374 
HILLS AND MOUNTAINS, 
ginning of September, 1841, and in the following July, 
shewed a fall of the river of thirty feet. But these can- 
not be taken as the highest and the lowest periods. The 
wind generally blows up the river, or from the south- 
west, especially during the Spring months. The weather 
is then delightfully cool. 
Above the mangrove swamps, the land gradually 
emerges, with vegetation increasing in richness, to the 
vertex of the Delta, where diluvial formation is first seen 
in gentle hills, backed at Iddah — two hundred and twenty 
miles — by greater elevations ; these terminate in abrupt 
cliffs of sandstone, one hundred and fifty feet high, on 
the left bank of the river. Above this are many isolated 
mountains, of irregular forms, until we reach the con- 
fluence of the Chadda with the Niger, about two hundred 
and seventy miles from the sea, where there is greater 
continuity and height in the range, which, under the 
vague name of Kong Mountains, were formerly supposed 
to be the barrier which opposed the course of the Niger 
to the Atlantic. 
From this part commences the series of table eleva- 
tions, isolated in some parts, stretching up both sides 
of the Niger as far as Rabbah, about four hundred and 
thirty-three miles from the sea, on the left bank ■ on 
the right they are not seen so far. At this city some 
undulating hills terminate in cliffs, similar to those at 
Iddah. 
All the lower parts of the river are covered with dense 
forests, except where partially cleared by the hand of 
man ■ but above the confluence, there is a great deal of 
