CERTAIN IMPROVED MEANS OF PRODUCING HEAT FROM THE COMBUSTION OF CERTAIN KINDS OF FUEL
Year: 1841

page_text: MARCH'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
COLLEY MARCH, of Barnstaple, in the County of Devon, Surgeon, send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Eighth day of June, in the fourth year of Her reign, did for.
Herself, Her heirs and successors, give and grant unto me, the said James
Colley March, Her especial licence, full power, sole privilege, and authority,.
that I, the said James Colley March, my exors, adiñiors, and assigns, or such
others as I, the said James Colley March, my exors, adiñors, or assigns,
should at any time agree with, and no others, from time to time, and at all.
times during the term of years therein expressed, should and lawfully might
make, use, exercise, and vend, within England, Wales, and the Town of
Berwick upon Tweed, and also in all Her Majesty's Colonies and Plantations
abroad, my Invention of "CERTAIN IMPROVED MEANS OF PRODUCING HEAT FROM
THE COMBUSTION OF CERTAIN KINDS OF FUEL;" in which said Letters Patent is
contained a proviso, that I, the said James Colley March, shall cause. a
particular description of the nature of my said Invention, and in what manner
the same is to be performed, to be inrolled in Her said Majesty's High Court
of Chancery within six calendar months next and immediately after the date
of the said in part recited Letters Patent, as in and by the same, reference
being thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
James Colley March, do hereby declare that the nature of my said Invention,.

page_text: and the manner in which the same is to be performed; are fully described and
ascertained in and by the following statement thereof, reference being had to
the Drawings hereunto annexed, and to the figures and letters marked
thereon, (that is to say):-
In producing the combustion of various bituminous coal, in consuming it
when used for evaporating and other purposes in furnaces, it is usual so to
construct the furnaces or fire-places that the atmospheric air shall pass between
fire bars and amongst the coal placed thereon; but when making coke, by
bringing coal into a state of combustion, no fire bars are used, the combustion
being obtained by the passage of air over the surface of the coal. Now, my
Invention consists in effecting the combustion of various descriptions of coal by
impelling the requisite quantity of atmospheric air in streams downwards so as
to cause it to impinge on the surface of such fuel, by which means such fuel
and inflammable gases evolved during combustion are more advantageously
consumed and a saving effected. Figure 1, Sheet A, is the front elevation of
a stationary boiler, to which is applied apparatus for consuming fuel according
to my Invention. a, the stationary boiler; b, the receptacle for coals, which I
denominate a coal chest; c, a main pipe, by which a blast of air is conveyed
through tubes placed within the boiler, conducting the blast of air on to the
surface of the fuel through the bottom of the boiler, such blast of air being
obtained by any convenient mechanical means, as is well understood. Figure 2
is a transverse section through G, H, Figure 3. Figure 3 is a side elevation
of Figure 1; Figure 4, a longitudinal section through A, B, Figure 1;
Figure 5 is a horizontal section through C, D, Figure 3; and Figure 6, is a
horizontal section through E, F, Figure 3; 0, 0, (Figures 2, 4, and 5,) are
horizontal tubes, d, d, perpendicular ones; k, k, short metallic tubes projecting
from the bottom of the boiler; e, is a plate connected with two racks, f, f, by
which the coal is progressively raised as part becomes consumed; 9, g, are
water spaces enclosing the burning fuel; h, h; are two guides for retaining the
plate e in its proper position; i, i, are two rollers, to keep the rack in gear.
Figure 3 shews the gearing connected with the racks f, f, by which the plate e
is raised; a ratchet wheel, indicated by the dotted line at (m), retains the racks
in any positions to which they may be raised. Figure 6 shews the plan of
the water spaces g, g, and of the plate e, round the edge of which plate e,
. moveable slips of iron 1, 1, are hinged, so as to touch the sides of the chest bat
all times, notwithstanding the sides of the chest are inclined, causing the chest
to be larger at top than at the bottom, which figure of chest facilitates the
raising of the fuel therein, it having been found that the coal, when the sides
of the chest are vertical, are liable to become jammed, and frequently to such
"

