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PRACTICE 22 



Testing the Tenacity of Moist Soils. 



Use clay, silt and loam. 



Weigh out about 200 grams of each soil to be tested. Pour the 

 soil in a pan and mix with it by hand enough water to bring it to 

 maximum adhesiveness as near as you are able to judge. 



Note amount of water used. 



Now holding the cages firmly together, pack the mud into them 

 and scrape the top off level. Attach the weight pan and carefully 

 pour sand or fine shot into it until the soil column breaks. Weigh pan 

 and sand. Put the movable cage in place but not having the soil 

 surface in contact, and determine the weight necessary to overcome 

 friction. 



Subtract this from the previous weight. The result represents 

 the tenacity of a column of moistsoil one square inch in cross section. 



With the same roll of mud, make three tests, using different 

 amounts of water, noting the amount added for each soil each time. 



How does fineness of grain effect tenacity? 



What effect would undecomposed organic matter have on tena- 

 city? 



What term is applied to very tenacious soils? 



What differences in the working of these soils? 



