Daily State sentinel. [volume] (Indianapolis, Ind.) 1861-1865, 1865-06-17
DAILY SENTINEL,
SATURDAY MORNING. JUSEi1.


The London Telegraph Of Nay 23d has The
folloving interesting account of abe preparations
on board the Great Eastern for laying the ocean
telegraph cable:
purERkxcrs BrrvErs 1858 AND 1865.
vssst YES paid TO the Great E.s'ern q fev
days . nee b, large party Of the Director
frieud.. and IL nay be sid that all uho under
stood the preparations shich they cav came away
With greatly strengthened confidence IN the
future Of the new cable Since 1855. when the
fsst Atl-ntic Iine laid. the advance that
has been made by the sceotic world toward con-
pretending electrical phenomena 10 very great.
IL hss been said, BY msn veil qualified 10 speak
on she subject. that electric sccnce has passed.
since that time. from its childhood 10 its matur-
ity. 50 far a. the phenomena connected with
long electric circuits were concerned. We bad In
1855 no knovledge whatever The instruments
IN common use were un-uited to receiving sig
nals through gre., length OF cable; the neces.
sity of providing for the conductor insulation
so perfect as 70 approach an absolute condition
vas insdequstely appreciated. The best pre-
hni7ary te.t for a long cable had been de-
vseI, and the old Atlantic telegraph was laid
without having been subj -cted TO any searching
test on shore. Everybody bad advice TO give
concerning the management OF the wire. but no
quent experience has shown to be necessary.
When the Signals began 10 fail the battery power
vas sugmented aud electro magnetic induction
coils, which rapidly helped on the destruction OF
the conductor, we're pat in circuit No one
thought Of " nursing the cable--of humoriDg
ils feeble attempts at srficulste uttersnce, and
OF finding out what il said rather by listening
acuteIy than by constantly calling on il. 10 the
language of the Victoria gallery. 10 speak up"
The old cable. however. Is dead and gone; part
of il has beenspickcd up and applied TO gnoble
uses, ss a race-h horse past his work may be put
into the shafts of H4nsom; part Of il has been
abandoned and lies where il may rest till the
end OF ti1e. n the " dark unfathomed caves
OF the deep sea. Let Us turn 70 the practical
present.
SCENES on BOARD THE cREAr EASTERN.
The Great Eastern looks just now more ike
an engineers workshop than q seagoing ship
The vast eIpanses OF her deck are covered With
WOODED sheds and piles of timber. There are
smihs forges below. and between the decks you
might fancy yourself ia a mschinist's factory
The great engines OF the ship. il is true have
lost the bright look of machinery which s in
constant use: and the huge dull masses Of iron
seem asleep. or in trance Id you descend the
ladders which lead 20 the boilers and furnaces
an expedition which is more like going down q
niue than any other TO which il can be compared
solitude. add cold; but in those regions of the
vessel where the cable is being shipped and
watched, there IL every sign of keen, vglsnt
intelligence. When you understand what is
being done. you see something more than this
that scientific foresight Of the highest order ti-
reefs ever step; and that the thick tarry rope,
coarse and rough to appearance. which lies coiled
away under the water 10 the tanks of the ship, is
manufactured scanned. and tested with as much
Il nat
omer's observatory. or the most delicate appsrs
tus Of fragile glass applied to The careful
experiments OF chemistry
THE SCIENTIFIC Tssr.
IL seems impossible that there can be any fault
in the Atlantic cable when the Great Eastern
goes sea. To say nothing Of the tests applied
20 IL At the mandatory, il is tested not only
after il has been taken on board. but during ia
delivery into the ship. As IS length is
brough. alongside. one end Is connected With the
coils already on board, and the other end with
the instruments in the testing room. The Circuit
il thus made through the whole extent Of the
coil. the portion board aud the portion along
siie. he process of hsuling 10 then commences,
and the insulation is continuously observed The
Instruments ia the testing room record the small
e.; deviation from absolutely perfect insulation
IL will be understood that an insulation which
sh I'll be quiie perfect, as an electrician under
metal -eptratelbv means OF the purest glass and
enclo>ei IN the dryest atmosphere that can lie
Obtained. will II hsFged with electricity lose
that electricity after a time. la speaking of in
sulati0n We must. therefore. be understood to
mean an Approximate condition; but the APP
proximtrion in the case OF the new Atlantic
e,hle comes SO near To perfection that this rough
tarry roDe is scientific wonder
The at dying pulsstiOn of the old Atlantic
thr -
vsnic battery consisting Of two hundred and forty
cells The subm ,rine telegraph from London
TO Amsferds m il habituallv worked with bat
tery OF fifty cells. and such battery is com
msnly used for the other submarine lines of Eu-
rope Signals have been repeatedly sent through
mpre than thirteen hundred miles of the cable
nov on board the Great Eastern by means of
one cell g ,lvanic currents SO feeble that they
could not have been felt by the hand. and might
have been passed harmles>ly through q circuit
completed by the operators tongue. can be
used 10 convey messages along a length OF cable
that would very ne.rly stretch from London TO
Sc. Petersburg. Over needle Instruments such
as those in ordinary use for land teegrsphy.
current from one cell would be powerless.
To record such faint pulsttions of electricity
IL is necessary 10 use Professor Thompson's mir
ror OF galvsnometer. This besutifuI instrument
consists of mirror about the sIe of four
penny piece. made Of microscope glass. and 30
thin that il weighs only grain. On the back
OF this mirror minute magnet is fixed. and thus
supplemented. IL Is suspended silken fore to the
heart OF coil of wire. ID q any current pass
ing through the coil defects the magnet aud the
mirror along with il A ray of light refectei by
the mirror tails a scale. distant about eighteen
or twenty inches, and reveals its fainiest move
msnts ID ferent combinations of these move
ments represent the different letters of the slph
bet. aud thus the apparently cratic wsnderings
of ray OF light are IN ode convey intelli
gence. An instrument Of this kind is consts nry
used to te~t the cable ~ il is hauled on board:
AMI II fault had exsfed il could not have
psssei withou, detection. Up 10 this time, when
there are ON board ;Ae ship alongside $40 miles
OF cable, fault has been discovered.
THEINHERsIOS.
The mtchinery tor paying out IL not yes on
board. but i being Put together at the Green
wlch WORKS The process of immersion will take
about fortnight The beginning of the shore
end slll be laid By s small vessel. which will
meet the Great Eastern about twenty miles from
the Irish coast The cable will then be passed
on board, connected With that 10 the great tanks.
and the big ship will begin her voyage TO The
uDntlated this process OF cutting and joining the
cable appears verT mysterious but the engi.
nesrs. who are used 10 the work face Il without
any hesitation The joints DO not really endan-
ger either the Insulation or be strength of the
cable az wherever thew ara made ths o fs-nsl