26 VREDENBURG : RECENT ARTESIAN EXPERIMENTS IN INDIA. 



relatively abundant rain that falls on the hills where it would be 

 of no use owing to the steepness of their bare slopes. 



So long as they are left to their own devices, it is not within 

 the means of the inhabitants of these sparsely populated districts 

 to obtain this water through artesian wells, as they do not possess 

 suitable appliances to reach the requisite depth. But with their 

 simple methods they can obtain the same supply by the much more 

 laborious task of driving a horizontal gallery through the inclined 

 beds in the lower portion of the talus. These are the works known 

 as " karez " or"kanat" which have already been mentioned in a 

 previous paragraph. The water is not under great pressure where 

 the stratum containing it is penetrated by works of this kind, but 

 the great surface of percolation in the gallery allows the collection 

 of an abundant supply. The first attempt to tap this supply by 

 means of a boring was made at Quetta in 1889. The experiment 

 was eminently successful and, since then, many other borings have 

 succeeded, while experiments of a promising nature have also been 

 attempted in the plain of Pishin. From the irregular conformation 

 of these deposits, the prospects of success at any particular point 

 within the area covered by them cannot be accurately predicted. 

 The tongues of gravel must overlap one another in a very irregular 

 manner, and there is no means of knowing their lateral extension. 

 At one place, a water-bearing stratum may be struck at a much 

 smaller depth than at another, while it may also happen that the 

 gravel may be missed entirely, which explains why some borings 

 have been unsuccessful, though surrounded by others that have met 

 with water-bearing strata. In fact in all artesian reservoirs like 

 this one, consisting of recent undisturbed deposits, the only indi- 

 cation that can be given with any degree of accuracy is the main 

 boundary of the area within which success is possible, but success 

 at any particular point within that area must remain, to a great 

 degree, a matter of chance. 



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