The gold leaf. [volume] (Henderson, N.C.) 1881-1911, 1908-02-13
Wireless Fire Alarm.
Henderson 10 Have in the Near
Future a Wireless Fire Alarm
Telegraph System First Town in
the World to be so Equipped
Particulars Of the Mechanism
and Workings in Detail.

Henderson will in the near future
ENJOY n distinction peculiar to itself.
That is u wireless fire alarm fele-
graph system which is tn be installed
by the Southern Electrical Company,
the new local electrical contractors
recently established here
1t Is the purpose OF the Company,
to install one box of wireless fire
alarm i'll Henderson this to be put
III free OF charge to the town as the.
system has not yet been placed on
the market. But as it seems to be
as practical as commercial wireless
telegraphy has proven it should
cause quite il revolution in fire alarm
installations in he future rs it total
| ly eliminates the trouble caused by
crossed wires, short circuits and
grounds which seriously affect the
! proper operation OF tbe common wire
systems. 4
Mr.. C. S. Swami, secretary AMI
general manager OF the Company,
furnishes the following statement to
the GOLD LEAF:
The system operates as follows:
Each box is equipped with mechan-
ism to automatically ring the code
number of the box and is also equip
ped wit ST ora2e batteries, condenser
and spark coil, wires run from the
secondary terminals of the spark
coil to the extreme top Of the pole.
on which the box is located; the
ariels or spark balls are placed at
the top of the pole and consist of
two brass balls about one and one
half inches in diameter. These balls
are adjustable and the space between
the balls can be regulated to make
the spark any desired length When
the alarm is turned in from the box
a spark occurs between these balls
at each time the mechanism ulakes a
contact, this spark creates a mag
netic wave which travels at IA great
velocity in all directions. The dis
lance the wave is to travel is regu-
lated by the intensity and length of
the spark.
The receiving apparatus is loca-
ted at any desirable place and will re-
ceive the alarm from any number of
boxes providing only one alarm is
sent in at time The receiving APP
paratus consists OF the following:
The coherer or receiver is cOnstruc-
ted of a sealed tnbe ten inches long.
This tube is partially filled with iron
filings and has an electrode of wire
projecting from each end. These
wires are separated inside the tube
by about two inches and both wires
are connected by the iron filings:
the connection is not perfect nough,
however, to make electrical circuit
between the two wires.
When the magnetic wave created
by the spark reaches the coherer it
causes the iron filings to cohere and
forms circuit between the two wires,
it is then necessary to make the fl
ings assume their original position
again before another wave can he re-
ceived and a decoherer is used which
is constructed similar to an electric
bell Taper. This Taper is arranged
to tap against the coherer and break
up the formation Of the filings, the
whole operation requiring il very
small space Of time.
From the cOherer two wires run to
the station and are connected to a
very sensitive relay which auto
matically transmits the signals. to
the other apparatus which consist OF
tap repeater which autOmat ical|y