, 1889-05-15

posite directions duplex, after which the
ordinary instruments and the phOnOpore
were worked together in the same direc-
ton duplex. The final experiment con.
sisted in the ordinary telegraph and both
the phonopore telegraphs being worked
together simultaneously through the single
line. The three messages were perfectly
transmitted although some of the opera
tors had not previously used the phOnopO-
rlc instruments. These experiments prov
ell not only the complete possibility OF
Simultaneous working, but that the phone.
pore can be arranged to work ordinary
telegraph Instruments, and that when used
in duplex or quadruplex work it requires
no special regulating or balancing. They
also proved that any wire already provided
with an ordinary service can instantly be
duplexed by merely attaching the pho
nOpore instruments. On II second arti-
fetal line there were installed two
harmonic phOnop0re sOunder telegraphs,
constituting a duplex service with.
out any arrangement whatever to bal
ance the lines, and working through
a resistance equivalent to that of about
5000 miles of telegraph wire. Messages
were prefectly transmitted through this
line in both directions at the same time.
Turning next to the installation at st.
Pancras, we find that on the ordinary
telegraph line wire between London and
Derby, which is about $50 miles in length,
ordinary Morse telpgraphs are working
through ordinary relays in the ordinary
way. AT the London eud of the wire there
are two telegraph stationS-namely, the
terminal station and an intermediate
station about halt q mile away. The
phOnOpore is installed in derivation on the
line at a point between these two stations
about ten yards from the terminal instru.
ment. The distant phonopOre is placed
also in derivation in the wire at Leicester
about 30 miles from the distant terminal
station at Derby and 100 miles from that
III London. This phomOpOre post is there
fore on a branch line from "a point III the
main line where there is no ordinary
telegraph instrument. The phonOpOres
installed are two p%hOnopOre recorders,
each Recorder being q complete post in
itself, the phonoporic messages being
printed in Morse signals. 1t was shown
by IL galvanometer that there was a great
deal OF ordinary telegraph work going
on upon the line during our visit, bat
notwithstanding this the phOnopOric messa-
geS travelled III the same wire absolutely
independent of the ordinary messages.
Conversations were held between the
operators in London and Leicester, and
messages were freely sent aud replies an
freely received during our stay. In
addition to the facts demonstrated in the
artificial lines, this installation proves
beyond a doubt that the phOnopore service
Is absolutely unaffected by the ordinary
te~legraphs, even when installed between
two ordinary telegraph stations less than
a mile apart. 1t also shows that the
phonopOre service is so entirely indepen-
dent Of the ordinary service that it may
be worked at points where there are no
ordinary telegraph instruments, although
at other points in the same wire ordinary
telegraph instruments are at work. The
first series of experiments demonstrate the
wide range of power possessed by the
phonopore the second indicate that the
system is ready to take it's place in every
day work, while the whole stamp the in.
Ventlon aS one of very high order and of
singular merit.-Times.