e aidiene Fai a 
Geology and Mineralogy of a part of Massachusetts, §c.° 9 
amines with the mica-slate of the eastern part of this 
section 
Trap or Hornblende Rocks. Cleaveland. 
This name, as is observed by Prof. Cleaveland, * in fact 
conveys no definite idea of any one species or sort of rocks.?* 
* Cleaveland’s Min. and Geol. 9a Ba. p- 743. There never Was a more 
conclusive reason for discontinuing the use ofa name. While some of the 
Tro: 
by describing ese several roc socks * their order, under this generic na 
in Rees’ Cyc. into a tabular form. See also Art. Mineralogy in the New 
Ed. Encye. dona wiension r view 
TRAP OR HORNBLENDE ROCKS. 
Primitive Trap. 
1, Common hornblende, asa rock. 
Var. 1 , Geosuier ende. 
2, Hor 
2, Hornblends and Feldspar. 
Var. 1. Primitive Greenstone, 
Do. Greenstone Slate. 
3. Intimate mixture of hornblende and feldspar with some mica. 
2 Cg ‘Aupaaell Known by their transition associates, 
Secondary Trap Rocks. 
és dary greenstone, or greenstone trap. 
-~ renee oe A gr OF gr 
3. Wacke, &e. &c. 
n, though no reason can be given, as it 
Sientte must form 
ia now dated, why it ethoald not not te ranked with the hornblende rocks, 
Vor. VIII. No.1. 2 
