CONTENTS OF PART II 
Tage. 
Cn after I. Introduction 101 
Geography 101 
Previous exploration 102 
CnAPTER II. Igneous rocks 105 
Granites 1 05 
Mapleton granite 105 
Drews Lake granite 106 
Rhyolites 107 
Haystack rhyolite 1 07 
Rhyolite of hills adjoining Haystack 109 
Trachytes 109 
Hedgehog trachyte 110 
Chapman trachyte 110 
Woodland trachyte 110 
Quartz-trachytes 110 
Quoggy Joe quartz-trachyte Ill 
Quartz-trachyte of Township 9, Range 3 Ill 
Andesites Ill 
Edmunds Hill andesites 112 
Hobart Hill andesites 113 
South Mapleton andesites 113 
Castle Hill andesites 114 
Diabase 114 
Aroostook Falls diabase - 115 
Mars Hill diabase 115 
Teschenites 116 
Chapter III. Clastic rocks 118 
Introduction and classification 118 
Volcanic tuffs 119 
Field description 119 
Castle Hill tuffs 120 
Normal type 120 
Silicified type -* 121 
Tuff in northeast part of Ashland Township 121 
Tuff on the Ashland-Sheridan road 121 
Petrography 122 
Castle Hill tuffs 122 
Normal type 122 
Analysis 124 
Discussion of analysis 124 
Silicified tuff of Castle Hill 124 
Tuff in northeast part of Ashland Township 125 
Microscopic description 125 
Tuff on the Ashland-Sheridan road 125 
Microscopic description 126 
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