BULLETIN 835, IT. S. DEPARTMENT OF AGRICULTURE. 



sent that part of the soil column immediately below the original wet 

 soil area. Likewise the distances 34 inches and 40 inches at the bot- 

 tom of the table represent that part of the original air-dried soil on 

 top of the original wet soil. The other part of the table has a similar 

 arrangement, except that the .distances were taken from the bottom of 

 the boxes. Referring to the Riverside soil it is found that the distri- 

 bution of moisture from the bottom of the box upward is quite uni- 

 form until near the upper extremity of the original wet area. At a 

 distance of 47 inches 9.19 per cent of moisture is found, while at 50 

 inches there is 6.6 per cent of moisture. In corresponding distances 

 at the bottom of the box, represented by 22 inches and 18 inches, re- 

 spectively, a much less variation in the percentage of moisture is 

 found. 



Table 47. — Distribution of moisture by percentage in the soil boxes. 



Idaho soil, initial 

 moisture 20 per cent. 



Riverside soil, initial moisture 

 15 per cent. 



Distance. 



Moisture 

 content. 



Distance. 



Moisture 

 content. 



Distance. 



Moisture 

 content. 



Inches. 

 — 5 

 _2 



Per cent. 

 9.46 

 11.31 



Inches. 



3 

 6 

 9 



12 

 15 



IS 



Per cent. 

 5.65 

 7.08 

 8.25 

 8.61 

 9.09 

 9.42 



Inches. 

 5 

 8 

 11 

 15 

 19 

 22 



Per cent. 

 4.74 

 6.90 

 8.05 

 8.81 

 9.04 

 S. 75 



2 

 6 

 12 

 18 

 24 

 28 

 31 



14.09 

 14.46 

 15.05 

 16.00 

 15.44 

 15.51 

 15. 40 



22 

 25 

 26 

 31 

 34 

 37 

 40 

 44 

 47 



10.79 

 10.20 

 10.34 

 10.60 

 10.00 

 9.86 

 9.38 

 9.50 

 9.19 



24.5 

 27 

 30 

 34 

 38 

 42 

 46 

 50 

 54 

 58 

 62 

 66 



11.40 

 12.37 

 11.28 

 11.50 

 11.05 

 11.13 

 10.45 

 10.40 

 9.35 

 9.48 

 8.43 

 8.92 

 8.2.8 



34 

 40 

























50 

 58 



6. 60 

 3.90 

















70 









74 



77 



4.99 

 3.28 













It would seem from Table 47 that gravity has played its part in 

 conjunction with capillarity in a rather uniform distribution of soil 

 moisture from the wet soil area to the dry soil area. Upon the other 

 hand it is found in taking the moisture percentages that gravity has 

 very materially retarded the upward movement of the soil moisture. 

 It is found, for instance, that the percentage of moisture found im- 

 mediately below the original wet soil area is almost double the per- 

 centage of moisture found immediately above the upper end of the 

 original wet soil area. 



If such a condition as this maintains in the field, and there is no 

 reason to believe it does not, then we can expect that capillarity and 

 gravity will tend to a deep penetration of the moisture. The figures 



