APPENDIX A 



disuse and almost concealed by reeds. The largest and 

 most important water-holes are : Eil-ad, Gombe-Barsa, Jara, 

 Gama Gar, Gulola and Tubtu, I saw many others, but they 

 were small and not to be relied on except immediately after 

 a plentiful rainy season. 



As regards the Bisahu-Hamu, marked on every map 

 as an important swamp, its name is unknown to the natives, 

 but north of Bussa Berora there is a large plain covered 

 with coarse grass that no doubt becomes swampy in the 

 rainy season, a peculiarity not confined only to that 

 locality. 



During the rains and shortly after there is surface water 

 almost everywhere in the bush in little shallow pans. 

 Although containing little water, and that highly unpleasant 

 in quality, these rain-pools are often invaluable to the 

 traveller. 



2. Lak Dera (" Lak," Galla word for a non-permanent 

 stream ; " Dera," Somali for Long). — The Lak Dera is a con- 

 tinuation of the river Uaso Nyiro. I followed the course of 

 the river (with the exception of about thirty miles between 

 Sereda and Madoleh) from longitude 40° 43' E. to Marti 

 Mountain, where the Uaso Nyiro is well known, and I can 

 positively state that the river bed is continuous all the way 

 without a break, even in the two Lorian Swamps, and that 

 the name is changed, only where permanent water ceases and 

 the Uaso Nyiro, which grows narrower and shallower from 

 Marti Mountain eastwards, finally and very gradually sinks 

 underground at Madoleh, some eleven miles below the second 

 swamp. Eastwards from the latter place the Lak Dera 

 varies in breadth from 10 yards to 300 yards, the bed being 

 generally sandy and much overgrown with bush and jungle. 

 The fall is very slight, especially at first, and averages about 

 I in 600, though just below Toor Guda there is a stretch 

 of I in 200. It runs in a very broad shallow valley, 

 bounded on north and south above Sereda by low rounded 

 hills which send down spurs towards the river ; but the only 

 important feeder, if a dry stream may be called such, is the 

 Lak Aboloni, which rises in a series of small swamps, almost 

 due north of Liboyi. On each side of the Aboloni and 



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