The Story-Book of the Fields 



When practised in this way draining is a 

 simple matter ; but it presents a serious 

 difficulty. Sooner or later the layer of stones 

 will be filled up by the earth transported by 

 the water. For this reason the stones are 

 sometimes replaced by faggots of branches 

 which are not so easily obstructed ; but a 

 better result is obtained by channels of 

 earthenware at the bottom of the trenches. 

 Sometimes these channels are composed of 

 tiles similar to those used for roofs, resting 

 on flat tiles called sleepers. Or again, com- 

 plete pipes of earthenware are used, loosely 

 fitted to one another, so that the water may 

 enter the channel through the joints. 



The advantages of draining are not limited 

 to drawing off the water from ground that is 

 too damp and to promoting the access of air 

 to the roots of plants. It also keeps up a 

 constant moisture in the ground owing to the 

 water that remains in the drains. When the 

 base of a heap of sand is immersed in water 

 the moisture may be seen to rise gradually 

 until it reaches the top. In the same way in 

 dry seasons the water in the channels will 

 penetrate upwards till it reaches the roots, 

 so that the water which is at certain times 

 useless or even harmful is held in reserve 



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