IMPROVEMENTS IN CHIMNEY TOPS FOR THE PURPOSE OF PREVENTING OR CURING THE DOWN DRAUGHT OF SMOKE
Year: 1866

page_text: LETTERS PATENT to John Denley, of Cheltenham, in the County of
Gloucester, for the Invention of "IMPROVEMENTS IN CHIMNEY TOPS FOR
THE PURPOSE OF PREVENTING OR CURING THE DOWN DRAUGHT OF SMOKE."
Sealed the 7th May 1867, and dated the 10th November 1866.
PROVISIONAL SPECIFICATION left by the said John Denley at the Office
of the Commissioners of Patents, with his Petition, on the 10th November
1866.
I, JOHN DENLEY, of Cheltenham, in the County of Gloucester, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN CHIMNEY TOPS
FOR THE PURPOSE OF PREVENTING OR CURING THE DOWN DRAUGHT OF SMOKE,” to
be as follows:-
This Invention relates to certain improvements in the construction of
chimney tops or pots whereby the down draught of smoke is prevented.
I propose to place on the top of the ordinary plain chimney pot an open.
inverted conical cap or hoop of metal or potteryware surmounted by another
of the same shape, and joined thereto from its edge by vertical wires or slips
of metal; on the top of the upper one I place. a circular horizontal flat plate
or disc raised by three or more vertical wires or standards from the edge of
the hoop, so that supposing the wind. were to blow up the lower hoop or over
it it would force the smoke up to the plate and thence out from the chimney.

page_text: I increase the number of these hoops where great draft is required. In
some cases I surmount the uppermost hoop with a reversed conical hoop with
the lines of its apex downwards; the object being to cause the current of air
to diverge from the lower hoop and from the top of the chimney; the plate
or disc would in this case be just above the level of the reversed hoop. By
these arrangements it is obvious that the current of air would be caused to aid
the up draught, and thus carry off the smoke from the chimney, and obviate
the tendency to a down draught, which has hitherto been difficult to
accomplish. The Invention is applicable to two or more tops joined side
by side.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Denley in the Great Seal-Patent Office on the 10th May
1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DENLEY, of Cheltenham, in the County of Gloucester, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of November, in the year of our Lord
One thousand eight hundred and sixty-six, in the thirtieth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Denley, Her special licence that I, the said John Denley, my
executors, administrators, and assigns, or such others as I, the said John
Denley, 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
CHIMNEY TOPS FOR THE PURPOSE OF PREVENTING OR CURING THE DOWN DRAUGHT OF
SMOKE," upon the condition (amongst others) that I, the said John Denley,
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 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 John Denley, do hereby declare the
nature of my said Invention," and in what manner the same is to be per-

page_text: formed, to be particularly described and ascertained in and by the following
statement:
This Invention relates to certain improvements in the construction of.
chimney, tops or pots whereby the down draught of smoke is prevented.
I
I propose to place on the top of the ordinary plain chimney pot an open
inverted conical cap or hoop of metal or potteryware surmounted by another
of the same shape, and joined thereto from its edge by vertical wires or slips
of metal; on the top of the upper one I place a circular horizontal flat plate
or disc raised by three or more vertical wires or standards from the edge of
the hoop, so that supposing the wind were to blow up the lower hoop or over
it, it would force the smoke up to the plate and thence out from the chimney;
I increase the number of these hoops where great draft is required. In
some cases I surmount the uppermost hoop with a reversed conical hoop with
the lines of its apex downwards, the object being to cause the current of air
to diverge from the lower hoop and from the top of the chimney; the plate
or disc would in this case be just above the level of the reversed hoop. By
these arrangements it is obvious that the current of air would be caused to
aid the up draught, and thus carry off the smoke from the chimney and
obviate the tendency to a down draught, which has hitherto been difficult to
accomplish. The Invention is applicable to two or more tops side by side.
In order that my said Invention may be completely understood I annex a
Sheet of Drawings, in which Fig. 1 represents an elevation of a chimney pot
constructed on my principle; Fig. 2, a section of the same; and Fig. 3, an
elevation of a double chimney pot. Similar letters denote corresponding parts
in each Figure.
a is the circular flat plate or disc held by supports on the top of the chimney
pot; this plate is fixed accurately in a horizontal position; b is the upper
circular hoop of sheet tin, zinc, or other metal whose sides slope conically,
and c is the lower hoop of similar form and material fitted as a flange to the
chimney pot d, the upper hoop being supported by standards on the lower one.
Fig. 4 represents an elevation of the chimney pot having a reversed conical
hoop e, the edges of which are flush with the plate f, shewn in dotted lines,
and supported by stays.
Having now described the nature of my said Invention, and the manner in
which the same is to be performed, I would remark in conclusion that I do
not limit myself to the precise details and configuration of parts I have
expressed and shewn, as the same may be slightly varied or modified without
departing from the principles of the Invention; but what I claim and desire
to be secured to me by the herein in part recited Letters Patent is, the appli-

page_text: cation to chimney pots of circular hoops of a conical section in conjunction
with or surmounted by a circular horizontal disc or plate supported by.
standards or stays for the purpose of preventing or curing the down draught
of smoke in chimnies, substantially as herein specified and shewn.
In witness whereof, I, the said John Denley, have hereunto set my
hand and seal, this Seventh day of May, in the year of our Lord:
One thousand eight hundred and sixty-seven.
Witness,
HENRY ALFRED JAMES,
Training College, Cheltenham.
JOHN DENLEY. (L.s.)