INDEX 



437 



Imbricated structure of sedimentary 



rocks, in, 315 

 Impounded streams, 348 

 Impregnations, 252, 260 

 Inclination of strata, 157 

 Inclusions in minerals, 4, 37, 43 

 Incrustation of fossils, 91 

 Index-beds, 287 

 Injection-plexus, 207 

 Inliers, 178 



Insolation, 57, 58, 1 52, 369 

 Interbedded igneous rocks, 208 

 Intermediate igneous rocks, 40 

 Intersection of faults, 169 ; of lodes, 242 

 Intervals indicated by planes of bedding, 



109 

 Intratelluric stage of consolidation, 35 

 Intrusive rocks, 184 

 Inversion, 138 

 Iolite, 25 



Iron-hat, 249, 256. See Gossans 

 Iron ores, 229, 230, 231, 232, 235, 236, 



249, 258, 264 

 Ironstones, 67 



Irregular ore-formations, 258 

 Islands, fringing or marginal, 424 

 Isoclinal folds, 138 

 Italy, crater lakes of, 422 



JACYNTH, 8 



Japan, 265 



Jargoon, 8 



Jasper, 5 



Jasp-opal, 6 



Joints, 144 ; influence of changes of 

 temperature upon, 145 ; in bedded 

 rocks, 145 ; in igneous rocks, 147, 

 198, 204; in schistose rocks, 150; 

 origin of, 150 



Jordan Valley, 414 



Jura Mountains, 397 



Kames, 316 



Kankar, 122 



Kaolin, 62, 126 



Kaolinite, 26, 62 



Keeweenaw Point, copper of, 262 



Kentallenite, 46 



Kersantite, 48 



Kidney- ore, 6 

 Klapperstein, 122 

 Knotted slate, 76 

 Kugel-granit, 124 

 Kupferschiefer of Mansfeld, 

 Kyanite, 26 



263 



Labradorite, 12, 13 



Laccoliths, 19T, 195, 402 



Lac d'Aydat, 420 



La Celle, tufa of, 98 



Lacustrine deposits, 318 



Ladoga, Lake, 419 



Lake Caledonia, 373 



Lake Superior, copper, 262 



Lakes, 348, 419 



Lamellated lodes, 245 



Lamination, 107 ; diagonal, 115 



Landscape-marble, 123 



Lapilli, 53 



Lateral secretion of ores, 269 



Laterite, 58 



Laurvikite, 46 



Lava, consolidation of, 35 



Law of mineral combination in igneous 



rocks, 39 

 Layers, 108 

 Leached guano, 72 

 Lead ores, 249, 256, 269 

 Leaf- by-leaf injection, 188 

 Lee-seite, 314 

 Leucite, 13 ; -basalt, 52, 89 ; -phonolite, 



48 

 Leucitite, 52 

 Leucitophyre, 48 

 Leucoxene, 7, 25 

 Level-course in coal mines, 147 

 Level-of-no-strain in earth's crust, 142 

 Lherzolite, 52 

 Lias, 115, 232 

 Liebenstein, dyke at, 206 

 Lignite, 71 

 Limburgite, 52, 89 

 Limestones, 69, 82 ; replaced by 



haematite, 260 

 Limonite, 7, 67, 231 

 Liparite, 43 

 Lithomarge, 26 

 Liver-quartz, 372 ; -rock, 60 

 Llanos of S. America, 412 



