IMPROVEMENTS IN FIRE-GRATES
Year: 1873

page_text: LETTERS PATENT to John Gratrix, of Preston, in the County of
Lancaster, Engineer and Ironfounder, for the Invention of
"IMPROVEMENTS IN FIRE-GRATES."
Scaled the 29th August 1878, and dated the 8th March 1873.
PROVISIONAL SPECIFICATION left by the said John Gratrix at tho
Office of the Commissioners of Patents, with his Petition, on the
8th March 1873.
I, JOHN GRATRIX, of Preston, in the County of Lancaster, Engineer
and Ironfounder, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN FIRE-GRATES," to be as follows:-
My Invention consists of certain improvements in and applicable to
fire-grates for domestic and other purposes, whereby I obtain a greater
amount of heat from a given amount of coal than by any other process
yot known.
I fix in the sides of an ordinary fire-grate, or in the sides and round
the back a series of vertical cold air chambers open at the bottom
and communicating at top with an head chamber going across or right

page_text: round, and open at each end in front of the grate or any other convenient
place, to such openings, if desirable, I fix a pipe or tube and by such
means can and may carry it to any part of a room or into any part of
the building required. I may dispense with a number of chambers and
effect the same purpose by one common chamber taking my heated t
air away in the same way as before stated. A current of air will pass
through the vertical chamber or chambers upward to the head chamber,
such air being heated on its passage becomes highly rarefied from which
its tendency is to rise, thereby a continued current is passing through
these tubes or tube to head chamber and from thence to wherever it 1
may be required.
I have likewise a portable apparatus which I can place on the top in
front of a fire consisting of a series of draught chambers communicating
as before with head chamber from which the heated air may be con-
ducted, in some cases I make a cold air chamber under the grate or 1
communicating with the outer atmosphere to my vertical chambers.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said John Gratrix in the Great Scal Patent Office
on the 8th September 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN 2
GRATRIX, of Preston, in the County of Lancaster, Engineer and Iron-
founder, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eighth day of March, in the year of our Lord
One thousand eight hundred and seventy-three, in the thirty-fifth 2
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said John Gratrix, Her special licence, that I,
the said John Gratrix, my executors, administrators, and assigns, or
such others as I, the said John Gratrix, my executors, administrators,
and assigns, should at any time agree with, and no others, from time 3
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 FIRE-GRATES,” upon

page_text: the condition (amongst others) that I, the said John Gratrix, my
executors or administrators, by an instrument in writing under my, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the
samo 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 John Gratrix, 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 :-
The object and intention of these improvements are to reduce the
consumption of coals for domestic and other purposes, likewise to give
greater heat and facilities for cooking, and to improve ventilation of
rooms or buildings.
Herewith I annex two Sheets of Drawings, on which the several parts
are marked by corresponding letters of reference.
Figure 1 is a front elevation of a sitting room, parlour, drawing room,
or office grate, to which my improvement is fixed; Figuro 2 is a side
view of the same; Figure 3 is a plan; Figure 4 is a sectional clevation
through A, B, of plan, shewing vertical tubes from bottom into air
chambers at top of fire-back, with four air pipes for connecting air pipes
to any room or chamber in the building; Figure 5 is a plan of bottom
grate, on which is a circular moveable raking grate, carrying in the
centro a dome-topod perforated chamber for carrying the air into the
middle of the fire.
n'
. A, A, in Fig. 1 is a grate front, from which projects vertical bared
grato B, quadrant or other shaped; C is a fire-back of fire-brick or other
equivalent, with vertical chambers D, going from bottom chamber E to
top chamber F. These chambers go round. the fire-back in a circular
shape; E, chamber recieving the cold air, cither from the room at a, a,
or by pipe from the outside of the building. In front of grate A
communicating with the top chamber F I fix two face valves G
to admitt air into the room where the grate is fixed (when required).
II, in Fig. 1, is an indicating finger fixed on a spindle u, which goes
through the up-take of the fire-place, on which is fixed a wing throttle
valve, dotted and marked I, to regulate the up-take draught in chimney.
.

