32 THK ORIGIN OF ALKALI 



lower land 1>\ the seepage water. The land was finally 

 drained, but the alkali content of the soil was not reduced 

 since the quantity added was greater than that lost by 

 drainage. Lining the canal through the alkali-charged 

 shale corrected the entire matter. Soil experts and drain- 

 age engineers, before deciding on the methods of reclaim- 

 ing any alkali tract, should discover all probable sources 

 of the alkali in the area under consideration and select 

 their methods of reclamation accordingly. 



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