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CHAPTER V. 



DRAINAGE AND IRRIGATION. 



As a rule, owing to the heavy nature of the rainfall, drainage 

 is a matter of necessity in the tropics, more especially nearer to 

 the equator, where more rain falls, and on irrigated land, where 

 water is artificially supplied. While in North India drains of 

 the kind seen in Europe are at times employed, as a rule, if 

 there be any drains at all, they are simply open watercourses 

 cut at intervals. On hilly ground they follow comparatively 

 gentle slopes around the declivities, and do not run straight 

 down the slopes. 



Occasionally, as for instance in the coastal region of the 

 Malay Peninsula, such drains are not enough, on account of the 

 very heavy rainfall, the very flat nature of the country, and its 

 very slight elevation above sea level. In such cases large 

 drains, often in fact small canals, have to be cut at fairly 

 frequent intervals, and it becomes a matter of great importance, 

 before opening land, to make sure that it will be possible to 

 drain it. The first comers of course will be all right, but later 

 comers may have to buy up land from their predecessors to get 

 their own drains through to the sea or to a river. In such 

 cases we have suggested that the Government should at an 

 early date mark out the country into approximate squares of a 

 mile or so by lines of reservation for drains (which would of 

 course also ultimate supply canal transport), just as we have 

 suggested for roads, so that a purchaser of land may find that 

 it abuts somewhere upon a drainage reservation, along which 

 the Government will then make a drain to convey away his 

 surplus water. Of course in such cases land would only be 

 sold near to existing drains, not far away back in the forest. 



