amongst others) that I, the said James Keith, my executors
or administrators, by an instrument in writing under my, or their, or
one of 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 I, the said James Keith, do hereby declare
the nature of my said Invention, and in what manner the same is to

page_text: be performed, to be particularly described and ascertained in and by
the following statement in writing, reference being had to the accom-
panying Sheet of Drawings, and to the letters and numerals marked
thereon, that is to say:―
ว
My said Invention* relates more especially to the heating green-
houses, conservatories, and other buildings or structures by hot water
circulation through pipes, tanks, or other appliance, the water therefor
being heated in and circulated through my said new or improved boiler
much more rapidly and with much less fuel than by the boilers
heretofore in use. This boiler is also applicable for heating water and
other liquids for domestic, sanitary, and commercial purposes, and for
the raising of steam for motive power and other purposes.
The apparatus employed in carrying out this Invention consists of a
new or improved. construction or arrangement of boiler with inside
heater and down centre flue, boiler casing, furnace and grate attachments,
constructed and connected as herein-after described as a portable boiler,
and which I propose to call "the rapid circulator and fuel economiser."
And in order that the nature, novelty, and mode of performing my
said Invention may be properly understood, I will now proceed to
describe the several Figures on the Sheet of Drawings which I have
hercunto appended for the purpose of showing the best modes and
means I am at present aware of for putting the Invention into effect or
practice, the same reference letters and numerals indicating the same or
like parts in all the Figures where shown.
Figure 1 is a side elevation; and Figures 2 and 3 are a corresponding
vertical section, and a sectional plan respectively taken on the lines
11 and 2 - 2, each on the other of one modification of my said
new or improved boiler constructed in accordance with and illustrative
of my said Invention, while Figures 4, 5, and 6, are respectively a side
elevation, plan, and bottom view of the improved internal water heater
and circulator as removed from the flame, combustion, and heating
chamber above the grate and fire-box, and formed of cast iron, as well
as the outer shells of the boiler, but these as well as the former might
be constructed of malleable cast iron, cast or wrought steel, or of
malleable or welded iron or boiler plate, or of other metal capable of
withstanding the heat.

page_text: '
Referring to these Figures 1 to 3, the outer or main water containing
and heating shell 1 of the boiler proper is of a hollow, circular, or
annular shape, formed of inner and outer shells 2 and 3, jointed together
water-tight by flanges and screw bolts or pins at the bottom 4 where it
rests on, or is secured to the top of the shallow fire-box 5, both the
inner and outer shells 2 and 3 are closed in above by corresponding flat,
round, or domed tops 2', 31, leaving a nearly parallel close water space 1'
running into or connected with the side space 1, but the outer shell of
the boiler 1, 2, 3, might be of an oval, oblong, rectangular, or square
form, with a circular, domed, or flat top; and either made with plain
The
or corrugated sides and top, and with rounded or square corners.
outer case 3 has an inlet and return branch or faucet 6 formed at or
near the bottom, and a corresponding out flow branch 7, to which the
water circulating pipes not shown in the Drawing to be used for heating
purposes are jointed by spigot and faucet end pieces 61, 71, Figure 1,
or other equivalent in an ordinary manner; and the inner case 2 has
an open ended branch or spigot 21 jointed water-tight through a
faucet 3 in the centre of the top or dome 3' as a flue or fire-box
cleaning door covered in by a lid 21, all so that the water enters and
returns at the branch 6, circulating up through the close wall chamber
or body of the boiler 1, 1', out through the branch 7.
A new or improved internal water heater and circulator A of the
form and construction shown in Figures 4, 5, and 6 (or other equivalent
shaped close shell) having a flue or pipe A' carried down through its
centre to near the bottom, and out at the side by the flue B through the
shell 1, 2, 3, of the boiler, so that the flame and hot gases pass up from
the fire through the narrow or annular space a¹ between this box or
heater A, A, and the inner shell 2 directly down through the centre A'
of the licater A, and out through the flue B. The flames and hot gases
when at the top of the heating chamber a¹ having thus to turn down
through the flue A' in the centre of the water heater A give an intense
heating power and great heating surface, and a strong and uniform or
steady draught by being all drawn to the centre of the heater A. This
heater A, A, is preferably formed with a vertical duct A at one side
directly connected with the segmental close water chamber within it,
which is properly connected or jointed water-tight by one or more
branches A" at the lower end to the inside case 2 of the boiler, and by
one or more spigot branches A at top to a faucet in the crown or

page_text: dome 2¹of this case, all which produces a rapid and constant flow of
hot water through the heating box A, A', and its branches A", A", and
insures or causes a great and constant circulation of hot water through
the whole boiler and its branches 6 and 7 when the smallest heat or firo
is applied within the fire-box a as indicated by the darts in the water
spaces in Figure 2, the construction of the boiler as described; the
heating surface being surrounded or covered with water allows all the
parts to expand equally, and thus maintains tightness at the joints.
4
The heater A, A', has a flat bottom, as seen in Figure 6, with radial
heating surface ribs A³, which are carried up the sides to within a short
distance of the top, thus spreading over nearly the whole fire, and filling
the greater part of the heating chamber above it, and allowing the heat
and flames to pass up between its outside ribbed edge or side and tho
inner heating surface of the inside shell 2, and on reaching the top they
turn down the central flue A¹ of the heater again (as already described)
passing out through the side 1, 2, 3, into and round the lower outside
heating flue or space 10 between the outside shell 3 and outside case 11
of an outer heat flue or chamber formed near the top of the boiler, and
then up through the division 12 into and round a second or upper flue
13 above the former out into the chimney or flue 14 leading thereto, all
as indicated by the red arrows in Figures 2 and 3. These upper flues
are enclosed within the case 11, shown as formed with square sides or
plates covered in below and above at 15 and 16 with vertical corner
plates 17, fitted with flue and soot cleaning doors 18 opposite each flue,
all as shown particularly in Figures 1 and 3, and although only two
flues 10 and 13 are here shown it is to be understood that there might
be three or more, so that the heated gases may pass off by these two,
three, or more times, according to the height of the boiler, and a
swivelling or drawing damper 19 may be formed at the neck or flue
leading to the chimney 14.
This new or improved boiler may also be used without the flue case 11:
if desired, and have the funnel 14 and "Keith's patent gas-work
damper" attached to the boiler on the side where the centre flue B
leads out, or the boiler can be set and built in brickwork in any ordinary
manner.

