434 



INDEX 



Crush- breccia, 81, 170. See Breccia 

 Crustal movements, slowly effected, 



x 75> 4°3 5 a cause of jointing, 153 ; 



influence of, on coast-lines, 423 

 Cryptocrystalline structure, 36, 43, 44 

 Crystalline igneous rocks, 40 

 Crystalline schists, 88 

 Crystallites, 34 



Cumberland, ores of, 259, 269 

 Current-bedding, 1 15 

 Current marks, 116 

 Curvature of strata, 127, 133 

 Curve of erosion, 417 

 Cycle of erosion, 401, 404, 412, 414, 



422 



Dacite, 49 



Danube, River, 391, 411 



Dead Sea, 419 



Deep leads, 234 



Deflation, 58, 369 



Deformation-mountains, 396 ; -valleys, 



413 

 Deformation of crust, slowly effected, 



175, 403 



Deltas, 116, 411, 417 



Dendrites, 123 



Denudation, 239, 250, 309, 391, 398, 

 410. See also Erosion 



Depth of lodes, 239 



Derbyshire, lead ore of, 269 



Derivative rocks, 55 ; soils from, 383 



Desquamation of rock-surfaces, 152, 

 369 



Determination of rocks in the field, 81 



Devitrification, 35, 36, 45 



Diabase, 50 



Diagonal bedding, 1 15 



Diallage, 18 



Dichroite, 25 



Diorite, 48, 86, 89 ; orbicular, 48, 124 ; 

 soils derived from, 380 



Dip, 127,427 



Dip-faults, 158 



Dip-joints, 146 



Dip-slope, 296 



Dirt-bed of Portland, 100 



Disease in relation to geological con- 

 ditions, 366 



Disintegration of rocks, 368 



Dislocation-mountains, 401 ; -valleys, 

 413 



Dislocations. See Faults 



Disseminations, 261 



Dissolution-basins, 420 



Divergent lodes, 242 



Dolerite, 50, 89 



Dolomite (mineral) 29 ; (rock), 65, 82, 

 124 



Downs, North and South, 410 



Downthrows, 155 



Drainage, natural underground, 350 ; 

 sewerage, 364 ; streams and rivers, 

 415 



Drift soils, 376, 385 



Drumlins, Drums, 312, 317 



Druse and drusy cavities, 125, 246 



Dry valleys, 414 



Dunderlandstal, ores of, 235 



Dunes, 391, 396 



Dunite, 52 



Dura Den, 263 



Dust, 58, 376, 391 



Dykes, 197, 198, 202, 211, 301 ; com- 

 posite, 206 ; effect of, on underground 

 circulation of water, 356 



Dynamo-metamorphism, 223 



Earthquakes a cause of jointing, 154 



Eclogite, 79 



Economic geology, 330 



Effusive eruptive rocks, 208 



Eifel, crater-lakes of the, 420 



Elaeolite, 14 ; -syenite, 46 



Elements, 31 



Elk Mountains, laccoliths of, 191 



Embankments, foundations of, 349 



Emery, 9 



Enclosures in minerals, 4, 37 



End of coal, 146 



Endogenous veins, 207 



Endomorphs, 6, 37 



Engadine, lakes of, 421 



Engineering and geological structure, 

 340 



Enstatite, 18 



Eocene, climate of, 99 ; contrast be- 

 tween deposits of, in London Basin 

 and in Switzerland, 107 



Epidote group, 24 



