PLATE XII 



PHOTOMICROGRAPHS OF GNEISS, SCHIST AND GRANODLORITE 



Fig. 1. Interbedded gneiss. 



Catskill Aqueduct tunnel underneath Harlem River at High Bridge, 



New York City. 

 Magnified 22.5 diameters. Crossed nicols. 



Fig. 2. Fordham gneiss. 



East of High Bridge, New York City. 

 Magnified 22.5 diameters. Crossed nicols. 



Fig. 3. Cyanite schist. 



West 120th Street, east of Amsterdam Avenue, New York City. 

 Magnified 22.5 diameters. Crossed nicols. 



Fig. 4. Hornblende schist. 



South shore, Croton Lake, New York. 

 Magnified 22.5 diameters. 



Fig. 5. Harrison granodiorite. 

 Greenwich, Connecticut. 

 Magnified 22.5 diameters. 



