1! 



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 atNokki. 

 On reaching the high land, the country assumed its usual 

 appearance, which resembles very much that of old or- 

 chards, composed of stunted A nnonas, and three other sorts 

 of trees. Having soon after reached the hill on which the 

 banza stands, and passed through tiie lofty palms and 

 Adansoniae 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 fall. 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- 