page_text: an extent as to be immoveable, but by this means the difficulty is surmounted.
It will be found sufficient to construct the top one inch larger in width and
breadth than the bottom in a coal chest. four feet in depth, which I have ascer-
tained to be a good proportion..
The two triangular guides, h, h, by being parallel their whole length, project
more from the plates of the coal chest at the top than at the bottom, and in
proportion to the difference between the breadth and width thereof. The plates
forming the coal chest (which I prefer of cast iron) have flanches (n) upon
their upper and lower edges; by the former they are affixed to the boiler, and
the latter rest upon brickwork. The slips or narrow plates 1, 1, are added to
the plate e, for the more.complete retention of coal or fuel as the plate ascends
into the wider part of the coal chest; such slips or narrow plates not being
absolutely necessary, I prefer water spaces, 9, 9, constructed in the manner
shown in the Drawing; but when it is desired to form a fire-place of a similar
shape, fire brick may be used. The horizontal tubes, o, o, and the perpen-
dicular ones d, d, may be conveniently constructed of brass or copper, and
fixed in the boiler plates by rings, in the manner already practised. In the
making of tubular flues of locomotive steam boilers, and which is well under-
stood, short iron tubes, k, k, project from the bottom of the boiler, to allow
sufficient space for the process of combustion, and these tubes may be made to
fix in the vertical tubes d, d; but I prefer the construction shewn at Figure 9,
Sheet D, where they are retained in their places by two or three threads of a
screw on their upper ends, whilst the perpendicular tubes within the boiler are
fixed by rings containing corresponding worms. Two fire doors will be found
more convenient than a single one, which should be lined with fire brick.
Figure 1, Sheet B, is a side elevation of part of a locomotive boiler, with
apparatus applied for carrying out my Invention, and also a longitudinal section
of a fan, herein-after mentioned. a, the boiler; b, the coal chest; c, the main
pipe, conveying a blast of air into the blast box p, which box covers the per-
pendicular tubes shown in the sections Figures 2, 3, and 4. Figure 2 is a
longitudinal section through G, H, Figure 3. Figure 3 is a transverse section
through C, D, Figure 1. Figure 4 is a horizontal section through A, B,
Figure 1, and of the fan through E, F, Figure 1; and Figure 5 is a plan of
the coal chest b, and plate e, which plate is raised by two screws r, r, one of
which is a right, and the other a left hand screw, working in the plate e, and
amongst the coal within the coal chest b, by turning the wheel s, which works
two bevilled wheels t, t, with which the cog wheels v, v, attached to the screws
are made to elevate the plate e. The description of screw preferred by me is
shewn in Figure 10, Sheet D. In order to allow of a ready access to the long

