MEASUREMENTS OF CRYSTALS. 



FELDSPAR. (Continued.) 



Figs. 307 and 308. 



M ons 116°20' 



M ony 90 



P on/ Ill 40 



P ons 124 10 



P ony 99 29 



Fig. 309. A compound crystal from New- 

 York. 



Fig. 311. 



M on x 90° 0' 



P onx 128 51 



FELDSPAR. 



Fig. 312. A twin from Orange county. 



Fig. 315 and 316. 



M onn 135° 0' 



Mon^ 90 



M onz 150 



T onz 150 



q on a; 164 40 



Figs. 318 and 319. Twins from Ham- 

 mond, St. Lawrence county. 



