Improvements in or relating to Steam or Pneumatic Whistles, Horns, or the like.
Year: 1897

page_text: Date of Application, 1st Dec., 1897
Complete Specification Left, 29th Mar., 1898-Accepted, 2nd July, 1898
PROVIDIONAL
DIECIFICATION.
Improvements in or relating to Steam or Pneumatic Whistles,
Horns, or the like.
I, JOHN MILLER, of the Firm of Smith Bros. & Company, Bobbers Mill
Road, Hyson Green, in the City of Nottingham, Engineer, do hereby declare the
nature of this invention to be as follows:
This invention relates to improvements in steam or pneumatic whistles, horns,
or the like, employed on steam ships, locomotives, and in numerous other cases
for giving audible signals, and it has for its object the manufacture of a duplex
whistle or horn that will produce a tremulous note or a trill, which it is well
known is more penetrating and is thus heard more distinctly at a distance, than
an uninterrupted note or notes.
Heretofore a tremulous note or trill has been produced_by_such-instruments,
by introducing a mechanical device into the current of steam or air, such for
example as a ball, or revolving disc or the like, or a reciprocating plunger.
These devices however when operated by the current of steam or air passing
through the whistle, throttle the said current, and thus reduce the volume of
sound produced, and defeat the main object for which they are designed.
In carrying out my invention I make a whistle or horn duplex, that is form it
of one casing and subdivide it into two distinct parts, each of which may be
tuned to a different note, or make it with two distinct casings.
One part of the whistle or horn is formed so as to preferably produce a note
which is in tune with any note in the diatonic scale, whilst the other part is
formed so as to produce a note which is approximately one quarter of a full
note higher or lower than the first part.
The desired result is obtained by making the two parts of the whistle with an
interval of approximately one quarter of a full note between them.
In a whistle or horn constructed in the manner described each distinct part of
it will give a smooth note, but when both are blown together the sound which
reaches the ear of a listener is a tremulous note or trill, similar to that given by
what is known as an ordinary pea-whistle.
Dated this 1st day of December 1897.
Improvements in or relating to Steam or Pneumatic Whistles,
Horns, or the like.
I, JOHN MILLER, of the Firm of Smith Bros. & Co., Bobbers Mill Road, Hyson
Green, in the City of Nottingham, Engineer, do hereby declare the nature of this

page_text: 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 improvements in steam or pneumatic whistles, horns,
or the like employed on steam ships, locomotives, and in numerous other cases
for giving audible signals or warnings and its object is to provide a whistle or
horn that will produce a tremulous note or a trill, which it is well known is
more penetrating and is thus heard more distinctly at a distance than an
uninterrupted note or notes.
Heretofore a tremulous note or trill has been obtained in such instruments by
mechanical means, that is, by the introduction of a mechanical device into the
current of steam or air, such for example as a ball, revolving disc, reciprocating
plunger, or like device.
These devices however when operated by' the current of steam or air passing
through the whistle, throttle the said current and reduce the volume of sound
produced, and thus defeat the main object for which they were designed.
In carrying out my invention I produce a tremulous note or trill by adjusting
the pitch of two contiguous or adjacent whistles or horns relatively to each other.
For this purpose I employ what is known as a duplex whistle, which may be
formed by one casing which is subdivided by a central partition into two dis-
tinct parts, each of which may be tuned to a different pitch in a well known
manner, or make it with two distinct casings which may be connected to the
same base or supply pipe.
One part of the duplex whistle or horn is so adjusted as to preferably produce
a note which is in tune with or the same pitch as any note in the diatonic scale,
whilst the other part is so adjusted as to produce a note which is pitched approxi-
mately one quarter of a tone or half a semi-tone higher or lower than the pitch
of the other part.
For example if one is tuned to C natural the other part is adjusted to give a
note which is approximately half a semi-tone higher, that is half way between C
natural and C sharp, or half a semi-tone lower that is half way between C natural
and B natural.
In a duplex whistle or horn in which the pitches of the two parts are adjusted
in the manner described cach distinct part of it will give a smooth note, but
when both are blown together the sound which reaches the ear of a listener is
a tremulous note or trill, similar to that given by a whistle which has a solid
moveable object such as a ball in the casing.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what
I claim is:
1. A. duplex steam whistle one part of which is adjusted to give a note which
is pitched one quarter of a full tone or half a semi-tone higher or lower than the
pitch of the other part substantially as and for the purpose described.
2. A duplex steam whistle one part of which is adjusted to give a note which
is in tune with a tone or semi-tone of the diatonic scale and the other a note
which is pitched one quarter of a full tone or half a semi-tone higher or lower
than the pitch of the other part substantially as and for the purpose described.
Dated this 10th day of March 1898.
JOHN MILLER.
Boult & Wade,
Agents for the Applicant.