The watchman and southron. [volume] (Sumter, S.C.) 1881-1930, 1918-12-18
Multiplex Telephone and Tele-
graph is Now Per-
fected.
MEANS A BIG ADVANCE
IN WIRE SERVICE
Postmaster General Burleson
Makes Letter Public Telling
of History Making Invention.

Washington, Dec. 12.-Postmaster
General Burleson today made puDlc
a letter from Theodore n. Vail, pres
ident of the American Telegraph and
Telephone Company announcing the
invention and development by the
techical staff Of the Bell Bell system
Iof a practical system of multipieX tel
aphony and telegraphy by the use OF
which it is now possible to increase
MANIFOLD the message carrying ca
pacity o., long telephone and tcie-
graph wires
With this new system" said Mr..
Wallis letter, four telephone conver-
sations over cne pair of wires are
simultaneously carried in addition to
the telephone conversation provided
by the ordinary methods. Thus, over
single pair Of wires q total of i've
telephone conversations are slmul-
taneously operated, each giving serv-
ice as good as that provided by the
!! circuit working in the ordinary way.
"a number ot years ago, we devel-
cpcd the phantom circuit arrange
n1ent by which three telephone cir
cults are obtained: from two pairs OF
wires. Now by our nlultiDleX methods
we are enabled to obtain five tele-
phone circuits over one pair OF wires,
that is, ten simultaneous telephone
c-nversatioEs from the two pairs OF
wires which formerly could te used for
only three simultaneous conversations.
In telegraphy as we'll as in tele-
haQc
attained by the new system. BY COM
bining two telegraph wires into me-
tallic circuit Of the type used for tele-
phone working and by applying our
new apparatus and methods to this
metallic circuit, we have enormously
increased the capacity OF the wires
for telegraph MESA gos without IN any
way inlpairing the quality Of telegraph
working.
.'The nature Of these Developments
| is such that the desired wires may be
used partly for telephone and partly
for telegraph A pair OF wires is
available either for five simultaneous
telephone conversations or for 40 81
multaneous telegraph messages or
rtly for one and partly for the 9TH
er.
From the nature Of the apparatus
and the methods employed the system
IS not particular! advantageous on
short lines either telephone or tele-
graph. On long lines its application
will be extended Immediately but its
introduction must necessarily be grad
ual on account OF the nature Of the
apparatus required and the rcarranSe-
ment and adaptation Of the lines
themselves and their associated appa-
ratus to the new methods OF work
ing. It is not too much to character
ize this new system as marking an
epoch in the Development of long dis
tance telephony and te!egraphy.'
Mr.. Vail said that an installation of
the multiplex telephone system be-
tween BALTIMORE and Pittsburgh had
been in service for more than
month Ion Monday of this week -
he said, accompanied by a party OF
distinguished government and te.e-
phone and telegraph officials I made
ar. inspection Of the system ct Balti-
more anG, a test Of the service provid-
ed between baltimore and Pitts
burgh. All Of the party were delight
ed with the successful working of the
new system and the evident skill which
had been shown in developing it. "