SOIL 



(Chapter 11) 



1. Weigh a quart fruit can full of rich black soil. 

 Dry thoroughly by holding over a fire, being careful not 

 to burn, and then weigh again. The difference is the 

 weight of the water content of the soil. What per cent 

 of the soil is water? 



2. Place the soil in a pan and burn it. Cool and weigh 

 again. The loss in weight is the humus or organic mat- 

 ter of the soil. What per cent is organic matter? The 

 portion remaining is the mineral matter. What per cent 

 is mineral matter? 



3. Fill three small flower pots with finely pulverized 

 soil, one with clay, one with sand and one with loam. 

 As you weigh these add enough to make them weigh the 

 same. Pour water slowly into each pot until the soils 

 are thoroughly wet and the water begins to run out at 

 the bottom. Then weigh the pots of wet soil, and find 

 which is holding the most water. Which soil took in 

 the water the quickest? Which the most slowly? In 

 case of heavy rain, which soil would absorb the great- 

 est amount of water ? Notice which flower pot continues 

 to drip the longest and which drains the most rapidly. 

 What bearing does this experiment have on farming? 



4. Break bottoms from three large vinegar bottles of 

 uniform size. Fill one with loam, one with clay, and one 

 with sand. Tie a cloth over the mouth of each bottle 

 and place in a rack as shown in Fig. 127 so that the ends 



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