466 



Report of the State Geologist. 



the Drowned Lands, which until fifty years ago was an undrained and useless 

 swamp, but is now rich farming land. This area extends from Denton on 

 the north to the New Jersey state line, a distance of twelve miles. Its width 

 is from two to three miles and its area within the county, 17,000 acres. 

 The lake had its origin in a drift dam northeast of Denton. The Wallkill 

 river follows a winding course along the western side of this area, and sub- 

 merges it entirely during the spring floods. Other lake bottoms are the 

 Greycourt meadows, Black meadow swamp, Pine swamp, etc. 



Several excellent examples of lake-filling are to be seen in Orange 

 county. Of these the swamp at the north end of Orange lake west of 

 Newburgh show s the former extent of the lake. Others are Glenmere lake 

 east of Florida, Little Cedar pond two miles southeast of Sterling, and Little 

 Long pond two miles south by east of Southfield. The rocks are often 

 scratched and smoothed by the ice, and a fine example of glacial polishing 

 northwest of Monroe deserves special mention. This is in a field west of the 

 road from Monroe to Bagg's clove and just before a road turns off to the east 

 along the base of Bull liill towards Oxford. The Oriskany quartzite has here 

 been polished until it presents a surface like a mirror, and objects can be 

 distinctly seen reflected in it. On Shawangunk mountain the striae are 

 N. 30* E. and N. 60° E. 



Economic Geology of Orange County. 



Road Materials. Orange county has an abundance of good road-making 

 materials, but in few sections of the county are they taken advantage of, owing 

 either to indift'erence on the part of those persons on whom the maintenance 

 of the roads depends, or to a lack of the knowledge of the value of these 

 materials. 



The old method of working the roads by digging a mass of loose stones, 

 dirt and roots from the roadside and throwing it upon the road, is still 

 follow ed to a large extent, with the usual poor road resulting. This is the 

 mode in regions w here good material is near by, and even known to the road 

 repairers. Their use, however, requires a trifle more labor. 



The road-metals found within the county are: slate and shale, limestone, 

 sandstone, granite, and gravel. 



Grami I <m</ Sit ml The gravel has the most extended use of the available 

 road materials of the county. The localities furnishing it are too numerous to 

 require mention, and are found in every township. When the gravel is 



