PLAIN NORTH OP ADEN. 23 



rapidity. The natives further say that (unlike Shaik Othman) increas- 

 ing" the depth of the wells produces no brackishnesSj and here again 

 I believe they are right. I do not know what the elevation of Lahej 

 above the sea may be^ but even if the wells were sunk much below sea 

 levelj the distance from the sea is probablj^ too great to allow of any 

 infiltration from it^ or even if such could take place^ it would be quite 

 inappreciable in comparison to the influx of fresh water. According to the 

 nativeSj the wells yield an equal quantity of water throughout the year. 

 The water-bearing stratum must no doubt be kept saturated^ as long as 

 the river contains running water to soak down to it^ that is to say all 

 the year round since the river- is perennial. 



If then the present wells^ sunk a few feet below the water-level^ 

 yield abundant water to supply the demand upon them for irrigation^ 

 what would be the yield of one or more wells sunk 50 or 100 feet below 

 that line ? There is of course the possibility that the solid rock^ or less 

 porous strata^ might be met with before such depth should be reached, 

 but assuming that the gravel bed extends down to a sufficient depth, 

 there cannot be the least doubt, taking into account its highly pervious 

 nature, which would allow the water to flow rapidly in from a very 

 large circumference, and that the river is at hand to supply the porous 

 stratum with water as fast as it is drawn off, that a well sunk to a con- 

 siderable depth below the water-level would yield a very large quantity 

 of excellent water, and that this is one means by which Aden could be 

 fully supplied. Of course it would be necessary to raise the water to 

 the surface by some description of pumping apparatus, and power 

 would have to be provided for such purpose. It is worthy of considera- 

 tion whether such could not be found in the wind. From information 

 supplied to me by the Harbour Master at Aden, it appears that the 

 prevalent winds there are south to south-west during the south-west 

 monsoon, from the beginning of June till the end of August. During 

 September and beginning of October, little or no breeze and variable 



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