250 Gramiic veins and beds in Chester, Mass. 
quartz found in the mine, and is often heaniiielin tinged 
with malachite in dendritic forms. “ 
Fetid Quariz. Forms a gangue for the blende. — , 
7. Puddingstone. In considerable masses, deposited ¢ on 
the argillite. 
8. Clay. Ofa grayish color, produced by the decom. 
position of the slate. 
9. Sulphuret of Iron. In small Bee in the argillite, and 
also amorphous. 
Salisbury, July 18, 1824. 
tO 
Art. 1X.—.Nolice of theGramtic veins and beds in Chester, 
Mass. by EK. HEumons. 
Cuester, Juny 8, 1824. 
‘Tue face of the country in and about Chester is hilly 
and mountainous, rising into abrupt precipices of various 
heights, from 10 to 50 or 80 feet in perpendicular elevation. 
The direction of the rock strata and billsis N. and 5. with 
an inclination of only a few degrees to the E. or W. and 
in some places, as in deep vallies, the strata are vertical. 
The principal rock is mica-slate of fine and nearly compact 
structure. It breaks into rhombic fragments of various 
sizes, having sharp and well defined edges. Imbedded m 
the rock are garnets ofthe size of small shot, staurotide 
and cyanite. In many strata these minerals constitute by 
far the largest portion of the rock. The dark colour 1s 
owing insome instances to a mixture of primitive trap, in 
others, to the presence of carburet ofiron. On examining 
the rocks of Chester, the attention of the geologist is at- 
tracted to the number and variety of the granitic beds and 
veins. The granite is gray and of a coarse texture, con- 
taining in many instances targe blocks of feldspar and 
quartz. The plates or tables of mica are often beautiful 
and are portions of regular crystals. The quartz is always 
strongly fetid, while the feldspar in immediate contact ts 
inodorous. The quartz is often beautifully impressed by 
insuiated tables of mica. ‘There are several positions in 
which the granitic beds and veins are found. The first 
(see fic. 1. pl. Uf.) which f shall notice, is a horizontal vein 
