9 



on the French frontier, some 250 miles east of the Zaria plateau 

 as about 1,000 feet. The same author* describes the "two Hydro- 

 graphic Systems " of Northern Nigeria, that of the Niger and that 

 of which Lake Chad is the centre, the watershed being more 

 or less along the line from Kano to Katsena, and along the northern 

 slopes of the Bauchi hills. 



The Principal Rivers. 



The Niger in its lower course, from the western boundary 

 near Illo to Southern Nigeria, is the principal river. On the 

 north the chief tributaries are the Gulbin draining the province 

 of Sokoto, the Kaduna on which Zungeru is situated (navigable 

 for about 75 miles as far as Wushishi) draining the provinces of 

 Zaria and Nupe, and the Guarara, along the north and west of the 

 province of Nassarawa which " offers no facilities for navigation.'' f 

 On the south there are the Wessa, OH, and Teshi in Borgu. 



The river Benue, which flows in from the German boundary 

 near Garua and Yola, unites with the Niger near Lokoja ; its chief 

 tributaries are on the north the Gongola in Yola, navigable by 

 steam launch as far as Nafada (Bauchi), the Ankwe in Muri, 

 and the Modu in Nassarawa. On the south the Teraba is said 

 to be 200 yards across at its widest part ; it is navigable in the wet 

 season by powerful light draught launches, but in the dry season 

 only by canoe.J There are also the Donga and Katsena in the 

 province of Muri. 



The rivers draining the basin of Lake Chad may be best 

 described in connection with the lake. An account of the 

 drainage system of this region was published recently in the 

 N. Nigeria Gazette, § and is as follows : — 



" The lagoons, which lie in the depression known under the 

 name of Lake Chad, receive their water from various rivers, from 

 the West, South- West and South. 



' k No water comes from the sandy desert to the North and 

 North-East ; and to the South-East some uneven country prevents 

 the Batta from reaching Chad with the waters from Wadai. 



"The Baharel-Gazal to the East, with its continuation to the 

 Bodele and Egei county, lies lower than the level of the Chad 

 and may therefore be regarded as the outlet of the Chad lagoons, 

 probably once the open continuation of the rivers flowing into 

 Chad. To the East, we have at present no proof of its connection 

 with Chad, except the great amount of water, found everywhere 

 in the valley, at a very low depth, which can come from nowhere 

 but the lagoons to the West. 



" The two chief tributaries of Chad are the Kommadugu of 

 Yo, or ' River Wobe,' to give its otficial title in Northern Nigeria, 

 and the Shari. 



* Geog. Journ., Vol. xxiii., 1904. p. 13, N. Nigeria, 

 t Geog. Journ., Vol. xxiii.. 1904, p. 10. N. Nigeria. 



X Geog. Journ., Vol. xiv.. 1899. p. 631, "Regions of the Benue," L. H. Moseley. 

 § N. Nigeria Gaz.. Vol. iii.. No. fi. 1907, pp. 57-58, Report on Lake Chad, by 

 Mr. Hans Viacher. 