page_text: tubes commonly fixed in the body of locomotive boilers, I recommend a space w,
to be left between the ends of the long tubes and the coal chest, at the bottom
of which space there is a man-hole, shewn by the red line at æ, closed by a
door (y) opening downwards, proteeted with fire brick. Through the man-
hole any dust or cinders carried over the water bridge z, may be withdrawn.
The fan a¹, can be conveniently placed in the space usually occupied by water
in the tenders of locomotive engines. The fan a', by which the blast is
produced, is worked by an endless strap b', passing over a flanch c¹, affixed to
the inner side of one of the wheels of the tender. In order that the blast shall
not be allowed to cease upon the reversion of the engine, I place within the
fan a metallic ring d', moving easily against the internal circumference of the
circular part of the case; to this ring is attached a lever e', moving through a
slot in the circumference of the case of the fan, by which lever the ring is
moved over a part of the internal circumference of the case. When the engine
is working in the common direction, the lever is in the situation represented in
the Drawing, and then the blast passes through the upper channel f', into the
main pipe c, the metallic ring shutting off the communication with the under
channel g; but when the lever is raised to the position indicated by the dotted
lines, the ring opens the channel g', shutting off at the same time the upper
channel f. Leather is applied at h', to connect the mouth of the fan with the
main pipe. The blast is regulated or entirely shut off by the sliding plate j¹.
It may be remarked, that the fan can, by means of suitable mechanism, be
worked by hand previous to starting the engine, but I prefer working the same
from a stationary locomotive, or a fixed engine, which can be readily provided
at most stations. The Figures in Sheet C, represent the application of my
Invention to a reverberatory furnace, suitable for various useful purposes.
Figure 1 is a side elevation; Figure 2 is a longitudinal section through C, D,
Figure 3; Figure 3 is a front elevation, and Figure 4 is a transverse section
through A, B, Figure 1, of that part of the furnace to which my Invention is
to be applied. The arch above the fire may be constructed of fire brick, formed
with proper apertures for the perpendicular tubes d, d. This arrangement of
tubes may be adopted in some instances, but when the required degree of heat
is very considerable, I then dispense with the metallic tubes d, d, and .form
blast passages by simply making proper perforations in the roof over the fire
place. Instead of a door or doors, I prefer a block of fire brick or fire stone
raised by chains, as is clearly shewn in Figure 3, to close the mouth of the
furnace. The blast is conveyed into a blast box p as in the case of the loco
motivė boiler. The bottom of the coal chest and the accompanying gear is no
shewn in these Figures, because they are similar to those shewn in Figures 1

page_text: 2, 3, and 4, Sheet A, and because also it is evident that the coal chest may
be extended to any convenient depth. The Figures 1, 2, and 3, on Sheet D.
show the application of my Invention to marine boilers. Figure 1 is a front
elevation, partly in section, of a marine boiler. Figure 2 is a longitudinal
section through A, B, Figure 1. Figure 3 is a tranverse section through C, D,
Figure 1. The section in Figure 1 is taken through F, F, Figure 2. k¹ is
a pipe connecting the main blast pipe with the blast box p; 9, 9, the water
spaces. In the connecting pipe ¹, a throttle valve is placed, worked by the
rod 7, and fixed in the required position by the thumb screw m¹. By means of
this valve the blast is governed. The plate e is raised by two screws (one right,
the other left hand) as in the case of the locomotive boiler; but instead of these
working in the plate and amongst the fuel arms n¹, n', project from the bar o¹ to
which the plate is fixed, and these armis contain the nuts in which the screws.7, 7,
work. The front arm contains two nuts, in order to steady the plate. The screw
beneath the fire-doors is actuated by the bevilled gear t, t, worked by the lever p¹,
and through the shaft q', working the back screw. In this modification the
guides h, h, shown in the former sheets, are not required. The front arm of the
bar o', forms a wedge at , moving the slides s', s', in its ascent. These slides,
better shewn at Figures 4, 5, 6, and 7, are so applied that the small pieces of
coal which would otherwise fall through the slot t', are retained; s, s², are stops
to the slides s'. The guides v¹, v¹, keep the slides in a parallel position; w¹, w¹,
are leading pieces; a, a, are clearance holes; and y', y', clearance passages,
the upper passages being inclined inwards, and the under outwards, that
dirt may more readily pass off. The guides ¹, v, are cut away underneath, as
shewn at Figure 8, to allow the part from 1, Fig. 6, to move as far as a, Fig. 8.
Figure 5 and 7 are edge views; and Figure 6 is a plan of the under side of one
of the slides. Figure 9 shows the manner of fixing the perpendicular tubes d, d,
and the short pipes k, k. Figure 11 is a side view of the receptacle for the
live fuel when the coal chest requires to be recharged, and also of the shoot for
filling the chest. A part of the receptacle 2, overlaps the water space 9; and
rods ², c, are attached to the receptacle or are suspended from eyes on the
boiler. The sloot d², covers the top of the receptacle, and is prevented from
sliding by the projection e. In order to light the fine upon the surface of the
coal, small pieces of sticks or chips are placed under one of the perpendicular
tubes d, d, and then a portion of straw or shavings, which may be lighted in the
hand, should be placed upon the sticks or chips; a moderate blast will be suffi-
cient to ignite a portion of coal which may then be pushed under the next tube,
and so on, from tube to tube, till in about five minutes the whole surface may
be kindled into a glowing fire; but ignited coals may be used for lighting when

