-if Boston and its Viciniti/ 



169 



It 19 rather difficultly frangibl 

 The fragments are splintery. 

 The specifick gravity is about 



Chymical Character, 

 Before the blowpipe it melts into a black enamel or sla^. 



O 



(jreological Situation and Localities. 

 imall quantities in Araycdaloid, an 



d 



rounded 



fragments of Greenstone, at Brigl 



and massive, in Quartz 



which traverses rolled masses of Greenstone, at Dedha 



here 



the fibres of 

 exposure to 

 saw-dust. 



are sometimes an inch long j by Ion 

 ley become disintegrated and resembl 



O 



SPECIES XIY. —UOR^^BLE^^DE. 



Subspecies I. — Common Hoimhlende. 



Common Hornblende, Cleavelandj, p. 335. Ideniy Jameson^ vol, i. p. 55 

 Idem, AikiUf p. 236. Hornblende, KirwaUy vol. u p. 213. 



I • 



External Characters. 



It? colours a?e grey and black. Of grey, it occurs greenish 

 grey and blackish grey ; of black, greyish black and raven black. 



Its lustre is glistening and glimmering, and is peady. 



It is slightly translucent at the edges. 



It is amorphous, and crystallized in long acicular prisms, 

 which are frequently diverging and interlacing. 



It exhales a slight bitter argillaceous odour when bjreathed 

 upon. 



