62 



NEW YORK STATE MUSEUM 



8 No. 143 Gypsum Deposits of New York. By D. H. New- 

 land and Henry Leighton. 94p. 20pl. 4 maps. 



Contents: 



Introduction 



History of the gypsum industry in 

 New York 



Composition and characters of gyp- 

 sum 



Uses of gypsum 



General geology 



Details of the distribution of 

 gypsum in New York 



Character of the gypsum in New 



York; chemical analyses 



Permanence of tlie gypsum supply 



Methods of prospecting and ex- 

 ploiting the gypsum deposits 



Origin of gypsum 



Properties of gypsum and theory 

 of its transformation to plasters 



Technology of gypsum plasters 



Bibliograph}' 



Index 



9 No. 145 Geology of the Thousand Islands Region. By H. P. 

 Gushing, H. L. Fairchild, Rudolf Ruedemann and C. H. Smyth, 

 Jr. 1949. 62p. 6 (5 colored) maps. 



Contents: 

 Introduction 

 Location and character 

 Summary of geologic history 



Igneous intrusions 



Close of the long period of ero- 

 sion 



Paleozoic sediments 



Subsequent history of the region 



The Pleistocene 

 The rocks 



Precambric rocks 



Great Precambric erosion 

 Paleozoic rocks 



Precambric surface underneath 

 the Potsdam 



Potsdam sandstone 



Theresa and Tribes Hill forma- 

 tions 



Pamelia formation 



Mohawkian series 

 Summary of Paleozoic oscillations 

 of level 



Dip of the Paleozoic rocks 

 Rock structures 



Foliation 



Joints 



Folds 



Faults [^ 



Topography 



Paleozoic altitude and climate 



Amount of erosion 



Original drainage 



Tertiary uplift 



Tertiary drainage 



Plateaus, terraces, scarps 



Lakes 



Underground drainage 

 Pleistocene geology 



History 



Physiography 



Glacial deposits 



Glacio-aqueous deposits 



Glacial erosion 



Prewisconsin glaciation 

 Economic geology 



Road metal 



Granite quarries 



Sandstone quarries 



Limestone quarries 

 Petrography of some Precambric 

 rocks 



P>leached granite 



Picton granite 



Alexandria syein'te 

 Granitized amphibolite and aniphi- 

 bolized granite (soaked rocks) 

 Index 



