INDEX. 221 



Rainy River Hamilton Exposures 53 



Round Island 24 



Rock Oil 27; 32 



River Systems of Lower Peninsula 3 



Racine River 4 



Red Clay Beds of Drift 12, 13 



Rock Falls, Waverly Group 76 



Rifle River, " " 78 



" " Coal Explorations 141-143 



Slate Quarries, Huron Ba)^ 159 



Salt, Boring for Rock Salt, Alpena 40 



" Brine of Michigan, Geological Position 69, 91 



Saginaw River , 5 



' ' Valley Artesian Borings 94 



Sand Rock Bed, Point of Barques Lighthouse 74 



" Beach, Waverly Group 76 



Sable City Salt Wells 78 



Shales of Waverly Group 88 



Six-Mile Creek Outcrops of Coal Measures 139 



Sections through Coal Measures in Jackson County 123-126 



Sink Holes in Helderberg Limestone Districts 35 



" " " Thunder Bay Region 45-47 



Shales, Bituminous, of Hamilton Group 61 



Shell Marl Deposits '. 15 



Shoemaker's Limestone Quarries 115 



Shiawassee River 5 



Sleeping Bear Point 13 



Soils of Lower Peninsula 16 



Surface Material of Lower Peninsula 9 



" Elevation of Lower Peninsula • -2, 3 



Strontianite 28 



Stylolites , 32 



Swan Creek Quarries 32 



Stony Point, Thunder Ba}^ 42 



" " Hillsdale County 80 



Spring Arbor Limestone Quarries. 115 



" " Coal Mine.. 129 



Standish, Boring for Coal 144 



Sunken Lake 46 



Sugar Island ■. 49 



Thunder Bay Island : 48 



" " River ... 5 



Trowbridge's Mills 44 



Titibawassee River 5 



Tawas Salt Wells 78, 79 



Vegetable Remains in Water-lime Group 32 



Water-lime Group , 29 



Waverly Group • • • • 69 



