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way simultaneously. Thus, instead of one big vent, there will 

 be numerous scattered small ones, the flows from which will 

 coalesce into continuous sheets of lava. These may therefore 

 be better described as Plateau Eruptions rather than as Fissure 

 Eruptions. 



Cone Eruption. 



Fissure Eruption. 



Plateau Eruption. 



Fig. 8. — Three Types of Volcanic Eruptions. 



Rift Valley. — After leaving the Kapte plains we came 

 upon a second interesting type of structure. The valleys we 

 had previously seen were constructed on the same plan as those 

 of England ; for their courses were sinuous and their slopes 

 rounded, since they were made by the familiar processes of 

 denudation and erosion. But, on emerging from the Kikuyu 

 forests, we entered one which was straight in direction, and was 

 bounded by parallel and almost vertical sides ; its characteristic 

 features were that its lines were straight, and that its angles 

 retained some of their original sharpness, for the direct action 



