SOILS 



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4. Soil studies for water content. Go to the field and with 

 an augur take samples of surface soil, subsurface, and sub- 

 soil. Cover the samples in air-tight fruit jars, and take to 

 the laboratory for further study. To determine the amount 

 of capillary water in the soils, weigh the soil when taken, 

 and after it is thoroughly air-dried weigh again. Note the 

 difference as to capillary water. To determine the hygroscopic 

 water, use the air-dried samples above obtained, note the 

 weight made, then submit the soil to a temperature of 212 

 F. This drives off all hygroscopic water. Weigh again, and 

 the difference should indicate the amount of this form of 

 water. 



5. Determination of volume, weight, and specific gravity 

 of soils. Procure a given volume of soil. Weigh and deter- 

 mine specific gravity by methods common in physical labora- 

 tory. 



6. Capillary rise of water. Fill glass tubes, preferably 

 three feet in length and an inch or two in diameter, with air- 

 dried soil representing as many different types as are avail- 

 able, such as sand, clay, loam, etc. Tie a cloth over the lower 



