LABORATORY PRACTICE 



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Experiment No. 14 

 Form and Size of Soil Particles 



(Note. Special directions for manipulating the microscope, plac- 

 ing the material on the microscopical object slide, and focusing will 

 be given by the instructor.) 



Place on a microscopical object slide a small amount of. soil ; dis- 

 tribute it in a thin layer, and examine with a low-power microscope. 

 Observe the form and size of the soil particles, distinguish the vari- 

 ous grades of sand, silt, and clay, and make drawings of some of the 

 particles. 



Experiment No. 15 



Pulverized Rock Particles 



Examine with a low-power microscope samples of pulverized 

 mica, feldspar, granite, and limestone. Note any similarity to the 

 soil particles examined in Experiment No. 14. 



Experiment No. 16 

 Reaction of Soils 



For this experiment use peaty, mildly alkaline, and clay soils. 

 Bring in contact with each soil, after moistening with distilled 

 water, pieces of sensitive red and blue litmus paper. Note any 

 changes in color of the litmus paper and state what the results show. 

 In a similar way test the soil from your own farm. 



