The Washington union., 1857-05-09
the London of april y.
THE GREAT ATLANTIC SUBMARINE TEL -yGRAH
CABLE


CABLE.
About mile or so below Greenwich stands the sctory
of Messn Glass Elliot where the great subn ulrine
cable by which IL IL hoped to connect England with
America Is in rapid Of completion The rolls OF
wire tons of hemp yarn, and singular looking drums
from the Gutta perchs Company, which necessarily
pouring into the works betoken the presence OF
sual kind of manufacture and this idea quite boroe
out by glance the premises themselves The
first object which attracts the visitors attention enter
ing yard the bulk of cable already completed
On each side of the path two large circular docks or
pits in which about six hundred miles piled away in
four massive coils each thirty five feet in diameter 1t
appears manageable and supple the men drag 1t
from the building in which it is manufactured that it is
difficult to realize the fact that the greater part OF Its
bulk is iron wire, that light and htooking rope
of that kind is intended to form perpetual medium OF
communication under the 1000 miles of of the deep
est and stormiest seas in the world
Before entering further into the subject. may
well mention that the whole cable being constructed in
two equal portions being made at MesSrs. New
all works Bkenhead, and the other at Messs. Glass
& Elliots at East Greenwich The for this sub
division is that it quite impossible for manuac
tory complete such gigantic undertaking within the
allotted time Each firm is bound by contract to have
ESQ miles ready for shipment by July, and many
miles they get completed in that time. AL
ready the two manufactures about 200 miles have
been made Glass Elliot produce at the rate of 20
miles per week. but with additional machine in course
of erection they will in few days be able to increase that
amount to 100 miles. We believe both firms expect to
have about 400 miles completed within the period spe
cited in their agreement
The half of the cable made at Newalrs works viii be
shipped in July board the Niagara American screw
fgate the longest and largest vessel of its class yet
built She viii be accompanied for the occasion by the
Mississippi fgate The line made at Greenwich will be
coiled on board the Agamemnon, which will also be
companied by Of largest steam-fgaes to assist
in laying down. The four vessels will proceed in
pany to the of the Atlantic where the ends of the
cable will be carefully joined and each ship viii make
the best of its way to its shores the Niagara steam
ing to Trinity Bay Newfoundland the peninsula Of
Avalon and the Agamemnon to Valencia Bay, county OF
Kerry the southwest coast of Ireland BY this method
the whole cable is expected to be laid in week ten
days at Five miles Of the cable where it joins in
centre will be made of steewire to enable it to bear
the great strain at starting. For fifteen miles from the
of Ireland it will also be made Of immense strength
and thickness insure it from injury from ships
chors The precautions also to be adopted at
the other extremity at Newfoundland, though only for
five miles distance from the shore the water there is
very much deeper 1t is intended TO sink the cable
the extensive plateau bank formed by the Of
the Gulf srsam its northern side The greatest depth
| here is q 100 fattoHs, pr nearly two miles and half
The average depth Of the whole route is l400 fahoms
or little than mile and half The direct dis
from Valencia to Newfoundland is l690 geogaph
ica miles between 400 and 500 miles of cable
allowed for s'slack' and casuaiiiss
The Atlantic cable, of the construction and ultimate
destination of which have thus given an outline is
beyond all doubt beautiful specimen Of manufacturing
skill possesses several essential requisites Its cost
believe is only fl00 per mile Its weight only one ton
per mile 1t is contracted for to bear strain of tons
cwt but it is stated to stand with safety Its spe
cfc gravity is between and A. its diameter is small
and it is flexible ordinary rope These great
advantages but the set-o the other side are
and most mporialr. in the first place, there is no
wire for the return current and the conducting wire H.
self is ridculoHsy small tl-l6th of inch in diameter
when it is considered that it intended to carry cur
rent for nearly 5000 miles The latter most serious
fault so ALSO is covering the outside with SO fine de-
scrpton OF wire that three months rust will entirely de-
stroy them but the greatest fault OF all is that in our
Judgment, the whole cable Is constructed on wrong
principle In previous article the subject of subma
rine telegraphic communication pointed out the er
which have already led to the destruction Of so many
cableq, and the simple manner in which they are
remedied BY Mr.. Aliens patdntE
This Atlantic cable though with regard to ehtness
and cheapness step in the right direction is still not
in the right path Whenever cable is constructed with
spiral wires round soft any strain in paying
it out must by stretching the outside wires either atten
uate break the copper conductor nure insulation
This is simple fact which those least convesant with
mechanics easily understand At the lowest compu-
taton the Atlantic cable will stretch two feet per mile
At the deepest parts where it must be laid six miles will
be suspended at one time What becomes of the con-
ductng wire during this elongaton of IL eetl 1t must
either break become attented The latter accident
believe will be as bad the former for present
win be most difficult to get the current through 900
miles of ll6h of inch wire and quite impossible
either strain pressure reduce it in any part 24h or
l32d Of inch diameter in electricity the welkest
part becomes the standard Of the whole. We do not
to say that the present cable will not succeed but
the chances against IT. and it is almost certain that
before IL has been down IL months 1t will like others
similarly constructed be perfectly useless If it does
temporarily it will not be due to the plan on which
II made, but in spite of It, The first locomotives
built answered the purpose for time and undoubt
ey locomotives though neither of these would
justify company at the present day in ignoring recent
improvements and having their engines made after those
bygone models.
1t il the same with sub marine cables The present
one though lighter, cheaper, and flexible than the
pondcrous iron coils through which shareholders have lost
hundreds of thousands retncvaby, is still made the
old principle OF scfdestructivencss Why s not
the patent adopted which, by the Of large
ductor makes the core of the cable its strength and does
away altogether with the necessity for outse spiral wires