564 STUDIES FOR STUDENTS 



EXPLANATION OF PLATE XI 



Fig. 1. — Section No. 4702 (X 12). Granite from Waupaca. This 

 rock contains a greater variety of minerals than No. 4711. Besides 

 quartz and feldspar there is an abundance of chlorite, epidote, and, in 

 some places, biotite. The individuals are interlocking, but less regular 

 than in many granites. 



Fig. 2. — Section No. 4711 (x 12). Granite from Granite Heights. 

 The dark colored parts are feldspar, and the lighter colored are quartz. 

 This section illustrates nicely the close, interlocking character of the 

 different individuals which contributes largely to the strength of the 

 rock. 



