IMPROVEMENTS IN THE CONSTRUCTION OF STOVES
Year: 1856

page_text: LETTERS PATENT to George John Christian Erhard' Hald, of the City of
Manchester, Merchant, for the Invention of "IMPROVEMENTS IN THE
CONSTRUCTION OF STOVES."-A communication.
Sealed the 4th July 1856, and dated the 9th January 1856.
PROVISIONAL SPECIFICATION left by, the said. George John. Christian
Erhard Hald at the Office of the Commissioners of Patents,, with his
Petition, on the 9th January 1856.
I, GEORGE JOHN: CITRISTIAN ERHARD HALD, of the City of Manchester,
Merchant, do hereby declare the nature of the said Invention for IMPROVE
MENTS IN. THE CONSTRUCTION OF STOVES, to be as follows:-
The nature of this Invention consists in forming the interior of the stove of
bricks or other suitable material, within which a circular spiral flue is formed.
The products of combustion in ascending impart their heat to the interior
of the flue, thereby henting the bricks or other material of which the interior of
the stove is constructed. The exterior of the stove is composed of perforated
metal to which an ornamental appearance is given.
In cleaning out the flue of this improved stove; à ball of iron or other suit-
able material: is admitted at. the top, and allowed to roll down the flue.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George John Christian Erhard Hald in the Great Seal
Patent Office on the 8th July 1856.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
JOHN CHRISTIAN ERHARD HALD, of the City of Manchester, Merchant, send
greeting.
WHEREAS Hor most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Ninth day of January, in the year of our Lord
One thousand eight hundred and fifty-six, in the nineteenth year of Ier reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
George John Christian Erhard Hald, Her special license that I, the said
George John Christian Erhard Hald, my executors, administrators, and
assigns, or such others as I, the said George John Christjan Erhard Hald, 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 "IMPROVEMENTS, IN THE CONSTRUCTION OF STOVES,"
a communication from abroad, upon the condition (amongst others) that
I, the said George John Christian Erhard Hald, my executors or administra-
tors, by an instrument in writing under my, or their, or one of their hands and
scals, should particularly describe and ascertain the nature of the said Inven-
tion, 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 George John Christian Erhard Hald,
do hereby declare the nature of the said Invention, and in what manner the
same is to be performed, to be particularly described and ascertained in and
by the following statement, that is to say:―
The nature of this Invention consists in forming the interior of the stove of
bricks or other suitable material,-within-which a circular spiral flue is formed,
whereby a large amount of heating surface is obtained in a small compass;
also in the employment of a ball of iron or other material for cleansing such
flues.
And in order that this Invention may be fully understood, and readily
carried into effect, I will proceed to describe the means, as communicated
to me

page_text: Figure 1 is a front elevation of this improved stove; Figure 2 is a sectional
elevation of the same; and Figure 3 is a plan, also in section.
a is the fire grate surrounded by fire brick, and supplied with fuel through
the door 6; the flue c of this stove is formed of suitably shaped fire bricks,
marked d, d, each brick forming half a circle of the diameter of the stove, as
shewn best in Figure 3. The bricks when put together leave a spiral circular
flue of the size and angle shewn in Figure 2, but it will be apparent that by
altering the shape and dimensions of the bricks, any other size and angle of
spiral flue may be obtained. The spiral flue is in connection with the flue or
chimney that conveys the smoke away by the pipe e, shown in Figure 2. The
brickwork is surrounded by a casing of perforated metal or other material,
through which the heat enters the apartment to be warmed, and the upper
part of the spiral flue is covered by the cap f. The object of thus constructing
stoves is to obtain a large amount of heating surface within the limits of an
ordinary sized stove. The Drawing represents the spiral flue c as circular, but
it may be made in the form of an ellipse or other shape, and although the
blocks d are described as being made of fire brick, they may be made of
stone or any other material capable of resisting the action of the products of
combustion rising from the fire grate a. When the flue c requires cleansing,
the cap fis removed, and a ball of cast iron or other suitable material is intro-
duced at the top of the spiral flue, and allowed to roll down it, thereby loosen-
ing the soot adhering to the interior of the flue; when the ball has decended
to the bottom of the flue, it is again put in at the top, and this is repeated
four or five times, or until the soot is removed from the flue.
Figures 4 and 5 represent a mode of applying this improved stove in the
place of the ordinary fire grates. h, h, h, aro three stoves placed in recesses
in the wall, and one above the other, in the different apartments of a dwelling
house; the spiral flue of the uppermost is in communication with the flue i
placed immediately above it; the second stove is in communication with the
flue j, and the lowest stove is in communication with the flue k. The upper
part of the recess in which the stove stands is covered by an ornamental
screen of perforated metal or other material, as shewn at 2 in Figure 5, and
the lower part of the recess is left open to allow the fuel to be supplied to the
stove.
IIaving thus described the nature of this Invention, as communicated to me,
I wish it to be understood that I do not limit myself to the details herein
set forth, as the same may be varied without departing from the peculiar
character of the Invention; but what I do claim is, the spiral flue, marked c,

page_text: forming the interior of the stove, as shewn and as. described; and, secondly,
the mode described of cleansing the spiral flues of stoves.
In witness. whereof, I, the said George Jolin Christian Erhard Hald; have
hereunto set my hand and seal, this Fifth day of July, in the year of
our: Lord One thousand eiglit liundred and fifty-six.
Witness,
11. B. BARLOW,
Manchester:
G. J. C. ERHARD HALD. (L.S.)