An Improvement in or applicable to Whistles.
Year: 1889

page_text: COMPLETE SPECIFICATION.
An Improvement in or applicable to Whistles.
I, JAMES R. ELDRIDGE, of Yarmouth, Nova Scotia, in the Dominion of Canada,
Engineer, 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:
This invention relates to an improvement in whistles of the class in which steam
or other fluid under pressure is employed for producing the sound; its object being
to deflect the sound-waves horizontally and to project them over a wide area.
The accompanying drawing represents in vertical section a steam-whistle em-
bodying the present invention, which may nevertheless be applied to whistles of other
form.
In the drawing, a is a chamber having a closed top in which are formed two
straight parallel slits a' through which the steam or other fluid escapes. is a bell
provided with two lateral openings b¹ which prosent edges opposite to and parallel
with the slits a', the streams of fluid as they issue from the orifices a striking against
the said edges. The sound-deflector e consists of a body, which may be either
hollow, as shewn, or solid; its under surface being, in either case, curved. A central
stem c projects downwards from the under side of the deflector; the centre c of the
under surface being curved, upwards from the base of the stein. The part of
the under surface, which is next the periphery of the deflector, should be in a
horizontal plane, as represented. As seen from above, the deflector should be
circular; its upper surface es being by preference convex in order to facilitate the
dislodgment of water or snow.
For connecting the deflector with the whistle, a rod d may be employed. One end
of the rod is screwed or otherwise secured in the centre of the upper surface of the
chamber a, whence the rod passes vertically upwards through, and projects beyond,
the hell. The projecting extremity of the rod is screw-threaded; the deflector being
by preference tapped to correspond, and d serving as a lock-nut. The deflector may,
however, be attached to the whistle in any convenient manner, and its general
contour may be varied considerably without departing from the principle of the
invention. The upper surface, for instance, need not project beyond the plane of
the periphery.
Having now particularly described and ascertained the nature of this invention
and in what manner the same is to be performed, and observing that the present
application for Letters Patent is made within the term of priority of seven months
prescribed by Article 4 of the International Convention for the protection of

page_text: Industrial Property dated the 20th March, 1883, a United States Patent for the
said invention having been applied for on 25th February, 1889, No. 301,030,
I claim:-
For use with a whistle, a sound-deflector arranged axially therewith and formed
with a concave surface against which the stream of fluid issuing from the whistle
impinges and whereby the sound is projected in a radial direction.
Dated the 24th day of September 1889.
G. G. M. HARDINGHAM,
191, Fleet Street, London, E.C., Agent for the Applicant.