*- If 





4- 



Figure 12-3. Boyle's law or gas-expansion porosimeter. 



given herein. The specimen is then crushed to its individual grains, washed free 

 of oil by any satisfactory solvent, and dried; and the volume of the grains is 

 measured in a pycnometer with any suitable liquid. The porosity thus determin- 

 ed, of course, is total porosity, whereas the other methods described herein 

 measure effective porosity. 



237 



