East Saginaw courier. (East Saginaw, Mich.) 1859-18??, 1863-09-30
THE PERSIAN GULF CABLE.

THE PERSlAN GULF CABLE.
II has often been said that the At
lantic telegraph cable was not lost, for
the experience obtained would con-
tribute largely to future successes
This proves to be literally the fact
The great line of telegraph now con-
structing, to connect London with In
dia, contains submarine section equal
to 800 statute miles, which is be-
lieved to be the nearest approach yet
made to scientific perfection. A de-
tailed description Of this enterprise,
given by the London Times, brings out |
the causes Of the faiYuSrsss of r}ieg At 70
tic cable, and the precautions now la
hen to avoid the recurrence of such a
Disaster
Every operation in submarine tele-
graphy-even the great Atlantic line
has contributed its quota of valua-
bic experience for, though success
fully laid by Sir Chas. Bright and the
assistant engineers, in spite of its i'm
perfect construction, it was destroyed
by the iniudicious electrical treatment
it received after submersion. The
| fact is now well established that the
cause of the failure of the Atlantic
cable may be considered as set at rest
forever. The insulation of that line
was not very perfect, as may be mag
med from the infancy of the science
at that time, but yet the electrical
power used was such as would infalli-
bly, break down even the most perfect
cable manufactured ut the present day.
OF this our readers may judge when
it is stated that the large induction
coils FIRST USED In signaling between
England and America were probably
equal in electrical power to 1000 bat
terry cells, while now il is found mex
pedient to use more than two or three
cells in working the longest subma-
rine lines in existence. Some of this
great power was no doubt used in the
vain hope Of forcing signals through
the line at a greater speed than the
very unremunerative rate at which 1t
has alone been found possible to COM
municate through an unbroken length
of 5000 miles; The result was disas-
5 trous, but the experience, though
dearly bought, has proved of great
1 value. 1t has taught electricians the
value of moderating the power used
r in working lines, and above all has
3 pointed out the imperative necessity
4 Of having no single section of sub
-,
, length. To lay long submarine cables
, in a continuous length, without inter
mediate stations, has been found to
, answer no other purpose than that of
greatly diminishing the speed of work
{ ing, and multiplying every imaginable
risk both Of manufacture and SUMNER
f sion. The India government, acting
under the iudicious counsel of their
: scientific advisers, have wisely deter
mined to divide the Persian Gulf into
, three sections, though its total length
will not exceed l,5009 statute miles
!, The Red Sea line was destroyed by
faults of another character. Being
n laid without any allowances for slack
p that the cable might conform the more
9 readily to the Irregularities of the bot.
tom, the suspended portions become
. loaded with barnacles and coral, and
crumbled from its own weight.
. To obviate this cause of danger
: which in the above mentioned lines
5 has probably occasioned loss of pro.
: sterling, the Persian Gulf line is cased
5 in II No. guage hard drawn iron
: wires, thickly galvanized, so as effec.
4 tuaily to prevent their corrosion. But
o in order to secure more eiiectually the
n permanent stability of the line, til,
whole finished cable is thiclly coated
4 with two servings of tarred hemp yarn
Z overlaid with two coatings Of patent
\ composition invented by Sir Charles
O Bright and Mr.. Lattimer Clark. The
1 composition consists Of mineral pitcl
: or asphalt. Stockholm tar, and pow
dered SILICA, mixed in certain proper
y tons, and laid on in n melted state
+ While yet warm it is passed between
f circular rollers, which gives it a round
|. smooth surface. When quite cold this
forms massive covering Of grea
strength and perfect flexibility, totally
" impervious to water, and incapable o
= being destroyed by the minute animal
: culp which exist in such an Abundance,
u in warm ATTITUDES, and which, wher
= the cable is not protected against theil
y attacks, eat every atom of hemp, as il
; the case of the cable laid between
81 lo.,n,a
n Another important fact is stated
e that wire varies greatly as much al
o fifty or sixty per cent. - in its capacity
: for conducting electricity. The cable
: for the Persian Gulf is so well selected
g and so well protected by gutta percha
d and compound, that the loss by leak.
e age is scarcely appreciate by the
: most delicate instruments. To sucl
n minute perfection has the system o.
i testing adopted by the engineers been
II carried, that the loss of one thousand
/ millionth part of the crrent by leakage
$ could be detected and estimated. The
# cost of this submarine section will ex.
@ ceed 81, 100000.
1t is ony little more than year
o July 6, 1862 since Mr.. Seward, as
Q Secretary of State, wrote to Mr.. Ad
! ans, our Minister to England, as fol