WATER PENETEATION IN GUMBO SOILS. 



Table III. — Depth of soil penetrated and total distance from the surface 

 reached ichere water teas kept standing for 10 days in holes 8 inches in 

 diameter bored to different depths. 





Hole No. 



Specification. 



9 



10 



11 



12 



13 



14 



15 



16 



Depth of hole inches. . 



Depth of soil penetrated do 



Depth below siu-face to which water 

 penetrated inches. . 



Surface. 

 22 



22 



6 

 15 



21 



9 

 12 



21 



12 



8 



20 



15 



7 



22 



18 

 10 



28 



21 

 11 



32 



24 

 11 



35 



Water added at all points within the cracked area penetrated 

 almost exactl}^ the same distance. In each case it penetrated through 

 the cracked soil and about 7 inches into the compact soil beneath. 

 Where water was applied below the cracked area the total distance 

 reached hj water penetration varied with the depth below the surface 

 at which the water was applied. The distance that it penetrated into 

 the compact soil was quite uniform. That a constant, though ex- 

 ceedingly slow, movement of moisture did take place in the compact 

 layer is shown by a comparison of Tables II and III. These show 

 that for all the points within the compact layer the depth penetrated 

 when water was kept standing for 10 days was greater than when 

 it stood for a shorter period of time. 



A third experiment was performed in order to determine as nearly 

 as possible the rapidity with which water movement takes place 

 within this compact layer and the depth in it to which varying 

 amounts of water w^ould reach. A third series of borings was made 

 to a uniform depth of 18 inches. The amount of water added, the 

 time required for the water to disappear, and the depth to which it 

 penetrated are shown in Table IV and figure 4. The distance that 

 the water penetrated in each case was determined as soon as possible 

 after the water disappeared. 



Table IV. — Time taken for various quantities of tvater to disappear and I lie 

 depths of penetration in each case frovi the bottoms of a series of holes IS 

 inches deep. 



Specification. 









Hole No. 









17 



18 



10 



20 



21 



22 



23 



24 



Water added: 



Quarts 



1 



2 















fJallon.s 



1 



5 

 40 



1 



32 

 40 



2 



48 

 30 



2 



57 

 30 



4 

 43 



a 2 



Time rwjulred to disappear: 





3 

 10 





Minijtwj 



6 









10 



lJ«!pth of nenetratton below the bot- 

 U>m of the hole Inches. . 



I>epth of penetration below the sur- 

 faf* inches. . 



a 



23 



ft 

 24 



21 



Zi 





51 

 23i 



5 

 23 



24.1 



o Three times. 



