I50 



NEW YORK STATE MUSEUM 



in such abundance as to cause much waste. From between them 

 the purer streaks of limestone were selected and used as stock 

 in the furnaces. The rejected dumps now furnish interesting 

 inaterial for the mineralogist, since well terminated crystals at 

 times project into pockets of calcite in such relations that they may 

 be easily freed. 



The pure, white limestone is occasionally replaced by the ser- 

 pentinous variety, ophicalcite, locally called Moriah marble, .and 

 this will be again referred to under ornamental stone. 



The quarries in the Grenville have been shut down for years, 

 since, although the old Cedar Point furnace is still in vigorous 

 campaign the necessary limestone is elsewhere obtained. The 

 largest of the old quarries is the Pease, just north of Mill brook 

 in the outskirts of Port Henry. An impres-sive face of limestone 

 is exposed with a large black sheet of hornblende schist capping 

 the top. A half mile farther north and on the northern side of the 

 brook which flows into Craig harbor, is another opening, quite 

 similar in geological relations. A third one lies on the western 

 side of the ridge which separates Mineville from the lake, and is 

 just south of the Pilfershire iron mines on the east side of Barton 

 l)rook. In this last named quarry is the broken dike or sheet of 

 hornblendic rock, shown in plate 9. There are many other places 

 where this same limestone could be opened up if needed but at 

 present there seems to be no call for the material. 



The present source of flux for the furnace is the faulted block 

 of Beekmantown limestone on the lake shore just south of Craig 

 harbor. It furnishes a somewhat silicious, magnesian variety and 

 is broken and carted to the furnace yard as needed. Were other 

 varieties required, the Chazy and Trenton ledges on Crown point 

 would deserve investigation, since the Chazy on Willsboro point is 

 a fairly pure calcite, although it varies somewhat in difl'erent beds. 



In a small way the Grenville limestones have been quarried and 

 burned for lime in former years. The industry was, however, 

 rather a feature of the earlier and more isolated conditions than 

 those of today. The ruins of an old kiln are still recognizable 

 along the road to North Hudson and about 3 miles west of Moriah. 

 Corners. Another one is in the western foot of Woods hill, about 

 a mile north of Elizabethtown. From stray bits of clinker it is 

 probable that one also was in existence near the ledge on the north- 

 eastern feeders of Jackson brook. 



To a small extent the Beekmantown limestone from the furnace 

 quarry, near Port Henry, has been used for macadam, but there 



