34 FIELD AND LABORATORY STUDIES OF SOILS 



relative length of time which would be required for corn 

 to come up in a drained and in an undrained field? 



Fig. 16. — Corn Planted the Same Day. Tumbler of soil to the 

 left kept saturated while the one to the right is only about 

 half-saturated with water. 



What effect does drainage have upon the air in the soil? 

 Discussion: The rain which falls on the fields would 



