The Goldfield news and weekly tribune. [volume] (Goldfield, Nev.) 1911-1947, 1914-06-27

sible, by a special signal, TO all all
the stations and speak to all stimuli
taneously. The current required is
furnished by an ordinary battery; in
fact, in outward appearance the tele-
phones are exactly similar to an or
binary mining telephone.
The portable instrument, which can
be carried about and used in any
part of the mine to which rails ex-
tend, is contained in a strong metal
case, the total weight being about
20 pounds. The telephone can eth
er ring up the other stations or be
rung up by them. A smaller or pock-
ct instrument is also made, which
can ring up other stations, but can
not be called by them. With this
instrument messages can be sent to
or received from any OF the fixed
telephones, the only difference be-
tween it and the heavier portable
type being that the other telephones
cannot call it by ringing it's bell.
Thus each official provided with an
instrument can give notice of any
dSCluChL III dom " dSSlStduCC IIOll
any point in the mine.
A telephone can be fixed at any
convenient position on the surface,
and connected to the headframe, if
of iron. OF to the hosting rope or
pipes which go down the shaft. This
telephone a speak to any Of the
telephones underground If necessary,
but it is usually found more convent
ent to arrange for it to speak to the
station at the pit bottom only, and
for this station inturn to speak to
the underground telephones. In
metalliferous mines, where a num-
Der of different levels run from the
shaft, communication can be estab-
lished from n level to another as
required, the presence of the ore
bodies not affecting the speaking in
any way.
A further most important applica-
ton of the system is that Of speak
ing from the moving cage to the
hoist house, and for the latter posi-
ton the inventor has designed an
ingenious method of operation. The
telephone is mounted on a standard
fixed close to the hosting engineers
a On receiving a call, he has
only to put his ear to the receiver,
and the slight pressure is sufficient
to switch in the telephone and en-
able him to communicate with the
cage, without removing his hands
from the levers. Various methods of
connection are possible for the tele-
phone in the cage, n of the most
satisfactory being connection into a
loop formed by the hosting ropes.
and by the balance rope Cor, If this
is lot used. by a wire suspended be-
low the cage in the same way). 1t is
then possible to speak from either
cage to the surface or to the pit bot
tom, without any alteration in the
ordinary hosting arrangements. The
surface telephone is preferably con-
nected in circuit with a loop of wire
fixed to the headgear, Dr. in the shaft
in any convenient place.
Several methods of telephoning
from the cage to the shaft have been
previously proposed, such as the con-
struction of a hosting rope contain
ing an insulated wire. or the insula-
ton of the attachment of the rope to
the cage and also the overhead
sheave, etc., or the use of sliding
contacts to a wire suspended in the
shaft. There are definite defects in
all these methods, but they need not
be discussed, as the best argument
against them is that none Of them
has come into use.