IMPROVEMENTS IN THE FORM AND CONSTRUCTION OF CHIMNEY TOPS OR APPLIANCES FOR SURMOUNTING CHIMNEYS
Year: 1862

page_text: LETTERS PATENT to James Durrant, of No. 3, Stangato Street, West-
minster, in the County of Middlesex, Mechanical Engineer, for the
Invention of "IMPROVEMENTS IN THE FORM AND CONSTRUCTION OF CHIMNEY
TOPS OR APPLIANCES FOR SURMOUNTING CHIMNEYS
Sealed the 6th April 1863, and dated the 11th October 1862.
PROVISIONAL SPECIFICATION left by the said James Durrant at the
Office of the Commissioners of Patents, with his Petition, on the 11th
October 1862.
I, JAMES DURRANT, of No. 3, Stangate Street, Westminster, in the County
of Middlesex, Mechanical Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN THE FORM AND CONSTRUCTION OF CHIMNEY
TOPS OR APPLIANCES FOR SURMOUNTING CHIMNEYS," to be as follows, that is
to say:
My Invention consists in forming the chimney can so that its base may be
either circular, square, or polygonal; the stalk or portion above the base is
preferably cylindrical. In those parts I do not claim anything new in form or
construction. The upper portion of the stalk is encircled by a corrugated
conical cap, the lower end of which, with the corrugations cover, project over
and encircle the upper portion of the stalk, the upper part of the conical cap
being of nearly the same diameter as the stalk, which it also encircles and
rises above. On the out side of the upper portion of the conical cap is fixed
another corrugated cap of rather smaller dimensions than the last mentioned.
The effect of the corrugations of these caps is to form channels on the outside,
which causes the exterior atmosphere to rush through the different channels
upwards; and in like manner, the air passing downwards is carried off by the

page_text: same channels. Within a small rib or bar on the top of the can is suspended
a double conical valve or float; the spindle of the valve passes through an
eye or step in the rib, and allows the valve to rise or fall when acted upon.
The diameter of the valve being less than the top of the can the smoke
reflected from the conical surface passes easily off, and similarly the down 5
draft is carried off through the corrugated channels of the cowls; the brush,
in cleaning the chimney, can also pass fairly out at the top, the valve being
raised up by it above the level of the mouth.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said James Durrant in the Great Seal. Patent Office on the 11th
April 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
DURRANT, of No. 3, Stangate Street, Westminster, in the County of Middlesex,
Mechanical Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Eleventh day of October, in the year of our Lord
One thousand eight hundred and sixty-two, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said James Durrant, Her special licence that I, the said James Dürrant, my
executors, administrators, and assigns, or such others as I, the said James
Durrant, 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 THE FORM AND
CONSTRUCTION OF CHIMNEY TOPS OR APPLIANCES FOR SURMOUNTING CHIMNEYS," upon
the condition (amongst others) that I, the said James Durrant, my executors
or administrators, by an instrument in writing under my, or their, or one of
their bands 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 James Durrant, do hereby declare the
nature of my said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement :-

page_text: My Invention consists in forming the chimney can so that its base may be
either circular, square, or polygonal; the stalk or portion above the base is,
preferably, cylindrical. In these parts I do not claim anything new in form or
construction. The upper portion of the stalk is encircled by a corrugated
conical cap, the lower end of which, with the corrugations cover, project over
and encircle the upper portion of the stalk, the upper part of the conical cap
being of nearly the same diameter as the stalk, which it also encircles and
rises above. On the outside of the upper portion of the conical cap is fixed
another corrugated cap of rather smaller dimensions than the last mentioned.
The effect of the corrugations of these caps is to form channels on the outside,
which causes the exterior atmosphere to rush through the different channels
upwards; and in like manner the air, instead of passing downwards, is carried
off by the same channels. Within a small rib or bar over the top of the can is
suspended a double conical valve or float; the spindle of the valve passes
through an eye or slip in the rib, and allows the valve to rise or fall when acted
upon. The diameter of the valve being less than the top of the can the smoke
reflected from its conical surface passes easily off, and similarly the down dralt
is carried through the corrugated channels of the cowl; the brush, in cleaning
the chimney, can also pass fairly out at the top, the valve being raised up by
it above the level of the mouth.
In order more clearly to illustrate the foregoing description, and to enable
my Invention to be more easily understood, I have to this Specification
appende the accompanying Drawings, which, taken in conjunction with the
following description, will make my Invention fully comprehensible.
DESCRIPTION OF DRAWINGS.
Figure 1 is an elevation, and Figure 2 a section, of my chimney pot or can.
Similar letters refer to the same or similar parts in both Figures.
A is the stalk or main drum, which rests on the base B; on the stalk is
placed the first corrugated conical cap C. It will be seen that the upper part
of this cone is contracted to about the same diameter as the stalk; over this
is placed the second corrugated cap D. Below the lower cone, and attached
to the shaft, are a series of oval openings or screeds E. Over the upper
corrugated cap is placed a bar F, which serves to support the valve G. The
action is as follows:-Should the wind strike against any portion of the
chimney, except at the extreme top, it must necessarily, from the form of the
two corrugated tapered caps or shields, glance off; but if it entered the upper
aperture it would strike on the double cone and pass out under the upper
shields, so that no wiud can enter the main drum. The upward passage of

page_text: smoke or air is greatly assisted by the flutes of the lower large conc; the
wind finding its way along these corrugated external channels rushes under
the upper tapered cone, drawing with it the smoke or air from within, and
which operation is greatly aided by an internal current, also formed by any
wind entering the oval screeds.
Having now described my Invention, and how the same is carried into
effect, I wish it understood that what I claim and desire secured to me by the
before in part recited Letters Patent is, the construction, use, and arrangement
of a chimney top or can with a suspended double cone, substantially as here-
within described and set forth, and more fully illustrated in the accompanying
Drawings.
In witness whereof, I, the said James Durrant, have hereunto set my
hand and seal, this Tenth day of April, One thousand eight hundred
and sixty-three.
Witness,
SAM. ARCHBUTT,
12, Copthall Court, City..
JAMES DURRANT. (L.S.)