IMPROVEMENTS IN ECONOMISING FUEL, AND IN THE MORE ECONOMICAL PRO-
Year: 1854

page_text: LETTERS PATENT to the Reverend William Renwick Bowditch, of Wake-
field, in the County of York, Clerk, Bachelor of Arts, for the Invention
of "IMPROVEMENTS IN ECONOMISING FUEL, AND IN THE MORE ECONOMICAL PRO-
PROVISIONAL SPECIFICATION left by the said William Renwick Bowditch'
at the Office of the Commissioners of -Patents, with his Petition, on the
10th January 1854.
I, the Reverend WILLIAM RENWICK BOWDITCH, of Wakefield, in the County
of York, Clerk, Bachelor of Arts, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN ECONOMISING FUEL, AND IN THE MORE ECONOMICAL
PRODUCTION OF LIGHT AND HEAT," to be as follows:-
These improvements have for their object the economisation of fuel as
applied to furnaces and boilers, and also to the obtainment of a greater amount
of light in lamps and gas burners than can be obtained by the arrangements at
present in use.
My Invention, as it relates to the construction of furnaces, consists in the
introducing the air necessary for the purposes of combustion through a flue
or flues, or series of coiled pipes or flués, situate alongside, or beneath, or other-

page_text: wise in connection with the furnace, and finally introducing the air upon the
burning fuel in a highly heated state at the end of the furnace nearest
the door.
In introducing the fuel into the furnace, I place the same, in the first place,
in an opening somewhat similar to that of a gas retort, and when it is partially
caked, by means of a lever, cause it to be gradually pushed back to the further
end of the furnace, by which means the fuel at that end of the furnace is
always in a state of red heat.
These improvements in economising fuel are equally applicable to the con-
struction of common fire grates-and to stoves, in which cases I form the grates
with a series of tubes or a chamber communicating with the air outside, or
with the interior of the room behind and alongside the fire (the ashpit being a
closed chamber).
This part of my Invention is also applicable to the economization of oil in
lamps and gas, which I effect by passing the air for combustion between two
glass chimneys, the outer of which is perfectly air-tight at its junction with the
gas pipe or burner, and the air consequently is caused to enter the top and
passes through a space at the bottom between the outer and inner glasses
directly upon the flame, which it reaches in a highly heated state.
further economisation of fuel, and to be used or not in connection with my
improved furnace, I propose to place inside boilers for the generation of steam,
a series of thin upright pieces of copper or other metal pointed at both ends,
and rising from the boiler plates into the water, by which means the water
is heated more rapidly and with a less amount of fuel than in ordinary
boilers.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed by
the said William Renwick Bowditch in the Great Seal Patent Office on
the 10th July 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, the
Reverend WILLIAM RENWICK BOWDITCH, of Wakefield, in the County of
York, Clerk, Bachelor of Arts, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of January, in the year of our Lord One
thousand eight hundred and fifty-four, in the seventeenth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Renwick Bowditch, Her special license that I, the said William

page_text: Renwick Bowditch, my executors, administrators, and assigns, or such others
as I, the said William Renwick Bowditch, my 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 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
"IMPROVEMENTS IN ECONOMISING FUEL, AND IN THE MORE ECONOMICAL. PRODUCTION OF
LIGHT AND HEAT," upon the condition (amongst others) that J, the said William
Renwick Bowditch, 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 William Renwick Bowditch, do hereby
declare the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Drawings and to the
letters and figures marked thereon (that is to say) :-
My said Invention has for it's object the economisation of fuel as applied to
furnaces and boilers, and also the obtainment of a greater amount of light in
lamps and gas burners than can be obtained from a given quantity of gas or
oil by the arrangements at present in use.
With reference to the construction of furnaces, I introduce the air necessary
for the purposes of combustion through a flue or flues, or a series of pipes
or flues, situated alongside, or beneath, or otherwise in connection with the
furnace, finally introducing the air upon the burning fuel in a highly heated
state at the end of the furnace nearest to the door. In introducing the
fuel into the furnace, I place the same, in the first place, in an opening
somewhat similar to that of the mouth piece of a gas retort, and when it is
heated there it is gradually pushed along to the further end of the furnace,
by which means the fuel at that end of the furnace is always in an incandescent
state.
These improvements in economising fuel are equally applicable to the con-
struction of common fire grates and to stoves, in which cases I form the grates
with a series of tubes or with a chamber communicating with the air outside
or with the interior of the room behind and alongside the fire (the ashpit being
a closed chamber). This part of my Invention is also applicable to the econo-
misation of oil as well as gas in lamps, which saving I effect by passing the air

