IMPROVEMENTS IN FIRE-PLACES
Year: 1873

page_text: PROVISIONAL SPECIFICATION left by Walter Knaggs at the Office
of the Commissioners of Patents, with his Petition, on the 10th
February 1873.
I, WALTER KNAGGS, of 5, Euston Grove, Euston Square, in the
County of Middlesex, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN FIRE-PLACES," to be as follows:-
In the ordinary fire-grate the heat from the front or bars only is
radiated into the room, that generated at the back and sides being
entirely lost by passing up the chimney.
I propose to economise fuel by utilising the heat so lost. To do this
I propose to burn the fuel or heating gas in a grate set at a distance
from the walls of the fire-place. I propose that this grate should by
preference be constructed of an oval shape with bars all round it or
nearly so. It is evident that such a grate whether fed with solid fuel or
heated by gas acting upon incombustible materials would present a
glowing face on all sides, the most favorable condition for giving off
heat. The heat emanating from the front of such a grate would of
course be thrown directly forward into the room, while that given off

page_text: place.
I propose to intercept and throw forward into the room such heat
given off from the back and sides by placing a reflector or reflectors
between the grate and walls, such reflectors to be constructed of metal 5
or any other suitable reflecting material.
In order to prevent the waste of fuel consequent upon feeding the fire
from the top I propose to supply fuel to the fire from below. I propose
to do this by having a chamber of a suitable depth below the grate,
having in it a movable bottom or plate capable of being raised or 1
lowered at pleasure. This bottom or plate should work freely within
the chamber below the grate, and should be provided with two or more
projections which should work and project through as many vertical
openings or slots situated on the sides of the chamber.
I propose to place opposite to each of these slots a vertical screw, so i
that the projections upon the movable bottom may enter the thread of
the screws, and in this way the screws being connected by means of
cogged wheels, so that one being turned will act upon the other or
others, the bottom or plate may be raised or lowered at will.
In order to replenish the chamber with fuel without disturbing the
fire, I furnish the chamber with two openings extending half way
through the front half of the chamber, one just below the bottom fire-bar
and just clear of the worm of tho screw, and the other at the bottom of
the chamber, and both secured by a shifting cover or door.
When the bottom and the whole of the fuel has been screwed and
raised up to the bottom of the grate and the screw no longer acts upon
it, I open the opening at the bottom of the chamber and insert a
duplicate movable bottom or plate similar to the one that is at the top,
I then fill up the chamber with fuel by means of another opening
guided by a door or cover, and situated in the upper part of the
chamber. I then raise the bottom plate with the fuel upon it by
turning the screws until the fuel comes in contact with the top plate on
which the burning fuel is situated, and then I withdraw the top plate by
means of the upper opening, and the burning mass comes immediately
in contact with the fresh fuel, which is then ready to be raised into the
grate as required. I provide round the grate a projecting guard or

page_text: fender to catch any thing that may fall from it, and another round the
bottom of the chamber to catch anything that may fall from it also, and
I use in the grate either vertical or horizontal bars, or a combination of
the two, or diagonal as I may prefer, and I protect the slots in the back
and sides if necessary by suitable coverings or doors or slides to exclude
the access of air, and prevent the falling out of dust, &c., and the spaces
between the bars may be filled in with a transparent non-combustible
material such as talc if desired.
The chimney may be either a continuous pipe from the upper portion
of the stove or grate, or it may hang over it like a funnel, and the
funnel part may be made transparent to allow the heat from the surface
of the glowing fuel to radiate through it. This stove pipe may either
work directly into the ordinary chimney of the house from below, or it
may pass directly upwards within the room and communicate with the
ordinary chimney by means of an opening in the brickwork just below
the ceiling. In the latter case it would not only give off additional heat
to the chamber, but it would assist in ventilation by enabling the over
heated and vitiated air of the room to pass into the chimney through
suitable valves or shifting gratings to be placed in the opening in the
brickwork through which the stove pipe enters.