54 Geology and Mineralogy of a part of Massachusetts, &c. 
bably | ferith oxillc offijien. Alco. in Middlefield and 
Bhester ; Emmons. It is a fine powder, and not very 
abundant in the rock; enough however to cover it with 
flame when thrown on the fire. The mica in this rock is a 
very bright green, and has sometimes been considered as 
oxide of chrome. 
Pulverulent sulphur is found also in Tyringham, i in mi- 
Vt. 
ca slate, and in ilmington, 
» Also i in Bogert oi in the singular mineral discovered 
by Dr. P 
3. PETROLEUM, 
Rises in small a on the surface of rather ap 
waters, in many pla 
4. GRAPHITE. 
Foliated and granular with augite at Hinsdale. Some- 
times it is nearly slaty, and in considerable quantity. Also 
in New Marlborough. 
The foliated variety is often found along the eastern part 
of this section, diffused through augite, granite, and va- 
rious minerals. It is often called sulphuret of molybdena, as 
Rost of is not supposed to be so distinctly foliated. 
at of i - however, is certainly graphite. Also in Cum- 
5.- PEAT. 
A bed of vegetable matter, approaching this substance, 
under the bed of mar! in Pittsfield. In Canaan, N. Y. 
arnes. 
CLASS IV. 
1. SULPHURET OF IRON, 
Too common to mention localities,—associated with 
most rocks and minerals. In Chatham, N. Y. in flattened 
