The Mount Holly news. [volume] (Mount Holly, Burlington Co., N.J.) 1891-1942, 1912-02-20
FORCE OF THE SEA
Terrific Power Is Generated When
a Cyclone RACES.
THEN THE WATERS RUN WILD
All Regularity Of Wave Motion Ceases
as the Sea Bursts Its Bcunds-Gran-
lite Blocks Weighing Thousand Tons
Tossed About Like Pebbles.

40 Aue SSa 0dtoto iSo 0V6b0~ ->1TAU'
lite Blocks Weighing a Thousand Ton,
Tossed About Like Pebbles.
A pond troubled by a pebble gives q
comprehensive idea of the mechanism
Of the perpetual motion Of We ocean
now slow. regular and majestic, run
ming from horizon to horizon, now
rushing In ungovernable fury against
the land. When a pebble falls in q
pond it produces a fine circular line
which widens, multiplying until stop
ped by its boundaries. Just SO is pro
duced the surging of the sea.
To judge from appearances. the
swells transport the water toward the
circumference of the pond In point OF
fact they do nothing Of the kind, as il
easily proved by match or splinter
Of wood being cast upon the water
The match is hardly raised or lowered
by the passage Of the swell The actor
in evidence is simply the transmission
of motion. not the transmission OF
matter.
The fine waves of the sea are gen
Grated by the wind as fine waves are
generated by the wind when 1t ripples
a field of grain ready for the harvest
The waves that run over the field OF
grain are real waves, often waves in
fierce action. The spears Of grain are
immovably fixed to the ground by theil
roots, but every blade transmits its os
cillatory movement to the next blade
just so liquid molecules are formed.
In the middle Of vast ocean, such
as the equatorial Atlantic, for instance
great regular fluctuations are seen null
tiplying In parallels like the burrows
In vast plowed field. On the broad
ocean the liquid mounds of the sea rise
with every swing with more or less
even regularity.
The mariners imagination has given
the great waves of the high sea the
reputation of fabulous height. Relia-
BILE authors have talked of waves
mountain high and of waves 120 feet
in height. Exact measurement has Civ
en- closer estimate.
The waves of the high sea, of the ma.
jor oceans. attain the height Of fifty
feet under the exceptional conditions
Of tempest In the vicinity of Cape
Horn and the Cape of Good Hope
The surges here estimated are those in
free circulation on the high seas.
When wave, whatever its strength
or its weakness, meets a solid obstacle
whether that obstacle be rocky cliff
or ship, the swell rebounds to ex-
traordinary heights. Lighthouses are
often swept by the sea from base to
summit.
The length of waves is between
twenty and thirty times their height
and the slope of the seas hills is very
gentle. A wave sixty feet high is
somewhere between 1000 and 1.2OC
feet long.
At the axis of the revolving tempest
called a cyclone there are many wave
systems, moving in all directions
meeting and combining. When the cy-
clone is in action the sea is said to
burst its bounds"
At such time all regularity of wave
succession ceases. and the sea runs
wild, with force beyond human power
to estimate. Blocks of granite weigh
ing from 1000 to 200 tons are caught
by the sea and rolled like pebbles to
distances Of 800 feet and more, and
sea walls are splintered as by hatch
cts. The live power" of a furious
sea is estimated by multiplying the
mass Of the surge by the square of its
speed.
When the surf, impelled by the drive
Of the broad sea, meets a solid obsta-
Gle its pressure is thirty tons per
square meter of water. This estimate.
which is close, explains how water,
when continually sapping the foot of
a cliff, breaks down the land, forces
back the shore line and little by little,
constantly and surely, increases the
seas domain.
A wave from 33 to So feet high and
625 feet long-such wave as the sea
produces every eighteen seconds-rep-
resents power of about 1850 horse
power, steam, per square yard.-Har-
per's Weekly.