316 PROFESSOR SMITH’S JOURNAL. 
to Yallalla was therefore resolved upon, in order that, after 
having examined this cataract, we might take such further 
measures as should appear to be advisable. 
August 14. We set out to the number of about thirty, 
and passed across the river to a small sandy beach, termi- 
nated by sand hills, on which the hippopotami commonly 
dwell when on shore. A steep ascent led to a village. 
Having gained the platform, we found the declivity on the 
other side precipitous, but no trace of mica slate in the 
formation. - - - - - - - - The mountains here 
consist of compact feldspar, and resemble those at Nokki. 
On reaching the high land, the country assumed its usual 
appearance, which resembles very much that of old or- 
chards, composed of stunted Annonas, and three other sorts 
of trees. Having soon arter reached the hill on which the 
banza stands, and passed through the lofty palms and 
Adansonie in which the village is buried, a view of the river 
opened all at once upon us, and we discovered the cele- 
brated fall of Yallalla, at a distance of about a mile and a 
half. But how much were we disappointed in our expec- 
tations on seeing a pond of water only, with a small fall 
of a few hundred yards! We descended the steep barren 
hill, and arrived at the fail. ‘The rocks on both sides of 
the river were precipitous. ‘The mica slate is slightly un- 
dulating, and abounds with veins of quartz and compact 
feldspar. This formation of the rocks may possibly have 
very much weakened the force of the waters of the river. 
The inclination is half an angle (qu. 45°) in the same direc- 
tion as the course of the water and the declivities are oppo- 
