
INDEX 
Rocky Mountains, 143, 401 
Roman Camp Hill, 179 
Roofing-slate, 76 
Rotten-stone, 71 
Rubicelle, 8 
Ruby, 9; spinel-, 8; balas-, 8 
Russia, undisturbed palzeozoic strata in, 
107 ; ores of, 229, 234, 236; lakes of, 
419 
Rutile, 7 
SADDLE-REEFS, 255 
Sandstone, 60, 84, 93; concretionary, 
123; columnar, 149 
Sandstone-dykes, 211 
Sand, volcanic, 53 ; -dunes, 391, 396 
Sanidine, 11 
Sapphire, 9 
Sarawak, ores of, 266 
Sarcen-stones, 378 
Sardonyx, 5 
Satin-spar, 30 
Saussurite, 12 
Scandinavian Mountains, 407 
Schillerisation, 49 
Schistose structure, 74 
Schists, 74, 88, 94; fossils in, 94; 
joints in, 150; ores in, 234 
Schorl, 25 ; -granite, 42 
Scoriz, 53 
Scree-breccia, 57 
Seam, 109 
Secondary enrichment of lodes, 249 
Secondary minerals, 37 
Secondary mountain-ranges, 401, 404 
Secretionary ore-formations, 268 
Secretionary structure, 124 
Secretions in granite, 42; in rhyolite, 
126 
Sections, horizontal or profile, 325; 
vertical, 329 
Sedentary soils, 376 
Sedimentary ore-formations, 269 
Sedimentary rocks, 59 
Segregation-veins, 208 
Selenite, 30 
Semi-opal, 6 
Sepiolite, 23 
Septaria, 121 
Serpentine, 23, 79, 213, 221, 382 
44] 
Sewage-fields, dangers from, 365 
Sgurr Ruadh, 174 
Shale, 63; alum-, 63; arenaceous, 63; 
carbonaceous, 63; oil-, 63 
Shear-structure, 80 
Sheeted zones, 238 
Sheets, intrusive. 
Shell-marl, 70 
Shelly limestone, 70 
Shode-stones, 338 
Shoots, 245 
Siderite, 29, 236 
Sidlaw Hills, ror 
Signs used on geological maps, 281 
Silicates, 9 
Siliceous concretions, 120 
Siliceous rocks, 82 
Siliceous sinter, 6, 66 
Sillimanite, 26 
Sills, 192, 300 
Silser See, 421 
Silvaplana See, 421 
Silver, 229, 251, 256, 260, 263, 265 
Simple lodes, 240 
Slates, 76, 224 
Slaty cleavage, 224, 302 
Slickensided stones in lodes, 245, 251 
Slickensides, 150, 157, 171, 313 
Smaragdite, 17 
Soapstone, 23 
Soda-lime-felspar rocks, 48 
Sodalite, 14 
Soil, 57, 282, 368 
Soil-cap, 375 
Solenhofen limestone, 264 
Solfataric or after-action, 266, 268, 339. 
See also Pneumatolytic action 
Solutions, siliceous, 3 
Soulvein, 406 
Southern Uplands, Scotland, 407 
South Downs, 410 
Spathic iron-ore, 68 
Specific gravity of rocks, 89, 428 
Specular iron, 6 
Spheerosiderite, 29; nodules of, 122 
Sphene, 25 
Spherulite-rock, 45 
Spherulitic structure, 34, 45 
Spinel, 8 
Spinelloids, 8 
See Sills 
