LIST OF PLATES. 



Plate I. Mica cutters at work. 

 „ II. Folded pegmatite veins in schist. 

 „ III. Mass of quartz in a mica quarry. 

 „ IV. Entrance to a mica mine. 

 „ V. " Book" of mica exposed in quarry. 

 „ VI. Percussion-and pressure-figures in muscovite. 

 „ VII. Crystal of muscovite, showing symmetrical disposition of optic axial 



plane, percussion-figure and natural pressure-figure. 

 , VIII. Map of India, showing occurrences of marketable mica, (i'' = 365 



miles.) 

 „ IX. Map of the Bengal mica mining belt. (1" = 4 miles.) 



