INDEX 



Acid original rocka, 91-126, 144-151. 



, Age of, 12, 13. 



, Absence of copper in, 426. 



, Chronological relation of, to basic eruptives, 32, 432- 



436. 



, Classification of, 91. 



, Distribution of, 155. 



, Frequency of, 91. 



, Huronian and Kewe. n.r.e.m oompared, 403. 



, Kinds of, 112-125. 



, augite-syenite, &c, 112-124. 



, felsite and quartz-porphyry. 95-112. 



, granite, 125. 



, quart zless porphyry, 91-95. 



, Summary of, 126. 



, Views on origin of, 12, 150. 



Agate Bay, Amygdaloids of, 137, 287-289. 

 _""_, Olivine-diabase of 72, 76, 287. 



, Section at, 288, 289. 



Agate Bay Group, 284-294. 



at Agate Bay, 72, 288-290. 



, Amygdaloids of, 136, 286-289. 



, Anorthite-roek of, 292. 



, Bedding of, 288. 



, Copper possibly present in. 429. 



, Dikes of, 293, 294. 



at Encampment Bluff, 47, 285. 



at Encampment Rivor, 284. 285, 291. 



_- , Faults in, 290, 291. 



on French River, 284. 



on Gooseberry River, 286 



near Lester River, 292. 



, Olivine-diabase of, 76, 2SC. 



, Relation of acid and basic nicks of, 435. 



. Sandstone of, 292, 293. 



on Split-Rock River, 291. 



-on Talmage River, 286. 



, Thickness of beds of, 290. 



Thinning of, at eastern end of Minn, coast, 294, 29*. 



, Warping of beds of, 290. 



Agate Harbor, Trends and dips near, 17,-, 113. 



Agogebic Lake, Eastern Sandstone at. 360. 



, Lower Division at. 158. 



Albany and Boston mine. Angite-syenite pebbles of, 115, 118, 

 119, 190, 191. 



. Conglomerate of, 190, 191. 



, Dip of strata at, 187. 



, Qnartzless-porphyry of, 94,191. 



Albite in olivine-diabase, 70. 



Algoma mine, Ferruginous sandstone of. 374. 



Allouez mine, Dip at, 187. 



Alteration of aogite to eh].. rite 43, 64. 79. 



dialla 



ferrite, 79,93. 102, IN. 125. 



green substance, 71, 89. 



hornblende, 50, IN, V^ 



magnet > 5 



Ural 



Loid, 199. 



— of feldspars to ohloi ite 



through prehnite to chlorite, 64. 



to prehnii' 



glass base in quarts-porphyry, 101. 



ferruginous prebn 



in olivine diabase, 70. 



olivine to biotite, viridite, and tale 39. 



greenish substance, 38. 



magnet ite ( I ) , 39. 



ortboclase to chlorite, 51. 



plagioclase to chlorite ">i 



green substance, 71. 



prehnite, 46. 



prehnite to el.]- 



chloi Ite, ' to, 89. 



, 



ortboclase, 89. 



— , Pselld-aniygdaloiilal.il:; I t 



— of nralite to chlorite, 52. 



Aminicon River, Orthoolaso gabbro of. 52, 54. 



, Rocks of, 255, 256. 



Amygdaloids. S7-91. 134-139 

 — , Absence in Suronian, I 

 ...n of, 89. 90. 199, 

 !.:5, 136. 



— of ashbeddiabs 



_, Constituents of, 88, 89. 



, Plagioclase of, 88. 



ion in. 9o. 421. 422, 

 — , Distribution of, 155. 

 _, Fluid..". 

 — , Matlil of, 87,88. 

 _. Pumpelly on, 89-91. 



— , Relations of, to diabase porphyrites, 87, 89. 

 —, Stratiform, 137. 

 Amygdolee of amygdaloids. 89. 90. 

 — , Elongatiou of, 130. 

 Analeite of amygdaloids, 90. 

 Auiniikie Group, 367-3S6. 



. Bill on •crowning overflow of, 381, 382. 



, Contact of, with Keweema "405. 



147) 



