2 E. H. L. SCHWARZ 
runs south and ends in a cul-de-sac surrounded by bare faces of 
dolerite; the other runs west. The bottom of the valley rises very 
gently and is about a hundred yards wide. It is surrounded every- 
where by the dolerite; the new railway skirts the edge of the 
southern branch, and the view as one looks down into this cleft 
from the carriage window is most remarkable. The streams 
flowing down into the Kei from the escarpment of the plateau are 
very steeply graded, but here is a valley which begins at the head 
with a vertical wall 1,000 feet deep. 
The laccolite is about three miles long from east to west, the ex- 
posed vertical side facing north, but there is a low-lying expansion 
of about 100 feet above the level of the river which is exposed in a 
cutting near the zig-zag of the railway, and this would add another 
mile to the length along the river. The faces of the main mass are 
quite vertical toward the river which comes almost due south to 
the laccolite, abuts against it, and follows its northern edge to the 
east. The sedimentary rocks are for the most part cleared away 
from the northern side. On the downstream end, above the hotel 
and road-bridge, the dolerite has been exposed for a long while and 
there is only a steep slope rising at an angle of 30°, studded with 
gigantic bowlders of dolerite, but for the rest grassy, with sparse 
mimosa trees. About two miles up the river is the Etanga Valley. 
On the west the dolerite rises in a magnificent vertical wall, capped 
with horizontal beds of sandstone for some 30 feet. On the outside 
of the vertical face there is a zone of much-jointed dolerite rising 
in pinnacles on either side of a sort of window of sedimentary rocks 
through which the vertical face appears. The pinnacles are the 
jointed outer margin of the laccolite. The dolerite to the west 
of this plunges into the sedimentary beds which form the walls of 
the valley of the Great Kei River lying almost at right angles to the 
northern face of the laccolite. In other words, the laccolite has 
barred the way of the river which flows at its foot, and the weathering 
that has allowed a small amount of sedimentary beds to remain 
plastered, as it were, on to the face of the laccolite on the west, has 
cleared all these away down stream on the east. In the same way 
the sedimentary beds form half the height of the hill on the west 
of the Etanga Valley, between the dolerite and the river, so that 
