480 



MEASUREMENTS OF CRYSTALS. 



ClUARTZ. (Continued.) 



Fig. 152. 



Pona 145°22' 



P one 165 30 



a one 159 50 



a on e 175 30 



a OTkZ 137 51 



a anz" Ill 15 



c onz 145 30 



Figs. 157, 158, 159, 160. 



Pona 145°22' 



P one 165 



Pon< 154 



aUARTZ. 



P"onf 103 50 



a on z 137 51 



eox\.z 145 



r on t 133 50 



( on z 155 



Fig. 161. A twin from Middleville, Her- 

 kimer county. 

 Fig. 161 {bis.) Two crystals crossing 



each other. It may be accidental. 

 Fig. 162. 



P on 2' or P' on z 103°20' 



