Improvements relating to Sound Signalling at Sea and on Navigable Waters Generally.
Year: 1888

page_text: Date of Application, 19th Sept., 1888
Complete Specification Left, 19th June, 1889-Accepted, 31st Aug.. 1889
Improvements relating to Sound Signalling at Sea and on
Navigable Waters Generally.
I, JAMES STEVENSON of Grays Inn Chambers, 20 High Holborn, London, W.C. in
the County of Middlesex, Civil Engineer and Patent Agent, do hereby declare the
nature of this invention to be as follows:-
In accordance my Invention I employ compressed air which is charged into a
suitable receiver fitted on board the vessel and capable of withstanding an internal
pressure of say some 8 to 10 atmospheres. Said air receiver is fitted with an outlet
tap, to which latter is adapted any of the well known devices employed to allow of the
delivery of Sonorous Signals, such for instance as occur in the case of steam boiler
whistles, or roarers; "trumpet-mouth-shaped acoustic devices known as fog horns
and so forth.-In order to ensure that the receiver aforesaid shall be kept continually
charged with air compressed to the requisite degree to allow of the delivery of an
effective sonorous signal or a series of such signals, I employ any convenient
pumping device, and means for working same.
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In using my improved sound signalling apparatus, any desired predetermined code
of signals to suit the requirements, can be worked by the mere manipulation of the
air discharge tap, the stem of which would be furnished with a suitable operating lever
handle or equivalent.
My improved signalling apparatus will be found to be of especial value to sailing
vessels; although, in the case of steam vessels, which are provided with steam whistles
or other Sonorous Signalling devices operated by steam from a boiler,-my Invention
will in such cases also be found to be very useful as a supplementary means of
signalling to be availed of in the event of the emission passages of the steam operated
devices becoming inefficient from being choked or from any other cause or causes.
Dated this 19th day of Santamber 1888
JAMES STEVENSON.
COMPLETE SPECIFICATION.
Improvements relating to Sound Signalling at Sea and on
Navigable Waters Generally.
I JAMES STEVENSON, of Grays Inn Chambers, 20 High Holborn, London, W.C.,
Civil Engineer and Patent Agent, (a communication to me from abroad by Alexis
Lacanan of Avignon, France, Gentleman) do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
:―
The object of my invention comprises a system of signalling and apparatus therefor
by means of which it will be possible to facilitate the establishment of communications
by day, night or during fogs between two stations but principally between vessels
during fogs or mists.
Acoustic signals are more capable of effecting the desired object than luminous
ones for fogs intercept light but on the contrary carry sounds well.
It is not possible on board every vessel to produce the electric light and still loss to
produce it in a manner available for signalling.
My apparatus is shown in elevation by the accompanying figure.
It consists of a metallic receiver A capable of withstanding an internal
pressure of
say 8 to 10 atmospheres resting upon a suitable base and provided with a safety
valve B the weight P of which can be replaced by a spring of known strength.
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page_text: Upon the same base is fixed an air-pump consisting of two pumps barrels or
cylinders D, D with a beam C to which are jointed the two piston rods FF. In
order to avoid inconvenience when the pump is not at work the two levers E E which
are jointed to the beam are removable.
This pump which is worked by hand is for compressing the air in the reservoir A
and for maintaining the necessary pressure in the reservoir which pressure is
indicated by the gauge H.
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This receiver is provided with an apparatus M which may be either a "bell"
whistle like those used in steain boilers or what is known as a
"reed
whistle or a
horn etc.; in other words an acoustic instrument capable of producing shrill and
deep sounds, short or long, according as to whether the operator presses for a short
or long time upon the handle L.
The engines of steamers may be used to maintain a high pressure in the air receiver.
But it should also be possible to effect the same object by operating the compression
pump by hand being always in a position to make signals when aground or when the
fires are out, it will be possible to utilize the steam from the boilers at work to produce
acoustic signals on my system; but as it often happens that steam whistles are
momentarily rendered useless by condensed vapour it is preferable for them to be
provided with my air apparatus which can never become choked.
It is now easy to understand that vessels provided with my apparatus can not only
signal their presence, make calls, but also indicate, for instance, if they are under
sail or steam their course as indicated by the compass-their behaviour with
respect to the wind-their speed etc.-in other words to give every information and
advice of such a nature as to cause their respective positions to be recognised.
In fact it is very easy to produce at will short and long sounds by means of my
apparatus and to compose from them signals having a predetermined meaning and
related to an alphabet such as that of Morse.
Moreover a code in which the same meaning is attached to the signals in every
language might be composed taking care to keep the simplest combinations for the
indications most often used.
My system is entirely free from the following objections :-
1. It costs little to manufacture and can be fixed on board any vessel and it can be
worked by hand alone requiring no motor, steam, air or water.
2. It gives audibly the requisite indications not taking into account the direction of
the.sound.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed I declare that what I
claim is :-
The sound signalling apparatus herein described and shown, consisting of a receiver
provided with a pressure gauge and safety valve, compressed air or vapour being
forced into said receiver by two or more pumps actuated by manual or other motive
power and the escape thereof regulated and controlled through a suitable aconstic or
sound producing medium substantially as and for the purpose specified.
Dated this Nineteenth day of June 1889.