8o 



THE PHYSICAL PROPERTIES OF SOILS 



SIXTEENTH EXERCISE 



MECHANICAL ANALYSIS OF SOILS- 

 BOTTLE METHOD 



By this method an approximate analysis can be 

 made without the use of a centrifugal machine. The 



silt and clay groups are 

 estimated together. 



Duplicate analyses 

 should be made upon 

 prepared stock samples, 

 in order to give the stu- 

 dent practice. As soon 

 as he is familiar with 

 the details of the sepa- 

 ration, field samples 

 should be used. For the 

 method of preparing field 

 samples see the instruc- 

 tions given on page 96. 



METHOD OF MAKING THE 

 SEPARATIONS 



Take twenty or thirty 

 grams of dry, pulver- 

 ized, sifted soil ; mix 

 thoroughly, and dry in 

 the oven and cool in a 

 desiccator. Weigh out 

 two 5-gram portions. 

 Ignite one of these samples and calculate the loss on 

 ignition. Transfer the other sample to an 8-ounce 



APPARATUS USED IN THE BOTTLE 

 METHOD OF MECHANICAL 



ANALYSIS {after M osier). 



