Lithological Survey of Schehallien. 361 
3. The same, bluish, highly crystallised. Specific gravity 
= 2.76057. 
4. The same, finer grained, containing thin layers of mica. 
Specific gravity = 2.7413. 
5. The same, gray coloured, and the crystals larger. Spe- 
cific gravity = 2.7302. 
The mean specific gravity of these five specimens is =*■ 
2.76607. 
3 A 
MDCCCXI, 
