BULL. GEOL. SOC. AM. 



VOL. 16, 1904, PL. 80 



Figure 1.— Photomicrograph of Section 89 



Showing the cross-fiber and bifurcation of the amphibolite veins. The relation of th< 

 parts is such as to strongly suggest fracturing by shear-pressure 



Figure 2. — Section (40^1) of typical coarse Amphibolite 

 Showing the curved cleavage partings in a large hornblende 



PHOTOMICROGRAPHS OF AMPHIBOLITE 