page_text: for combustion between two glass chimneys, the outer one of which rests upon
a glass or metal bottom fitting air-tight. at its junction with the gas pipe or
burner, and the air is consequently caused to pass over the top of the outer
glass, to descend between that and the inner glass, and through a space at the
bottom to the flame, which it reaches in a highly heated state. As a further
economisation of fuel, and to be used or not in connection with my improved
furnaces, I propose to place inside the boilers for the generation of steam, a
series of thin upright pieces of copper or other metal, pointed at both ends and
joined together, and rising from the boiler plates or tubes into the water.
With this modification the water is heated more rapidly and with a less
amount of fuel than in ordinary boilers.
Fig. 1 on Sheet 1 of my Drawings represents a vertical section of my appa-
ratus for effecting a more economical combustion of gas for lighting purposes;
and Fig. 2 is a horizontal section of the same. A is a burner of the ordinary
argand description; it is screwed into the socket B of the branch pipe, and upon
a flange of this socket the glass disc or cup C rests, having a small washer above
it, thus forming an air-tight joint. Upon this disc or cup rests the outer glass
shade or cylindrical casing D. E is the ordinary chimney, which may be of
any convenient form, supported in the usual manner by the arms F, F. By
this arrangement the whole of the, air for supporting combustion must pass
down the annular space G, between the chimney E and the outer shade or
casing D, thereby becoming considerably heated before entering the flame; and
by this arrangement the gas is also heated prior to combustion. The pro-
portions which I prefer in this lamp are, that the diameter of the external
cylinder D should be double that of the burner, and the distance between the
bottom of the glass cup and the inner glass should be one and a half diameters
of the burner, and the distance between the top of the outer glass and the top
of the inner glass also one and a half diameters. Fig. 3, on the same Sheet
of Drawings, represents a partial section of a modification of the same prin-
ciple as applied to an oil lamp of the existing construction.
In this arrange-
ment, the outside shade A is curved slightly to give a more clegant appearance
to the general contour of the lamp. It may be composed of ground glass or
porcelain, and ornamented in any suitable manner according to the taste of
the manufacturer. A glass or metal disc B is fitted to the lamp immediately
below the air inlets C, so that all the air required to feed the flame must pass
down the annular space D, between the chimney E and shade A.; and it thus
becomes considerably heated thereby before coming in contact with the flame,
whilst it also heats the oil prior to its combustion. Fig. 4, on the same Sheet

