508 
MEASUREMENTS OF CRYSTALS. 
MICA. Figs. 385 to 396 inclusive. Page 369. 
Fig. 385. Regular six-sided prism. 
M on M ___ 120°0 / 
M on P ........ 90 0 
Fig. 386. An oblique rhombic prism, with 
transverse sections of about 120° 
and 60°. 
Figs. 387, 390, 391, 392, 393, 394 and 
396, various crystalline forms, the 
cleavages being represented by the 
dotted lines. 
Fig. 388. A six-sided table from St. Law¬ 
rence county. 
M or M' on k _..... 120° O' 
Fig. 389. An oblique rhombic prism from 
Greenwood furnace, Orange county. 
P on a ...._. 114° to 115° 
about 120° O' 
MICA. 
Fig. 395. 
M on l .... 150° 
EMERALD. Fig. 397. Page 374. 
Fig. 397. The primary, a regular six- 
sided prism. 
CHRYSOBERYL. Figs. 398 to 413 inclusive. Pago 
375. 
Fig. 398. The primary, a right rectan¬ 
gular prism. 
Figs. 399 and 400. 
M on ^ ... 125° 16' 
T on s .. 144 44 
i on i .. 120 0 
a on a 
