Aug. 20. 1917 



Relation of Soil Water Movement 



409 



With soil Q the water did not advance evenly, but took a zigzag 

 course, first on one side and then on the other. For this reason the 

 data do not satisfactorily indicate the rate of movement of the water 

 during the five days, and consequently the soil is not mentioned in those 

 tables dealing with the rate, 



RELATION OF APPARENT SPECIFIC GRAVITY TO MOISTNESS AND 

 HYGROSCOPICITY 



The weight of the moistened soil placed in each cylinder was deter- 

 mined, and from this and the capacity of the cylinders (1,730 c. c.) 

 the weight of oven-dried soil and its apparent density have been cal- 

 culated (Table XI). It will be seen that with any one soil the differ- 

 ence from experiment to experiment was small. With all the soils 

 except I the density is lowest in the moistest form, and with all except 

 J it is highest in the driest. 



If we divide the soils into three groups according to texture, it will 

 be seen that those in the intermediate group are intermediate also in 

 apparent density, but when we compare the different members of each 

 group there is no direct dependence of the relative density upon the 

 hygroscopicity. 



Table XI. — Dry weight {in grams) of the soil contained in the different cylinders and its 



apparent specific gravity 



