IMPROVEMENTS IN COWLS TO PREVENT DOWN DRAUGHTS
Year: 1885

page_text: I, WILLIAM HENRY DUPRÉ of 22 Charing Cross, St. Heliers, Jersey, one of the
Channel Islands plumber and sanitary engineer do hereby declare the nature of
my invention for " IMPROVEMENTS IN COWLS TO PREVENT DOWN DRAUGHTS," and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
This my Invention relates to an improved cowl or terminal for affixing to
chimneys to prevent the return of smoke thereto; also to aid the escape of foul air
and noxious gases from sewers &c. To carry this Invention into practice
I construct a tube or shaft of any suitable material and length or height, which
may be of any desirable cross section, on the top of which I place a cowl or terminal.
The said cowl.or terminal may be made of zinc, iron, earthenware, terra-cotta, or
other suitable material. The circumference or periphery of the terminal should be
greater than the top of the shaft or pipe to which it is affixed, and the wind pas-es
through the spaces between each concave shelf or "scallop" (hereinafter referred to)
in an upward direction and assists the smoke, gases, &c. to escape with facility from
the chimney or sewer pipe to which it may be fixed, and also prevents down
draughts. The aforesaid cowl or terminal consists of three or more vertical bars or
rods placed around the shaft or chimney, and of a suitable height to suit the force
and direction of the wind and the locality in which the shaft or chimney is erected.
Between the said vertical bars I place in a slanting direction from top to bottom of
their length, a series of shelves of a concave form, which I term "scallops" with a
space between each (scallop) for the passage of wind or air to aid the escape of
smoke and gases from the shaft or chimney. The wind is continuously passing
between the said "scallops" in an upward direction and therefore prevents return
of foul air or smoke.
In order that my Invention may be more readily understood and explained in
detail I have hereunto annexed a Sheet of Drawings on which letters of reference
are marked on corresponding parts on all the Figs. alike.
On referring to the Drawings it will be seen I have shewn a cowl or terminal the
periphery of which is divided into eight spaces or divisions by eight vertical bars,
each division having five slanting concave shelves or "scallops" (with a space
between each) in the direction of its height or length.

page_text: DESCRIPTION OF DRAWINGS.
Fig. 1. is a front elevation of my improved cowl or terminal fixed to the top of a
chimney shaft.
"
Fig. 2. is a plan view of the cowl or terminal.
Fig. 3. is a front sectional elevation through the line x-x of Fig. 2.
In these Figs. a is the shaft, or chimney, on the top of which is my improved
cowl or terminal which has eight vertical bars b forming eight spaces around its
periphery and between the said vertical bars b I fix slanting concave shelves or
scallops" (as shewn in the drawings,) with a space between each for the passage
of the wind indicated by the arrows, in an upward direction to assist the escape of
the smoke and noxious gases from the shaft or chimney, also to prevent its return,
and down draught.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
The construction of a cowl or terminal having a series of concave scallops forming
three or more complete divisions around its periphery between each of which said
divisions are fixed two or more rows of slanting concave shelves or "scallops" (with
a space between each scallop) in the direction of the length or height of the cowl or
terminal for the purposes and in the manner herein described set forth and fully
illustrated in the drawings annexed.
D
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