AN IMPROVEMENT IN THE CONSTRUCTION OF STOVE GRATES CALCU- LATED TO PREVENT OR CURE SMOKEY CHIMNIES, AND POSSESSING OTHER ADVANTAGES OVER THE STOVE GRATES IN COMMON USE
Year: 1810

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Jonn
JUSTICE, of Dundee, in North Britain, Ironmonger, send grecting.
WHEREAS His present most Excellent Majesty King George the Third,
by His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Sixth day of March now last past, did give and grant unto
me, the said John Justice, His especial licence, full power, sole privilege and
authority, that I, the said John Justice, my executors, administrators, and
assigns, by myself and themselves, or by my or their deputy or deputies, servants
or agents, or such others as 1, the said John Justice, my executors, adminis-
trators, or assigns, should at any time agree with, and no others, during the
term of years therein mentioned, should and lawfully might make, use, exercise,
and vend, within England, Wales, and the Town of Berwick-upon-Tweed, my
Invention of "AN IMPROVEMENT IN THE CONSTRUCTION OF STOVE GRATES CALCU-
LATED TO PREVENT OR CURE SMOKEY CHIMNIES, AND POSSESSING OTHER ADVANTAGES
OVER THE STOVE GRATES IN COMMON USE;" in which said Letters Patent there is
contained a proviso obliging me, the said John Justice, by an instrument in
writing under my hand and seal, particularly to describe and ascertain the
nature of my said Invention, and in what manner the same is to be performed,
and to cause the same to be inrolled in His Majesty's High Court of Chancery
within four calendar months next and immediately after the date of the said
Letters Patent, as in and by the same, reference being thereto had, will more
fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
John Justice, do hereby declare that the nature of my said Invention is
described in manner following, that is to say:-
The stove grates of my improved construction are in appearance similar to
the register stoves in common use, but with the following additional con-
veniences or improvements :-The grate, or that part which contains the fire,
instead of being fixed and immoveable in its place between the outside cheeks,
as in the stove grates or register stoves in common uso, is moveable upwards
or downwards between the outside cheeks, so that it may be lowered or sunk
down even to the hearth when this is desirable, as where wood or turf is the
fuel principally to be employed, or may be raised or wound up to any height
desireable, and at the same time suitable to the inside opening of the front;
presenting in this power of being moved and placed at any required height the
great advantage of enabling the possessor so to adjust it as to cure or altogether
prevent that evil so very generally complained of, commonly called a smokey
chimney, for in most cases of smokey chimnies the evil, as is well known to
mechanics, may be remedied by bringing the top or lintel of the chimney down
to some certain distance from the grate, which shall be found to occasion precisely
that draught of air which is necessary to carry up the smoke. But the method
of remidy just mentioned would often be found to produce such a deformity
and want of proportion as would be unbearable in an elegant room, nor would
it be easy to adjust without various trials the height of the lintel precisely to
produce the effect intended. But thongh the top or lintel of the chimney can-
not always be conveniently altered to produce the effect wanted, the height of
the grate may with perfect convenience and without producing any unpleasant
appearance to the eye, and this is what I effect and what constitutes the prin-
cipal improvement in my said improved construction of stove grates. Another
improvement consists in giving motion by the same key that makes the
grate to ascend or descend, to two or more plates of metal fitted to the width
of the front, and when not in use kept out of sight behind the top of the
metal front (but those who prefer it may use a distinct key and arrangement
for this). These plates of metal answer the purpose of what is commonly
called a blower, and are in fact a blower differing in no respect from the
blowers in common use, excepting only that by being made in two or more
pieces instead of one, but I commonly employ only two; they are made to
slide one behind the other, so that the two occupy but half the space when up
that the blower would occupy if made of one piece (but if the lintel be broad
enough, the blower may be of one plate). This blower, by beginning to
descend after the grate in its ascent has reached a certain point, prevents the

