Evening star. [volume] (Washington, D.C.) 1854-1972, 1906-04-07

four tides in every twenty -four hours
two high tides and two low tides. Rough
ly speaking, each tide lasts six hours;
that is, the ebb lasts about six hours,
then the tide turns flood for six hours,
and so on. But there are localities where
tho tides run only twice day of twenty
four hours; and there are other spots
where there is no perceptible high or low
water at all.
The most notable of the latter Is Bats
ham. in Tonquin. At this point two great
tide waves meet with forces that are ex-
actly opposite and SO nearly equal that
the water does not rise or fall percept-
lilly.
Compare with this the great Bay OF Fun
day where there are tides that have been
Known to rise 10 feeti
1t is in places where the ocean rises to
great heights like this that the tides make
the most wonderful of ocean wonders-the
tidal bores. These tidal bores are simply
enormous masses of water that rush from
the open sea when the tide turns from ebb
TO food. and pour In incredible volume to
fill the coastal basins, bays or rivers that
have been emptied by the outgoing tide.
With the whole weight of the open ocean
behind them they sweep into the narrow
inlets with exactly the same violence with
which a big pump drives masses OF water
through small hose.
Moncton's Tidal Bore.
The Bay of Funday, having about as great
a range OF tides as any place in the world
causes the most regular tidal bore known.
1t is not as awesome In its manifestation as
the bore of the Tsien-tang near Shanghai,
which is known as the Great White Thing
of Hang-Chau, and has the honor OF hay
ing temples and priests maintained to pacify
1t, but the Great White Thing comes only
at long. though absolutely regular inter-
walls, while the famous bore of the Petitco-
diac river the Bay of Funday comes
every day with the regularity OF the tide
itself.
The Petitcodiac river is in New Bruins
wick, and the finest spectacle is when the
bore reaches Moncton. For nine, and even
nine and one-half hours before the arrival
OF the bore the river GIBBS steadily seward
until in many places its bed Is almost dry
and there is only trickle OF water in parts
OF il.
BY the time this surprisingly long ebb
has run itself out at Moncton and the water
Is at It's lowest stage there 1t Is half tide at
the entrance to the river, more than twenty
miles away-that is, while the river bed at
MonctOn is almost dry the water is standing
twenty-one feet high at the mouth of the
river. But the river bed at Moncton is
twelve feet above the lowwater level at the
mouth of the river Hence at half tide the
river at the entrance is standing nine feet
higher than the low water level at Moncton.
In other words. at every half tide Moncton
becomes a high tidal sink lying nine feet
below the level of the water in the Bay of
Funday.
Now all this enormous mass of water is
pressing with all its might to get into the
narrow funnel of the river The sea con
tinues to rise steadily. Suddenly 1t bursts
over the bar and the great bore begins.
( For an hour every day before it's first
visible Sign reaches Moncton. the noise
of It's splendid coming is heard. Like the
roaring of mad surf it beats through the
town. There are wrath and menace in X
and the stranger who does not know of the
bore might well IMAGINE that the sea had
broken its bonds and was corning ashore
to sweep the solid land.
The actual bore begins eleven miles above
the entrance of the river at place called
Stony Creek. The incoming food travels
those eleven miles In two hours-a most re-
markable rate of speed for water to move,
for Notwithstanding the many loose state
ments about the veiocities OF currents, the
average tidal current does not run more
than two miles an hour, and three-miie
current Is swift one indeed
But at Stony Creek the river becomes
contracted and the speed of the bore then
eight and half miles to Moncton in one
hour.
A White Wall Of Sea.
1t comes not a wave but as a solid
white wall. that speeds so swiftly that II
actually rolls along and over the river as
II the brown stream were solid floor It's
angry front, rising sheer above the river
three and sometimes even five feet high.
extends straight from bank to bank. 1t is
the front of an inclined plane whose higher
end Is toward the sea; SO that this bore
looks like sloping hill of water moving
Inland by some weird agency
When that enormous tide has run its full
the river is twenty-ons feet deep at Mono
ton. SO fast does il rise that a record has
been made OF rise of nine feet in seven
teen minutes: Al the entrance of the
Petitcodiac into the Bay Of Funday the ac-
tual rise Is forty-two feet above low water
level.
Another strange freak OF the tides Is at
st. John, New Brunswick, where each tidal
change makes a waterfall In the river that
Is smooth and calm at all other times At
the time of ebb this waterfall falls down
the river At the time of flood, the water
fall pours up the river and thus actually
tumbles up hill. The freak Is due to a
rocky ledge that runs across the river and
retards the tidal flow both ways till there
is vast head" OF water behind the cur
rent and at last enough accuInulafes tn
burst over the ledge. 1t is a strange Spec
tacle that one never wearies of Watching
Another final tidal bore Is the one in The
Hoogiy branch OF the Ganges river 1t
travels seventy miles In four hours ana
sometimes appears suddenly as Ilnuid
wall five feet high. The Brahmaputra and
the Indus also have bores, as have the
Seine, Severn, SOiWay and other rivers of
Europe; but they are small affairs compar
ativeiy, although the tidal currents of some
OF the Scotch ffrths are such as to defy full
powered steamships when great winds helm
thSm TO swirl their fastest.
The Great White Thing.
However thcg n sink into insignifcance
before the bore OF the Tsientang-the Great
White Thing of Hang Chau, the mightiest
bore in the world II comes as an nm.
broken mass of water one mile wide. Cant
Moore. studying Its passing at HaiRing, es-
Inmates that one and three-quarter million
tons OF water passed IN ons minute.
The Great white Thing comes on the