544 STUDIES FOR STUDENTS 



EXPLANATION OF PLATE I 

 RESULTS OF CRUSHING GRANITE AND RHYOLITE 



The figures in this plate illustrate some of the more perfect cones 

 resulting from crushing the stronger samples of granite and rhyolite. 

 Fig. i is a typical result for granite of this class, while Fig. 3 is a 

 typical rhyolite cone. This latter cone resulted from crushing a two- 

 inch cube of granite, which gave a test of nearly 48,000 pounds per 

 square inch. It will be further observed that Figs. 4 and 5 have 

 wedge-shaped apices similar to those illustrated in PI. IV, Fig. 3. 



