New-York daily tribune., 1858-08-03

Uncovered OF boA TIA. tie eectirui:y bad erere'5
ceased.
TIE bet explMstion of the failure which 4"
bssn offered "a from M. Bogardrs o! tbs City' Az
1epth two miles the water hlterins through Tue
wire covering of the cable exets on the gu''
rsrchs within pressure Of 6ys thousand pounds
rer square incb, ard greatly reduces It's orSin~
bulk. Tie strands of the wiie covering are thus
LEE unsust.ined, AID made to overlie each otner
In tti po..ion tie strards Of the wire covering are
.lsckered AID Tie autta psrcha and telegraph wires
beire teo ves1 TO sustain The strain length"i'e'
ale broken asurcer.
Tie .trsin upon the cable is proportional to shs
lepeth cf the portion hanging below tue point AZ
which tie strain takes place. Consequently 'ne
strain decreases in goiug downward, wniIe
On TIE contrary, the compression oil the
suttspe in the cable increases With the eep'a'
and At come blight from the bottom OF tho oceaa
tie eu.ta -perchs is sufficiently compressed 10 allow
the oysriying Of the covering straEds, While there Is
sill eroush of the cable hanging below to break tue
conductor By its weight. hebreakiug hss in some
ins.snce. very likely, occurred at thispoint From
few expe riments with hydraulic press and SIX
feet of the cable the company might have learned
what they have now demonstrated In more eN-
pen.ive way. that the covering strands Of ieNele
cable intended for great dep.bs must not De wound
around helca'ly but laid parallel to the AXIS
Inthe recent triatbe third breaking happened sud
denly few feet below the stern of the Agamemuoc,
the strain indicated by The dynsuomster
being as low as 2,l0o lb. The agents
Of the C, mpany, unabe to explain the cause as
crbe this accident to some my sterous deiect IN tue
cable, as notwithstanding the most careful e1am'-
patlon Of the broken end they were unable TO de-
tect ary haw in the iron covering. The Cause +"
ore which we explained year ago. A cable ca
liable Of sustaining few tuns in state OF resI'
viii break under weight of as many hundreds OF
pourds, Il it is suddenly jerked up BY the raising
of the stern of the vessel from which it is PAD out'
The dynamometer adopted by the Company con-
sists of weight of about tuu hanging
from the horizontal portion OF the cable De-
tween the machinery and the last pulley
over which the cable passes cut N the
ship As long as the strain increases gradusily
with the deepening Of the sea, this weight is aug
merted more and more, ard its elevation indicates
the strain. But when quick jerk occurs, the in
ertia of the weight exerts, during portion of a
second an enormous tension, which breaks tbs
cable before the strain is shown on tie instrument.
The new machinery Is lighter than thai used last
year. and for this reason is better; but 1t is even
worse in principle. a few days more, and the
news Of new failure will make it palmer still that
the operations have been conducted by men IN
qualified to overcome the difficulties they had to
contend with. Still, what has been done with in
adequate arrangements demonstrates that the At
lantic Telegraph is feasible thing, and that q
more scientific way of proceeding may insure com
plete success.