Vili INTRODUCTION. 
whose surface is very considerably higher than the sink of 
North Africa, through which the Niger is stated to flow. 
Secondly, because the Nile of Egypt, in this case, must 
necessarily be kept up at the highest pitch of its inunda- 
tion for a long time, after that of the Niger, which is well 
known to be contrary to the fact. Neither was it probable, 
that its waters were discharged into the sea on any part 
of the eastern coast, there being no river of magnitude on 
the whole extent of that coast from Cape Guadafui to Cape 
Corientes. The hypothesis therefore, of the dispersion and 
evaporation of the waters of the Niger, in lakes of an ex- 
extended surface, was the most plausible, and perhaps the 
more readily adopted, as it fell in with ancient opinion, 
The stream of this mysterious river being now traced 
with certainty from west to east as far as 'Tombuctoo, so 
little suspicion seems to have been entertained of the pro- 
bality of its making a circuitous course to the sea on the 
western coast, near to which it has its source, that the ex- 
amination of this side of Africa seems entirely to have 
been left out of the question. But when Park was pre- 
paring for his second expedition to explore the further 
course of this river, it was suggested, that the Congo or 
the Zaire, which flows into the southern Atlantic about the 
sixth degree of south latitude, might be the outlet of the 
Niger; and as this suggestion came from a person who, 
in the capacity of an African trader, had not only become 
wellacq uainted with the lower part of this river, but had 
actually madea survey of it, the idea was warmly espoused 
by Park, who, in a memoir addressed to Lord Camden, 
previous to his departure from England, assigns his reasons 
for becoming a convert to this hypothesis; and he adds, 
