An Improved Smoke Preventing Chimney Cowl.
Year: 1891

page_text: Date of Application, 23rd Jan., 1891
Complete Specification Left. 1st July. 1891-Accented. 15th Aug: 1891
PROVISIONAL SPECIFICATION.
An Improved Smoke Preventing Chimney Cowl.
EDWARD DOUGLAS HOYLAND Architect & Surveyor 2 Walbrook London E.C.
do hereby declare the nature of this invention to be as follows:-
A. chimney cowl to be made in tin zinc, copper, muntz metal, brass sheet iron
galvanized or otherwise and terra cotta. The cowl is conical in shape with a
spherical concavity externally and raised about 5 or 6 inches above pit or shaft and
slightly projecting beyond same and secured to shaft with four wings or if in terra
cotta cast with shaft, on the-inside of the cone is a bonnet about two thirds down
and formed to coincide with the curvature of cone externally.
I claim application of same for use on air shafts and soil pipes."
January 22nd 1891.
EDWARD DOUGLAS HOYLAND.
COMPLETE SPECIFICATION.
An Improved Smoke Preventing Chimney Cowl.
I, EDWARD DOUGLAS HOYLAND, of 2 Walbrook, in the County of London,
Architect and Surveyor, do hereby declare the nature of this invention and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
My invention has reference to a chimney cowl that can be made in tiu, zinc,
copper, muntz metal, sheet iron (galvanised or otherwise) or terra cotta to be
fixed on any existing chimney pot; or can be made with shaft complete of metal
or terra cotta. And in order that the construction of my improved cowl may be
clearly understood I append a sheet of illustrative drawings, whereof
Fig. 1 represents in vertical section one of my cowls with shaft complete
applied to a chimney top.
Fig. 2 is a sectional plan in the line C, C, of Fig. 1.
Fig. 3 is a front elevation, to a smaller scale, of a modified form of my cowl
applied to the top of a flue against the wall of a building extending to a greater
height.
Fig. 4 is a vertical section in a plane at right angles to Fig. 3.
Fig. is a plan.
As will be seen, in the example illustrated in Fig. 1, the cowl is approximately
conical in shape from A to B and from B to C is bell-mouthed, the wall of this
bell mouth being in section an arc of a circle and the general curvature C BA
being such as to deflect any wind striking the cowl externally. The part D within
the part A B is a portion of a hollow sphere adapted to coincide with the general
curvature of the part C B so as to deflect outward any smoke and gases ascending
from the shaft E. The cowl is secured to the shaft by wings, shewn at F. These
and the cowl and shaft, if of terra cotta, can be cast in one. The lower edge or
rim of the cowl may be in a plane about 5 or 6 inches above that of the top of the
shaft or chimney pot.
In the modification illustrated in Figs. 3, 4, and 5 as will be seen the curvature
of the exterior of the cowl resembles that of the previously described cowl, but
the part designed to be placed next the wall G is made flat and the interior of
the cowl is curved in a manner to form a deflector H rising from the back of the
flue I and adapted to deflect outward any ascending smoke and gases.

page_text: As will be obvious cowls according to my invention can be applied to air shafts,
soil pipes, exhaust steam pipes and the like.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
:
1. My improved chimney cowl as hereinabove described with reference to and
illustrated in Figs. 1 and 2 of the drawings hereunto annexed.
2. The modification shewn in and described with reference to Figs. 3 to 5
inclusive.
E. DOUGLAS HOYLAND.
W. Lloyd Wise,
46, Lincoln's Inn Fields, London, W.C., Agent for the Applicant.