498 



MEASUREMENTS OF CRYSTALS. 



FELDSPAR. (Continued.) 



Figs. 307 and 308. 



Mons 116°20' 



M ony 90 



P on/ Ill 40 



P ons 124 10 



P on y 99 29 



Fig. 309. A compound crystal from New- 

 York. 



Fig. 311. 



M on .r 90° 0' 



P onx 128 51 



FELDSPAR. 



Fig. 312. A twin from Orange county. 



Fig. 315 and 316. 



Monn 135° 0' 



Monq 90 



Monz 150 



T onz 150 



q onx . 164 40 



Figs. 318 and 319. Twins from Ham- 

 mond, St. Lawrence county. 



