Lysimeter Experiments 



11 



down during the process. It was unnecessary to dispose of stones as 

 there were none in the soil. After the bottom 2 feet of soil had been 

 placed in the tanks, 60 gallons of water was run into each to settle the 

 contents. When the tanks were filled, the soil came to within 3 inches 

 of the tops. There has been very Uttle settUng in the cropped tanks, 

 but those that were kept free of vegetation have sunk 2 or 3 inches. As 

 the average weight of soil in a tank was 7133 pounds and the volume 

 occupied was about 74 cubic feet, the weight per cubic foot of the moist 

 soil was about 96.4 pounds. The average weight of each foot of soil 

 placed in the tanks, and the moisture content, are given in table 1: 



TABLE 1. Average Weight of Each Twelve-Inch Later of Soil in Tanks, and Its 



Moisture Content 



First 

 foot 



Second 

 foot 



Third 

 foot 



Fourth 

 foot 



Weight of moist soil (in pounds) 



Moisture in soil (in per cent of dry soil) 



Weight of dry soil (in pounds) 



Weight of dry soil per acre foot (in 

 pounds) 



1,700 



16.6 

 1,458 



3,645,000 



1,768 



15.5 

 1,531 



3,827,500 



1,883 



17.9 

 1,597 



3,992,500 



1,792 



20.1 

 1,492 



3,710,000 



The soil has been classified by the United States Soil Survey as Dunkirk 

 clay loam. A statement of the mechanical analysis of the soil placed 

 in the tanks is contained in table 2. It is a heavy, compact soil, and 

 requires careful management in the field to keep it from puddling. How- 



TABLE 2. Mechanical Composition of Soil in Field prom Which Tanks 1 to 12 



Were Filled 



Kind of soil 



Fine gravel . . . 

 Coarse sand . . , 

 Medium sand . 



Fine sand 



Very fine sand 



Silt 



Clay 



First 



foot 



(per cent) 



0.40 



0.63 



0.83 



1.85 



12.90 



60.83 



22.63 



Second 



foot 



(per cent) 



0.13 



0.37 



0.52 



1.05 



11.27 



53.95 



32.72 



Third 



foot 



(per cent) 



0.07 

 0.27 

 0.33 

 1.05 



7.25 

 52.42 

 38.62 



Fourth 



foot 



(per cent) 



0.08 

 0.18 

 0.28 

 1.10 

 5.18 

 56.50 

 36.67 



II 