page_text: of Drawings, represents a complete front elevation of a domestic stove grate,
with the addition of my improvements. Fig. 5 is a horizontal section of the
same through. the fire holding portion of the grate; and Fig. 6 is a vertical
section taken through the centre of the grate. The body of the grate A.. is
of the ordinary construction, with the exception that the ashpit B is closed in
front of the grate by the plate or vertical sliding door C, so that no air can
enter beneath the grate excepting by the means herein-after described. An
air aperture D, formed in the cheek of the grate, or at the back, or side, and
communicating with the external air and with the. heating chamber E, the
sides of which are composed of fire brick. This chamber entirely surrounds
the back and sides of the grate, and. becomes considerably heated by the fuel
contained therein. An opening or passage F," shewn in dotted lines in Fig. 5,
communicates with the heating chamber and ashpit, so that the air, which is
required to supply the lower portion of the grate, must previously pass through
the heating chamber E in. the direction of the arrows, whereby it becomes
considerably heated before entering the fire. If found desirable, the inlet
aperture.D may be furnished with a regulating valve to increase or diminish
the supply of air according to the amount of fuel in the grate.-
Fig. 1 on Sheet 2. of my Drawings represents a longitudinal vertical section
of a steam boiler and furnace, with my improvements connected therewith.
Fig. 2 is a transverse section of the same, taken through the centre of the
furnace bars; and Eig. 3 is a front or end elevation of the boiler and furnace.
A, A, are a series of vertical thin double pointed pieces of copper or other
metal placed in the interior of the boiler B, and resting upon the bottom or
heating surface thereof. These pieces of copper or heat conductors, as I term
theni, are held together by the curved strips of metal C and transverse pins ór
rivets.D, and as they are merely laid upon the bottom of the boiler and are
not attached: thereto, they may easily. be removed when the boiler requires
cleaning or repairs. Copper wire or other convenient means may be employed
to attach these pieces to the tubes, of. tubular boilers. The furnace is con-
structed on the principle herein-before, described, naniely, the heating of the
air in separate heating chambers before entering. the ashpit to supply combus-
tion. The front of the ashpit, in place of being open as is usually the case, is
closed by the brick-work E, and metal plate F, which erection extends over the
whole of the front of the furnace; a small aperture and door G is left for the
purpose of cleaning out the ashpit H-when requisite. The air for supplying
the furnace enters by the two apertures II, in the front of the brick work, or
at such other parts as may be convenient in practice, and it passes along the

page_text: heating flues or chambers J, J, whence it escapes in a highly heated state into
the ashpit by lateral passages or openings, one of which is shewn at K, in
Fig. 1. The heating chambers or flues J are formed in the interior of the
brick work or masonry which supports the boiler, and they may be lined with
fire brick, if thought desirable, the better to retain the heat. They extend to
the back of the boiler and then return to the front of the ashpit by the upper
return flues .or chambers J, J', which open laterally into the sides of the
ashpit, immediately below the grate bars. Dampers or regulating doors may
be fitted to the inlet apertures I, I, if found desirable, whereby the amount
of air supplied to the furnace may be regulated according to the will of the
engineer. Although the Drawings merely show the principle as applied to a
boiler with external flues, yet it may be equally well applied to boilers with
internal flues and furnaces, the air being heated by passing through tubes of
metal or fire clay in place of passages formed in the brick work. The dead
plate L is extended considerably beyond the front of the furnace to form a
species of closed retort, in which the newly supplied fuel is deposited previous
to its being pushed along into the furnace. By this means the fuel becomes
partially roasted in the retort, and the gases evolved therefrom having to pass
over the live coals or incandescent fuel in the furnace become ignited
and consumed thereby, thus in a great measure effecting the prevention of
.smoke.
Having now described and particularly ascertained the nature of my said
Invention, and the manner in which the same is or may be used on carried
into effect, I would observe, in conclusion, that I do not confine or restrict
myself to the precise details. or arrangements which I have had occasion to
describe or refer to, as many variations may be made therefrom without
deviating from-the principles or main features of my said Invention; but what
I consider to be novel and original, and therefore claim as the Invention
secured to me by the herein-before in part recited Letters Patent is,―
First, the application and use of an external shade or chimney for heating
the air supplying gas-lights or lamps as herein-before described and referred
to in Figs. 1, 2, and 3,.on Sheet 1 of my Drawings.
Second, the application and use of the air-heating chamber, in the manner
and for the purpose herein-before described, and referred to in Figs. 4, 5,
.and 6, of Sheet 1 of my Drawings.
Third, the application and use of thin double pointed or edged pieces of
copper or other metal, in the manner and for the purpose herein-before
described and referred to in Figs. 1 and 2 on Sheet 2 of my Drawings.

page_text: Fourth, the system or mode of heating the air for furnaces with internal or
external flues, as herein-before described and referred to in Figs. 1, 2, and 3,
on Sheet 2 of my Drawings.
In witness whereof, I, the said William Renwick Bowditch, have here-
unto set my hand and seal, the Eighth day of July, One thousand
eight hundred and fifty-four.
W. R. BOWDITCH. (L.S.)