METAMORPHIC ROCKS. 443 
and are a part of the Chesnut ridge, are of mica slate, and garnets are not uncommon in this 
rock. 
At the “ Stone Church,” as it is called, half a mile southwest of Dover plains, the mica 
slate may be seen well exposed. The Stone Church is a place of some notoriety as a natu¬ 
ral curiosity. It is deep chasm of the mica slate rock, worn out much larger by the wearing 
action of a stream of water. It is very irregular in its dimensions, broader at bottom than at 
top, with large masses of rocks in the bottom, over which it is necessary for the visitor to 
clamber to explore its more remote parts. Segments of pot-holes may be seen in the rocks, 
Avorn by the action of pebbles and the rapid flow of water. Garnets were seen in the rocks 
at this place, and a single crystal of staurotide. 
Fine specimens of the mica slate containing garnets, may be obtained at the falls of the 
Wassaic creek, above the furnace in Amenia. 
Near the “ City,” in the northwest part of Amenia, the mica slate passes into talcose slate. 
On the road from Amenia northeast to the Chalk-pond ore bed, the limestone, mica slate, 
and talc slate were all seen in a position nearly horizontal. They may be better examined 
between the Chalk-pond ore bed, and the village called Perry’s corner. 
Limestone of a very white color, may be seen a little east of Mr. Ingraham’s, three fourths 
of a mile northeast of Amenia Seminary. 
The mica slate is sometimes loaded with iron pyrites. One locality, called the Alum rock, 
is in the south part of Amenia, not far southeast of the furnace. Another is on the mountain 
two miles southwest of Amenia, in contorted, talcy, micaceous slate. It is sometimes carbo¬ 
naceous. It dips ten to forty degrees to the west (Vide Plate 18, fig. 2). 
Garnets are stated to be abundant in the mica slate between Beekman and the southwest 
part of Dover, by Prof. Cassels. White limestone skirts the eastern base of the Chesnut ridge 
in Dover, and into Pawlings. 
The limestone at some of the marble quarries near Dover plains is in nearly vertical strata. 
Generally, all the strata of rocks in this region dip to the east-southeast at high angles. Pro¬ 
fessors Cassels and Merrick explored the Dover valley south into Pawlings, almost to Putnam 
county, and found it skirted nearly the whole distance on the west by white limestone in nearly 
vertical strata, dipping seventy to eighty-five degrees to the east. The strike was almost north 
and south. 
“ The Dutchess county marble varies somewhat in its characters. It is almost always 
dolomitic, or composed of the carbonates of lime and magnesia invariable proportions. Some¬ 
times it is large grained and quite compact; at others it is fine grained, and so loose in its 
texture as to be unfit for a building material. A specimen of this marble from Dover, which 
was of a snow-white color, had a granular texture, and was as friable as loaf sugar, gave upon 
analysis the following results in 100 parts, viz : 
Carbonate of lime, . 60-50 
Carbonate of magnesia, . 39.50.”* 
Prof. Beck’s Fourth Geological Report, p. 61, 
56* 
