Heavy Rain falls during the S. W. Monsoon. 89 



and the damp season of the S. W. monsoon from April to 

 October, are by no means so sharply defined on these islands 

 as on the adjoining coasts of the mainland, the quantity of 

 annual rainfall must be enormous. At certain times it is not 

 much less than 100 or even 150 inches, and yet it probably 

 is not so high as that presented by other localities, which ex- 

 perience the regular changes of the monsoons, as for instance, 

 in the Straits of Malacca, where the annual rainfall is 208 

 inches, or Mahableshwur south of Bombay, where it amounts 

 to no less than 254 inches ! March is the dryest month in the 

 year. During the whole of the month, which Ave spent on 

 the islands or in their immediate vicinity, we only had three 

 sharp thunder-storms. These become more frequent and 

 severe during April, until about May or June the S.W. mon- 

 soon sets in and envelopes the islands in rain-clouds. Where 

 some special physical configuration of the soil does not admit 

 of the rapid carrying off of the redundant deluge of rain, 

 the island must necessarily be unusually well off for water. 

 Of the correctness of this theory we were enabled thoroughly 

 to satisfy ourselves, since the close of the dry season is neces- 

 sarily unfavourable to there being any water remaining in the 

 streams and brooks ; notwithstanding which even the smallest 

 of the islands, Pulo Milu and Kondul, although their rivulets 

 had ceased to flow, possessed a sufficient supply of sweet 

 drinkable water among the numerous basin-shaped pools that 

 occur in the beds of the various streams. From the forest- 

 covered sloj^es of Tillangschong also, small streams of fi'esh 



