Richmond enquirer. [volume] (Richmond, Va.) 1815-1867, 1857-09-08
UNEXPLAINED
From the National In,elGgencer.l

THE ATLANTIC CABLE.
We have already alluded to ;ns fact that the contn
zen, occurrence OF the particular accident which
proved fatal 10 the recent experiment in laying the
Photographic cable had been previously indicated 10
able scientific paper by Lieut.. j. NJ BROOKE, of the
Navy aud which appeared in this journal early in the
month of May last. We to-day have the pleasure o:
presenting TO our readers from the same intelligent
source the following instructive observations bearing
upon this topic. we'll others connected with the
practical execution OF the great work, OF whose even
iua accomplishment it is gratifying to observe that
Lieut.. BROOKE does not despair, though his scientific
knowledge enables him to foresee even greater diff
culties and varied casualties than appear to have
been spprehended by those who FIRST embarked in the
enterprise.
WAsHiSGros, September g. 1857.
10 .he Editors of the National jgte3ligencer:
The late unfortunate result of the a,temp, to lay the
telegraph cable hos given rise to serious doubts as 10
:oe eventual accomplishment Of the project The
pspes of the day teem with fsncitul suggestions
70 the causes Of the mshap. II may be shown, how.
evsr that neither mysterious nor insurmountahle OBJ
acles ere opposed to successful result; for in
~ particular the circumstances attending the opera
,oc-the movement Of the cable tie temporary in
.ar.upton Of the passage OF the electric fluid, and
lie parting Of the cable, in certain contingency
we're clearly indicated several months ago. In the
esssy, ocean Telegraph" published in the Intelli
Sencer, and from which quotations bearing on the
management of the cable have been recently made
the tendency Of the cable TO snk in the direction Of
ia INCLINATION was pointed out, and in this black
Set is found satisfactory explanation Of the re-
rnsrkable under that refusing TO touch the
dsep.sea sounding lines, laid in wait to seize and
bea. away the cable on which hung the hopes of ma.
-,nduarG, by inclination OF surfaces consequent de.
composition and decomposition OF forces, applies az
well to the descending cable sslo the sailboa which
eats INFO the eye Of the wind"
We may reasonably anticipate waste if a cable
Do permitted to dsscend at inclination of perhaps
;hrty degrees from the vertical-set king the swift;
90: line o. descept-approximating the cyooids
curve. Aud the secret OF the apparently anomalous
interruption of continuity lies in the following para
graphs OF the essay:
Il, remains to be- seen, 10 practice whether these
various materials have been most advsn,aGeously
combined.
Suppose that the copper and iron wires were
straight and parallel in that csse since the relative
6uctiiity Of these metals is about four 10 FIVE, in
favor Of the copper the iron wires would practically
bear the sran, relieving the copper add this, with
out regard TO change Of form III the core Of gutta.
percha. But in the cable now IL process OF manufac.
;ure the outer wires make whole the foot.
It becomes, then, a serious question, whether by
strain or the pressure Of FIVE Elk thousand pounds
70 the square inch, the core will DO compressed or al
tered 10 form. The water penetrating between the
iron wires will surround each part Of the GABLE and
on Them individually, exe-, its powers of compress
siop Ii the gut:a perchs yield, the iron wires will
become locse-wiil extend-and the strain ill come
on the straight copper. dr0uing Il; and although it
breaking, any such process involves rick.
"Tbe character OF the curve assumed by the cable
on is way the bottom will depend upon the velo
city Of i;s descent and the speed of the ship.
III the CABLE when extended horiz Tally upon the
water sirks faster than the ship rune the convexty
OF it's curve will be towards the bottom; the upper
portion, nesry vertical, will descend more directly
aud therefore more rapidly, towards thu bottom; the
.ower portion will consequently be deposited IN
.,on :kc bottom"
The condu ting wires broke the gut:a percha,
stretching with the outer wires drew the broken ends
apart, aud continuity then interrupted. Bat
when .ha, portion of tho cable approached the bot
tom 1t became slack. The cn6is rel be deposited tn
,Gr,s upon the bottom" Then the gutta perchq, re-
!vved Of the stran, by virtue of its elasticity con.
tracing, drew the broken, separated ends of the
Quoting wires together, and continuity rs-estab
shed. This establishment Of continuity is strik.
ing proof of the fact that the conducting wires were
broken, while the guta. psrcha remained unframed.
Had it not been the interruption would
have been generally attributed to abrasion Of the
gua perchs aud tAeerror of construction could haze
rem .,hed unernosed.
Iu view Of these facts, fulfilling they do, even in
detail, predictions made months ago. forming part Of
an essay which, upon equally good grounds, predicts
the eventual accomplishment Of the enterprise, we
may feel assured that on day not far distant we
shall have living ocean telegraph.
j. NJ. BROOKE. 1t. U. s. Navy.