vi Contents. 



PAGE. 



II. Sub-crystalline and fragmental rocks 45-143 



Quartzyte and Sandstone 45-93 



Potsdam Sandstone 45-51 



Sandstone of the Hudson River Group 51-57 



Medina Sandstone 57-71 



Sandstone of the Clinton Group 71 



Hamilton and Portage Groups 7 1-85 



Hudson River Blue-stone 71-78 



Chemung Group 85-92 



New Red Sandstone 92, 93 



Limestone _ 94-134 



Hudson-Cham plain valley 94-105 



Mohawk valley 105-115 



St. Lawrence watershed 116-1 20 



Lower and Upper Helderberg Groups 120-133 



Niagara Limestone 133, 134 



Slate 135-143 



Appendix : Statistics of Quarries 145-146 



Index 147-152 