page_text: necessity of raising the grate to such an inconvenient height (that is to
any height displeasing to the eye,) as would sometimes be otherwise necessary
in cases where the cure of a smokey chimney is difficult. From the descrip-
tion already given, any competent workman would be able to construct my
improved stove grate; for the methods of raising or lowering at pleasure any-
thing required to be moved by mechanical means may be varied without any
inconvenience, according to the fancy of the workman, being in fact infinite in
number; so that I do not rest my Invention on the particular methods or
mechanical contrivances that may be used to raise or lower the grate and the
blower, or either of them, but on the giving an ascending or descending motion
to the grate or to the grate and blower. But to enable any workman who
hereafter may be employed to construct similar stove grates, I shall describe,
as an example, one method of arranging the mechanical parts which I have
found in practice to answer very well. A slit should be cut in one of the out-
side checks, say, in the right-hand outside check, to allow a communication
between the fire-grate that is to be moved and the apparatus employed to
communicate the motion, the said apparatus being placed behind the cheek
out of sight (though this is not indispensibly necessary). Having fitted the
fire-grate, videlicet, the back and cheeks of the fire-grate to the back and
checks of the outer framing, a stout bar of sufficient strength to carry the
weight of the fire-grate must be made fast to the said fire-grate in such
manner and in such form that the said bar may come horizontally or nearly so
through the slit before mentioned, and then ascend perpendicularly behind the
outer check. On that side or face of the ascending part of the said bar which
is next to and parallel to the front of the grate, a rack should be cut (or a rack
may be attached securely to it). In this rack a pinion or small wheel should
work, and on the same axis that carries the said pinion or small wheel should,
be a wheel a little larger than the said pinion, with its teeth a little inclined to
receive motion from a worm, the outer end of the axis of which worm termi-
nates in the front of the stove grate, and is squared to receive the key employed
to wind up or lower the fire-grate, or the fire-grate and blower when a blower
is also attached to the stove grate. When this arrangement is completed, the
axis of the worm before mentioned will be horizontal, and at the same time
perpendicular to the face of the stove grate, and the axis of the wheel and
pinion before mentioned will also be horizontal but parallel to the aforesaid
face of the stove grate. As the grate is raised or lowered by motion communi-
cated, as has just been described, to an ascending or perpendicular bar attached
to it, so the blower is also lowered or raised by motion communicated to a bar
connected with it by an elbow through a slit in the cheek, but this last-men-

page_text: tioned bar descends perpendicularly instead of ascending like the one attached
to the fire grate. This descending bar on the side farthest from but parallel to
the front of the stove grate, has a rack, which falls on that side of the pinion
before named, which is opposite to the part working in the rack of the ascend-
ing bar before mentioned, that is, one pinion or small wheel works into the
racks of both, and of course when the descending bar is in action the motion of
the two racked perpendicular bars are, opposite and contrary, the one ascending
while the other is descending. But the descending bar is not furnished' with a
rack throughout its whole length, but only so much of it is so furnished as the
length of space through which the plates of the blower are to descend. The said
descending perpendicular bar is made fast only to one of the plates of the
blower, namely, that one which is to descend lowest; the other plate descends
by its own weight, and is furnished-with two or more pins which, coming
against stops placed at a suitable height, prevents its descending lower and
keeps it stationary, while the other attached to the descending bar continues to
descend by the motion communicated by the rack, till by- its descent and the
ascention of the grate, the two, videlicet the blower and the grate, are brought
close together (if need be), so.that, when in this position no air can enter the
chimney without passing through the fire. When the blower is wound up it
will be seen, from the foregoing description, that the ascending bar carries 'up
the lower plate only of the blower, but the lower plate is furnished with two or
more pins which, in its ascent, come against stops in the upper plate, by which
means the upper plate is also carried up, and both get out of sight behind the
top or lintel of the front of the stove. It is only necessary further to state that
the descending perpendicular bar is kept suspended when not in action (which
it is.convenient should be the case during some part of the rising of the fire
grate) by means of a lever, the pin or fulcrum of which is fastened to the
outside or back of the outer cheek. One end of this lever meets a pin project-
ing from the descending bar, while the other end is loaded with a counterpoise
able to sustain the weight of the descending perpendicular bar and the blower.
This lever is placed in such a position that the loaded end passes over the
horizontal arm by which the ascending bar is attached to the fire-grate, so
that when the fire-grate is down near the hearth the lever is in action, keeping
the descending bar at such a height that the rack on the said bar is disengaged
from the pinion, but when the firo-grate is wound up to a certain height (by
turning the key) the horizontal arm of the ascending bar before mentioned
reaches the loaded end of the lever, and in its ascent lifts up the said loaded
end, suffers the descending bar to descend, and thus brings its rack into action
with the pinion. A small bolt may be introduced to carry the weight of the

page_text: blower and its descending bar, by moving which bolt the fire-grate alone,
when this may be desirable, may be made to rise or fall without the blower
being brought into action. I have said nothing of fixtures or supports in
describing the before-mentioned apparatus. because they are precisely similar
to what would be employed in any other machinery to connect and support
parts similar to those which I have described as exemplifying the means that
may be used to give an ascending or descending motion to the fire-grate or fire-
grate and blower of my improved stove grate, which improved stove grate I
mean to distinguish on account of its property of suffering the fire-grate to be.
raised and lowered by the name of the Patent Metastatic Stove Grate.
In witness whereof, I, the said John Justice, have hereunto set my hand
and seal, the Nineteenth day of June, in the year of our Lord One
thousand eight hundred and ten.
DAVD BROWN, Witness.
Sworn at Dundee, this 19th day of June 1810,
before me, Chief Magistrate of the Burgh of
Dundee,
ALEX. RIDDOCK.
Inrolled the Second day of July, in the year above written.