2 PAGAN TRIBES OF BORNEO chap. 



two principal mountain chains which determine the 

 main features of the river-system, there are several 

 isolated peaks of considerable height, and a minor 

 ridge of hills runs from the centre towards the 

 south-east corner. With the exception of the 

 northern extremity, which geographically as well as 

 politically stands apart from the rest of the island, 

 the whole of Borneo may be described as divided 

 by the two principal mountain chains into four large 

 watersheds. Of these, the north-western basin, 

 the territory of Sarawak, is drained by the Rejang 

 and Baram, as well as by numerous smaller rivers. 

 Of the other three, which constitute Dutch Borneo, 

 the north-eastern is drained by the Batang Kayan 

 or Balungan river ; the south-eastern by the Kotei 

 and Banjermasin rivers ; and the south-western by 

 the Kapuas, the largest of all the rivers, whose 

 course from the centre of the island to its south- 

 west corner is estimated at 700 miles. Although 

 the point of intersection of the two principal moun- 

 tain chains lies almost exactly midway between the 

 northern and southern and the eastern and western 

 extremities of the island, the greater width of the 

 southern half of the island gives a longer course to 

 the rivers of that part, in spite of the fact that all 

 the six principal rivers mentioned above have their 

 sources not far from this central point. The prin- 

 cipal rivers thus radiate from a common centre, the 

 Batang Kayan flowing east-north-east, the Kotei 

 south-east by east, the Banjermasin south, the 

 Kapuas a little south of west, the Rejang west, and 

 the Baram north-west. This radiation of the rivers 

 from a common centre is a fact of great importance 

 for the understanding of the ethnography of the 

 island, since the rivers are the great highways which 

 movements of the population chiefly follow. 



In almost all parts of the island, the land adjoin- 

 ing the coast is a low-lying swampy belt consisting 



