AN IMPROVED WIND GUARD OR CHIMNEY TOP
Year: 1853

page_text: PROVISIONAL SPECIFICATION left by John Dickinson Brunton
at the Office of the Commissioners of Patents, with his Petition,
on the 8th September 1858.
I, JOHN DICKINSON BRUNTON, of Truro, in the County of Cornwall,
Engineer, do hereby declare the nature of the said Invention for
"AN IMPROVED WIND GUARD OR CHIMNEY TOP" to be as follows:-
My Invention has reference to the mode of furnishing or finishing
the tops of chimneys with metal, earthenware, or cement wind guards,
caps, or tops, or in constructing the same with brick and cement in
such a manner that the natural external currents of air shall assist in
causing a draught within the chimneys so fitted. And for the better
understanding of my said Invention I shall now proceed to describe
the same, reference being had to the Drawing hereunto annexed, and
the letters marked thereon.
Fig. 1, is a front view of my improved wind guard, consisting of the
inclined portion or cap A, having vertical fixed vanes or partitions

page_text: a, a, a, fixed thereon. This conical cap is shown attached to the usual
vertical chimney top B, and both may be made of the same or of
different materials, or the cap A, may rest directly on the brickwork.
Fig. 2, is a vertical section of the same.
Fig. 8, is a front view of a similar wind guard, in which the in-
clined conical cap A, is curved all round, as at b, b, and is, as before
represented, fixed to the chimney top B.
Fig. 4, is a vertical section, showing A, curved at b, b.
I have thus described two plans for constructing the conical caps for
single chimney flues, but it is evident that on the same principle several
flues terminating in one stack may have an elongated conical top or
cap to embrace the whole. I would here observe that the vertical
projecting pieces a, form with the inclined body of the cap channels
along which the wind necessarily passes in an upward direction, which
not only discharges such currents of air directly over the chimney, but
also assist to exhaust the smoke fluc, and so cause the better ventilation
thereof. I recommend that conical caps for single chimneys be con-
structed with eight vertical vanes, cach about three inches deep, the
angle of the cone making forty degrees or thereabouts with the per-
pendicular, and that the depth of the cap be about two thirds or three
quarters of its diameter at the smaller end.
My improved wind guard may be made of metal, carthenware, and
various other materials suitable for chimney tops, and of a variety of
ornamental forms, and the lower part of the cap may be left open, or be
enclosed to exclude the wind when the mouth of the cap is attached
to a metal or earthenware tube, or the conical cap may have slots or
perforations therein to diminish the action of the wind blowing under-
neath when thus elevated. I am aware that a slight bevel has been
occasionally given to chimney tops, and that conical caps have been
placed above chimney tops, allowing under-currents to pass under such
caps, and thence over the mouths of such chimney tops, to none of
which plans do I lay any claim.
As the principle of my Invention may be variously carried out in
modifications of the figure of the cones, their number, and the materials

page_text: for their manufacture, I do not restrict myself-to dimensions, form, angle,
or material in the manufacture of such conical wind guards or caps.
And I do declare that what I claim as my Invention is, namely,-
The peculiar construction of chimney tops or wind guards in the
form of conical caps, partitioned or channelled, as described.