366 GEOLOGY OF THE SECOND DISTRICT. 



3. Serpentine. Fowler, Pitcairn, Edwards, Ciouvcrneur. 



4. Albile, appears to form a constituent part of the white granite at Gouverneur. 1 found, in one 

 instance, beautiful hemitrope crystals of this substance in the Coal-liill mine. 



5. Pyroxene, occurs in fine crj-stals in Gouverneur. 



6. Scapolite, is associated with the former, and with feldspar, in large crystals at the same locality 



also in the lead mine. 



7. Tourmaline. Near Richville, this substance has been procured of a green color; at Dekalb, it is in 

 fine crystals, some of which are dark brown inclining to green. Brown tourmaline is common in 

 the primary limestone. 



8. Phosphate of lime. Probably the finest crystals known have been procured at Rossie. The locality 

 formerly resorted to in Gouverneur, is nearly exhausted. 



9. Quartz in the dodecahedral form, was quite abundant at Edwards. Most of the mines of specular 



oxide of iron furnish large quantities of implanted crystals. 



10. Specular oxide of iron. In splendent crystals. 



11. Magnetic oxide. Ghamont. 



12. Hornblende, in fine crystals, in Edwards. Fine tremolite occurs in the north part of Gouverneur. 



13. Sulphate of strontian, var. termed CeZcs/JHC. Coal-hill mine, Rossie, in fine blue crystals ; at the 

 Osbom marsh, Gouverneur, in radiated masses. 



14. Sulphate of barytes, associated with the specular oxide of iron. 



15. Fluor spar, in small quantities, in Gouverneur. 



16. Sulphuret of iron. Coal-hill mine. 



17. Sulphuret of copper and iron. Canton. 



18. Zircon. Rossie, in fine brown translucent crystals, associated with hemitropic crystals of feldspar 

 and phosphate of lime in primary limestone. 



19. Mica, in fine six-sided tables, at Pope's mills in Edwards ; copper-colored, in serpentine, Gouver- 



neur. 



20. Sphcne ? A brown mineral whose appearance is like sphene, but supposed to be different, in Rossie. 



This mineral, however, occurs well characterized in Gouverneur. 



Recapitulation of the leading Facts in the Geology of St. Lawrence County. 



1. In the Primary system, the great developments are calcareous, together with the re- 

 markable blending of granite and gneiss with the calcareous mass. This peculiar formation 

 is confined to the southwestern towoiships. 



2. Connected with the preceding, are the numerous veins of specular iron ore, but which 

 are more intimately related to the primary limestone and serpentine than granite. 



3. The limestone forms the same aggregate with serpentine, as in Essex already described. 



4. These rocks embrace the principal simple minerals. 



5. In the southeastern townships, we find, as in Essex, a large development of the mag- 

 netic oxide of iron, which appears to be associated with hypcrsthene rock. 



6. The sedimentary rocks embrace only the two lowest in the New- York system ; the Pots- 



