PREVENTING SMOKE, DUST, AND THE DANGER OF FIRE, AND FOR ENCREASING AND REGULATING HEAT FROM STOVES AND CHIMNEY FIRE-PLACES, FOR HEATING ROOMS, HALLS, PASSAGES, AND STAIRCASES IN PUBLIC BUILDINGS AND DWELLING-HOUSES, AND ALL OTHER APART- MENTS WHERE REGULATED HEAT AND CLEANLINESS ARE DESIRABLE, WITHOUT OBSTRUCT- ING THE VIEW OF THE BURNING FUEL
Year: 1810

page_text: CLERK'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, WILLIAM
CLERK, Esquire, Advocate, sends greeting.
WHEREAS the King's most Excellent Majesty, by Letters Patent Patent
under the Great Seal of the United Kingdom of Great Britain and Ireland,
bearing date the Second day of May, in the fifteenth year of His reign, gave and
granted unto the said William Clerk, his executors, administrators, and assigns,
His Majesty's special licence, full power, sole privilege and authority, that he,
the said William Clerk, his executors, administrators, and assigns, and every of
them, by himself and themselves, or by his or their deputy or deputies, servants
or agents, as he, the said William Clerk, his 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 of years therein expressed, should and
lawfully might make, use, exercise, and vend, his Invention for "PREVENTING
SMOKE, DUST, AND THE DANGER OF FIRE, AND FOR ENCREASING AND REGULATING HEAT
FROM STOVES AND CHIMNEY FIRE-PLACES, FOR HEATING ROOMS, HALLS, PASSAGES,
AND STAIRCASES IN PUBLIC BUILDINGS AND DWELLING-HOUSES, AND ALL OTHER APART-
MENTS WHERE REGULATED HEAT AND CLEANLINESS ARE DESIRABLE, WITHOUT OBSTRUCT-
ING THE VIEW OF THE BURNING FUEL," within that part of the United Kingdom

page_text: of Great Britain and Ireland called England, the Dominion of Wales, and
Town of Berwick upon Tweed, in such manner as to him, the said William
Clerk, his executors, administrators, and assigns, or any of them, should in.
his or their discretion seem meet; in which said Letters Patent is con-
tained a proviso that if the said William Clerk should not particularly
describe and ascertain the nature of his said Invention, and in what manner
the same is to be performed, by an instrument in writing under his hand and
seal, and cause the same to be enrolled in His Majesty's High Court of Chan-
cery within six callender months next and immediately after the date of the said
Letters Patent, that then the said Letters Patent, and all liberties and advantages
whatsoever thereby granted, should utterly cease, determine, and become void,
anything therein contained to the contrary thereof notwithstanding.
NOW KNOW YE, that the said William Clerk doth, by this instrument
in writing under his hand and seal, duly executed, describe and ascertain the
nature of his said Invention, and the methods by which the same may be per-
formed, that is to say:-
The said Invention is susceptible of various forms and modifications, accord-
ing to the particular nature and situation of the apartments, or the particular
situation and form of the place in which the stove or grate is to be placed,
as, for instance, first when the grate or stove is to be placed near the wall
of an apartment or within an ordinary fire-place; the grate for containing
the fuel is to be inclosed, excepting on the side towards the apartment, with
upright plates of iron or other suitable material, and covered on the top with
another plate of the same material, having a pipe or aperture on or near the
top of proper diameter for conveying the smoke of the fire into the chimney,
and excepting hy this pipe or aperture, there ought to be no ordinary access of
air into the chimney. On the front, which thus remains open towards the
apartment, and accurately fitted to the sides and top above described, is to be
placed a frame of metal or other proper material, having various bars and sub-
divisions, with proper grooves in each, into which are nicely fitted pieces of
glass of proper form and size. In its simplest form this frame or screen is
constructed of upright bars, crossed or checquered with other bars in a hori-
zontal or other form, into the openings of which the glass is fitted, or having
the pieces of glass so accurately cut, and brought so exactly into contact with
one another at the upper and under edges, as to supersede the necessity of any
cross or horizontal bars. For the purposes of ornament, and without impeding
its utility, the frame or screen may be constructed in imitation of a Gothic
shrine, or in various fanciful and elegant forms, having the pieces of glass

