The New York herald. [volume] (New York [N.Y.]) 1840-1920, 1857-05-07
TIE TRANSATLANTIC TELEGRAPH.

Cable IanufactOry-Imsula ting and Testing
the Wir-TransnAisslon OF Continuous Eiec-
From the London Herald, April GIL
The great commercial advantages which are to
accrue from the eseaolshment OF nne OF teiegra-
PHO communication between England and the great
Ameri:an continent are admitted by all. and we be-
lieve that no exertion or expense would DO c0nsi
dered too great both this the other side of tho
The great and what appear at first sight almost in
surmountable. difficulties which arise at every step
have not deferred numerous projectors nom apply.
ing their ensrgies to the solutioa OF the dimcuty:
to the calculation Of any theory, however vague or
unsound, are seldom entirely thrown away. Even
il the immediate object Of our search is unsuccess-
full facts Of great importance are sure TO transpire
during the on other Se
have turned their attention to the prolec-
ton Of an Atlantic telegraph have at length led to
tangible result, though only after very many slow
Of Years. During tbs period almost every successive
month has been hailed with an announce nent OF q
new Atlantic cable; but II is not strange that up to
tine present time shareholders could not be fOund
willing to deposit their capital at the bolt m OF the
sea, with very vague prospect Of return staring
them in the face. Gables Of all sizes and forms have
been introduced to the curious world-some 700 ex-
pensve, others not strong enough; out the large
the prevailing error The cumbrous size,. great
weight and heavy cost OF, aud the almost universal
failure which attended the earlier submarine cables,
will long be re nembered by the smarting shaIehold-
and almost impossible to lay down. The very
means taken to secure their success was. strange
enough, the cause of their destruction. It is said
that proverbs do not always hold good and practical
OF experience that electric cables certainly among
the exceptions Unity Is not strength nor is
strength security, where they are concerned expe.
reuce having amply proved that q close, strong and
sure to crush itself with its own weight in laying
down. The latest example we have of this Is In the
unhappy fate Of the ponderOus cables th which 1t
was intended to connect the opposite shores OF the
Mediterranean. They now, we ka0w, ad0rn the
bottom of that sea, lasting memorials Of the great
enterprise and little foresight of those who placed
them there, and no doubt permanent sources Of
wonder to the piscatorial inhabitants. If heavy
shallow seas il is difficult TO conceive how they, or
indeed, any can be laid down across the Atlantic,
where the depth in some places exceeds three miles
The difficulties, great Is they are, have, however,
labor, many trials, and not few failures have led
to what Is anticipated will prove successful result
company has been formed for the purpose of lay
ing an electric wire across the Atlantic, and, what
is more to the purpose, the wire intended for 1t Is
progressing rapidly towards completion.
Any one who visits the works of Messrs. Glasse,
Elliott Co, at East Greenwich, (where onehalt Of
the cable is in process of manufacture cannot fail
Undertaking and the beauty and completeness Of the
mechanical arrangements for carrying 1t ous: Apart
from the difficulties of laying down the cable those
attending its manufacture entire AMI without haw,
as may be easily appreciated. One imperfection,
however eight, in the insulation of the wires,
would render the whole undertaking abortive. If
the difficulties to be overcome are great, the means
Co.. are certainly no less So Everything that can
be done to the cable cessfu is done; and
IL the attempt to lay it down should ultimately
prove unsuccessful, we should almost be inclined to
believe that the scheme Is impractcabe altogether
The track on which it is intended to lay down the
wire corresponds very nearly with the course Of the
Gulf Stream. BY this means advantage viii be taken
of the comparative shallow table land which that
wonderful current has accumulated Ut the bottom of
the sea. The unfath0mable depth Of the central
Atlantic-the chief difficulty which had to DO CON
tended with-wil be thus avoided. The line will
extend from valents Bay, the coast Of Kerry, to
Trinity bay, in Newfoundland, q clear distance Of
1880 geographical miles, the greatest depth the
route being 2,070 fathoms, or upwards OF two miles
and half. and the average depth 400 fsthoms or
down in one length, because fine weather, on
which depends the entire success Of the opera
ton, cannot be counted upon In the Atlantic for
q period Sufficiently long. Two, perhaps Of
the service-the Agamemnon, lent by the English,
and the far famed Niagara, BY tho American govern
ment Both these vessels are being fitted and altered
in order to be ready TO ship the cable In July The
Niagara viii take In her half from Messrs. Newall's
works at Newcastle. and the Agamemnon win ship
the other from the works of Nessrs- Glasse. They
win then both steam to stated latitude, about the
middle of the n.cneed course, and having securely
joined and dropped the cable, the Agamemnon will
return 20 Valentia bay, the Niagara continuing her
course to Newfoundland. BY this means the entire
length will be laid down In about q week, or less
than ouehslf the time il would occupy II one ship
were to perform the whole voyage! Another reason
why two ships sre employed IL the great weight OF
the cable, nearly 600 tons, much more than could
possibly be carried by one. The cab.e itself co n
bines hghtness with strength. II Is rather under
thrccquar'ers of an inch IN diameter, aud Is, per
baps with the exception OF that used for the Black
Sea telegraph, the smallest ever employed. II IL
peculiar In It's construction, differing chiefly from
other submarine cables In its outside covering. This
Is composed Of vast nu nber OF very small wires
twisted together. instead OF a few thick wires,
which are usually employed. BY this means great
fexibiity Is given to the cable, AMI its weight Is
lessened and lis strength increased. But In order
10 understand it, construction thoroughly II will be
Necessary 70 make eursory visit 10 Messrs. Giasse
and Co.'s factory. The con tuctor In the centre
sists OF single copper wire, Itch OF an Inch In
diameter, composed Of seven No. ~ wires twisted
together. THIS Ia covered with three coatings of
euatta percha, which increase the diameter of the
whole TO about tbreeeighths OF an inch. Thus far
the process In performed by the Gutta Percha Com
pany, whose patent Tor covering wires with that
substance Is as ye, unexpired. The insulated wire
N, therefore, received ut the works at East Green
wich in perfect state. The next process which 1t
undergoesis that Of covering with tarred string.
chm. psSySed ~s FIVE
the machLe while the covered wire Is being passed
through il, revolving at the amazing speed of 800
revolutions per minute, covering tightly and ciectu-
ally every portion Of IL In q surprisingly short space
Of time. IL Is ready for coating with the outside
covering of twisted iron wires; the strands for
this purpose, composed Of seven No. ~ iron wires
t~isted into cord, ere prepared In another portion
Of the factory. They are then wound on large bob
bins. each containing some miles, which are con-
vyed 10 the "clcspg" machine, where the final
coating OF wire IL twfted 10 the cable. This ma
chine consists Of q horizontal framework OF iro3,
about ten or twelve feet Ia diameter, round the eige
Of which ore pla,cd eighteen frames for like num-
Der of Robbins. The strands OF wire from the bob
bins are al carried up 20 the top OF the machine,
and meet at an aperture through which the core OF
the cable IL passing. The frame, when set In mo.
ton, fevolyes at the rate OF fifty In minute, and
tightly and regularly twists the eighteen strands
- n H.