IMPROVEMENTS IN CHIMNEY TOPS OR TERMINALS AND VENTILATORS FOR DWELLING HOUSES And OTHER BUILDINGS
Year: 1877

page_text: PROVISIONAL SPECIFICATION left by Henry Prentis at the Office of the
Commissioners of Patents on the 15th January 1877.
HENRY PRENTIS, of Milkwood Road, in the County of Surrey. "IMPROVEMENTS
IN CHIMNEY TOPS OR TERMINALS AND VENTILATORS FOR DWELLING HOUSES And
OTHER BUILDINGS."
My Invention relates to improvements in chimney tops or terminals, and consists
in a novel construction of the same, whereby I provide the means for ensuring a
free upward draught in a chimney, while effectually preventing any downward
draught through the same, and leaving free space for the passage of a sweep's
brush or cleansing implement. This novel construction is applicable to chimney
pots, tops, or terminals of metal, terra cotta, or other material, and is also
applicable to ventilators for rooms or apartments of dwelling houses and other
buildings.
The said Invention consists in forming the chimney top or terminal with a series
of transverse or horizontal apertures or openings on two opposite sides, below or from
the under side of which openings project vanes or diaphragms, which have an
upward inclination or slope inward toward the centre of the chimney top or
terminal.
The said openings on the opposite sides of the chimney top are not arranged
opposite each other, but those on one side are between those on the other side.
The said diaphragms extend entirely across the chimney top, but those of one
side do not overlap or meet those of the other side, so that between the two series of
diaphragms there is through the chimney top or terminal a clear vertical central
space which affords a clear passage for a brush or other implement used for cleaning
the chimney.
The apertures may be covered externally by inclined or sloping projections or
guards. Therefore each of the said two opposite sides of the top or terminal
consists of a series of inclined or sloping passages or a zig-zig passage extending
from the centre downwardly and outwardly to the opposite sides of the chimney top
or terminal.
The result of this construction is that the wind blowing against the sides of the
chimney, and entering the said apertures, will be guided by the said vanes or
diaphragms in an upward direction, and will tend to improve the draught of the
chimney, while any downward current or draught will be diverted to one side or

page_text: the other through the said apertures, and will therefore not pass down the chimney
or obstruct the upward draught of the same. Therefore with my Invention applied
to it, a chimney of imperfect formation, and in the most unfavorable position, if
kept in an ordinary condition of cleanliness, may be effectually cured of smoking at
a moderate cost, and without the unsightly appearance, and other disadvantages
attendant upon the appliances heretofore employed for this purpose.
In adapting this Invention to ventilators for dwelling houses and other buildings,
the construction is the same as above described, but as they will not require
sweeping or cleansing, it will not be necessary to leave a clear vertical passage
through them between the sloping or inclined diaphragms. The said ventilators
may be attached to the roof or any other convenient part of the house or building.