Bristol news. [volume] (Bristol, Va. & Tenn.) 1867-189?, 1869-09-24
Mode of Working the French
Cable.

n FEW Vi tue nemOcTS OF tn9 Sclontl NC
Association, which closed its session at Sa-
lem last week., have been making a visit to
Duxbary, the terminus Of the newly laid
French Gable. WHAT they saw is pleasant
~ told by the Boston Advertiser, FROM which
we make the following extracts an,
/" In an old but we'll preserved clepeoard
mansion of that quaint d town were found
the headquarters of this new and wonderful
highway. The visitors were cordially well
coined by the, manager, Mr.. Brown, and
were at once brought into the presence OF
the tting, q ,me- like image which indcs-
ted, Ia 50 mbpls, on, grar u tied screen, the
thoughts working at that instant on the
other side of the Atlantic. Interpreting
the titful tremor Of the image, or line OF
light, one inch in length, and one eighth If
an inch 10 breadth, the youthful interpreter,
who did not look the wiZ,ri that he was,
calmly read, for Transcription by his assist.
ant, message In which occurred at int
walls, the words New Orleans - Citizens'
etc, etc. While inspecting the apparatus
the members of the party received the fol-
lowing message fresh from Feance, sent Xxx
presly to them:
90 To DCxBCRY FROM BREsr,
Time $50 P. N, Paris Time
"'The company present their comrl-
ments 70 the gentlemen assembled at ~
ton, aud hopn to be able to send them news
of the great international bnat race that
will be gratifying to both nations.'
" The usual rate of transmission Is about
ten or twelve words per minute. Lo king
for the mechanism by which these wo der
ful results were obtained. the inquiriDg visi-
tors observed, on their right pltced on a
marble pedestal, q medium sized spool Of
silk covered copper wire, said To consist OF
several thousln and turns or coavolutions, In
the middle OF which spool, suspended by
single silkwOrm f0re, was u minute mirror
attached TO a little magnet made from a
piece OF watch spring. From a lamp prop
,rly placed and shaded, beam Of light was
thrown upon this mirror, AMI from the mir
TOR was reflected, two hundred times enlar-
g-d, upon the gradu .ted screen in front Of
the mirror in foot Of the interpreter, the
flame like image already mentioned. 10
transmitting, from Duybury to Brest, the
operator, with his RIG BIT hand, makes use Of
wo keys or springs, ole of which, being
pressed, causes, al Brest, a d, Election In a
similar mirror, ling the image a ime to
the right, while, pressing the other key de.
fleets the mirror at Brest In the sppos TO d.
rection, sending the image TO the len. Its
indications are thus int-rpretef: q Jerk or
fitting once 20 tue left q Il then once
to the right dru ites the letter fitting
once TO the risnt atd then Ihrre times TO
the left, denotes the lrttrI b ; and thu, let
ter by leit. r, III words are p d.
"P stag into nv. adj lung - on, The deli
cate instrum n ) rNrf Tor trs ing the ,l'c
iric conductlOu Of the cable are shown
among which are coui u ers a I'd b,tteries
reLostats and shunts, bridges, switches, and
p'ugs, d growing Al, the wonderful astat-
ic grvanomater OF Sir William Thompson.
But possibly il would weary our rfapers ~
tell of ohms aid megohms, farads and meg
afarads, volts and microvOlts, aud al tho
| terminOlagy of combustion, resistance, cleo
| trOstat'c capacity, aud continued electrified
| tion. IL may, no Sever, crafty them to
learn that the insulation of The deep sea ca
BILE, between Brest -nl St. Pierre, has more
than doubled in efficacy during the short
month which has elapsed since this cal o
was first committed TO the embrace of tue
Cd 0cean-as is evinced by the fact that
soon after il was laid, the insulation resist
ance rose TO $500 megohms per nautical
mile. This Improvement In the insulation pi
the re 'p-sea cable Is believed to DO mainly
due to the GOODNESS or diminished tempera
ture to which II is subjected al great ocean
depths. T Q insulation resistance OF the
| portion Of the cable connecting Duxbury
and St. Pierre Is much less, namely, l50t
megOhns yer nautical mile.
"lf one would inquire OF a cable cleo
tritian-what Is a mig nm he might, with
piopri' ty, be told that is a million ohms
Should he still further inquire but what 1,
an ohm 7 suitable r'ply would be, II Is the
yardstick of the electrician by which he
measures the electric condition of conduc
tors aud which may be represented by !
round wire Of ppre copper one-twentieth.o i
AN inch In diameter aud 240 feet In length
It the temperature OF 60 degrees of IN,
Fahrenheit thermometer while m. ihn
by which he measu es the rssistsncs o.
insulator', is a unit the length Of which is 4
million mes as great"