This page has been validated.
358
INDEX.
Thickness in Scotland, 160. Its change of character in South Devon and on the Severn, 160. Raised by Murchison to the rank of a system, 162. Real littoral types of, 245.
Sandrycock, deposit of, ii. 60.
Sansan, remains of quadrumana in lacustrine deposits of, i. 100.
Santorini, Islands of, changes in the, ii. 236.
Saurians, Professor Owen's division of, i.92. Fossil remains of, 92, et seq. See Organic Remains.
Saussure, M., on the mountains of Switzerland, i. 38. On the strata of Buet, ii. 145. On the temperature of Bex mines, 272.
Sea Fell, height of, i. 133.
Scenery, of England, its character dependent on strata of the district, i. 176. ii. 325. Of the earth, dependent on its geological formations, ii. 324.
Sciacca, Island of, its transitory nature, ii. 222. 237.
Scriptures, Jewish, their use, i. 10.
Scrope, Mr., on volcanic rocks, ii. 83.
Sea and land, distribution of the earth into, ii. 286.
Secondary system, table of its deposits, i. 54. Its rocks, 66. Disturbances at its close, 244. See Carboniferous and following Systems.
Sedgwick, Professor, Lower Cambrian system of, i. 124. His arrangement of the clay-slate system, 124, et seq. His investigation of the Silurian system, 146. 162. His opinion respecting shelly marls of Gosau, 237. His section of the tertiary series, 258. His description of the granite veins of Trewavas Head, ii. 105. His account of the strata of the Caldew, 140.
Selwyn, Mr., reference to, i. 129.
Serpentine, where found, i. 121. Its composition, ii. 94.
Severn, fossils of the, i. 140. Deposits of gravel in valley of, 301. Its rock terraces, ii. 7. Analysis of its waters, 34.
Sewalick Hills, Hindostan, remains of quadrumana in, i. 100.
Shap, dip of stratified rocks at, i. 37.
Sharpe, Mr., his illustration of the idea, that "pressure" is a cause of cleavage, ii. 117. 120, et seq.
Shells, freshwater, found in I. of Wight, i. 77. Found in raised sea beaches, 321, et seq. Beds of, 336. Classes of, at various depths of the sea, 340. See Organic Remains.
Sheppy, fossil remains of turtles found in the clay of, i. 92.
"Shoot" of ore, meaning of the term, ii. 168.
Siebengebirge, trachytic mountains of, ii. 223.
Sienite, composition of, ii. 93. Of Christiania, 143, 144.
Sienitic granite, occurrence of, in Strontian and Ben Cruachan, i. 108.
Silica, proportion of oxygen in, i. 24. ii. 73.
Silurian System, Sir R. Murchison's classification of, i. 124. 136. Tables of deposits of, 139. 157. Its composition, 136. Its structure, 136. Succession and thickness of its strata, 138. Organic remains found in, 140. Its geographical extent, 146. Its physical geography, 148. Igneous rocks of, 148. Mineral veins found in, 149. Close of the Silurian period, and ensuing disturbances of the earth's crust, 149.
Silver ore, proportions of, found in mines of Freyberg, ii. 174.
Silvertop, Colonel, his account of the deposits of the Alhama beds, ii. 44.
Skáptaa Jokul, great eruptions of, ii. 211. 219. Mr. Lyell's description of, 212.
Skiddaw, granitic veins of, i. 109. Igneous rock of, 121. Clay slate of, 126. 129. Height of, 133.
Skye, Island of, Macculloch's account of, ii. 96. 126.
Slate system, i. 124. See Palæozoic Strata and Clay-slate System.
Slates, metamorphic, how and where found, ii. 139, 140.
Smith, Dr. W., reference to, i. 44. His notice of disturbed strata at Pucklechurch, 49. Signification attached by him to the word stratum, 60. His principles confirmed by Murchison, 140. His opinion respecting the divisional strata of England, 218.
Snow, the parent of glaciers, ii. 19.
Snowdon, Snowdonia, abundance of zoophyta in summit of, i. 75. Clay-slate of, 126. 129. Porphyry and greenstone of, 134.
Society Islands, coral reefs of the, i. 332.
Soil, or external investment of the land, an object of interest to geologists, i. 33. Its depth ex-