page_text: water space 1 below this surrounding the fire on all sides, admitting of
a constant circulation of the water from this lowest part of the boiler.
The lower or furnace part 5 of the fire-box a, on which the boiler rests,
containing the burning fuel, is a few inches in depth, and lined with
fire-brick 5¹ moulded to suit, which would keep life in the fire when it i
was damped down.
The whole boiler and apparatus so far described stands or rests on a
circular hollow metal frame 20, forming the ash-pit, and fitted with
cleaning-out doors 21 and valve 21', for regulating the admission of the
air thereto to support combustion, as shown particularly in Figure 1.
This frame 20 carries at its upper edge immediately below the fire-box 5
a dumping fire-grate 22 swivelling in bushes 22, secured at the front
and back, and by which the fire can be emptied into the ash-pan 20¹
beneath in a few seconds by simply turning the handle 23 shown
particularly in Figure 1. The whole furnace and boiler are therefore 1
portable and self-contained, requiring no building work whatever, and
thus standing by itself takes up very little room, and is very easily
heated up, having no surrounding brickwork to absorb the heat.
The outflowing heat circulating pipes not shown in the Drawings are
led from the very top of the boiler, and the return or cold pipes from a
the lowest part are connected to the boiler, as herein-before described,
by suitable collars or sockets cast, welded, or bolted on to the outside
shell at 7 and 6 respectively, Figures 1 and 2.
All the shells and heater can either be welded together in one piece or
rivetted or bolted and joined properly together, or otherwise connected
in separate parts, according to the nature of the material of which they
are formed.
"
When the boiler is used for steam raising purposes everything as
regards the lower part of the boiler and furnace up to the top of the
inside shell 2 is the same as already described, but the top part or steam
portion 1', 3', of the outer shell 3 is made larger and higher, and is
constructed in every way the same as the large dome of an ordinary
steam boiler, with man-hole door and other ordinary appliances. The
great advantages in this down centre fluc A' for steam raising purposes
are that its being all under water, no portion of the boiler or flue a
is exposed to the fire or flames, but is surrounded or covered with water,

page_text: thus preventing burning and consequent danger, at the same time giving
intense heating and great circulating power.
The said boiler, whether for generating steam or for water heating
and circulating purposes, owing to its peculiar construction, has more
direct and indirect superficial heating surface than other boilers of the
same size in use, while its great heating powers, coupled with the
minimum consumpt of fuel required by it, renders it greatly superior to
boilers at present in use for the purposes specified. Instead of the
central flue A' through the heater this flue may be dispensed with and a
central heater hung down from the top or dome of the boiler and
connected to its side to give similar effects.
In the Drawing shown the boilers are made of cast iron in three
separate pieces, namely, the circulating inside heater A, the inside shell
2, and outside shell 3. These three pieces are all fitted together.
(enclosing the water space or case 1 of the boiler, as described) and
secured and jointed in a new or improved manner by being bored and
scrow pinned at once and then carefully rusted with very fine flour iron
rust without salamoniac. This form of joint being relieved from all
strain is equal to the solid iron itself; also, by making the boilers for
hot water of cast iron, as shown and described, enables all the parts of
the Invention to be fully and minutely carried out, besides, as is well
known, cast iron, when properly used, stands the action of the fire and
water much better than malleable iron. The sides and bottom of the
heater A, A', are corrugated, and are preferably protected and strength-
ened by flat thin ribs or bars A' cast on same, as shown; these serve to
give strength and sharper acting heating surface than if plain, and at
the same time they disperse the flames in a proper manner within the
heat chamber a or adjacent parts, and the inner shell 2 of the heat
chamber might in some cases be similarly formed with ribs, preferably
opposite the hollows in the heater, to further assist the radiating action
and dispersion of the heat, as shown in Figure 3, and a blow-off tap 1"
or other equivalent is fitted at the lowest part of the water space 1 to
draw off any sediment that may deposit there.
.
Having now described the nature of my said Invention, and the
manner in which the same is or may be performed, I have to state that
I do not restrict myself to the precise details herein described or
delineated, but what I believe to be novel and original, and therefore

page_text: claim as the Invention secured to me by the herein-before in part
recited Letters Patent is,-
First. The general construction or arrangement and combination of
the parts of a portable and self-contained water heating and circulating
or steam generating boiler, furnace, and heating flues, and mode of 5
jointing and putting the parts together, all substantially as herein-before
described in reference to and shown in the accompanying Drawings or
any more modification thereof.
Second. The construction and use of an internal water heating and
circulating vessel with internal flue A, A', and mode of connecting the 1
same to the boiler 1, 2, 3, to insure circulation, all substantially in the
new or improved manner herein described in reference to and shown in
the accompanying Drawings or any mere modification thereof.
In witness whereof, I, the said James Keith, have hereunto set
my hand and scal, this Twenty-fourth day of June, in the
year of our Lord One thousand eight hundred and seventy-
six.
Witness,
JOHN BROWN,
Patent Office,
96, Buchanan Street,
Glasgow.
JAMES KEITH. (L.S.)