Gil the Mineralogy of New York Island. 191 



elsewhere, in masses an inch in diameter, as well as in distinct 

 hexedral tables. 



The only variety of Hornblende of much interest is the 

 anthophyllite from near 57th street, where the specimens, when 

 not weathered, are finely fibrous, radiated, or interlaced with a 

 silky lustre, and very tough. 



From the same serpentine rocks was obtained a number of 

 good specimens of chrysotile, which has a fair lustre, but the 

 fibres have a very harsh and brittle feel. Altogether, it is 

 deserving of further examination. 



Both magnetic and specular iron are found sparingly, the 

 latter accompanying crystals of albite, apatite, and in one or 

 two instances, green sphene. A locality of these minerals in 

 38th street promised some good specimens, but it was soon 

 covered with buildings. 



The feldspar near Broadway and the Central Park has fur- 

 nished orthite in good crystals. It occurs in slender black 

 prisms, sometimes two inches long, of a pitchy lustre like the 

 Norwegian mineral, and fully as good. 



It is more than probable that a closer examination of the 

 rocks containing the orthite, will disclose some of the other 

 species of minerals which often accompany it, and which con- 

 tain cerium, jlorium, or titanium. 



From a large mass of rock near Manhattanville, I broke two 

 or three specimens of graphic tellurium. The rock, which was 

 three or four feet in diameter, did .not appear to be a boulder, 

 though I do not remember to have seen similar rock in situ 

 upon the island, nor indeed anywhere in our State. It bears 

 some resemblance to that from Transylvania, in which the 

 tellurium there occurs. 



The foregoing minerals were all found within the limits before 

 mentioned, and for those from different parts of the island, I 

 am indebted to others both as regards the localities and a 

 description of the specimens. 



Mr. J. Deems of this cit}*, some time since, found crystals of 



