Evening star. [volume] (Washington, D.C.) 1854-1972, 1900-07-28
wire, but best Of all Is to choose q route
as free from such enemies as Is practicable.
Selecting n Suitable Route.

wire. but best of all is to choose q route
as Tree from such enemies as is practicable.
Selecting n Suitable Route.
Finding the best route is the most diff
cult thing connected with submarine teleg-
raphy. though few outside Of scientific cir
cles ever think of IL The surface of the
earth beneath the oceans is as irregular rs
it is elsewhere. and a cable can no more be
laid at random on the sea floor than can a
line of rails be laid haphazard on land. In
either case suitable bed is necessary. hut
II is obtained in very different manner The
ped OF a railway Is made. IL mountains lie
in the way they are tunneled or cut
through; streams are bridged and valleys
crossed by embankments but cable engi-
neers can do nothing of the sort for hui
man skill is useless in the deep waters.
A bed must be found ready made and the
only means of finding 1t is the sounding
rod.
The rod in use in the United States was
invented by Capt. G. ID. Sigsbee of the ILL
fated Maine. and is an improved form of
the one contrived by Professor J. NJ
Brooke. now of the Virginia Military In
sutute. emitting details. it consists of
cylinder arranged to sink into the mud and
retain specimen of the bottom. 1t is
weighted by a shot that is automatically
released when the bottom is reached, thus
relieving the line and lessening the danger
of losing the rod. The line is Of piano
wire, and is coiled on reel that registers
the revolutions made in paying out. and so
gives the depth. Besides the rod. the line
carries A cup also an invention of Cant
Sigsbee, that collects sample of the water
near the bottom. and a peculiar form of
thermometer that is not affected by the
pressure of the water. With this equip
nent. each sounding gives the depth Of the
water. the temperature and composition of
Its lower strata and the character of the
bottom, and from these data the cable sur
Feyor deduces the knowledge he requires.
Work of the Surveying Ship.
When new cable is projected a survey
ing ship is fitted with sounding appliances
and sails slowly over the proposed route.
Soundings made as often as is de-
manded by the character of the sea floor,
and if this be fairly level and uniform the
intervals are made longer than IL II be
rough and uneven. The depths are record
ed and compared, and from them a profile
Is prepared that shows the different levels
of the bottom and its hills and valleys
steep slope is dangerous-as the tendency
to slip down puts a severe strain the
cable that may break 1t. For the same
reason a narrow ravine is to be avoided as
its edges may chafe and destroy the insu-
lation even if the whole cable is not cut
through-and there is no means OF over
coming these obstacles except by avoiding
them. Very deep water is Objectionable,
because 1t is difficult to lay the cable in II
and still more so to grapple and raise II IL
1t should need repairs.
From the Bottom of the Ocean.
The material brought up from the bottom
is Of great value as indicating the state of
the water and sea floor. Over a large part
Of the ocean the bottom is covered with a
light powdery mass called ooze.
1t is made of the shells or tests Of little
animals that can hardly be seen without
microscope, that have died and settled to
the bottom snowflakes settle through
the atmosphere to the earth. This Is the
sort of deposit that made our beds OF lime
stone ages ago. and ii is the best kind OF
resting place for cable, for Ii sinks into
the soft, fluffy mass and is protected from
harm. Ooze shows still water. for a cur
rent would wash it away as a wind blows
snowfiakes. and if the floor sloped steeply
the ooze would slip down like sand on
roof, so when the rod shows ooze II indi-
Gates calm. still water and a nearly level
floor. A hard bottom of gravel rock or
clay shows current that should be avoid
ed If possible. Near shore the refuse from
the land may heap up into piles Of rotting
matters that may be injurious, and some
kinds of sea weeds are said to have done
damage, perhaps by the Iodine they contain.
Detecting Obstacles.
Submarine volcanoes would destroy q
cable very promptly. and they should be
detected in advance il possible. The Their
mometer aids in this search, as a sudden
rise in temperature is suggestive. but the
rod is apt to bring up bits of volcanic ash
or lava that will be conclusive.
II any great obstacle is found another
route must be tried. and these trials must
be continued till a practicable one be found
"a task that may take years, but when II
is finally discovered a great step in the
advancement of the word is made. The
steamer Albatross of the United States fish
commission has been engaged in the Pacific
for several years in making soundings and
determining other facts that may be OF
importance in case the proposed Pacific
cable materalizes. In 1891 a survey was
authorized between the United States and
the Hawaiian Islands. which made by
Lieutenant Commander Clover. comma ndins
the steamship Thetis. the Albatross being
needed in Alaska before the work was
done. 1t is hoped that the latest cruise OF
this noted vessel will clear the way for
the last long cable that yet remains TO be
laid