The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1899-04-06
CABLE MESSAGES
Manner in Which They Are Sent
Through the Deep.
DIFFERS FROM THE TELEGRAPH
How the Wires are Guarded-Many
Difficulties are overcome
The Alphabet,

Even though Congress recently fail
ed to make provision for a cable to
Hawaii stlll such a line will have to
be laid before long to the Pearl of
1.-THE Pacific, if not TO Manila, and the
public may reasonably be expected 10
find interest in the manner in which
messages are sent through the deep,
thousands of fathoms down
All of us are familiar with the noisy
click, click of the telegraph instru-
ments common to all railroad stations,
and, to the experienced ear, it is no
difficult matter to tell the dots" from
the clashes of the Morse code Night
and day, in sunshine and storm, the
messages go speeding along over the
miles of iron wire strung high on the
poles and with nothing but an occa-
sonal green-glass insulator to keep
the current from slipping down to the
ground Not so with the dispatches
sent through the lines in the deep.
There the bunch of seven small copper
wires that carry the impulses must be
carefully guarded by coats of gutta
percha bindings of metal tape, and
guarding folds of stout steel, that not
even a pin-prick may leave a way for
the messages to short-circuit to the
wet bosom of mother earth on which
the cable has to lie. Unlike the over
head wires across the land it is not
possible to freshen the current with
relays Of new force every few miles;
the first impulse must thread its way
unassisted through thousands OF miles,
and it is all the more needful that
every bit of it should be saved by
every cunning device known to man.
else known to the mechanical world
that must be SO susceptible o rough
handling and still remain so delicately
intact as a submarine cable; and the
tiny air bubble or minute flaw at once
passed as unimportant in many frag
lie instrument is condemned instanter
where a subaqueous cable is concerned.
They mean possible leaks only too rap
idly developed when the current has
found them out, and to repair them
when the cable has been laid would
mean thousands of dollars and, per-
haps, days Of delayed traffic or hun
dreds upon hundreds of dollars of lost
trade
The commercial value of cable is
measured by the speed with which sig
nails can be dispatched intelligibly
cables are, TO transmit an I'M
pulse over 1000 miles in a second it
would seem to cur vulgar measure of
speed that that was even more by
many fold than would be necessary to
repeat the heart beats Of the busiest
nation; but an appreciate dignity is
given to the merest fraction of a sec
ond, and where the human mind fails
to grasp such divisions of time the cur
rent may, relatively, be classed as lag
gard
1t is Of the utmost importance IN
rapid working of submarine cables that
the separate impulses Or charges sent
into the wires to form the elements of
letters should be kept distinct and not
into a continuous current by the time
the other end were reached thousand
or more miles away. This would be all
right were it not for a well-known cleo
the earth, which sets up which is term
ed induction or induced electricity. In
sulated submarine wires act, then, in
two ways-the first as a conductor for
from the batteries and the second as a
battery for the retention of a
certain amount of 'clogging" electri
city which leaves the cable but slowly
if the line be long. In short cables this
freeing process is practically instan-
taneous, but in long ones it fingers,
checks the passage of each separate
impulse and tends either to merge
them or to destroy their distinctive
characters. 1t is like speaking through
a winding rain-spout, where the echoes
of preceding words become confused
with the following and none seem thor
oughly Ineligible. This peculiar ac-
ton of the submarine cable has long
been a source of worry and investi-
CATION for it forms the one great STUN
bling-block both to higher Geographic
speeds and the possible application of
telephony to long distance-undar water
work.
The hardy vigorous currents or i'm
nuIseS s,ch as are sent through over-