GRAPHIC DESCRIPTION OF AFRICA. 
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districts the rivers have to find their way across open lowlands 
where the volume of water soon diminishes, and is lost in the 
parched earth, the country here is like a well-filled sponge. The 
result of this abundant moisture is that the valleys and fissures of 
the earth through which the water flows, whether in the form of 
little brooks and streamlets, or of great rivers, are clothed with all 
the majesty of a tropical forest; while an open park-like glade, the 
chief feature of which appears at the first glance to be the amazing 
size of its foliage, fills up the higher-lying spaces between the water¬ 
courses and the galleries. 
The number of distinct types of trees, and the variety of forms 
among the undergrowth, is very great. Trees with large trunks, 
whose height throws into the shade all the previously seen specimens 
of the Nile flora, not excluding the palms of Egypt, are here found 
in serried ranks, without a break, and beneath their shelter the less 
imposing platforms are arranged in terraces. 
LEAFY CORRIDORS WITHIN VIRGIN FORESTS. 
In the interior of these virgin forests, leafy corridors, rivalling 
the temple walls of Egypt, lie veiled in deep perpetual shadow, and 
are spanned by a triple roof of foliage, rising vault above vault. 
Seen from without, the galleries appear like an impenetrable wall 
of the densest leafage, while from within corridors of foliage open 
out in every direction beneath the columns of the tree stems, and 
are filled with the murmuring voice of springs and water-courses. 
The average height of the roof of leaves measures from 
seventy-five to ninety feet; but very often these galleries, seen from 
without, by no means produce the imposing effect which is felt from 
within in looking up from the depth of the valley or the water-side; 
because in many places the depression of land or water which makes 
up the gallery or tunnel-like character of the scene scarcely allows 
half of the forest to rise above the level ground, many galleries 
being entirely sunk in the depression. Great tree trunks, thickly 
overgrown with wild pepper, rise from the depths, and support wide- 
spreading branches draped with lichens and mosses, above which 
towers the remarkably fine tree called the elephant’s ear, which 
