S70 



THE EEGOLITH 



tions which characterize the Atlantic slopes of the American 

 continent. 



The capacity of soils for moisture has been the subject of 

 experiment, and is fonnd to vary widely, being naturally largely 

 dependent upon the size of the individual particles and the con- 

 sequent amount of interspace. Whitney states^ that sub-soils 

 of Maryland truckland having 45% of interspace will hold but 

 22.41% by weight of water, when this space is completely filled. 

 The sub-soil of the Helderberg limestone, having 65% of space, 

 will hold 41.22%. King^ gives the following table to show 

 the actual amount of water held by field soils when their sur- 

 faces are only 11 inches above standing water, this water having 

 been lifted into them by capillarity: 



Amount of Water in Soils 



Soil 



Per Cent 

 OP Watee 



PotJNDS OP 



Water 



Inches op 

 Water 



Surface foot of clay loam contained . . . 

 Second foot of reddish clay contained . . 

 Third loot of reddish clay contained . . 

 Eourth foot of clay and sand contained . 

 Fifth foot of fine sand contained .... 



32.2 

 23.8 

 24.5 

 22.6 

 17.6 



23.9 

 22.2 

 22.7 

 22.1 

 19.6 



4.59 

 4.26 

 4,37 

 4.25 

 3.77 



Total 







110.5 



21.24 



According to Meister, different soils show water-holding eapaci- 

 ties as follows/ 



Water Holding Capacity of Soils 



Kind op Soil 



Clay • 

 Loam . 

 Humus 

 Peat . 

 Garden 

 Lime . 



Per Cent 

 op Water 



IMBIBED 



60.0 

 60.1 

 70.3 

 63.7 

 69.0 

 59.9 



Kind of Soil 



Chalk .... 

 Gyseous. . . . 

 Sandy (82 % sand) 

 Sandy (64 % sand) 

 Pure quartz sand. 



Per Cent 

 OF Watek 



IMBIBED 



49.5 

 62.4 

 45.4 

 65.2 

 46.4 



^ Some Physical Properties o£ Soils, Bull. No. 4, U. S. Dept. of Agricul- 

 ture, Weather Bureau, 1892. 



2 The Soil, p. 159. 



» Handbook of Experiment Station Work, IT. S. Dept. of Agriculture, 

 1893, p. 317. 



