140 OLDHAM : SANDHILLS OF CLIFTON NEAR KARACHI. 



similarity between the material of which the dredgings are composed 

 and that which forms the sandhills at Clifton. On a further ex- 

 amination of the question, however, this explanation falls. In the 

 first place I have only estimated the material which has accumulated 

 opposite and to the west of Clifton, and made no allowance for the 

 great belt of sandhills east of Clifton or those which have been 

 formed round Ghizri. If these were taken into consideration, it would 

 be found that the amount of sand which has come ashore much 

 exceeds what has been removed from the harbour of Karachi. 



A second point is that, even if we assume that all the dredgings 

 are washed ashore at Clifton, which is far from being the case, yet 

 of the 207 millions of cubic feet removed from the harbour no less 

 than 54 millions come from the entrance section, and this represents, 

 practically in its entirety, material which has drifted round the 

 Manora Point and of which quite half, as shown by the returns of 

 silting in this section, has been merely helped on its way down the 

 coast. If we add what may have drifted up the harbour with the 

 tide, into the lower harbour, it becomes evident that quite one quarter 

 of the material removed from the harbour is stuff which, in the 

 natural state of affairs, would have drifted down the coast and reached 

 the Clifton beach at most a few years later than it actually did. 



From these considerations it is evident that the dredging has 

 been quite a minor factor in the growth of the Clifton sandhills, for, if 

 we may judge from the growth of land and shallowing of the sea 

 to the eastward, it would seem that the amount of material removed 

 from the Karachi harbour is quite insignificant in comparison with the 

 amount of the natural drift along the coast. The effect of dredg- 

 ing the harbour and dropping the dredgings off Clifton may have 

 slightly accelerated the growth of the sandhills, but if the Chinna 

 creek had not been closed the foreshore would have been kept clear, 

 and on the closing of this outlet it would have grown almost, if not 

 quite, as rapidly as it has done. 



So far, then, as the improvement of the harbour has affected 

 Clifton, there is nothing which need be considered except this one 

 work, but for it the dumping of dredgings off Clifton would have 

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