IMPROVEMENTS IN ELECTRIC TELEGRAPH AP- PARATUS
Year: 1876

page_text: PROVISIONAL SPECIFICATION left by Robert Stevenson Symington at
the Office of the Commissioners of Patents on the 13th May 1876.
ROBERT STEVENSON SYMINGTON, of Glasgow, in the County of Lanark, North
Britain, Telegraph Engineer. "IMPROVEMENTS IN ELECTRIC TELEGRAPH AP-
PARATUS."
This Invention relates in part to improved apparatus to be used at a central
telegraphic station or office to which a number of wires are led from different works,
business establishments, or stations, such apparatus being designed to facilitate the
work or manipulation and to allow of any two wires being coupled and used for
private messages between the respective firms to which they belong.
Another part of the Invention relates to the apparatus of fire-alarm telegraphs,
and is designed to admit of any fire-alarm communicator being put in connection
with a portable message sending and receiving instrument, and generally to improve
the apparatus and render it less liable to derangement.
In carrying out the first part of the Invention the several wires of a number are
led down to a bar of non-conducting material, and their ends are set to spring or
are pressed by springs into shallow grooves, in the bottoms of which grooves are
fixed wires connected with electric bells. The end of each line wire is curved up
so that a metallic connecting slip can be inserted between it and the bar, and this
slip whilst itself making contact with the line wire lifts that wire out of the groove
and out of contact from the bell wire. Some connecting slips are attached to
insulated wires in connection with message sending and receiving instruments in
the office, whilst other connecting slips are attached to pairs of wires, each pair
serving to couple together any two line wires for the through transmission of a
private message. Each pair of coupling wires is arranged in connection with a
small indicating instrument showing a needle or pointer, which is in a state of
vibration whilst a message is being transmitted, and by it the attendant at the
central office knows when a private message is discontinued so that he can uncouple
the line wires.
The improved fire-alarm apparatus is comprised principally in casings to be fixed
in easily accessible positions scattered over a town, and from which wires are led to
a central fire engine station. In each casing thero is a key for transmitting an
alarm signal, and this key is covered with glass, which protects it, and has to be
broken to get access to the key. There is also in cach casing an electric bell, which
is sounded as an acknowledgement of the receipt of the signal. In the key or in
ID 071

page_text: connection with it there is a hole for receiving the connector of a portable message
sending and receiving instrument, this connector being in the form of a handled
spindle attached to the instrument by two insulated wires, one of which is con-
nected to a central pin insulated from the rest of the handle. When this connector
is thrust into the hole provided for it in the alarm casing it acts on internal
mechanism so as to put the line wire in communication with the instrument and
so that messages may be transmitted. Thus when the superintendent of the fire
brigade has reached the scene of a fire he can use the alarm wire to telegraph orders
to the central station, such as for additional engines, or to stop their being sent.
Each casing is by preference in the form of a circular box, having an elongated part
extending upwards from it, and which may have any suitable or ornamental form
externally. This upper part of the casing is to receive a battery for supplying the
requisite current, and this battery is by preference arranged in a moveable frame
or holder, which can be taken entire out of the casing after disconnecting a couplo
of wires. The battery may be of any suitable known kind, and it may be arranged
to be always in action, that is with the elements immersed in the exciting liquid, it is,
however, preferred to have the elements attached to a vertical rod, which ordinarily
holds them up out of the exciting liquid, but which is let down by a trigger action
whenever the key is pressed for the purpose of transmitting an aların signal.