218 NEW YOKK STATE MUSEUM 



and Putnam counties in tihtiis iron ore district and from the New 

 Jersey line at the southwest to the Connecticut boundary on the 

 east. Some of the largest and most productive mines in Orange 

 county have been worked more than a century." This county 

 was famous for its iron manufacture during the revolutionary 

 war b The greatesit development of the iron mines in Putnam 

 county has been since the opening of the Tilly Foster and 

 Mahopac mines or during the last 25 years. The distance 

 from public lines of transportation, the increased cost of work- 

 ' ing the smaller ' veins ' at greater depths, the low prices for iron 

 ore and the competition with the richer ores of other parts of our 

 country have necessitated the suspension of work in some of the 

 mines and led to the permanent abandonment of those most 

 unfavorably situated. The ore® of the Highlands district are the 

 hard, crystalline magnetites. They are generally rich, free from 

 titanium, but contain a slight excess of phosphorus above the 

 limit for the manufacture of Bessemer iron, excepting the Maho- 

 pac and Tilly Foster mines, which have yielded a large amount 

 of Bessemer ore, and a few small mines, but which are no longer 

 worked. 



The Adirondack Region, Including the Lake Champlain Mines 

 The Adirondack region, the great mountain plateau of northern 

 New York, is bounded by the valleys of Lake Champlain on the 

 east, of the St Lawrence river on the north and northwest, of 

 Black river on the west, and the Mohawk on the south. 



Magnetite is one of the common minerals in the Adirondacks, 

 and is widely distributed, both as a constituent or accessory 

 mineral in rocks, and in beds of workable extent. Mines have 

 been opened in all parts of the region, but the greatest develop- 

 ment has been in the valley of Lake Champlain, and hence the 

 ores are known in the market as Lake Champlain ores. 



The beginnings of iron-ore mining in the Lake Champlain val- 

 leywere early in the present century. Some of the forges were 



a Ore was discovered on the Sterling tract as early as 1750; the ForesToTDe^Tmh^ 

 was opened about the same time. 



wTmtT" lL-m ManUfaCtUrC ° f Ir0n in aU A 9™' fe y James M. Swank, Phlladel- 



