INDEX. 



327 



Mica described, 38. 



Mica schist, 39. 



Michigan salt, 132, 133; gas, 143. 



Milwaukee bricks, 44. 



Mind in physiological activities, 309; 



in the method of nature, 311. 

 Minerals denned, 37. 

 Mines and mining, 119. 

 Mississippi River, sediments of, 48. 

 Mont Cenis Tunnel, 98. 

 Monti Rossi on ^tna, 88. 

 Monument Park, 55. 

 Moon, origin of, 219 ; tidal action of, 



219, 232. 

 Moraine defined, 28; of continental 



glacier, 273, 276. 

 Mosasaur, 171, 251. 

 Moss petrified, 35. 

 Mountains, structure of, 108 seq.; of 



upheaval, 112, 227 ; erosion of, 112 ; 



of relief, 113 ; formation of, 113, 246 ; 



theories of, 114; trends of, 117; 



thickness of strata in, 118; syn- 



clinorium theory of, 118. 

 Mouths of great rivers, 49. 

 Mud from Vesuvius, 86. 

 Murraysville gas wells, 145, 147. 

 Mylodon, 159. 



National Park described, 79 seq. 



Nature, interpretation of, 306 seq. 



Nautilus and its ancestry, 184 seq. 



Nebulae, 213, 214 seq. 



Nebular theory, 214 seq., 295. 



Neff, Peter, and gas production, 142. 



Nevada continent, 267. 



Neve, 22, 272. 



Newberry, J. S., on Table Mt. plants, 



282. 



New England reptiles, 248. 

 Niagara gorge, 43, 277 ; age of, 291. 

 Niagara Limestone, 186. 

 Nile delta, 292. 

 Northern Land of America, 233, 235, 



264; uprising of, 266. 

 November meteors, 211. 



Obelisk, New York, 39, 113. 



Ocean depths, explored, 56 ; origin of 

 219 ; chemical war in 224 seq.; sedi- 

 mentation in, 228. 



Odontornithes,261. 



Oil. See "Petroleum." 



Oil regions, 139. 



Old Faithful geyser, 81, 82. 



Oldham on Earthquakes, 104. 



Old Red Sandstone, 184. 



Onchus, oldest vertebrate, 238, 239, 301. 



Ontogeny, 297. 



Onychodus, 237, 239, 258, 301. 



Oreodon, 257. 



Ores of lead, 24 ; of iron, 35, 125 seq. 



Orthoceras, 188, 194, 234. 



Otozoum, 249, 250. 



Outcrop defined, 67, 75. 



Oysters in Cretaceous rocks, 171. 



Ozark Range as an obstacle, 43. 



Palaeaspis, 238. 



Palaeozoic, Great System, 72; popu- 

 lations, 234. 



Palmier! and earthquakes, 85. 



Panama cliffs, 62. 



Parameryx, 257. 



Park, National, described, 79 seq. 



Peat, 153. 



Pebbles, 14. 



Pelagic forms, 59. 



Periods, 74. 



Perrey on earthquakes, 105. 



Petoskey, fossils at, 181. 



Petroleum, geology of, 135; laws of 

 accumulation of, 136. 



Pilot Knob, 128. 



Pittsburgh gas, 144 ; production of, 146. 



Placers, 96. 



Placoderms, 236. 



Plans in nature, 190, 301. See 

 "Method." 



Plantigrade mammals, 255. 



Plants, in coal beds, 50 ; of coal pe- 

 riod, 244; origin of, 216. 



Plateau Province, 268, 269. 



Plesiosaur, 251. 



Ponds filling up, 47. 



Porphyry, 40. 



Potholes, 276. 



Potsdam Sandstone, 111, 192, 196. 



Prairies, origin of, 280. 



Preadamites, question of, 287. 



Precipitations, primeval, 225. 



Prophetic types, 258. 



Protozoans, reign of, 72. 



Pteraspis, 238. 



Pterichthys, 239. 



Pterosaur, 251, 260. 



Quartz, and its varieties, 87 ; primi- 

 tive, 226. 

 Quartzite, 37, 226. 



