1866.] THE MOUNTAINS AEOUND LAKE NYASSA. 85 



The gneiss is often striated, all the striae looking one way — 

 sometimes north and south, and at other times east and 

 west. These rocks look as if a stratified rock had been 

 nearly melted, and the strata fused together by the heat. 

 From these striated rocks have shot up great rounded 

 masses of granite or syenite, whose smooth sides and crowns 

 contain scarcely any trees, and are probably from 3000 to 

 4000 feet above the sea. The elevated plains among these 

 mountain masses show great patches of ferruginous conglo- 

 merate, which, when broken, look like yellow haematite with 

 madrepore holes in it : this has made the soil of a red 

 colour. 



On the watershed we have still the rounded granitic 

 hills jutting above the plains (if such they may be called) 

 which are all ups and downs, and furrowed with innumerable 

 running rills, the sources of the Eovuma and Loendi. The 

 highest rock observed with mica schist was at an altitude of 

 3440 feet. The same uneven country prevails as we proceed 

 from the watershed about forty miles down to the Lake, and 

 a great deal of quartz in small fragments renders travelling- 

 very difficult. Near the Lake, and along its eastern shore, 

 we have mica schist and gneiss foliated, with a great deal of 

 hornblende ; but the most remarkable feature of it is that the 

 rocks are all tilted on edge, or slightly inclined to the Lake. 

 The active agent in effecting this is not visible. It looks as 

 if a sudden rent had been made, so as to form the Lake, and 

 tilt all these rocks nearly over. On the east side of the 

 lower part of the Lake we have two ranges of mountains, 

 evidently granitic : the nearer one covered with small trees 

 and lower than the other; the other jagged and bare, or of 

 the granitic forms. But in all this country no fossil- yielding- 

 rock was visible except the grey sandstone referred to at the 

 beginning of this note. The rocks are chiefly the old crys- 

 talline forms. 



One fine straight tall tree in the hollows seemed a species 