page_text: either plain or cut, stained or painted. The frame of glass ought not to be
placed nearer the grate than nine or ten inches, and the pieces of glass ought
not in that case, nor in general, to exceed three inches square, otherwise the
glass is apt to crack or break, but in these respects considerable varieties are
admissible, provided the size of the pieces of glass bears a due proportion to
the distance of the frame from the bars of the grate, and to the greater or less
intensity of the heat to which the glass is exposed. The frame is so constructed
as cither to be occasionally removed altogether or to open totally or in part, by
means either of binges or sliding grooves, or otherwise, so as to give access
when necessary to the fire-place. In order to supply the fire within the stove
with air two different expedients are employed, either separately or alternately.
In the first place, by means of a tube with a valve or stop-cock, communicating
between the interior of the stove and the external air, or the air of some
contiguous apartment, the fire is supplied independently altogether of the air
of that apartment which it is intended to warm. Or, in the second place,
in the lower part of the screen nearest to the hearth, or in the sides of the
stove, an aperture is made, having a proper regulator or damper, which may
be opened or shut at pleasure. In this last manner the fire may be entirely
supplied with air from the apartment where it is placed, or if the valve of the
tube in the first method be partially or totally opened, the supply may be
furnished partly from the apartment and partly from the external air, or the
alternate accumulation of heated air and renewal of cool and fresher air in
the apartment; may be managed and regulated at pleasure. The effects and
advantages of this Invention, when thus applied, are various. In the first
place, it has the effect of heating the apartments more easily and equably than
by open fire-places, by admitting of an accumulation of air heated by immediate
contact with every part of the stove, as well as by radiation from the body of
the stove, and through the diaphanous screen which is placed in front of it,
while at the same time this accumulation may be occasionally checked or
diminished, and a gentle or regulated ventilation may be had by means of the
aperture with its damper in the lower part of the stove, or even by opening the
screen by means of its hinges or sliding grooves. Next, a fire-place_thus
constructed effectually prevents all the inconveniences so much felt and com-
plained of occasioned by smoke and dust, as well as the hazards of fire arising
from sparks or from the falling of pieces of the burning fuel, while at the same
time, and in the third place, the view of the fire is not obstructed, and the
chearfulness and comfort of an open fire-place are retained. It is the combi-
nation of this last circumstance with the former which gives to this Invention

page_text: its peculiar character, and its superiority over any species of stove or fire-place
now in use. Secondly, when the stove or fire-place is to. be situated in the
center of an apartment, or at a distance from the walls, the grate may be
circular or of any other convenient or elegant form, and is to be surrounded and
enclosed with a frame work of materials and construction similar to those of
the screen above described. Over this surrounding screen, and in contact with
it, is placed a top or canopy of metal, or other proper material, from which
proceeds the flue or tube that conveys the smoke. The fire is to be supplied
with air by the means already specified under the former head, and by similar
arrangement the heat and ventilation of the apartment may be exactly regu-
lated. Thirdly, in combination with ordinary grates or in open fire-places, or
with register stoves, this Invention is usefully and conveniently applied by
placing a diaphanous screen of the construction already described, accurately
fitted to the openings in front of such stoves or fire-places, and by supplying
the fire with air either from without or from within the apartment by means of
the apparatus already specified under the former heads. When employed in this
less perfect manner the process of heating the apartment requires a greater
consumption of fuel, but in other respects the advantages are similar in kind,
if not in the same degree.
In witness whereof, I, the said William Clerk, have hereunto set my
hand and seal, this Twenty-second day of October, in the
our Lord One thousand eight hundred and ten.
of
year o
WILLIAM CLERK. (L.S.)
Signed, sealed, and delivered (being 'first
duly stamped) in the presence of
ROBT. FERGUSON,
of Nottingham Place, Marylebone, London.
Robert Ferguson, of Nottingham Place, Marylebone, London, Esquire,
maketh oath and saith, that he did see William Clerk, mentioned in the deed
poll hereunto annexed, sign, seal, and as his act and deed, in due form of law,
deliver the said deed poll, in the presence of Lucas Spilsbury, mentioned as
a witness in the said deed poll, and this deponent, and that the names, William
Clerk, appearing to be set and subscribed at the foot of the said deed poll as

page_text: the party executing the same, and Rob Ferguson and Lucas Spilsbury, set
and subscribed to the said deed poll as witnesses attesting the due execution
of the same, are of the respective handwriting of the said William Clerk, Lucas
Spilsbury, and this deponent, Rob Ferguson.
Sworn at Bawtry, in the County of York, by this deponent, on Monday the
Twenty-second day of October, One thousand eight hundred and ten, before
me.