The Washington weekly post. (Washington, D.C.) 1878-1916, 1900-02-13
MESSAGES UNDER WATER.
| some of the Difficulties 10 he Overcome in
Laying the Pacific Cable.

From scribnsrs Magazine
In view Of the constant activity in At
lantic cables which has resulted in a new
cable about every two years since the
first successful cable OF 1850. il stands to
reason that the difficulties offered by .he
Pacific Ocean must be very great for the
nineteenth century 10 reach its close with
Qua definite scheme for spanning the Pa
csic by telegraph having been adopted.
The difficulties may be summed up in a
few words: First. the great cost OF 4
complete system Of cables. second. the eX-
IRENE depth OF water known TO exist in
certain parts of the Pacific and feared in
others; third, the long distances between
landing points; and, fourth. the lack of
intermediate points having an active trade.
The estimated cost Of the British Pacific
cable, for a single cable connecting Van
couyer with Australia and New Zealand,
is placed at about &010 600. including two
repairing ships and a sum OF $4,000 for
maintenance of the cables for six months.
The president of one of the cable com
panieS OF New York estimates the total
capital cost Of cable to Japan, Austria
liza, and the Philippines via Hawaii al
Sl2,0J,oOo and the cost of maintenance in
Guiding two repairing ships and of operat-
ing expenses, at 100000 a year II is not
considered that a single caOie Will he suf-
hclent 10 insure permanent CommuniCa-
uOh, ana any scheme for Pacific cable
must provide eventually for duplicate
cables throughout the entire route. so that
the total capital cost Of a thoroughly re-
llao!e and efficient Pacific cable system
may be put down at approximately $6.Ug0-
900, which would include two repairing
shlpS, a reasonable quantity of spare cable,
ana the equipment of operating stations
at the various landing points.
One of the essential features of n sub
marine cable is the speed of signaling.
In operating long cables very delicate in
struments are required, AID the currents
arriving - the receiving end are very
feeble in comparison with those employed
IN land-line signaling. The longer the
cable, naturally. the feebier the impulses
arriving at the receiving END. a short
cable, cable of under 1000 miles being
generally considered a short cable. gives
speed or signaling amply sufficient for
all purposes, with 4 conductor weighing
about 100 pounds TO the mile, surrounded
by an insulating envelope of gutta Urrcha
weighing about an equal amount. When
we come 70 cable OF about twice this
length it is found Necessary, in order %
get practically unlimited speed, that is.
speed as high as the most expert Op-
orator can read At, TO employ core OF
600 pounds of copper 10 the mile, insu-
ldteu WIN fV POUNDS OF SutLd DTrCld IN
the mile. These are the proportions Of
copper and gutta percha in the 1891 Anglo
American Atlantic cable, which is CON
sideTed the record Atlantic cable for SDeed
of working, and mas been worked. ty au-
tomato transmission. at the rate OF some
s. words a minute. The type Of cable pro-
posed for the Vancouver Tanning section
Of the British Pacific cable, a. designed
by Lord Kelvin Is TO have core ii so
pounds of copper and 800 pounds Of gutta
percha TO the mile. and Is calculated to
give a speed of twelve words per minute
over a length Of 1860 miles. IL is not CON
SideTed safe to adopt a very much heavier
core than this, for tne reason that The
weight OF the complete cable with a core
that should weigh more than aoout half
a ton to the nautical mile would be 50
great that picking it mp for repairs from a
depth of 5000 fathomS would he an eX-
tremely difficult and hazardous operation.
The establishment of Geographic com
municatiOn results in new ways Of doing
business and opens up new avenues OF
profitable endeaVOr. The electric current
like that set alive by royalty or by the
President at the opening of an exhibition.
sets in motion a variety Of machinery
that before lay dormant. The trade OF
the Pacific is looking up, and hosts of en-
! terprsing Americans are bUsily engaged
! in looking up that trade. 4 trans Pacific
cable is not an absolute necesSity be-
i've and relatively slow, between America
ard the far East, Is already had over the
existing system; but that such a Cabl1
would soon find a profitable traffic is not
10 be questioned by those who are at all
familiar with the rising volume Of trade
between the far East and America. And
be It remembered that to-day every com
merCial transaction between two points
separated by the sea- like this article,
begins and ends with a cable.