STRENGTH OF CURRENT. 
373 
only — requiring such an arrangement to enable it to 
receive the immense volume of water brought down 
during the rainy season. 
It has been a subject of discussion, which is the prin- 
cipal outlet of the Niger, We can only reason upon 
our few facts ; but it may be presumed that the greater 
the angle at which a divergent leaves the parent stream, 
the less likely is it to be the principal branch ; as the 
current being necessarily more sluggish, obstructs its 
own passage by a greater deposit of alluvium. We found, 
in fact, such to be the case with the extreme divergents 
right and left ; whereas the central, or Nun branch, pre- 
serves the main direction of \he river, bisecting the 
Delta, and carrying the alluvial deposit farthest out into 
the sea, forming the salient point called Cape Formoso. 
These important attributes, we contend, are sufficient 
to entitle the Nun branch to be considered as the princi- 
pal outlet of the mighty Niger ; although the only access 
to it from the estuary is by a shallow channel, not more 
than fifty yards wide. 
The current increased in strength as we ascended the 
river, being about two miles per hour at the lower part 
of the Delta, and three miles and a half at the con- 
fluence, while in a narrow part, abreast of Bari’aga, it 
ran four miles. These averages were, however, taken 
during an interval of twenty days, while the river was 
rising and increasing in volume. In the dry season, the 
current is very much less ; in some places, where the 
stream is broad, it was not more than half a knot. The 
ditferenco between marks made at Iddah in the be- 
