200 NEW YORK STATE MUSEUM 



Trenton limestone 



Under this bead the Chazy, Birdseye, Black river and Trenton 

 limestones are included. 



The Chazy limestone crops out in Eissex and Clinton counties 

 and in the Champlain valley — its typical localities. The beds 

 are thick and generally uneven. Begular systems of joints help 

 the quarrymen in getting out large blocks. Quarries at Wills- 

 boro Point and near Plattsburg are in the horizon of the Chazy. 

 The stone is suitable for bridge work and for heavy masonry. 



The members of the Trenton above the Chazy limestone are 

 recognized in may outcrops in the south eastern part of the 

 state; in the Hudson-Cham plain valley; in the Mohawk valley; 

 in the valley of the Black river and northwest, bordering Lake 

 Ontario; and in a border zone on the north of the Adirondacks, 

 in the St Lawrence valley. In a formation so widely-extended 

 there is, as might be expected, some variation in bedding, texture 

 and color. Much /of the Trenton limestone formation proper is 

 thin-bedded and shialy and unfit for building stone. In the Birds- 

 eye also the stone of many localities is disfigured on weathering, 

 by its peculiar fossils. Generally the stone is sub-crystalline, 

 hard and compact and of a high specific gravity and dark-blue 

 to gray in color. But the variation is wide, as for example, be- 

 tween the black marble of Glens Falls and the gray, crystalline 

 rock of the Prospect quarries near Trenton Falls. The variation 

 is often great within the range of a comparatively few feet ver- 

 tically; and the same quarry may yield two or more varieties of 

 building stone. In several quarries the Birdseye and Trenton 

 are both represented. Many quarries have been opened in the 

 formation and there are many more localities where stone has 

 been taken from outcropping ledges, which are not developed 

 into quarries proper. The more important localities which are 

 worked steadily are: Glens Falls, Amsterdam, Tribes Hill, Cana- 

 joharie, Palatine Bridge and Prospect in the valley of the Mo- 

 hawk; and Lowville, Watertown, Three Mile Bay, Chaumont 

 and Ogdensburg in the Black river and St Lawrence valleys. 

 The railroad and canal lines, which traverse the territory occu- 



