IMPROVEMENTS IN APPARATUS FOR THE TRANSMISSION AND INDICATION OF SIGNALS
Year: 1871

page_text: PROVISIONAL SPECIFICATION left by Marshall Arthur Wier at the
Office of the Commissioners of Patents, with his Petition, on the
30th September 1871.
I, MARSHALL ARTHUR WIER, of No. 9, Gt. Winchester Street, in
the City of London, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN APPARATUS FOR THE TRANSMISSION AND INDICATION OF
SIGNALS," to be as follows:-
The Invention relates especially to pneumatic apparatus for sending
and receiving audible or visible signals, but certain parts thereof are also
applicable to apparatus operated mechanically.
My improvements, so far as they relate to the sending instrument
(herein-after called the communicator), consist,—
Firstly. In adapting to the cylinder and piston sometimes employed
for compressing the air, a tap, or valve, or surfaces acting as such, by
which the communication between the compressing cylinder and the
tube leading to the distant receiving instrument (herein-after called the
indicator) shall be closed when the piston is pressed down; by this
means the air forced into the pipe is retained therein, and the air-tight

page_text: fitting of the piston or other working parts becomes less important
than heretofore. In order to obviate or modify the inconvenience of
leakage around the piston, I also sometimes employ two pistons with an
air space between them; on one of the said pistons being quickly pressed
towards the other the air contained between them is compressed,
forming a cushion which resists to some extent the escape of air from
the body of the cylinder, when the two pistons are immediately after-
wards together pressed towards the bottom thereof.
Secondly. Instead of employing a separate valve to govern the inlet
and outlet of air to and from each pipe leading from a communicator
to an indicator, as set forth in the Specification of a Patent granted to
Arthur McNutt Wier and myself, dated September 24th A.D. 1868,
No. 2929, I employ a single rotating, conical, or cylindrical plug or flat
disc, or a reciprocating slide valve, provided with an aperture by which
any one of the several pipes leading to the indicator (which open in the
face against which the said plug or slide valve. works) may be placed in
communication with the air compressing apparatus, the other pipes
remaining shut off therefrom, but opened to the atmosphere by means
of suitable grooves or slots formed in the said plug or valve. The plug
or valve and compressing instrument may be operated by the swivelling
handle and central spindle described in the Specification No. 2929, before
referred to.
**When it is required to adapt this apparatus to the purpose of sending
signals indicative of numbers, as, for example, in the case of directing the
fire of ship's guns, in which it may be necessary to indicate the degrees
to which the guns are to be trained by 2 or 3 figures at once, I avoid
the necessity for employing a separate set of communicating apparatus
for each denomination of figures by combining together two or more of
the above-mentioned plugs or valves, so as to act in unison with each
other, one plug or valve governing the pipes leading to "units" figures
in the indicator, another those leading to "tens" figures, a third those
leading to "hundreds" figures, and so on. The apertures and grooves
or slots in the plugs or valves for admitting and letting out the air, are
so arranged in relation to the pipes, and the motion of the plugs or
valves in relation to each other so regulated by wheelwork or otherwise,
that each complete revolution of the “units." plug or valve brings the
outlet aperture of the "tens" plug or valve opposite a fresh. "tens
pipe, and so on to any required extent.
"

page_text: The pointer over the dial face of the communicator is connected by
uitable mechanism with the plugs or valves in such manner that when,
t is moved to any signal marked on the dial face, the plugs or valves
hall be moved so as to open communication between the air-
compressing instrument and the appropriate pipes leading to the
corresponding air vessels, or other transmitting media in the indicator;
and by similar combinations of two or more suitable plugs or valves
various other combinations of signals besides numbers may be obtained.
My improvements, so far as they relate to the receiving instrument
or indicator, consist,―
"
Firstly. In certain means whereby the movement of the pointer over
a dial face, or that of a revolving drum behind an opening, or of other
indicating medium to certain definitè positions in exact accordance with
the signals transmitted by the communicator, is effected with greater
certainty and accuracy than by the methods heretofore practised. I
prefer to use for each signal to be indicated, a separate small flexible
air chamber similar to those described in the Specification of a Patent
granted to Arthur McNutt Wier and to myself, bearing date the 29th
August, A.D. 1867, No. 2468, a small cylinder, and piston or plunger,
or a cup floating in mercury or other fluid, but any other suitable
transmitting medium may be employed. In order to give the exact
amount of motion required when the arc over which the pointer is to
be moved is large, I employ an axis on which are placed tail pieces
corresponding to and acted upon by the air chambers or other media
employed to transmit motion. The tail pieces are so arranged in
relation to the axis and to certain fixed stops, that each one on being
acted upon by its corresponding air chamber is capable of imparting a
certain amount of angular motion to the said axis; the action of each
air chamber and tail piece on the axis being independant of the others.
The axis carrying the tail pieces is connected to that of the pointer in
such a manner that the motion communicated to it by the tail pieces
is conveyed in any desired proportion to the axis of the pointer. When
the arc over which the pointer is to be moved is small, the tail pieces
may be placed direct on the axis of the pointer and made to move it to
5 definite positions without employing the intermediate axis.

page_text: periodical, and in which the effects are produced by means of coloured
or more or less opaque fluids or liquids interposed between the light
and the observer; I employ a series of glasses between which spaces
are left to contain the fluids which give colour to the light; the spaces
are in communication by tubes with separate reservoirs containing the
coloured fluids, by forcing air into or withdrawing it from the reservoirs
or into or from the spaces between the glasses, the fluid may be
interposed between the observer and the light, or withdrawn as may be
desired. This may be effected by means of a communicating apparatus
such as herein-before referred to, or any other suitable apparatus for
compressing or exhausting air.
Instead of displacing the coloured fluids by means of air, I sometimes
effect that object by immersing a float or other body in the reservoir by
mechanical means, so as to raiso the level of the fluid therein and
consequently in the space between the glasses.
Another part of my improvements consists in a simple means of
conveying to the operator an indication that his signal is received. I
place a tap in the attention bell pipe at the receiving end; this being
opened when the attention bell rings, allows a portion of the air that
has rung the attention bell to return to the operator by a second pipe 2
and ring the reply bell.
To indicate to the operator that his signal has not only been received
but is being or has been carried out, as in the case of showing on the
bridge of a steamer whether the engines are set to go ahead or astern,
I place a three-way tap in connection with the reversing gear of the 2
engine in such a manner that if the latter is moved into the position
for going "ahead" the three-way tap is turned so as to open
communication between the pipe from the communicator on the bridge
and the pipe from engine room to "ahead" in the indicator on the
bridge; if the operator now acts upon the compressing instrument the 3
indicator before him will point to "ahead," if the engines are reversed
"astern" will be indicated, and in some cases if the engines are not
moving "stop" is indicated.
A similar arrangement of apparatus is also applicable to signalling on
railways, as in the "block" system now worked by electricity, and for 3
this purpose I employ a tap or valve operated automatically by the
indicator apparatus (which may consist of miniature semaphores) to

page_text: open communication with a pipe by which the air (which I prefer to
supply from a reservoir of compressed air) that gave the signal returns
to the "tell-tale" at the communicator, and indicates that the signal
has been properly given at the distant end; if the signal has not been
properly given the valve is not acted upon, and the "tell-tale" remains
stationary.