There was no longer the vast
sandy desert with the river flowing through its sterile course on
a level with the surface of the country, but after traversing an
apparently perfect flat of forty-five miles of rich alluvial
soil, we had suddenly arrived upon the edge of a deep valley,
between five and six miles wide, at the bottom of which, about
200 feet below the general level of the country, flowed the river
Atbara. On the opposite side of the valley, the same vast table
lands continued to the western horizon.
We commenced the descent towards the river; the valley was a
succession of gullies and ravines, of landslips and watercourses;
the entire hollow, of miles in width, had evidently been the work
of the river. How many ages had the rains and the stream been at
work to scoop out from the flat table land this deep and broad
valley? Here was the giant labourer that had shovelled the rich
loam upon the delta of Lower Egypt! Upon these vast flats of
fertile soil there can be no drainage except through soakage. The
deep valley is therefore the receptacle not only for the water
that oozes from its sides, but subterranean channels, bursting as
land-springs from all parts of the walls of the valley, wash down
the more soluble portions of earth, and continually waste away
the soil.
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