26 



NEW YORK STATE MUSEUM 



PYRAMIDS 



Pyramid of the first order 

 Pyramid of the second order 

 Dihexagonal pyramid 



Fig. 92 



Fig. 93 





Fig. 95 



Fig. 96 



PRISMS 



FIG. 



92 

 93 

 94 



Fig. 94 



Fig. 97 

 FIG. 



95 



Prism of the first order 

 Prism of the second order 96 



Dihexagonal prism 97 



The basal pinacoid is shown terminating the prisms in fig. 95- 

 97. The relation of these forms to one another is shown in fig. 



Fig. 98 Fig. 99 Fig. 100 



98. Two combinations in the normal group are shown in fig. 99 

 and 100, which represent crystals of beryl. 



