CONTENTS. 



the Shiri Highlands — Nature of the south Nyassa region — Changes in the 

 geological character of this region in the latitude of Mount Waller — Extent 

 of the Mount Waller sandstones — Relation of these deposits to the other 

 African sediments — Later deposits above them — Drummond's beds — African 

 lake pleistocenes — Arrangement of these different deposits — Extent of Drum- 

 mond's beds — Vast extent of the old African sandstones — Demonstration of 

 the existence of a great depression in the region of the lakes before the forma- 

 tion of the Great Central Range — The broad features of the past history of 

 these regions ............ 54 



CHAPTER V. 



THE GEOLOGICAL TOPOGRAPHY OF THE REGION NORTH OF 

 TANGANYIKA TO THE ALBERT NYANZA. 



Want of knowledge of the districts north of Tanganyika — Importance of these 

 districts in the consideration of the Tanganyika problem — Wide geographical 

 effects produced by the recent formation of the Mfumbiro Mountains — 

 Character of the country north of Tanganyika to Kivu — Former short exten- 

 sion of Tanganyika north — Absence of any former connection of Tanganyika 

 with Kivu — Characters of the Rusisi channel — Characters of the Kivu basin — 

 Peculiarity of the Kivu water — The north shore of Kivu and the Mfumbiro 

 Mountains — The volcanoes form a dam across the lake valley — Character of 

 these mountains — The valley of Kivu continued beyond them northwards — 

 The fauna of Lake Kivu is totally different from that of Tanganyika, but 

 similar to that of the Albert Edward Nyanza — Former connection of Kivu and 

 the Albert Edward — The volcanoes have resulted in the outflow of the Kivu 

 being turned intoTanganyika and a corresponding shrinking of the waters of 

 the Nile — The effect of this on the districts north of Kivu — The effect of this 

 on the districts south of Kivu— Relation of the Mountains of the Moon to the 

 Great Central Valley of the Lakes — Structural peculiarities of these mountains 

 They are an accentuation of the folding characteristic of the region of the 

 Great Central Range — Misapprehensions of Sir Harry Johnston ... 76 



CHAPTER VI. 



AFRICAN PARK LANDS, THEIR APPEARANCE ON ALLUVIAL FLATS 

 CONSIDERED AS EVIDENCE OF RECENT PHYSICAL CHANGE. 



Characters of African Park lands — Artificial appearance of these districts — Their 

 vast extent — Impermanance of Park scenery — A park is an artificial product — ■ 

 Relation of African parks to alluvial plains — Zoned character of the vegetation 

 on freshly-formed alluvial plains — The relation of Euphorbias to bush patches 

 — Gradual conversion of bush patches into forest — The production of an 

 African park marks a phase in a gradual physical change .... 107 