page_text: J, J, J, J, are four indicating fingers connected to similar small wing
valves in the four valve boxes K. In connection with and leading
from these boxes are pipes L, which may be carried into any parts of
the same room or into any other rooms of the building. It will thus be
seen that the air may be brought in from the outside of building by
pipe b, or from the inside of room by appertures a, a, or both.
The lower part of Fig. 4 and Fig. 5 shews section and plan of my
improved arrangement of bottom or fire-grates. Fixed to my front A
is the circular bottom grate M, perforated as convenience may dictate.
In the centre is a round hole c, into which fits pin d 1 of Fig. 4; this
serves as a swivel for the top grate N to work upon. This top grate N,
as shown in Fig. 3, is perforated and has on the top side a number of
small projecting conical peices which acts upon the bottom of the fire
and cleanses it by turning the handle O from side to side too and fro. In
the centre of this moveable plate I place a dome-toped perforated
chamber, which carrys the air into the middle of the fire, thereby con-
suming the smoke by a more perfect combustion. On the under side of
this moveable plate I fix a number of scrapers to cleanse from bottom
grate all dust or dirt.
Figs. 6 and 7 shews one arrangement in connection with cooking
range for culinary purposes.
A 1 is the ordinary range, B 1 my fire-back, as before described, but
the side, virtical, or top chambers are perforated with holes in the sides
as dotted, marked a, thus communicating with the flues E round
boiler and oven, which may be completely encircled by hot air if
desired. Underneath the oven I provide a small fire-grate C, on which
(when required) I use a small additional fire, fed through door D 1.-
Underneath such grate I place a sliding grate or damper of such shape
and size, as by drawing it, the fire-grate spaces are closed, and all air
from underneath excluded. It will be observed that this will only be
used when additional heat is required in the oven, at other times such
damper being drawn by handle 6 confines the hot air in the flues. I
place in convenient positions dampers or stop valves to cut off commu-
nication between fire-back chambers, and oven or boiler flues, so as to
get the benefit of the whole to the oven or to the boiler, or to cut off
from both oven and boiler, and carry such hot air through pipes c, c, to
any chamber in the building so desired; above this fire-back and with

page_text: tho‘inner circlo in a line with the outer circle of such back I placo
another back H of a similar construction, which for distinction I will
call a flame back, because it is mostly embraced by flame above the firc.
From the top chamber of this flame back I carry any number of pipes
to warm any number of chambers in the building, so arranged to suit
the requirements, that is, to enable the whole hot air to go into one
chamber, or to be distributed in as many as there may be.
Figs. 8 and 9 show side view and cross section of a domestic tubular
boiler forming the back of a cooking range. F 1, F 1, are two chamber
castings, on one side of each are cast sockets for as many tubes as may
be required or the size of the boiler demand; G1, G1, aro tubes of metal
cemented or otlierwise secured into the sockets of castings F1; H1, and
H 11, are feed and outlet pipes for water. These tubes may bo acted
upon directly by the fire or by the hot air from the chambers as before set
forth, or by both; hot water from this boiler may be carried to any
room in the building.
Figures 10 and 11 shew a front view and plan of a portable hot air
generater and diffuser. This simple article is made in construction
similar to my fire-backs, that is, with a number of chambers e, e, all
communicating with one common chamber at the back, as shewn by
dotted lines in Fig. 11.. Whenever the fire in a grate has got low or
to some degree incandent, yet. retaining a great ammount of heat which
I require to diffuse into the room without using more fuel, I place one'
of these portable articles on the fire with open holes fronting the room.
The cold air enters by the two outside holes e 1; into back chamber
dotted e 11, becomes heated, and returnes into the room again by the
centre passages e, e. The heat being usualy stronger in the middle of
the fire assists the natural current taken in on each side to drive it
with some force into the centre of the room.
Having now described my Invention, and several of the many ways
I use it, I wish it to be understood that I do not confine myself to the
preciso details I havo described and refered to, as many variations
may be made therefrom without deviating from the principle or main
features of my Invention, but what I claim as secured to me herein
is,―
First. The fire-back O, or its equivalent, substantialy as and for the

page_text: Second. The circular fire-grate and swivel bottom substantialy as and
for the purposes hercin set forth.
Third. The regulating valves substantialy as and for the purposes
herein set forth.
Fourth. The tubular boiler for domestic purposes substantially as and 5
for the purposes herein set forth.
Fifth. The portable generater and difuser, substantialy as and for
the purposes herein set forth.
In witness whereof, I, the said John Gratrix, have hereunto set my
hand and seal, this Sixth day of September, in the year of our 1
Lord One thousand eight hundred and seventy-three.
Witness,
JOHN LEWIS,
Engineer & Patent Agent,
Preston,
Lancashire.
JOHN GRATRIX (L.S.)