IMPROVEMENTS IN TURNACES FOR THE CONSUMING OF THEIR SMOKE
Year: 1872

page_text: LETTERS PATENT to Duncan M°Coll, Bricklayer and Furnace Builder,
and James Gillespie, Master Slater, both of Paisley, in the County
of Renfrew, North Britain, for the Invention of "IMPROVEMENTS IN
TURNACES FOR THE CONSUMING OF THEIR SMOKE.”
Sealed the 27th December 1872, and dated the 5th October 1872.
PROVISIONAL SPECIFICATION left by the said Duncan McColl and
James Gillespie at the Office of the Commissioners of Patents, with
their Petition, on the 5th October 1872.
We, DUNCAN MCCOLL, Bricklayer and Furnace Builder, and JAMES
GILLESPIE, Master Slater, both of Paisley, in the County of Renfrew,
North Britain, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN FURNACES FOR THE CONSUMING OF THEIR SMOKE," to be as
follows, that is to say :-
1
This said Invention consists in constructing all steam boiler and
other furnaces with two or more fire-places, and in returning the

page_text: "
smoke produced in the whole, or in one or more of the fire-places
thereof; from the main outlet flue leading to the chimney through
and by the use of a pair of drawing and forcing fanners to and
through the flues leading to the front part of all the fire-places, these
flues being each controlled by an inlet valve or damper so as to allow
the said returried smoke to pass into and over the top of the hot fire
or fires which at the time are producing little or no smoke, all so as to
consuimic the said returned smoke produced in or mainly in the other
green or freshly charged fires. The fires being charged or supplied
with the fresh fuel alternately for this said returning and consuming
of the smoke from the other fires alternately and respectively, the
dampers of the return flues of the freshly charged fires being shut,
and those of the hot and bright fires opened at or near the same time,
and the main flue may be fitted with the usual damper leading to the
chimney placed behind the ſanners to be opened at starting the fires, or
otherwise as occasion may require; which improvements will prevent
the escape of all smoke, and save much fuel in furnaces so constructed
and fitted with them.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Duncan McColl and James Gillespie in the Great
Seal Patent Office on the 19th March 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we; DUNCAN
MCCOLL; Bricklayer and Furnace Builder, and James Gillespie, Master
Slater; both of Paisley, in the County of Renfrew, North Britain, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fifth day of October, in the year of
our Lord One thousand eight hundred and seventy-two, in the thirty-
sixth year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto us, the said Duncan McColl and James Gillespie, Her
special licence that we, the said Duncan McColl and James Gillespie,
our executors, administrators, and assigns, or such others as we, the said
Duncan McColl and James Gillespie, our executors, administrators, and
assigns, should at any time agree with, and no others, from time to time

page_text: and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United King-
dom of Great Britain and Ireland, the Channel Islands, and Isle of Man,
an Invention for "IMPROVEMENTS IN FURNACES FOR THE CONSUMING OF THEIR
SMOKE," upon the condition (amongst others) that we, the said Duncan
McColl and James Gillespie, our executors or administrators, by an in-
strument in writing under our, or their, or one of their hands and seals,
should particularly describe and ascertain the nature of the said In-
vention, 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 Duncan McColl and James
Gillespie, do hereby declare the nature of our said Invention, and in
what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement in writing, reference
being had to the accompanying Sheet of Drawings, and to the letters
and figures marked thereon, that is to say :-
Our said Invention consists in constructing all steam boiler and
other furnaces with two or more fire-places, and in returning the
smoke produced in the whole, or in one or more of the fire-places
thereof, from the main outlet flue (usually leading to the chimney
through or by the use of a pair of drawing and forcing fanners) to
and through flues leading to the front part of all the furnaces or
fire-places, these flues being each controlled by an inlet valve or
damper so as to allow the said returned smoke to pass into and over
the top of the red or hot fire or fires which at the time are producing
little or no smoke, all so as to consume the said returned smoke
produced in or mainly in the other "green" or freshly charged fires
or furnaces. The fires being charged or supplied with the fresh fuel
alternately for this said returning and consuming of the smoke from
the freshly charged fires alternately and respectively, the dampers of
the return flues of the freshly charged fires being shut, and those
of the hot bright burning fires opened at or near the time the fresh
fuel or coal is charged or supplied, and the main flue may be fitted
with the usual damper leading to the chimney (placed behind the
fanners) to be opened at starting the fires, or otherwise less or more
as occasion may require; which improvements will prevent the escape

page_text: of all smoke, and save much fuel in furnaces so constructed and fitted
with them.
And in order that the full nature, novelty, and mode of performing
our said Invention may be properly understood, we shall now proceed
to describe the several Figures on the Sheet of Drawings which we have
hereunto appended for the purpose of showing the best modes and
means we are at present aware of for putting our said Invention into
practice; the same reference letters and numerals indicating the same
or like parts in all the Figures.
3
..
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...
Figures 1 and 2 are a longitudinal and a front transverse vertical
section respectively, taken on the lines 1 1 and 22 in the plan
and horizontal section, Figure 4, taken mainly on the rectangular line
3 in Figure 2, all of a set of four double fluc Cornish boilers
with the fire-grate partly in the brickwork in front and partly in the
flues themselves, constructed in accordance with and illustrative of one
modification and adaptation or application of our said improvements as
applied thereto; and Figure 3 is a longitudinal section of the same
taken on the line 4 - 4 in Figure 4, showing one of the new taking
back or reversing side flues f', preferably placed below the ordinary
forward conducting side flues E; while Figure 5 is a back transverse
5 in Figure 4, to
vertical section taken on the irregular line 5
show the arrangement of back flues more clearly than seen in the other
Figures.
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-
-
Referring to this arrangement shown in Figures 1 to 5, the con-
struction of each boiler A and arrangement of the fires or furnaces B, B,
and main flues C, C, led down into the back end D' of the central
flue D in the brickwork below the boiler, led back and up the angled
flues D into the front end of the side flues E, E, led forward into the
brickwork close along the sides of the boiler until they join into one
behind the dipping flue D' at E', where they enter direct by the opening
or port E controlled by the damper E into the flue F, common to all
the boiler furnaces, and which lead direct into the main flue G of the
chimney controlled by the damper G' are all thus far substantially of a
usual construction, except that by these our improvements the side flues
E, E, of each boiler are made with the dipping flue and port e, controlled
by the damper E2 of these flues, so as also to lead into a main common
flue below the flue F, but leading back through the side flues ƒ³‚ƒ³,

