EXERCISE A-18. TO STUDY THE OPERATION OF TILE 



DRAINS. 



Equipment: Drainage apparatus; dipper; glass tumbler; 

 sample of sandy loam soil. 



Method: Fill the drainage apparatus to within an inch 



Fig. 17. — To the Left, a Tin Can Arranged to Show the Operation 

 of Tile Drains. To the Right is the Grahani-McCall Apparatus. 



of the top with sandy soil. If a drainage apparatus is 

 not available, a tin can may be used after having punched 

 two holes in the side as shown in the diagram. 



Slowly pour water over the surface of the soil and note 

 the result. 



To operate the Grahara-McCall apparatus, fill the ves- 



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