Ries — Geology oe Orange County. 



473 



support the hanging wall. The wall-rock is a feldspathic biotite gneiss which 

 dips steeply to the east. The ore-body is cut by a camptonite dike six feet 

 wide, and a horse divides the ore at the roof, but farther down extends across 

 the ore-body. According to Smock, this horse shows a synclinal structure. 

 Figure 21 gives a section and plan of the ore-body. 



The ore is non-bessenier and the following analysis of it is given in 



Smock's iv] Mill . 



Silica, 5.00 



Alumina, » trace 



Lime, 5.51 



Magnesia 1.19 



Manganese, .63 



Peroxide of iron, „ „ . 83.56 



Phosphorus, 2.30 



Carbonic acid, 1.05 



Water, 20 



99.44 



The slope is about 1,600 feet long, and the ore is raised in a car. It is 

 trammed to a point within two miles of Fort Montgomery, whence it is carted 

 to the river. This item of transportation would greatly increase the cost of 

 operation of the mine were it not for the fact that the entire plant is operated 

 by water-power. This is generated by two overshot wheels forty feet in 

 diameter and six feet wide. The mine- water is raised through a vertical shaft 

 located 900 feet east of the mouth of the slope. The ore is used in the 

 furnaces at Poughkeepsie. 



Soils. About two-thirds of the county is underlaid by the Hudson 

 rivei- slates, which are usually thinly covered with drift. The soil of 

 this region produces excellent hay and the area is extensively given over to 

 dairy farming, the products of which have made the county well know n. 

 Very little else is raised in the slate region, except in the northeastern 

 portion, where the stony soil and hilly ground produced by the coarse drift 

 and sandstone, are admirably suited for the cultivation of grapes. 



The limestone areas afford a good soil, in their more elevated portions, 

 but they are often areas of depression and occupied by swamp land. 



These swamps, however, occur not only in the limestone region, but also 

 in many parts of the slate area and form perhaps the most important agricul- 

 tural feature of the county. The rich black soil of the swampy tracts is 



