Nashville patriot. [volume] (Nashville, Tenn.) 1858-1860, 1858-10-12
Report on the State of the Atlantic
sssz Telegraph Cable.
LONDON, Sept. Is

report on the state OF the Atlantic
gssz E Telegraph Cable.
LONDON, Sept. Is.
arrived at Valencia on the evening of the
5th inst, when i found that no words had for
many days been received through the cable
from Newfoundland
On the 9th, 9Th, Sth 9th. and 10th tested
the cable at intervals in four different WAYS
to ascertain its condition. The following are
the results:
]. There is fault of great magnitude at
distance OF between 245 and 800 statute miles
from Valencia. but the locality cannot be
more accurately ascertaned until portion
of the cable, 20 or 80 miles in leng h. has
been tested against my standard of resis-
tance, and until the log has been consulted to
ascertain the amount of slack paid out /
would suggest that the piece of cable at
Greenwich be carefully measured and tested
against my standard, in order to obtain the
most correct estimate of the distance of the
fault Assuming, however, that il is 27O
miles, and allowing % per cent. for slack. il
is possible thai the chief defect is in shallow
Water-410 fathoms.
2. The copper wire at the faulty place above
alluded to does not touch the iron COVERING of
the cable, as is proved by its forming volta
mic element, which gives rise to a continuous
positive current from the copper wire varying
very little in tension. 100
3. The insulation of the wire between Va
lentia and the fault is perfect. or at least con-
tains no defect OF sufficient importance to be
perceptible, or to materially influence the
working were the cable otherwise perfect.
4. The copper wire is continuous, and con-
sequently the cable has not parted. Faint
signals, or reversals, are still received from
Newfoundland, but the power used will short
~ cut away the exposed copper wire in the
fAnlt MI hxya 1t Il
The actual resistance of the fault appears
to be at least equal to 10 miles of the cable,
but is most probably greater
Taking 1t at its lowest resistance viz, 10
miles and assuming that Newfoundland is on
ly using $50 cells of Daniels battery. the
strongest current received thence during nv
stay was only 1-24th part of the force that it
should be were there but this one fault When
1t is however, borne in mind that on the
other side they are probably using more po-
wer, and also that the defect first alluded tc
probably offers more resistance than that
assumed, viz. 10 miles, it is evident that there
Is another and more distant fault, the approx
innate locality of which | could not pretend
to estimate at this end without being able to
speak to Newfoundland
FROM authentic data shown to me at Va
lencld am OF opinion that there was'a fault
on board the AgamemnOn before the cable
was submerged, at a distance of about 500
miles from one end and $40 from the other.
Here follow some data
L am also informed that the currents
through the cable, even Immediately after it
was submerged were so weak that RELAYS were
useless, and that not one perfect message was
recorded by them, everything that was re-
celved beng read from the reflections of
galvanOmeter.
RV cOmOarinor bo aho 5,+o q
the pew cable, now making by Messrs. GIasse
and Elliott for the Electric and International
Telegraph Company, the amount of current
which entered the | 200 miles of cable when
disconnected at one end should not have ex-
ceeded or parts instead of IS and SIS
parts.
The Inference by rough calculation. there
lore, Is that there was a fault offering a resis-
tance equal 10 1000 or 200 miles of cable
situated at a distance about 500 miles from
one end Of the 200 mile coil on board the
Agamemnon.
This, however, cannot be the fault first al
luded to, situate about 270 miles from VaIen-
TIA, but may have been the one which crnsed
such alarm when the ships were 500 miles
from Ireland and when the signals ceased al
together and never certainly recovered.
Ii is not at all improbable that the power
full currents fiom the large Induction coils
more moderate power been used the cable
would still have been capable of transmitting
messages.
TO satisfy myself on this point, attached
to the cable a piece of gutta percha covered
wire, having first made a slight incision in the
gutta percha to let water reach the wire: the
wire was then bent so as to close up the defect
Inc detective wire was then placed in Jug of
sea water and the latter connected with the
"a flyr cfpr l. L,.I 1,
from the Induction coils into the cable, and
consequently, into the test wire, the electrici-
ty burnt through the incision, rapidly burn
ing hole near One-tenth of an inch in dia-
meter.
When the full force of the coils was brOu pht
to bear on the test wire by removing them
from the cable. and allowing the electricity
only one channel, viz that of the test wire
the discharges, as might be expected. burnt a
hole IN the gutta percha under the water hal
an inch in legth. and the burnt gutta percha
came floating up to the surface.
Ihe foregoing experiments prove that wher
there are lmperfectiOns in the Insulating GOV.
ering there is very great danger arising from
using such intense currents.
The size of the present conducting strand
Is TOO small to have worked satisfactorily
even had the insulation been sound. With
strand of larger dimensions less intense
currents would be required, and both speed
and certainty increased
IL Is not, however, altogether impossible
that some Ineligible signals may yet be re
ceived through the cable, as stated in my pre-
vlous communication
- CT. VARLEY,
Electrician of the Electric and international
Telegraph Company.
10 the Chairman and Directors of the Atlantic
Telegraph Company.