New-York daily tribune. [volume] (New-York [N.Y.]) 1842-1866, 1858-10-07

With the eco miles Of cable, amounts were:
l............ .s part part. s...''. - psTt'
3.......... -39.5 parts 6....-.--.... .39.5 parts
rr.T or The ENTIRE CABLE oS BOARD TIE AGA
Mfnsos AND SiAeiEA-vIz: $500 NILES.
Battery at AgamemnOn end.
/. Current entering the cable, the Niagara
end being disconnected. .......-......4s parts.
. Niagara end 10 earth. l9l uarts
3. Current flowing out al Niagara end to
eariA...'.- ,..........'-'" "..-......lJi parts.
Battery :, Niagara end.
4. Current .ng cable, Agamemnon end
being disconnected ....3js parts
j. Ane-cmnon end 70 earth. ....---.....-.W parts
g. Current flowing ont at Agamemnon end
to earth :-..----...- -.-.ii parts
Indicating considerable leakage Oh board the Aga.
meUnOn.
] an also informed that the currents through tie
cable even Immediately after i was submerged, were
80 weak that relays useless and that not one per-
feet message was recorded by them, everything that
was received being read from the reflections OF the
gaymometer.
By comparing the above data with those Of the new
cable now making by Messrs. Glasse and Elliott FIR
the Electric and International Telegraph Company
the amount ofcuTrent which entered the 900 miles Of
cable when disconnected at end should not have
exceeded on % parts instead of - and 81 parts.
The inference by rough calculation, therefore, u
that there was aul, offering resistance equal 10 W0
or 800 miles Of cable situated at adistauce, about so
miles from end of the -OO-Ine coil on board the
This, however cannot he the fault first alluded TO-
situate al about q miles from Naentia but may have
been the one which caused such alarm when the ships
were 500 miles from Ireland and when the signals
ceased altogether and never certainly recovef.
1t not at all improbable that the powerful currents
from the large induction coils have impaired the ins-
laiion and that had more moderate power been used
the cable would still have been capable OF ansmtting
messages.
To satisfy myself this point attached to the ca
Die piece of gutta-percha covered wre having first
made slight ncision in the guita pcrcha to let the
water reach the wire the wire was then bent 80 n 10
close up the defect. The defective wire was then
placed in jug of sea-water and the latter connected
with the earth. After few signals had been sent
from the induction coils into the cable, and, conse-
aucnty, into the test wire, the electricity burned
| through the incsion, rapidly burning hole nearly
one-tenth of an inch in diameter.
When the full force Of the coils brought to bear
on the test wire by removing chem from the cable and
allowing the electricity only clannelviz: that OF
the test wre-the discharges, az might be expected,
burned hole in the guta percha under the water,
half an inch in length, and the burnt gutta percha
came floating up to the surface.
The foregoing experiments prove that when there
are intersections in the insulating covering there 10
very great danger arising from using such intense
currents. :,
Tie size of the present conducting strand IL too
small TO have worked satisfactorily even had The insu-
lation been sound. With strand of larger dimeil-
sons less intense currents would be required and both
speed and certainty increased.
1t is not, however altogether impossible that some
ineligible signals may yet be received through the
| cable, as stated Ill my previous communication.
c. y. yARLEY, Electrician Of the Electric
and international TeesT aph Co.
To the Chairman and Directors of the Atlantic Telegraph Co.