page_text: at hand, and the process conducted as already described. I have ascertained
that about nine hundred and seventy-five cubic feet of atmospheric air are
required by my mode of combustion, to evaporate one cubic foot of water. The
size of the orifices of the tubes k, k, which transmit the blast upon the fuel,
may be various, and range from three quarters. of an inch to an inch and a
quarter in diameter. As a general rule, I will state that sixteen such tubes,
each with an orifice an inch in diameter, may be estimated as a fit proportion
to evaporate twenty cubic feet of water in an hour, the quantity of water
evaporated will be in proportion to the quantity of atmospheric air impelled
upon the burning fuel; in this case, the boiler should have a proportionate
extent of surface, or a loss of heat will ensue. It may, however, be stated that
I have found a rapid and vivid combustion most advantageous. The blast
tubes k, k, I place at distances of nine inches apart from each other, but the
distance may be moderately increased or diminished; but I have found nine
inches a good distance. The combustion of the coal may be continued till the
quantity resting upon the plate e is not more than six or eight inches in depth,
which may be then drawn out into an iron receptacle 62, Figure 11, Sheet D,
constructed so as to be occasionally attached to the mouth of the fire-place.
The iron shoot d³, Figure 11, Sheet D, may then be placed over the iron
receptacle, and a sufficient quantity of coal may be placed upon the iron shoot
and pushed into the fire-place. The coals contained in the receptacle should
then be returned to the fire-place upon the fresh coal, and the process of refilling
is thus speedily completed. The coal used in my process should not contain
knobs much larger than an orange, and it should be mixed with a sufficient
quantity of small coal to fill up the interstices; in the course of working, depres-
sions on the surface of the ignited fuel gradually take place under the blast tubes,
and form hollows, which should be occasionally levelled with an iron rod or rake,
and if
any clinkers are formed, they are found at the bottom of these hollows,
and are easily removed by one end of the iron rod being crooked. When these
hollows are levelled, portions of raw coal are sometimes mixed with the ignited,
and for an instant smoke is occasioned; but with a little care the levelling may
be effected without producing any smoke; and it will in general be found that
in the process of combustion herein described, no smoke is produced, except as
here stated. It may sometimes be required to produce much flame, and for
this purpose I convey through small tubes combustible fluid into the horizontal
pipes o, o; these tubes are provided with openings which correspond with the
descending blast pipes d, d, and thereby transmit the combustible fluid, such as
coal tar, into the hollows. A reservoir should be provided, and placed sufficiently
high to allow the fluid to flow through the tubes, which may be provided with

page_text: regulating cocks. I would, however, remark that I make no claim to the
introduction of combustible fluids, they having been used before. And I would
also remark, that in stating the certain kinds of fuel referred to in the title of
my Patent to be the various description of coal, I except anthracite, as I have
not found it to burn well by the above described means of applying blasts of
air. And I would also remark, that when the blast tubes pass through a boiler,
I sometimes propose to use tubes separate from the boiler, passing through
other tubes affixed to the boiler, by which means I avoid abstracting heat from
the steam and from the water in the boiler, for I consider it prejudicial to
abstract heat from the steam and water by the blast of air so used.
Having thus described the nature of my Invention and the best means with
which I am acquainted for carrying the same into effect, I would remark,
that I lay no claim to the parts separately, and it will be evident that the
furnaces and apparatus may be varied without departing from my Invention,
so long as the peculiar mode of consuming coal be retained, which, as above
described, consists of a mode of obtaining combustion of such coal by causing
streams of air to be blown and caused to impinge on the upper surface of such
fuel, and without passing through the general body of coal below the ignited
surface, as herein explained.
In witness whereof, I, the said James Colley March, have hereunto set
my hand and seal, this Sixth day of December, in the year of our Lord
One thousand eight hundred and forty-one