PRACTICE XXXII 



STANDARDIZATION OF THE EYEPIECE MICROMETER 



Use eyepiece and stage micrometers. 



Place both micrometers in position and determine for each of 

 the objectives the number of divisions or spaces of the eyepiece 

 micrometer that corresponds to 1, 0.1, 0.01, and 0.001 millimeters 

 of the stage micrometer. 



Show on the table below the number of spaces of the eyepiece 

 micrometer that corresponds to the size of the various grades of 

 soil particles. By means of this table and the microscope with 

 the eyepiece micrometer it may be determined whether the 

 separations are properly made in the following practice. 



65 