page_text: close below the bot upper flues E, E, to the front of each furnace grate
B, B, by vertical flues f" controlled by the dampers f³, f³, a little in
front of the boilers A, where the brickwork and fire-grate are continued
out a little further than usual for obtaining room for these ports and
dampers which are for returning the black or unconsumed smoke
and gaseous products of combustion from the "
"
green or freshly
charged fuel and fires to and through the strong red fires for the time
being, or while they are so, all as herein-before described by the im-
provements of this Invention, or as will be fully understood from the
Drawings and the following description of the mode of firing and of
working these improvements, either with or without fanners for pro-
ducing a draught in the return flues.
In this arrangement shown with four boilers A we charge or supply
the fuel to the furnaces B, one half of these at a time intermittently
and alternately with the other half, when the fuel of the last charged
fires has burned down to a red or smokeless state, so that the smoke
created in the freshly charged fires, preferably those of the alternate
furnaces and boilers, say of the ones A, B, marked 1 and 3 in Figures
2 and 4, indicated as black with the fresh fuel, would return through
or over the fires B of the furnaces and boilers 2 and 4 respectively of
the same Figures, indicated as red and in full combustion without giving
off black smoke, so as to consume or utilize and burn all the smoke
from the freshly charged furnaces respectively, and also alternately and
respectively as charged and described. This returning of the smoke
is effected by shutting down the front dampers (as f², f*), of the fresh
or newly charged fires (as 1 and 3), and opening those (as f, ƒ³), of
the red fires (as 2 and 4), and also at the same time raising the dampers
(as E, E), so as to open the lower port e into the return flues f, ƒ¹, and
close the ports E", E", (leading direct to the outlet flues F, G, to the
chimney) of the freshly charged fires 1 and 2, and simultaneously
lowering the corresponding dampers (as E³, E2), so as to close the
ports e and open the ports E" of the red or hot fires 2 and 4, through
which the smoke of the other fires is being consumed for the time being,
and so that the products of combustion not consumed from the whole
of the furnaces pass out through the ports E", E", of the hot fires
finally regulated by the damper G' in the flue G leading to the chimney,
which is shown about half open in Figure 1, all as indicated by the

page_text: arrows in the several Figures. Supposing the furnaces of the first and
third boilers to be those freshly charged for the time being the several
dampers and E being actuated by their ropes or chains and E,
and counterbalancing weights and E³ respectively, being brought and
worked near the front of the furnaces B to be conveniently worked by
the fireman after charging the furnaces with fuel, and that a fan
It
blast may be used to assist the return of the smoke when desired.
will be understood and seen also that a set of two, three, or other
number of boiler furnaces could be arranged to act in like manner as
described and shown in accordance with these our said improvements,
as by charging the furnaces of one or more of the boilers at a time,
and making the smoke from these pass over or through only one, two,
or more of the red furnaces as might be convenient or desired; and
that further, where there was only one boiler the same returning and
burning of the smoke could be effected in accordance with our improve-
ments by keeping the flues from each fire B and tubes C separate by a
division up the centre of the flues D and D', and having a damper E'
on each of the side flues E where they enter the main and return
flues F and ƒ (instead of joining these flues with one at E, e), and
raising one damper and lowering the others, as each of the furnaces
was charged alternately and respectively otherwise all substantially as
described in reference to the Figures shown on the Drawings; and
although these improvements have only been described and shown
as applied to the double flue and land boilers, it will be evident they
are also applicable to furnaces of multitubular and marine steam boilers,
and other heating furnaces where two or more fires can be worked con-
jointly, as described, by new return flues and dampers; the last or
ordinary damper G' in the flue G being actuated as usual by hand or
otherwise so as to regulate the escape of the carbonic acid gas or other
unconsumed products of combustion direct to the chimney.
Having now described and particularly ascertained the nature of our
said Invention, and the manner in which the same is or may be used
or carried into effect, we would observe in conclusion that we do not
desire to restrict ourselves to the precise details or arrangement of
furnaces and boilers to which we have shown our improvements applied
in the accompanying Drawings, as many variations may be made there-
from without departing from the main or essential features of our said

page_text: Invention, but what we believe to be novel and original and therefore
desire to claim as the Invention secured to us by the herein-before in
part recited Letters Patent is, the conducting of the smoke from a freshly
charged fire or fires through return flues for that purpose, to and over
the hot fire or fires of steam boiler and other heating furnaces having
two or more fires or furnaces, all substantially as herein described and
shown in the accompanying Drawings.
In witness whereof, we, the said Duncan McColl and James
Gillespie, have hereunto set our hands and seals, this Fifteenth
day of March, in the year of our Lord One thousand eight
hundred and seventy-three.
Witness,
JOHN THOMSON,
Patent Agent,
62, Buchanan Street;
Glasgow.
DUNCAN MCOLL. (L.S.)
JAMES GILLESPIE. (L.S.)