GENERAL OBSERVATIONS. 358 
try were mica-slate, quartz, and sienite ; but here the rock 
‘formation, though not entirely, was considerably changed ; 
the granite mountains and hills of pebbly quartz having 
given way to clay and ferruginous earth, and the mica-slate 
to lime-stone. ‘I'he banks of the Zaire are now no longer 
lined with continued masses of mica-slate, but many rocky 
promontories of marble jut ito the river, with fertile vales 
between them ; and the reaches of the river itself stretching 
out into broad expanded sheets of water, resembling so 
many mountain lakes. The greater part of the surface 
was now fit for cultivation, and towns or villages followed 
each other in constant succession, far beyond the limits of 
the Congo territory. Vegetation was more generally dif- 
fused, as well as more varied; and rills of clear water 
trickled down the sides of the hills, and joined the great 
river. It was just at the commencement of this improved 
appearance of the country, where, from the sickly state of 
the party, and the loss of their baggage, Captain 'Tuckey 
was reluctantly compelled to abandon the further prosecu- 
tion of the objects of the expedition; and in some respects 
it was fortunate he did, as had he proceeded two or three 
days longer, the whole party must unquestionably have 
perished in the interior of Africa, and might perhaps never 
more have been heard of. 
The account which the missionaries have given of the 
climate, corresponds exactly with that which was expe- 
rienced by Captain Tuckey. “ The winter,” says Carli, 
“‘ of the kmgdom of Congo, is the mild spring or autumn 
Zz 
