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One of the
Natural Wonders of the World-
the Victoria Falls
Part 2 in a Series by Cecil
Keen
In its upper reaches, the infant
Zambezi gives no hint of the dramatics downstream. Its source, in a lonely
grove of trees on the watershed between Zambia and the Democratic Republic
of Congo (formerly Zaire), is joined by many tributary streams which grow
the river to become one of Africa's largest. For 750 miles (1200 km) the
river flows rather lazily over the surface of a vast sheet of lava which
forms the plateau of Central Africa. The Aluyi tribespeople who live along
this stretch of the river know it as the Lwambayi ('great river') and
each flood season they move to the higher-lying verges.
In the season of floods
March, April, May and June the river swells greatly in size but
the shallow valley contains it and the movement of the water is still
slow. Only a few minor rapids high up the valley, and the small Gonye
Falls, give it a flurry of speed.
| Suddenly the river experiences
a great change. It reaches a series of cracks in the sheet of lava
which lies directly across the course of the river, so placed that
it seems as though nature decided to play a prank on the lazy river
giant. The lava sheet is about 1000 ft (300 m) thick. The cracks in
it are narrow and filled with soft earth and broken rock. The river,
leisurely scouring out its course, found the lowest (most south-easterly)
of the cracks and began carrying away the soft filling. The effect
of this was the excavation of a deep trench cutting across the flow
of the river.
Into this trench tumbled
the water, and immediately had to find a way out again. For a time
there was a chaotic rising and falling of water. Then, on the lower
edge of the trench, the river found a weak spot. This could have
been the dislodgement of a single boulder. The river flow was then
concentrated at this point, for it offered the easiest escape route
from the trench. The weak spot was steadily lowered and widened
until a remarkable waterfall had been created.
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The
above photo looks down
the series of gorges with the youngest,
the present Victoria Falls nearest,
and the oldest of 8 falls furthest away.
The Victoria Falls bridge
spans the 2nd gorge.
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The
Victoria Falls at low water –
an opportunity to see into the gorge and its rocky base.
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Along the full width of
its course the river tumbled into a deep trench only about 650 ft.
(200 m) wide. At the bottom of this trench the water rushed about
in wild disorder and then shouldered its way out of the trench through
the narrow gorge which formed from the original weak spot. At the
entrance to the gorge a surging mass of water was caught in a series
of whirlpools resembling a boiling pot.
After a time the river
found another weak spot in the upper edge of the trench. This weak
spot also grew to become a gorge through which the river forced
its way, abandoning the fall over the remaining upper edge of the
trench.
At this stage in its
development, the spectacle had changed. The river now poured into
the trench through one deep gorge, raced along the bottom of the
trench and then out through the gap in the lower side.
So far, this remarkable
series of erosions has been repeated in eight successive parallel
cracks. Each crack went through a similar process of transformation
in a series of vast erosions spread over the last 500,000 years.
The present crack is just past the most spectacular stage of its
development. Most of the river flow still falls over the full width
of the crack, but a weak spot is already being deepened on the western
end. This is the Devil's Cataract.
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Eventually the present waterfall
will disappear and the river will flow into the trench through this deepening
gorge. At least two more faults lie across the course of the river, immediately
above the present fall, and there are possibly even more concealed further
up the course.
| The Lozi (Barotse) tribespeople
living along the upper reaches of the river named the waterfall Mosi
o Tunya ('the smoke that thunders'). The Matabele called it Manza
Thunqayo ('water that rises like smoke'). When David Livingstone became
the first-known European to see the falls on November 16, 1855, he
named them the Victoria Falls, in honor of Queen Victoria.
Livingstone reached the
falls by canoe, paddling down the Zambezi River. He first saw the
clouds of thundering spray from about 6 miles (10 km) upstream.
Immediately above the falls he changed into a lighter canoe and
was paddled to the island that seems to be on the verge of toppling
into the thrashing waters below. From this island, Kazeruka (or
Livingstone Island), he peered down into the spray and got his first
glimpse of the magnitude of the falls.
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The
‘smoke that thunders' –
the great columns of spray
rising from the Victoria Falls.
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The
rainbow is present during all sunny
hours, and at times of bright moonlight.
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His guides told him that
at three spots near the falls the tribal chiefs offered sacrifices
to ancestors. These spots are within sight of a rainbow usually arching
the spray, which to the Lozi marked the presence of God.
When Livingstone re-visited
the falls the next day he planted peach, apricot and coffee seeds
and carved his name on a tree.
'This was the only instance
in which I indulged in this weakness', he later told William Baldwin,
the second European to see the falls. The two met during Livingstone's
third visit to the falls. The Victoria Falls are 5,570 ft. (1,700
m) wide and 328 ft. (100 m) high. They are one-and-a-half times
as wide and twice as high as the Niagara Falls.
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| The Victoria Falls are
divided into the Devil's Cataract (27 m. wide and 60 m. high); the
Main Falls, which in turn are divided by a projecting rock (524 m.
and 297 m. wide and 83 m. high); the Rainbow Falls (550 m. wide and
100 m. high); and the Eastern Cataract (304 m. wide and 96 m. high).
In April, after several
months of rain, the falls reach peak volume. The columns of spray
sent up by the crashing water have at times been seen 50 miles (80
km.) away. August to November are the driest months, and the best
for photographing the falls because of the relative absence of mist.
In particularly dry seasons the falls have been reduced to mere
trickles, the bulk of the water tumbling through Devil's Cataract.
During this time the other falls are little more than silver ribbons
falling down the dry black basalt rock.
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The
Zambezi River tumbling into its gorge. The Devil's Cataract is
closest in the picture. The white rapids going off at a 45°
angle show the location of a developing crack that will one day
become the new falls.
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David
Livingstone
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The edge of the falls
is reached through the cool, moist tunnels of the rain Forest. Always
shrouded in fine spray, the forest is a fairyland of exotic plants
thriving in the humidity. Concrete and gravel paths the only
obvious man-made intrusions since Livingstone's day have been
laid to stop sightseers trampling away the lip of the gorge. Parts
of the precipice opposite the falls have been cleared of undergrowth
to give a clear view, but the falls can also be seen from the depths
of the forest through glistening, dripping, spray-soaked leaves.
Early morning is a magic
time to see the falls. As the sun rises it tints the plumes of spray
pink and gold. There is a statue of David Livingstone (sculptured
by Sir William Reid-Dick) on the western end (Zimbabwe side) of
the chasm, overlooking the Devil's Cataract somewhat in a
state of needing repair in recent years.
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One of the dreams of Cecil
Rhodes was to span the gorge at the Victoria Falls with a railway bridge
although there were much easier and cheaper places to bridge the
river upstream. His bridge, completed in 1905, was designed by Sir Ralph
Freeman, who used the same type of construction as he did on the bridge
across Sydney Harbor, in Australia. The bridge was built in two sections
from each bank. The first attempt to join the sections failed because
the metal had expanded in the day's heat. The engineers waited patiently
to allow the sections to shrink during the night. It was at 6 am on April
1, 1905 that the gap between the two spans was finally closed before an
audience of Lozi tribesmen. They had been certain the bridge would fall
into the gorge, but to their astonishment the impossible had happened,
and a train engine with two trucks chugged confidently across the track.
Part
1: The Zambezi – Central Africa's River of Life
Part
3: The Zambezi – Reservoirs of Water: Dams on the River
To learn more
about the Zambezi River, click
here!
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