CHAPTER XVI 



The Irrigation problem Drainage Drainage essential to success- 

 ful irrigation Lands poisoned by salt brought to surface by 

 capillary action unless subsoil water-level kept down Mr. 

 John Ashford's tube well pumps water without sand An 

 invention of very great importance Government very slow 

 in proceeding to use it Hydro-electric stations generally useful 

 for irrigation wells, also for the manufacture of nitrolin for 

 manure. 



THE inexperienced water engineer and the inex- 

 perienced agriculturalist who sees a fertile soil which 

 is incapable of yielding any crops because there is 

 no water, thinks that if only water was applied in 

 sufficient quantities the result would be to make 

 very fertile and wealthy districts, but experience 

 shows that it is not enough to bring the water there, 

 that the irrigation canal is only part of the work. 

 The other part of the work is a drainage canal or a 

 drainage pump. An example of this can be found 

 in North Italy in the provinces of Lombardy and 

 Venetia, where there is one of the most wonderful 

 systems of irrigation in the world. It has been 

 working for many centuries. The rains and melted 

 snows come down from the Alps into the rivers and 

 then are guided in irrigation canals into the fields, 

 and from the fields the water flows away into great 



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