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

get into "knka" Its weight is only one ton to the
mile and Il Il contracted to bear three TOMS thou&n
its breaking strain will be over four The specs9c
only 81 about th hsss IT sd dc dosn rs
weigh: will be reduced by the displacement OF tne
water by about onethrd. But in spite OF this pass
ing over the deepest places the cable VIII De tired
length Of cable TINT S would sacs s1 reach The bot
tom must always be cut. allowing for the slope, ana
the weight Of five miles of it, even reduced BY one
third, VIII be severe test OF its strength. Unui
bic to gel an electric current to circulate in .
wire beyond Q certain length, and this alone
was considered fatal objection to transatlantic
telegraph: Lately, however, the discoveries Of
that beyond certain point the resistance offered by
wires to the electric current increase In very slow
ratio, as compared with the increase Of the length.
This, OF course, puts an end to the theoretical diff
Guilty but the practical fact yet remains that it has
never been attempted to pass electric currents
through wire more than about 1900 miles long
II the wire be in good metallic connection through
out its whole Length have M no fear an ads
verse the whole cable freely enough. There is ano.
Their phenomef on which will undoubtedly operate
very much against the efficacy Of the telegraph. 1t
When current is passing through wire Of consi
derable Length, and the connection be suddenly
broken. current ten times more powerful than the
one originally passing flows in the opposite direction
NJ IDO mOueut Ot tuo b0p8L6tOus ttkOco
the induced current. A wire few hundred
feet in length will communicate very
powerful shock in this way, even when very weak
battery is used. And when it is considered that
the power of the shock increases in direct pro-
portion to the length Of the wire and the rength
Of the current, some idea may be formed Of
what the induced current from the Atlantic cable
will be. 1t will certainly prove great obstruction
to the transmission Of messages and serious incon-
venience to those employed in the neighborhood Of
the machines. The company propose to use Morses
recording telegraph, and few dozen Of Smees
cells to work them with. These are undoubtedly
the most ecacious that can be used, and the least
liable to error of any. The vast quantity Of mate
Iials employed in the construction of this gigantic
cable would astonish those who are unacquainted
with the magnitude of the undertaking. The amount
of five strand .wine employed in covering the gutta
perchaed wire will be about 10000 miles, or suffi-
cient to 60 once and half round the globe. The
copper wire employed for the conductor will be
about 20 900 miles, white the thin Iron wire used
the external covering would 90 about seventeen
tines round the world, or very nearly to the moon
and back, being between 400 900 and 500 900 miles
long. If the scheme is successful 1t will be one of
the greatest engineering triumphs of the age, and
we may shortly after expect to see the globe, il
were, traversed in all directions by conveying
intelligence unseen and instaneousy to its most re-
mote parts.